UNITED STATES DEPARTMENT OF THE INTERIOR 

Harold L. Ickes, Secretary

GEOLOGICAL SURVEY 

W. C. Mendenhall, Director

Water-Supply Paper 844

FLOODS OF MARCH 1938 

IN SOUTHERN CALIFORNIA

BY ,-

HAROLD C. TROXELL AND

Prepared in cooperation with the «*, 

FEDERAL EMERGENCY ADMINISTRATION OF 

AND WORKS PROGRESS

o r »- " :

. ^.j 

^ ^

* ^» " - n >-*

UNITED STATES

GOVERNMENT PRINTING OFFICE 

WASHINGTON : 1942

For aate by the Superintendent of Documents, Washington, D. C. ------- Price $1.25

CONTENTS

Page 

Abstract .............................. 1

Introduction ............................ 2

Administration and personnel .................... 2

Acknowledgments .......................... 3

General features of the storm and flood .............. 4

Collection of rainfall and runoff records ............. 14

Heteorologic and hydrologic conditions ............... 15

Precipitation records ..................... 15

Preparation of isohyetal maps ................. 46

Local rainfall characteristics ................. 49

San Dimas Experimental Forest ................. 54

Chronologic distribution .................... 58

Rainfall intensities ...................... 61

Comparison of rates of intensity with rates in previous storms . 91 

Storm movement ......................... 93

Antecedent precipitation .................... 95

Snow .............................. 96

Basic discharge records ...................... 98

Santa Ana River Basin ..................... 105

Santiago Creek at Santiago Reservoir, near Villa Park . . . 105 

San Gabriel River Basin .................... 106

San Gabriel River at flood-control reservoir No. 1, near

Azusa .......................... 106

San Gabriel River at Morris Reservoir, near Azusa ..... 108

West Pork of San Gabriel River at flood-control reservoir

No. 2, near Camp Rincon ....'............. 109

Sawpit Creek at flood-control reservoir near Monrovia . . . Ill 

San Dimas Creek at flood-control reservoir near San Dimas . 112 

Fern Canyon Watershed No. 2, near San Dimas ........ 114

Fern Canyon Watershed No. 3, near San Dimas ........ 114

Wolfskill Creek near San Dimas ................ 115

West Fork of San Dimas Creek near San Dimas ........ 116

Dalton Creek at flood-control reservoir near Glendora . . 117

118

120

121 

121 

123 

Santa Anita Creek at flood-control reservoir near Sierra

Madre .......................... 124

Little Santa Anita Creek at flood-control reservoir near

Sierra Madre ....................... 126

Eaton Creek at flood-control reservoir near Pasadena .... 127

Calleguas Creek Basin ..................... 129

Honda Barranca at Berylwood Road, near Somis ........ 129

Honda Barranca at Perkins Road, near Somis ......... 129

Maximum inflow to reservoirs .................... 131

Studies of basic discharge records in relation to basin characteristics and rainfall ........................ 136

Basin characteristics ..................... 137

Runoff .characteristics .........'............ 140

First phase, February 27 and 28 .............. 141

Second phase, Marth 1 ................... 148

Third phase, March 2 ..................... 148

Fourth phase, 6 p.m. Marjsh 2 to midnight March 10 ..... 148

Relation between rates of precipitation and rates of runoff . . 149 

Lag between precipitation and runoff ............ 162

Infiltration .......................... 166

Determination of flood discharge .................. 168

Computation of peak discharge ................. 168

Slope-area determinations ................. 169

Flow over weirs ...................... 170

Flow through contracted openings .............. 172

Extension of rating curves ................. 172

Discharge in unstable channels ................ 173

Computation of continuous records of discharge ......... 174

Derivation of discharge for periods of missing records .;. . 176 

Consistency of determinations of flood discharge ........ 182

Live Oak Creek at flood-control reservoir near La Verne 

Thompson Creek at flood-control reservoir near Claremont

Los Angeles River Basil)

Pacoima Creek at flood-control reservoir near San Fernando 

Tujunga Creek at flood-control reservoir near Sunland

. Ill
IV CONTENTS

Page

Records of stage and discharge at stream-gaging stations ...... 183

Explanation of data ...................... 184

Tia Juana River Basin ..................... 186

Cottonwood Creek at Morena Dam ............... 186

Cottonwood Creek near Dulzura ............... 186

Cottonwood Creek above Tecate Creek, near Dulzura ...... 187

Tia Juana River near Dulzura ................ 188

Tia Juana River near Nestor ... M ............ 189

Campo Creek near Campo ................... 190

Otay River Basin ........................ 191

Otay River at Savage Dam .................. 191

Sweetwater River Basin ..................... 192

Sweetwater River at Sweetwater Dam ............. 192

San Diego River Basin ..................... 192

San Diego River at El Capltan Dam, near Lakeside ...... 192

San Diego River near Santee ................ 193

Boulder Creek at Cuyamaca Reservoir, near Julian ...... 194

San Vicente Creek at Foster ................ 195

San Dieguito River Basin .................... 196

Santa Ysabel Creek near Mesa Grande ............ 196

San Dieguito River at Lake Hodges ............. 197

San Luis Key River Basin .................... 197

San Luis Key River near Bonsall .............. 197

San Luis Key River at Oceanside .............. 198

Santa Margarita River Basin .................. 199

Temecula Creek at Nigger Canyon, near Temecula ....... 199

Temecula Creek at Railroad Canyon, near Temecula ...... 200

Santa Margarita River near Fall Brook ........... 200

Santa Margarita River at Ysidora .............. 201

Ifurrieta Creek at Temecula ................. 201

San Juan Creek Basin ...................... 202

San Juan Creek near San Juan Capistrano .......... 202

Trabuco Creek near San Juan Capistrano ........... 202

Aliso Creek Basin ....................... 203

Aliso Creek at El Toro ................... 203

Santa Ana River Basin ..................... 204

Santa Ana River near Ifentone ................ 204

Santa Ana River near Prado ........ .......... 205

Santa Ana River at Santa Ana ................ 206

Mill Creek near Craftonville ................ 207

Plunge Creek near East Highlands .............. 208

San Timoteo Creek near Redlands .............. 209

Warm Creek near Colton ................... 210

Strawberry Creek near Arrowhead Springs .......... 211

Waterman Canyon Creek near Arrowhead Springs ........ 212

City Creek near Highland .................. 213

Devil Canyon Creek near San Bernardino ........... 214

Lytle Creek near Fontana .................. 215

Lytle Creek (east channel) at San Bernardino ........ 215

Lytle Creek (weet channel) at Colton ............ 216

Cajon Creek near Keenbrook ................. 217

Lone Pine Creek near Keenbrook ............... 218

Day Creek near Etlwanda .................. 219

Cucamonga Creek near Upland ................ 219

San Jacinto River near San Jacinto ............. 220

San Jacinto River at Railroad Canyon Reservoir, near

Elsinore ........................ 221

San Jacinto River ne&r Elsinore .............. 221

Elsinore Lake at Elsinore ................. 222

Temescal Creek near Corona .........*........ 223

Chino Creek near Prado ................... 223

San Antonio Creek near Claremont .............. 224

Santiago Creek near Villa Park ............... 225

Santiago Creek at Santa Ana ................ 226

Irvine Ranch drainage canal near Tustin .......... 227

San Gabriel River Basin .................... 228

East Fork of San Gabriel River near Canp Bonita ...... 228

San Gabriel River at Foothill Boulevard, near Azusa . . . ., 229

San Gabriel River at Pico ................. 230

San Gabriel River at Spring Street, near Los Alamitos . . . 231

Vest Fork of San Gabriel River at Caiq? Rincon ....... 232

Rogera Creek near Azusa .................. 232

Pish Creek near Duarte ................... 233

Sawpit Creek near Monrovia ................. 234

San Dimas Creek near San Dimas ............... 234

Dalton Creek near Glendora ................. 235

Little Dalton Creek near Glendora ............. 236
CONTENTS V

Page 

Records of stage and discharge at stream-gaging stations' Continued

San Gabriel River Basin Continued

Walnut Creek near Baldwin Park ............... 237

San Jose Creek near Whittier ................ 238

Coyote Creek near Artesla ................. 239

Brea Creek at Fullerton ............ A ..... 240

Carbon Creek at Olinda ................... 241

Los Angeles River Basin .................... 242

Los Angeles River near Van Nuys .............. 242

Los Angeles River near Universal City ........... 243

Los Angeles River at Los Angeles .............. 244

Los Angeles River near Downey ............... 245

Los Angeles River at Long Beach .............. 246

Browns Creek at Chatsworth ................. 246

Pacoima Creek near San Fernando .............. 247

Pacoima Creek at Mission Acres ............... 247

Tujunga Creek near flolby Ranch ............... 248

Tujunga Creek near Sunland ................. 249

Tujunga Creek near San Fernando .............. 249

Little Tujunga Creek near San Fernando ........... 250

Haines Creek near Tujunga ................. 251

Verdugo Creek at Del Valle Avenue, Glendale ........ 252

Verdugo Creek at Glendale- ................. 253

Arroyo Seco near Pasadena ................. 254

Santa Anita Creek near Sierra Hadre ............ 255

Little Santa Anita Creek near Sierra Hadre ......... 255

Eaton Creek near Pasadena ................. 256

Eaton Creek near El Monte ................. 257

Rubio Canyon Wash at Rosemead ............... 258

Alhambra Wash at Alhambra ................. 259

Rio Hondo near El Monte .................. 260

Rio Hondo near Montebello ................. 261

Rio Hondo near Downey ................... 262

Ballona Creek Basin ...................... 263

Centinela Creek near Culver City .............. 263

Ballona Creek near Culver City ............... 264

Benedict Canyon storm drain at Culver City ......... 265

Topanga Creek Basin ...................... 266

Topanga Creek near Topanga Beach .............. 266

Malibu Creek Basin ........................ 267

Malibu Creek at Crater Camp, near Calabasas ........ 267

Santa Clara River Basin .................... 268

Santa Clara River near Saugus ............... 268

Piru Creek near Piru .................... 269

Sespe Creek near Fillmore ................. 270

Santa Paula Creek near Santa Paula ............. 271

Ventura River Basin ...................... 272

Matilija Creek at Matillja ................. 272

Ventura River near Ventura ................. 273

Coyote Creek near Ventura ................. 274

Santa Inez River Basin ..................... 275

Santa Ynez River at Juncal Reservoir, near Montecito .... 275

Santa Ynez River near Santa Barbara ............ 276

Santa Ynez River below Gibraltar Dam, near Santa Barbara . . 277

Santa Ynez River near Santa Ynez .............. 278

Santa Ynez River near Lompoc ................ 279

Santa Maria River Basin .................... 280

Cuyama River near Santa Maria ............... 280

Huasna River near Santa Maria .'.............. 280

Salton Sea Basin ........................ 281

Palm Canyon Creek near Palm Springs ............ 281

Mojave River Basin ....................... 282

Deep Creek near Hesperia .................. 282

Mojave River at lower narrows, near Vietorville .. »... 283

Mojave River at Barstow .................. 284

West Fork of Mojave River near Hesperia .......... 285

Summary of flood discharges .................... 286

Physiographic and geologic features affecting flood runoff, by

Harold V. Peterson ........................ 300

Introduction .......................... 300

San Diego area ......................... 302

Mountain highlands ..................... 303

Coastal belt ........................ 304

River valleys ....................... 304

Effect of geology on flood runoff ............. 305

San Bernardino mountain area ...*............... 307

Geology of the San Bernardino Range ............ 308
VI CONTENTS

Page

Physiographic and geologic features affecting flood runoff Continued 

San Bernardino mountain area--Continued

Effect of the geology on the runoff ............ 310

Mojave River ........................ 311

Santa Ana River ...................... 312

Mill Cre«c ......................... 315

The frontal streams .................... 317

Cajon Creek ........................ 318

Lone Pine Creek ...................... 319

Upper Santa Ana Valley ..................... 321

San Gabriel mountain area ................... 322

San Gabriel Mountains ................... 323

Geology of the mountain area ................ 324

Faulting .......................... 325

Effect of geology on flood runoff ............. 326

San Gabriel River ..................... 327

Tujunga and Pacoima Creeks ......*........... 330

The frontal streams .................... 331

Lytle Creek ........................ 335

The valleys ........................ 337

The coastal plain ....................... 338

Santa Clara, Ventura, Santa Ynez, and Santa Maria drainage

basins ............................. 340

Relation of rainfall and runoff to geology ......... 341

Santa Clara River ..................... 342

Plru Creek ......................... 344

Sespe Creek ........................ 344

Other parts of Santa Clara drainage basin ......... 346

Ventura River ....................... 346

Santa Ynez River ...................... 348

Santa Maria River ..................... 350

Rainfall, runoff, and retention .................. 351

Antecedent precipitation and retention ............. 351

San Diego, San Dleguito, San Luis Rey, and Santa Margarita River

Basins ............................ 358

Santa Ana, San Gabriel, and Los Angeles River Basins ...... 364

Santa Clara and Ventura River Basins .............. 368

Santa Ynez and Santa Maria River Basins ............ 368

Artificial storage ......................... 369

Debris ............................... 372

Interception of debris by reservoirs and debris basins ..... 372

Movement of debris in stream channels on the valley floor . . . 377

Flood damage ............................ 381

Loss of life .......................... 382

Flood-damage survey ...................... 382

History of floods In southern California .............. 385

Index ............................... 395

ILLUSTRATIONS

Page 

Plate 1. Mouth of Santa Ana River, March 3, 1938 ......... 14

2. Overflow at mouth of Santa Ana River, showing area between Santa Ana River and Huntington Beach submerged 

on, March 3, 1938 .................... 14

3. A, B,-Debris deposits In Colton ............. 14

4. Break in levee of Santa Ana River, March 3, 1938 ..... 14

5. Overflowed land along Santiago Creek ........... 14

6. A,,B, Debris deposits in overflowed citrus grove ..... 14

7. Scenes on Los Angeles River near Los Angeles: A, Wash-out

on railroad.right-of-way; B, Damage to channel ..... 14

8. San Fernando Valley, March 2, 1938 ............ 14

9. Artificial channels across debris cones, March 2, 1938:

A, Outlet channel from Dunsmuir debris basin; B, Outlet 

channel from Eagle-Goss debris basin .... .~. .... 14

10. Property damaged by flood: A, Destruction by meandering

stream; B, Debris deposited" by meandering stream .... 15

11. Isohyetal map of southern part of southern California

showing total precipitation, in Inches, February 27 to

March 4, 1938 ................. In pocket
ILLUSTRATIONS VII

Page

Plate 12. Isohyetal nap of central part of southern California, 

snowing total precipitation, in inches, February 27 

to March 4, 1938 ................. In pooket

13. Isohyetal map of northwestern part of southern California, showing total precipitation, in inches, 

February 27 to March 4, 1938 ........... In pocket

14. Precipitation in part of southern California for indicated intervals of the maximum 24-hour period, 10 p.m. 

March 1 to 10 p.m. March 2, 1938 ........... 94

15. Fern Canyon Watersheds Nos. 1, 2, and 3 ......... 102

16. A, East Btiwanda Creek near Etiwanda; B, Slope-area

~ reach on Lone Pine Creek near Keenbrook ........ 174

17. Reconstructed gaging stations replacing structures destroyed during the floods of March 1938: A, San 

Gabriel River near Azusa; B, Cucamonga Creek near 

Upland ......... 7 .............. 182

18. Reconstructed gaging stations replacing structures destroyed during the floods of March 1938: A, San 

Antonio Creek near Claremont; B, Deep Creek" near 

Hesperia ........................ 185

19. Dunsmuir debris basin after excavation of debris: A, Excavated basin and inflow structure; B, Outflow 

structure ....................... 374

20. Dunsmuir debris basin full of debris, March 11, 1938: 

A, View upstream showing debris deposits up to altitude of inflow structures; B, View downstream ..... 375

21. Santa Ana River below lower Santa Ana Canyon, March 3,

1938 ......................... 394

22. Santa Ana River at mouth of Chino Creek, March 3, 1938 . 394

23. Santa Ana River near Norco, March 3, 1938 ........ 394

24. Break in levee of Santa Ana River, March 3, 1938 .... 394

25. Overflow area along Santa Ana River, March 3, 1938 . . . 394

26. Flooded citrus and walnut groves along Santa Ana River,

March 3, 1938 ..................... 394

Figure 1. Map of California showing area covered by this report . . 5 

2. Map of area covered by this report showing principal

drainage systems ................... 8

3* Profiles of Santa Ana River and its main tributaries . . 9

4. Profiles of San Gabriel River and its main tributaries . 10

5. Relation between altitude and precipitation in the vicinity of Mount Islip and schematic cross sections showing 

relative position of rain gages ............ 48

6. Cross sections showing altitude and precipitation in

Ventura County and in Los Angeles and San Gabriel River 

Basins ........................ 55

7. Cross sections showing altitude and precipitation in 

basins of Santa Ana and San Luis Rey Rivers and 

Temecula .Creek .................... 56

8. Isohyetal map and cross sections showing altitude and

precipitation in San Dimas Experimental Forest .... 57

9. Mass curves of accumulated precipitation at representative stations, February 27 to March 3, 1938 ...... 59

10. Hourly precipitation at representative stations, February

27 to March 3, 1938 .................. 60

11. Hours of precipitation and percentage of total, in excess 

of indicated rates, for groups of stations A to E in 

San Gabriel and San Bernardino Mountains and foothill 

areas ......................... 84

12. Average hourly precipitation for groups of stations A toE 85

13. Mass curves of accumulated precipitation for groups of

stations A to E.................... 86

14. Time of occurrence of maximum periods of precipitation

for groups of stations A to E............. 87

15. Rates of precipitation for groups of stations A to E . . 88

16. Graphs of discharge into various reservoirs in southern

California, March 1938 ................ 104

17. Maximum rates of runoff'for periods of 1 minute to 16

hours in certain areas in San Gabriel and Los Angeles

River and Calleguas Creek Basins ........... 133

18. Ratio of maximum discharge for indicated period to maximum 24-hour discharge in areas above certain dams in 

Santa Ana, San Gabriel, and Los Angeles River Basins . 135

19. Tujunga Creek Basin, showing segments used In determining

maximum concentration of area ............. 137
VIII ILLUSTRATIONS

Pag® 

Figure 20. Distribution of drainage area above flood-control dams

in San Gabriel and Los Angeles River Basins ..... 138

21. Hourly precipitation and runoff, February 27 to March 

5, for West Fork of San Gabriel River at floodcontrol dam No. 2 .................. 142

22. Hourly^precipitation and runoff, February 27 to March

5, for Live Oak Creek at flood-control dam ...... 143

23. Accumulated precipitation, accumulated runoff, and retention, February 27 to March 5, for baaIn of Vast 

Pork of San Gabriel River at flood-control dam Ho. 2 . 144

24. Accumulated precipitation, accumulated runoff, and retention, February 27 to March 5, for Lire Oak Creek 

at flood-control dam ................. 145

25. Minr1i«nB rates of precipitation and runoff, for periods 

of 5 minutes to 24 hours, in basins of West Pork of 

San Gabriel River and Live Oak Creek ......... 153

26. »»Trii»>i» rates of precipitation and runoff, for periods

of 5 minutes to 24 hours, in San Dlnas Creek Basin and 

Fern Canyon Watersheds Kos. 2 and 3 ......... 154

27. Relation between rates of precipitation and rates of

runoff during maximum periods of 24 hours and less for

typical areas in San Gabriel and Los Angeles River

Basins ........................ 156

28. Relation between maximum rates of precipitation and

maximum rates of runoff during indicated periods of

time for lowest rates of runoff ........... 159

29. Relation between maximum rates of precipitation and

maximum rates of runoff during indicated periods of

time for intermediate rates of runoff ........ 160

30. Relation between maximum rates of precipitation and 

maximum rates of runoff during indicated period of 

time for highest rates of runoff ........... 161

31. Time of occurrence of maximum periods of precipitation 

and runoff for basins of West Fork of San Gabriel 

River and Little Santa Anita Creek and Fern Canyon 

Watershed Ho. 2 ................... 163

32. Sketch map, water-surface profiles, and cross sections 

of the slope-area reach of Lone Fine Creek near 

Xeenbrook ...................... 171

33. Cross sections at cableway on East Fork of San Gabriel

River near Camp Bonita, February and March 1938 . . . 175

34. Rates of precipitation and runoff, for periods of 5

minutes to 24 hours, for City Creek near Highland . . 178

35. Time of occurrence of indicated maximum precipitation 

periods as observed at Devil Canyon and Del Rosa and 

probable time >of occurrence of runoff of City Creek, 

with discharge hydrograph of City Creek near Highland, 

March 1-4 ...................... 179

36. Retention curves for certain stations in Santa Ana, San

Gabriel, and Loa Angeles River Basins ........ 181

37. Precipitation, runoff, and gross and net retention on 

Strawberry Creek during rainy seasons of 19S6-27 and 

1937-38 ....................... 355

38. Precipitation, runoff, and gross and net retention on

Santa Anita Creek during rainy seasons of 1926-27 and 

1957-38 ....................... 356

39. Relation between average slope of drainage basin and

deposition of debris in reservoirs and debris basins

of the Los Angeles County Flood Control District . . . 376

40. Altitude of point of zero flow at stream-gaging station

on Santa Ana River near Prado, 1919-38 ........ 378
TABLES IX

fable 1. Dally precipitation, in inches, at standard gagea for the

period February 27 to March 4, 1938 .......... 16

2. Daily precipitation, in inches, at recording gagea for

the period February 27 to March 4, 1938 ........ 42

3. Summary of information regarding diatribution of standard 

rain-gage records for atorai of February 27 to March 4, 

1938, in southern California .............. 50

4. Percentage of total storm precipitation on indicated days 

at 10 representative recording stations in Los Angeles 

and adjacent counties for the period February 27 to 

March 3, 1938 ..................... 61

5. Precipitation, in inches, for period ending at indicated

time, February and March 1938 ............. 63

6. Duration and amount of precipitation, In excess of Indicated rates,February 27 to March 4, 1938 ........ 75

7. Maximum rates of precipitation, in Inches per hour, for 

shorter periods within the storm period February 27 to 

March 4, 1938 ..................... 79

8. Location, altitude, and storm precipitation for certain 

groups of stations In Santa Ana, San Gabriel, and Los 

Angeles River Basins .................. 82

9. Maximum precipitation during indicated periods for period

of record at selected stations ............. 92

10. Maximum dally precipitation during March 1938 at selected

stations compared with maximum previously recorded ... 94

11. Precipitation and departure from normal, In Inches, at 

typical stations, for periods from July 1, 1937 to 

February 5, 1938 .................... 96

12. Maximum rates of discharge for Indicated periods and excesa of peak discharge (duration 1 minute) over those 

rates in San Dimas and Calleguas Creek Basins, March 2, 

1938 .......................... 131

13. Ratio of maximum discharge for indicated periods to

maximum 24-hour discharge for certain areas In Santa

Ana, San Gabriel, and Los Angeles River Basins ..... 134

14. Characteristics of distribution of area in drainage

basins above certain flood-control dams In San Gabriel

and Los Angelea River Basins .............. 139

15. Topographic characteristics of certain drainage basins 

above point of measurement In Santa Ana, San Gabriel, 

and Los Angeles River Basins .............. 140

16. Runoff characteristics during flood of February-March 

1938 for certain areas in San Gabriel and Los Angeles 

River Basins ...................... 146

17. Maximum rates of rainfall and runoff, In Inchea per hour 

for given periods of time, for certain areas In Santa 

Ana, San Gabriel, and Los Angeles River Baains ..... 150

18. Duration, In hours, and rates of runoff, in Inches per 

hour, for given rates of precipitation at typical stations in the San Gabriel and Los Angeles River Basins. . 157

19. Ratios of maximum rates of precipitation and runoff for 

given periods to those for maximum 24-hour period for 

certain areas in San Gabriel River Basin ........ 157

20. Time of occurrence of center of mass of precipitation,

. center of mass of runoff, and lag between times of occurrence, at typical stations In San Gabriel and Los 

Angeles River Basins .................. 164

21. Precipitation and runoff for given periods on 1/40-acre

plots in Fern Canyon .................. 167

22. Ratio of maximum discharge for indicated periods to the

maximum 24-hour discharge for City and San Dimas Creeks

aftd for the average for 14 areas in southern California. 180

23. Summary of flood discharges ............... 287

24. Average depth of precipitation, In Inches, required to 

produce runoff on certain streams in the San Diego 

area .......................... 306

25. Net retention In Strawberry and Santa Anita Creek Basins

for the rainy seasons of 1925-26, 1926-27, and 1937-38 . 353

26. Rainfall, runoff, and retention for the period February 

27 to March 10, 1938, for selected streams in southern 

California ....................... 360

27. Storage and flow at reservoirs in Santa Ana, San

Gabriel, and Los Angeles River Basins during floods of 

February and March 1938 ................ 370
X TABUS

Page 

Table 28. Deposition of debris in reservoirs and debris basins of

the Los Angeles County Flood Control District ..... 374

29. Loss in capacity of reservoirs of the LOB- Angeles

County Flood Control District ............. 375

30. Scour and fill in channel of the Santa Ana River due to

flood of March 1938 .................. 379

31. Loss of life in southern California due to storm of

February 27 to March 3, 1938 ............. 388

32. Damage in southern California caused by storm of February

27 to March 4, 1958 .................. 384
FLOODS OP MARCH 1958 IN SOUTHERN CALIPORMIA

Harold C. Troxell and others

ABSTRACT

During the winter of 1937-38 California was visited by two disastrous 

floods, one in December 1937, in the northern part of the State, I/ and 

the other in March 1938, in the southern part of the State. The present 

volume is a report on the flood in the southern part of the State.

A series of heavy rainstorms in the coastal area, extending from San 

Diego on the south to San Luis Oblapo on the north and inland to parts of 

the Mojave Desert, produced extreme floods. These floods, which appear 

to have been the greatest within the last 70 years, caused the loss of 87 

lives and damage estimated at $78,602,000.

The storm seems to have centered in the San Bernardino and San Gabriel Mountain areas tributary to the Los Angeles, San Gabriel, Santa Ana, 

and Mojave River Basins. These mountain areas are among the highest in 

southern California, ranging in altitude from about 1,000 to 11,485 feet 

above sea level. Their average precipitation for the period February 27 

to March 4 was about 22.5 Inches, and the greatest precipitation recorded 

was 32.20 inches at Kelly'a Kamp, in the San Gabriel Mountains between 

Ontario and Cucamonga Peaks, at an altitude of 8,300 feet.

The typical drainage areas within this mountain region are small, 

short, rough, and steep, the average land slope ranging from about 35 to 

65 percent. In much of the region, considerably more than half of the 

average rainfall of 22.5 inches was absorbed In the soil mantle and underlying rock and held in storage at the end of the storm period, notwithstanding the many factors conducive to rapid surface runoff.

The rates of rainfall during the storm period of March 1938 were not 

particularly high as compared with the rates in other storm periods in the 

same region. Only for periods as long as 24 hours do the maximum rates 

of rainfall appear to equal or exceed those of earlier storms. The maximum discharge coming at the culmination of these maximum 34-hour periods, 

produced in some areas a runoff of more than 1,000 second-feet per square 

mile. This report indicates that these high rates of flood runoff occurred at a time when antecedent rainfall had been such as to fill most of 

the space available for subsurface storage.

The relations between rates of rainfall and rates of runoff for the 

24-hour and shorter periods of maximum rainfall as obtained for a number 

of areas controlled by reservoirs are included in this report. Many features incidental to these relations have also been indicated.

In a region marked by the sharp topographic and geologic contrasts 

that exist In seuthern California many factors affect rates of flood runoff. Considered from a broad viewpoint the area consists of a series of 

mountain ranges and intervening valleys, varying in size and altitude, 

that merge into the coastal plain. The mountains represent great upthrust or upfolde"d blocks of the earth's crust, and the valleys are depressed segments filled with debris eroded from the surrounding mountains. 

The surface conditions affecting rates of runoff throughout the mountain 

area range from steep slopes of much-fractured rock overlain by a thin 

soil mantle, interspersed with outcrops of practically'impervious unweathered rock, to almost level surfaces covered by a porous* soil mantle 

and underlain by thick deposits of highly permeable_£lluvium.

The region is geologically young, with erosion proceeding at an active rate within the mountain area. During the flood of March 1938 the 

streams moved down their mountain channels a great quantity of debris, 

much of which had accumulated since the time of previous major floods. 

Measured on an areal basis the debris load in parts of the region exceeded 70 acre-feet per square mile. This movement of debris from the. 

stream channels had the effect of reducing the storage capacity of many 

of the mountain reservoirs as much as 78 percent.

1 HeGlashaa, H. D., and Briggs, R. C., Floods of December 1937 in 

northern California; U. S. Qeol. Survey Water-Supply Paper 843, 497 pp., 

1940.
2 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

INTRODUCTION

During the period February 27 to March 4, 1938, southern California 

was visited "by a series of heavy rainstorms, centered along the coastal 

slopes of the San Gabriel and San Bernardino Mountains, that produced 

flood discharge far in excess of any previously recorded. Although the 

rates of rainfall for short periods were not unusually high, the maximum 

rates for a 24-hour period at many of the mountain stations exceeded any 

within the period of record. According to reports of the Corps of Engineers, United States Army, the resulting floods claimed the lives of 87 

persons and caused damage amounting to $78,602,000.

More information has been available concerning these floods than for 

any of the previous floods in this region because of the concern that had 

developed among the residents in matters pertaining to flood control and 

conservation of water. Records were obtained from approximately 730 precipitation stations, of which about 70 were equipped with recording gages. 

The flood runoff, or the maximum discharge, has been determined at about 

160 places in southern California. Difficulties involved in obtaining 

satisfactory records of runoff in the mountain area have made it necessary to compute a part of these records on the basis of the relation of 

runoff to rainfall. The basic factors in this relationship were determined mainly from the records obtained during the flood period at a group 

of flood-control, reservoirs in Los Angeles County. Much information on 

the movement of debris down the channels of steep mountain streams was 

obtained at each of these reservoirs as well as at a group of debris 

basins, and some of it is included in this report.

In order to compile and make available to the general public data 

obtained during this flood period, the President of the United States on 

May S3, 1933, approved the allotment of the sum of $3,779 by the Works 

Progress Administration to the Geological Survey, United States Department 

of the Interior. In June 1938, the Public Works Administration, acting 

in accordance with the National Industrial Recovery Act of 1938, allotted 

to the Geological Survey the sum of $21,000 to assist in the preparation 

of the present report, which embodies these data.

ADMINISTRATION AND PERSONNEL

The field and office work incident to the preparation of this report 

were performed by the water-resources branch of the Geological Survey under the general administrative direction first, of N. C. Grover, chief
ACKNOWLEDGMENTS 3

i

hydraulic engineer until his retirement on January 31, 1939; then of C. Q. 

Paulsen, acting chief hydraulic engineer until October 17, 1939; and 

finally of G. L. Parker, chief hydraulic engineer since October 17, 1939. 

Mr. Paulsen has administered the work also as chief of the division of 

surface water;

The actual field work and collection and tabulation of the basic information on stages and discharges and the many other tasks in the preparation of the report were done by the personnel of the Los Angeles suboffice of the San Francisco district office of the division of surface 

water, under the direction of H. D. McGlashan, district engineer.

The activities in the Los Angeles office have been carried on under 

the supervision of F. C. Ebert, senior hydraulic engineer in charge, assisted by Harold 0. Troxell. Mr. Troxell has been largely responsible 

for the special hydraulic and hydrologic studies that have contributed to 

the preparation of the report. The manuscript was reviewed by W. Q. Hoyt, 

consulting engineer, of the conservation branch of the Geological Survey. 

The final assembling and arranging of the report was carried on under the 

direction of R. W. Davenport, chief of the division of water utilization. 

Many of the members of the Geological Survey staff have participated in 

the collection and preparation of the information embodied in the report, 

especially George E. Carroll, R. Stanley Lord, and Kenneth R. Melin, all 

of the Los Angeles office. E* V. Peterson, also of the Los Angeles office, 

prepared the section entitled "Physiographic and geologic features affecting flood runoff". Much of the tabulation and typing necessary for the 

report was done as project 365-03-3-34 of the Works Progress Administration, under the direction of Herbert C. Legg, administrator for southern 

California, and Edwin B. Scheuer, coordinator of research, surveys, and 

statistical projects. In carrying on this work the permanent field and 

office staffs were assisted by temporary employees appointed by the Secretary of the Interior under the provisions of the National Industrial Recovery Act*

ACKNOWLEDGMENTS

The Corps of Engineers, United States Army, through Maj. Theodore 

Wytnan, Jr., district engineer, Los Angeles, Calif., made available, for 

use in this report, information collected by that organization on the 

floods of March 1938,data on historic floods, flood damage, flood runoff, 

and precipitation, and photographs. The Los Angeles County Flood Control 

District, through H. E. Hedger, chief engineer, furnished most of the
4 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

precipitation records for that county and detailed records of operation of 

the reservoirs and of silt deposition in the reservoirs and debris basins. 

The Orange County Flood Control District, through M. N. Thompson, chief 

engineer, furnished precipitation and runoff data for the Santa Ana River' 

Basin. The United States Weather Bureau and the Division of Water Resources of the State of California, Department of Public Works, furnished 

data on precipitation. The United States Forest Service furnished data 

on precipitation and runoff collected in the San Dimas Experimental Forest.

Much information was obtained from other sources, including individuals, corporations, and city officials, acknowledgments of which are 

given as far as practicable, at appropriate places in the report.

GENERAL FEATURES OF THE STORM AND FLOOD

The rains that caused the severe floods of March 1958 in southern 

California began with a general light fall on February 27 and during the 

early hours of February1 28. The later hours of February 28 were marked 

by generally intense and continuous precipitation. On March 1 there was 

a lull, followed on March 2 by the heaviest rains of the storm and on 

March 3 by light and intermittent rain, which continued in some places 

through March 4. Although the storm is generally referred to as that of 

February 27 to March 4, it had ceased over most of the area on March 3.

The heavy rains covered the Pacific coast area for about 250 miles 

north of the boundary with Mexico and extended inland 50 to 100 miles. 

(See fig. 1.)

The storm appears to have centered in the San Gabriel and San Bernardino Mountain areas tributary to the Santa Ana, San Gabriel, and Los 

Angeles Rivers. Many of the rainfall records indicated from 20 to 30 

inches of rain during the period February 27 to March 4. The heaviest 

rainfall for this period, 32.20 inches, was observed at Kelly's Kamp, in 

the San Gabriel Mountains between Ontario and Cucamonga Peaks, at an altitude of 8,300 feet. The rainfall decreased sharply to the north and 

south of this area, the recording stations at San Diego and San Luis < 

Obispo showing 4.26 inches and 3.67 inches, respectively. The rainfall 

decreased sharply also toward the Mojave Desert area; at Table Mountain 

(altitude, 7,500 feet)> about 12 miles northwest of Kelly's Kamp, the 

rainfall was 10.40 inches, and at Victorville (altitude, 2,713 feet), 

about 30 miles northeast of Kelly's Kamp, it was 3.16 inches. These records were not typical of the headwaters of the Mojave River, for there
OENERAL FEATURES OF THE STORM AND FLOOD

EXPLANATION

Drainage basins in nbleh 

record-breaking or extraordinary floods

Figure 1.- Map of California showing area covered by this report.
6 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

was a rainfall of 30.49 Inches at Lake Arrowhead and 28.58 inches at Sawpit Canyon.

Daingerfield 2 gives the following account of this storm and the 

antecedent weather conditions:

The season of 1937-38 (beginning July 1, 1937) has been marked by 

wide contrasts in rainfall over southern California. Los Angeles was 

rainless from Hay 31 to October 2, 1937, Inclusive, a period of 125 days, 

followed by 67 days, or until December 8, 1937, with only two light 

showers, totaling 0.03 inch. The combined period of 192 days had only 

0.03 inch of precipitation. This long dry period is second only to that 

of 1927, when no measurable rainfall occurred at Los Angeles for the 197- 

day period from April 13 to October 26, although traces were recorded 

each month. The recent drought was rather definitely ended by the rain 

of December 9-12, 1937, and precipitation was ample and approximately 

normal during the remainder of December and through January, 1938.

The closing days of January, however, were marked by intense disturbances over the Gulf of Alaska and adjacent North Pacific waters, with 

strong southeasterly trends near the Pacific coast of North America, which 

has been absent or deficient in the earlier depressions of the season. 

This change in storm development and movement ushered in a period of almost continuous and frequently heavy rainfall over this area of California 

during the first half of February, during which period the soil became 

well saturated with moisture.

The tendency to form disturbances near and off the Pacific coast 

featured the late January, February, and early March period. A storm 

which developed northeast of Hawaii moved slowly eastward (followed by a 

we11-developed Pacific high) and moved inland near the Bay region on 

February 9. This was an exceptionally violent disturbance, attended by 

precipitation throughout California, heavy over the northern part of the 

State, and high winds and gales over most coastal districts and inland to 

and beyond Sacramento.

A series of North Pacific and Gulf of Alaska depressions prevailed 

from February 26 to March 4, 1938, extending their maximum sphere of influence hundreds of miles farther southeastward than normally over the 

Pacific coast area. On February 27, a rather shallow disturbance moved 

slowly in over the southern XJalifornia coast, attended by a general light 

rain on the 27th and intermittently through the 28th. During the night 

of February 28-March 1, heavy rain occurred as the result of the passage 

of a cold front, which moved in from the northwest. No general rain occurred after this frontal passage until March 2, with the arrival of a 

more intense disturbance. This disturbance likewise developed northeast 

of the Hawaiian Islands, and while the center moved to the Oregon coast, 

the region of greatest intensity was over southern California. Warmfront action and a pronounced orographic effect produced the greatest intensities and amounts of precipitation of the entire storm period, which 

were directly the cause of the great flood.

The origin of the storm is briefly described in a report of the Corps 

of Engineers, United States Army, 3 as follows!

The storm, or rather series of storms, which caused the flood of 

March, 1938, originated in Siberia, circled southward over the Pacific 

Ocean to Midway Island, swinging eastward near Hawaii, and thence to the 

California coast. In their long, encircling course over the Pacific 

Ocean, a great amount of moisture was absorbed. Reaching southern California, the air masses swept in at high speed at almost right angles to 

the main mountain ranges. As the moist air was thrust upward by these 

obstructions, it encountered the colder upper air. The rapid condensation resulting caused excessively heavy rainfall.

2 Daingerfield, L. H., Southern California rain and flood, February 

27 to March 4, 1938: Monthly Weather Rev., vol. 66, no. 5, p. 139, 1938.

3 Santa Ana River, Calif., flood control, Hydrology of flood of 

March 1938, p. 2, U. S. Engineer Office, Los Angeles, August 1938 (processed).
GENERAL FEATURES OF THE STORM AND FLOOD 7

Discussions of the more intricate features of the synoptic analysis 

of this storm have been prepared by Pierce, of the United States Weather 

Bureau;* Burke, of the Los Angeles County Flood Control District;5 and. 

the staff of the Los Angeles district office, Corps of Engineers, United 

States Army. 6

Die Intensity of rainfall for relatively short periods, although high 

In much of the storm-affected area, was generally less than had been previously recorded, and only in the maxloom rainfall for a 24-hour period 

did this storm exceed most previous storms. In the mountain area, however, the maximum 24-hour precipitation for 1938 apparently has not been 

exceeded during the past 30 years. The storm of March 1938 had many of 

the characteristics of the storm of December 31, 1933, to January 1, 1934, 

sometimes called the "New Year's storm of 1934", which was notable for 

the large amount of flood damage in the La Canada Valley. 7

In the storm of March 1938, the maximum rate of rainfall for a 5- 

minute period was 4.80 Inches an hour, as recorded by a rain gage in the 

Rossmoyne fire area in the Verdugo Mountains near Glendale. The maximum 

rate for a 1-hour period was 1.99 inches at Clear Creek, in the San Gabriel Mountains.

The main streams affected by this storm were the San Diego, San Luis 

Rey, Santa Margarita, Santa Ana, San Gabriel, Los Angeles, Santa Clara, 

Ventura, Santa Ynez, and Santa Maria Rivers. (See fig. 2.) The basins 

of the Santa Ana, San Gabriel, and Los Angeles Rivers and parts of that 

of the Santa Clara River contributed the greatest flood runoff. Profiles 

of the Santa Ana and San Gabriel Rivers and their main tributaries are 

shown in figures 3 and 4.

The "flood runoff from the storm of March 1938 was especially heavy 

in the larger streams in the mountains and in the main streams crossing 

the valley floor. It is believed that the peak discharges over a considerable part of the area exceeded any since those of the floods of 

1861-62, which are generally accepted as the greatest previously known In 

the region. Of the more recent floods for which there are records of discharge, those of 1914 and 1916 rank as having the highest peaks prior to 

1938.

4 Pierce, C. H., Synoptic analysis of the southern California flood 

of March 2, 1938: Monthly Weather Rev., vol., 66, no. 5, p. 135, 1938.

5 Burke, M. F., Flood of March 2, 1938, Los Angeles County Flood 

Control District, May 20, 1938 (processed).

6 Los Angeles County drainage area, Calif., Report on engineering 

aspects, flood of March 1938, U. S. Engineer Office, Los Angeles, August 

1938 (processed).

7 Troxell, H. C., and Peterson, J. Q., Flood in La CaKada Valley, 

California, January 1, 1934: U. S. Geol. Survey Water-Supply Paper 796-C, 

pp. 53-98, 1937.

454720 0-42-2
Figure 2.- Map of area covered by this report showing princi
Elevation, in feet

 9

*r

Santa Ana River

I I 

Prado gaging station

Chino Creek gaging station

Cucamonga gaging station

San Antonio Creek gag

Warm Creek

gaging station

ytle Creek (east channel) gaging st

Santa Ana River near San Bernardino 

Strawberry Creek gaging station

Cajon Creek 

gaging station

Mentona gaging station

i i i 

Hill Creek gaging

Lone Pine Creek 

gaging station

Lone Pine-Cree
Elevation,in feet

Spring Street, near Los 

San Gabriel River at

San Gabriel River at

lawpit Creek near Monrovia 

Fish Creek near Duarte

San Gabriel River at Morris Dam

San Dimas Creek at flood-control

i i i 

an Dimas Creek

North Fo

San Gabriel River

near Camp Bonita

River at 

dam No.

Fork of 

~| 

'Pra
GENERAL FEATURES OF THE STORM AND FLOOD 11

The Santa Ana, San Gabriel, and Los Angeles River systems drain the 

most highly developed areas of southern California: practically all the 

arable land from the mountains on the north to the ocean on the south is 

occupied by farms, orchards, and towns. When the floods were at their 

highest, generally during the afternoon of March 2, water and debris 

poured from the steep mountain canyons and spread over much of the land 

bordering the streams. Areas near the mountains were covered with debris 

and extensive tracts along the lower courses of the streams were Inundated. (See pis. 1 and 2.)

During the period February 27 to March 3 the total direct flood runoff from the mountain areas, In mean depth in inches, ranged from less 

than 1 Inch to more than 13 Inches. Rates of maximum discharge ranged 

from 200 to 600 second-feet per square mile andr were estimated to be as 

high as 1,000 second-feet per square mile In some places. The streams 

flowing In the steep, narrow canyons moved enormous quantities of debris 

and greatly disturbed jbhe material in the bottom of the canyons. The 

damage In the canyons, however, where the population is sparse, was small 

In comparison with that on the outer slopes and floors of the valleys.

The area centering at Colton, where Warm and Lytle Creeks join the 

Santa Ana River, was extensively overflowed (see pi. 3); and parts of the 

cities of San Bernardino and Riverside were also submerged. Above the 

city of Santa Ana, where breaks occurred in the levees (see pi. 4), large 

areas were inundated and some of the floodwater entered an old river 

channel and damaged many homes and orchards. (See pis. 5 and 6.) This 

spreading of the floodwaters above the city of Santa Ana reduced the peak 

discharge at that place to about half the peak at the Orange-Riverside 

County line, about 18 miles upstream.

At the stream-measurement station on Santa Ana River near Mentone, a 

peak discharge of 52,300 second-feet occurred during the flood of March 

1938, as compared with a peak discharge of 29,100 second-feet on January 

27, 1916.

On the San Gabriel River the flood was the greatest of record, notwithstanding the large storage capacity of San Qabriel No. 1 and Morris 

Reservoirs, on the main stream, and additional regulation on tributaries. 

Much of the floodwater of the San Gabriel River flowed into the Rio Hondo 

soon after leaving the mountains and thence Into the Los Angeles River 

near Downey. Comparatively little damage was done along the lower reaches 

of the San Gabriel except in an area near the ocean and along Coyote 

Creek.
12 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

At San Gabriel River flood-control dam No. 1, on the San Gabriel 

River about 3& miles above the Geological Survey's stream-measurement 

station near Azusa, the partly regulated peak discharge on March 2, 1938, 

was about 90,000 second-feet as compared with an unregulated peak discharge of 40,000 second-feet at the gaging station near Azusa on January 

18, 1916.

On the Los Angeles River the flood of March 1938 exceeded all previous floods for which records are available. Facoima and Tujunga Creeks, 

Arroyo Seco, and other tributaries reached unusually high stages. The 

highly developed areas along the Los Angeles River and its tributaries in 

the city of Los Angeles sustained the greatest damage. (See pi. 7.)

3

Large tracts in San Fernando Valley were inundated, and bridges, highways, 

and railroads were severely damaged. (See pi. 8.) The flow from Rio 

Hondo added considerable water to the Los Angeles River below Los Angeles 

and increased the peak flow at the city of Long Beach, although comparatively little damage was done to that city. At a point a mile upstream 

from the Main Street Bridge in Los Angeles, above the Arroyo Seco, the 

discharge of the Los Angeles River was about 67,000 second-feet, as compared to an estimated discharge of about 31,100 second-feet at the Main 

Street Bridge during the flood of January and February 1914.8 During the 

storm of March 1938 the flood-control reservoirs on Pacoima and Tujunga 

Creeks and Arroyo Seco were filled to capacity and undoubtedly contributed 

somewhat to the regulation of the discharge.

In the Santa Clara and Ventura River Basins the flood runoff exceeded 

the maximum of record in many localities. The flood on Santa Clara River 

did considerable damage to the Southern Pacific Railroad in Soledad Canyon and to citrus groves and several highway bridges in the Santa Paula 

area. The maximum discharge of the Santa Clara River at Santa Paula on 

March 2, 1938, was about 120,000 second-feet. The maximum discharge of 

the Ventura River near Ventura was 39,200 second-feet, as compared with 

the previously recorded maximum of 23,000 second-feet on December 31, 

1933.

The maximum discharge of the Santa Ynez River near Lompoc was "bout 

50,100 second-feet on March 3, 1938, as compared with 41,800 second-feet 

on January 25, 1914.

8 Prom reports of the Board of Engineers, Flood Control, Los Angeles, p. 248, July 27, 1915.
QBSBRAL PSATURBS OF THE STORM AND FLOOD 13

In the Mojave River and Rock Creek Basins record-breaking floods resulted from the heavy rains that fell on the north slopes of the San Gabriel and San Bernardino Mountains. As these streams flow onto the Mojave Desert, in the Great Basin, little damage was done except to highways and the railroad in the vicinity of Victorville, Barstow, and Yermo.

In the remainder of the area covered by the storm, the maximum discharges of the streams during the flood of March 1938 were not of major 

proportions and have been exceeded several times during the period of record.

Flood stages are most keenly felt by occupants of a flooded area 

when the safety of their lives or homes is menaced. The manner in which 

man has challenged nature on sane of the streams of southern California 

is conspicuous. Streams that formerly meandered freely over debris cones 

and valley floors are now restricted to narrow channels (see pi. 9), 

fixed by the ever-encroaching developments of a rapidly increasing population. It seems probable that much of the flood runoff from the mountains that formerly was absorbed by the very porous gravel cones, built 

to a thickness of many hundreds of feet by flood debris, now moves rapidly, through concrete storm drains, across the debris cones and the 

naturally absorptive valley floors. The older river channels that carry 

the runoff to the ocean are now taxed beyond their capacities by concentrated flows. For these reasons, it is no doubt true that storm rainfalls of no greater intensity are considerably more disastrous, in many 

areas, under present conditions than under former conditions. The covering of absorptive oones and valley floors with houses and streets, the 

construction and other surficial changes in mountain areas, and the 

changes in land cover due to fires and other causes may all change, 

within a comparatively short time, the runoff characteristics of a drainage basin, especially in an area as young geologically as southern California. The evaluation of these influences on the runoff from the March 

storm seems beyond the limits of conjecture.

During the floods of March 1938 houses, both large and small, were 

destroyed (see pi. 10), and highways, bridges, and many other public improvements were washed away or damaged. Citrus groves along the Santa Ana 

River were overflowed, and large losses resulted. More than 290,000 acres 

of land was inundated in Los Angeles, San Bernardino, Orange, Riverside, 

and Ventura Counties. Owing to the rapidity with which the flood waters 

collected in the river channels there was not sufficient time to warn 

many of the residents in the threatened areas. As a result, 87 lives were
14 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

lost, mainly along the Santa Ana and Los Angeles Rivers, and many people 

were driven from their homes. The property damage caused in southern 

California by the floods is estimated by the Corps of 'Engineers, U. S. 

Army, at about (78,602,000.

COLLECTION OF RAINFALL AND RUNOFF RECORDS

As the floods of March 1958 in southern California were extraordinary 

in respect to loss of life and property damage, special effort has been 

made to collect and compile in this report all available information relating to meteorologic conditions that may have had a bearing on their 

magnitude and other characteristics. Likewise, an attempt has been made 

to present all available stream-flow records during the flood period, including estimates of peak discharges. Concerning the adequacy of the Information obtained, the Corps of Engineers 9 summarizes the difficulties 

encountered by the various fact-finding agencies as follows:

Notwithstanding the great amount of hydrological data collected, results have been disappointing in many respects, principally due to the 

lack of direct measurements of discharge during the peak period. The 

streams in this area produce floods of exceedingly short duration. The 

rapidly changing stages do not allow sufficient time for the collection 

of necessary data. Transportation is disrupted to a great extent. Waterstage recorders, in many cases, were damaged or destroyed before the peak 

arrived. Bridges from which discharge measurements were made during the 

lower stages were swept away. Current-meters were damaged or lost because of the debris and high velocity of flow. Surveys to determine fill 

or scour were, in many cases, rendered valueless because of the lack of 

data concerning the conditions of the stream bed before the flood. Information was missing in some cases as to just where the channels were at 

the time of the peak.

At many river-measurement stations maintained by the Geological Survey, it has been necessary to fill in incomplete records by a comparison 

of observations in a given basin wi-th observations in adjacent basins; by 

surveys and studies of cross sections and slopes of stream channels; and 

by the conversion of rainfall into runoff by means of such relationships 

as could be determined in basins for which continuous records are available. Throughout this report an endeavor has been made to indicate 

clearly the source of the data and the methods used in deriving such results as are not based on actual observations or arrived at by standard 

methods. The publication, so far as practicable, of all the base data 

obtained will enable engineers to judge as to the reasonableness of the 

assumptions and to make independent studies of the records. Flood runoff data are included in this report for all localities indicated on 

plates 11, 12, and 13.

9 Los Angeles County drainage area, Calif., Report on engineering 

aspects, flood of March 1938, U. 3. Engineer Office, August 1938 (procqssed).
GEOLOGICAL SURVEY WATER SUPPLY PAPER 844 PLATE 1

Hwy-IOI I- P.E.Ry. V

I

MOUTH OF SANTA ANA RIVER, MARCH 3, 1938.

Figures along channel represent distance in miles from Pacific Ocean. Courtesy of Fairchild Aerial Surveys, Inc.

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 2

A'NA ;RIVER VERFLOW

OVERFLOW AT MOUTH OF SANTA ANA RI\ ER, SHOWIN G AREA BETWEEN SANTA ANA RIVER AND HUNTINGTON BEACH SUBMERGED ON MARCH 3,1938.

Courtesy of Fairchild Aerial Surveys. Inc.

GEOLOGICAL STJEVEY WATEE-SUPPLY PAPER 844 PLATE 3

DEBRIS DEPOSITS IN COLTON. 

Damage caused by flood runoff of Lytle Creek.

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 4

BREAK IIN LEVEE OF SANTA ANA RIVER, MARCH 3, 1938.

Figures along channel represent distance in miles from Pacific Ocean. Courtesy of Fairchild Aerial Surveys, Inc.

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 5

i

ORANGE

OVERFLOWED LAND ALONG SANTIAGO CREEK.

Flooded citrus and walnut groves near Orange and Villa Park. Courtesy of Fairchild Aeria Surveys, Inc.

6 PLATE 844 PAPER WATER-SUPPLY SURVEY GEOLOGICAL 

B.

GROVE. CITRUS OVERFLOWED IN DEPOSITS DEBRIS 
7 PLATE 844 PAPER WATER-SUPPLY SURVEY GEOLOGICAL 

RIGHT-OF-WAY. RAILROAD ON WASH-OUT 

CHANNEL. TO DAMAGE B. 

ANGELES. LOS NEAR RIVER ANGELES LOS ON SCENES 
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 8

SAN FERNANDO VALLEY, MARCH 2, 1938.

Note small, meandering channel in right center. Courtesy of 115th Photo Section, California National Guard.

GEOLOGICAL SURVEY W A.T.K.K-S U ififii K f Af£jK o'-it i-LI AM Hi a

A. OUTLET CHANNEL FROM DUNSML1R DEBRIS BASIN. B. OUTLET CHANNEL FROM EAGLE-GOSS DEBRIS BASIN.

ARTIFICIAL CHANNELS ACROSS DEBRIS CONES, MARCH 2, 1938.

Note waves in the flood runoff. Courtesy of Corps of Engineers, U. S. Army.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 10

A. DESTRUCTION BY MEANDERING STREAM. 

Note composition of stream banks.

B DEBRIS DEPOSITED BY MEANDERING STREAM. 

Note that deposit is as high as fence at front of house but much lower at rear

PROPERTY DAMAGED BY FLOOD.

Courtesy of Ralph Willis.
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 15 

METEOROLOGIC AND HYDROLOQIC CONDITIONS 

Precipitation records

In the arid and semiarid climate of southern California rainfall is 

a dominant factor in the life of the people, and the collection of data 

on precipitation is, therefore, of great importance and public interest.

Many governmental agencies furnish data on rainfall to supplement those

\ 

collected by the United States Weather Bureau. Among these ageneiea are

the Forest Service and Soil Conservation Service of the Halted States Department of Agriculture; Corps of Engineers, United States Army; California State Division of Water Resources; Los Angeles County Flood Control 

District; Orangj County Flood Control District; Ventura County Engineer; 

and Los Angeles City Water Department. In addition to the establishment 

of their own stations, these agencies have aided in furnishing gages to 

individual's for operation in sparsely populated areas where no precipitation records were available. Many rain gages have also been operated by 

private individuals and by cities and towns for their own Information. 

Some of these records may be subject to error in interpretation, owing to 

faulty location of gages or topographic influence, but generally information thus collected makes a substantial contribution to the knowledge of 

precipitation in the area. As a result of this widespread activity and 

Interest, southern California has a more complete coverage of precipitation stations than most other sections of the United States.

The floods of March 1938 were the direct result of rain which fell 

during the storm period February 27 to March 4. The daily precipitation 

data for this period are presented in table 1, which embodies the records 

at 733 standard rain-gage stations in the region covered by this report 

in which direct observations were made of the accumulated catch. The 

stations are arranged alphabetically in 22 groups corresponding to areas 

defined by drainage basins or other topographic features. For each sta*- 

tlon are given the location, altitude, daily rainfall, total rainfall for 

the storm period, name of observer or source of the record, and a note 

concerning time of observation if other than in the aftern6on. The latitude and longitude of each station are recorded to the nearest minute, or 

to the nearest second if the close spacing of the gages in an area makes 

this desirable or if already so determined. Altitudes were obtained from 

topographic maps of the Geological Survey and are accurate within 10 to 

100 feet, depending on the contour interval of the maps. Small amounts 

of rainfall observed at some stations on February 26 and March 5 were 

combined with amounts recorded on February 27 and March 4, respectively in 

order to complete the record for the entire storm.
Table 1.- Daily precipitation, in inches, at standard gagas for the perio

(Measured in the afternoon exoept as noted)

Station

Tia Juana, Otay, and Swectwater River Basins

Barret t Dam**

Bonita**

Camp Denny«*

Campo**

Chollas Heights Reservoir«»

Chula Vista, Western Salt Works

Chula Vista, 270 Madrona Street

Coronado, First and D Streets

Descanso ranger station

Dulzura**

Dulzura Summit**

Froatless Acres**

Judaon Reservoir**

Morena Dam**

National City, 916 National Avenue

Pine Valley, Cottonwood Ranch**

Point Lama**

Savage Dam**

South Basin treatment plant**

Sweetwater Lake**

Viejas Valley**

Willows **

San Diego and San Dieguito River Basins

Alpine

Bernardo Bridge**

Cuyamaca Dam**

Del Mar**

Enoinitas, 0.3 mile east of railroad station

Latitude

0 | II

32 40 45

32 39 15

32 47 45

32 35 45

32 43 35

32 36 15

32 38 15

32 41 45-

32 51 00

32 58 15

32 37 00

32 45 00

32 37 00

32 41 00

32 40 30

32 44 30

32 40 10

32 36 30

32 33 00

32 41 30

32 51 15

32 50 00

32 50

33 03 30

32 59 15

32 58 45

33 02 30

Longl tude

0 | II

116 40 15

117 02 30

116 45 00

116 28 30

117 04 30

117 05 45

117 05 00

117 10 30

116 37 15

116 46 30

116 45 45

116 54 00

117 03 30

116 33 00

117 06 30

116 29 00,

117 14 30

116 55 45

117 05 15

117 00 30

116 42 00

116 43 15

116 46

117 04 15

116 35 15

117 15 30

117 17 15

Altitude 

(feet)

1,650

110

1,360

2,543

375

9

75

30

3,400

1,100

1,458

550

235

3,050

50

3,200

302

500

25

310

2,400

2,175

1,850

370

4,677

50

150

February

27

0.62

.52

1.22

1.04

.55

.97

.50

.68

.46

.69

.86

.65

.56

.92

.49

2.19

.67

.64

.91

.55

.45

.38

1.28

.36

.89

.44

.40

28

1.60

.34

1.06

.71

.70

.93

.36

.42

1.42

1.32

.87

.92

.34

1.46

.36

.79

.55

.47

.26

.40

.95

.85

.40

1.65

2.67

.58

.97

1

1.32

.92

.67

.75

1.06

.38

.84

.83

1.45

1.25

1.44

.80

.84

1.31

.52

.82

.82

.96

.78

.75

1.14

1.30

1.05

1.50

2.46

1.02

1.37
Escondldo, 755 West Third Street

Escondido** 

El Cajon, near Main Street and Johnson 

Avenue **

El Cajon** 

El Capitan Dam**

Grossmont, Eucalyptus Reservoir**

Hodges Dam** 

Julian 

Julian 

La Jolla, Pearl and Cuvier Streets**

La Mesa, Spring Street** 

Lake Wohlford** 

Lockwood Mesa** 

Mesa Grande 

Mesa Grande, post office

Miramar, Scripps Ranch 

Mission Valley, near Grantville School** 

Monte pumping plant** - i

Murray Dam** 

Pacific Beach at mouth of Rose Canyon**

Ramona 

Rancho Santa Fe, civic center** 

San Diego River diverting dam**

San Diegulto Dam** 

Santa Ysabel, post office

Scott Ranch near Encinitas 

Scripps Institute of Oceanography, La Jolla* 

State College, San Diego** 

Wynola, Spencer Valley

33 06 45

33 08 45 

32 47 30

32 47 30 

32 53 00

32 46 45

33 02 30 

33 04 

33 05 30 

32 50 15

32 46 00 

33 10 15 

32 59 00 

33 12 30 

33 10 45

32 54 00 

32 48 30 

32 52 00

32 46 45 

32 48 30

33 02 30

33 01 45 

32 58 15

33 02 15 

33 06 30

33 03 45 

t 32 51 30 

32 46 30 

33 05 30

117 05 20

117 04 30 

116 58 30

116 55 30 

116 48 15

117 00 15

117 08 00 

116 38 

116 37 00 

117 16 45

117 01 15 

116 59 45 

117 15 00 

116 47 30 

116 46 00

117 06 00 

117 05 30 

116 53 30

117 02 45 

117 13 15

116 51 45 

117 10 15 

116 44 15

117 12 00 

116 40 30

117 15 15 

117 15 30 

117 04 15 

116 38 30

650

750 

480

560 

550

700

350 

4,000 

4,250 

75

550 

1,450 

200 

3,450 

3,250

660 

100

439

500 

30

1,435 

200 

80S

250 

2,983

100 

25 

450 

3,750

.44

.40 

.51

.56 

.35

.55

.43 

1.45 

3.50 

.65

.53 

.20 

.48 

* 

3.00

1.80 

.53

.43

.43 

.54

* 

* 

.30

.40

*

1.35 

.51 

.57

*

2.25

2.04 

1.26

.87 

1.38

1.17

1.75 

.38

* 

.49

1.08 

3.20 

.72 

6.60 

1.00

.45 

.90 

1.10

.86 

.65

2.20 

1.34 

1.70

1.12 

3.02

.47 

.42 

1.25 

2.75

1.75

1.65 

1.12

1.31 

1.31

1.38

1.59

* 

* 

.94

1.30 

2.20 

1.10

* 

2.00

1.35 

.90 

1.31

.83 

.83

* 

1.32 

1.33

1.40 

1.63

1.17 

.71 

1.04

*

 Included In next measurement. 
Table 1.- Daily precipitation, in inches, at standard gages for the period Feb

(Measured in the afternoon except as noted

Station

San Lul3 Rey and Santa Margarita River Basins

Anza

Anago

Carlsbad**

Deluz

"E" Reservoir

Eecondldo canal intake**

Fallbrook **

Fallbrook

Henahaw Dam**

Kelly Ranch near Carlsbad

Oceanside, Third and Tremont Streets**

Oceans ide**

Pala

Pala, 4 miles west of**

Fauba Ranch, station C»»

Pechstein Reservoir**

Red Mountain Ranch**

Rlnoon **

San Clemente

Santa Margarita Ranch**

Santa Rosa Ranch

Valley Center**

Vista

Vista**

Warner Springs**

Allso and San Juan Caplstrano Creek Basins

Allso project, Whiting Ranch

El Tore Civilian Conservation Corps camp **

El Tore, 5 miles northeast of

51 Tore, li miles southwest of

El Toro, 6 miles northeast of

Latitude

'

33 30

33 17 00

33 09 45

33 26

33 12 45

33 16

33 22 30

33 23

33 14 15

33 09 00

33 11 30

33 12 30

33 22

33 20 45

33 28 45

33 11 00

33 23 15

33 17 15

33 25

33 18 30

33 30 30

33 14 30

33 15 15

33 12 00

33 17

33 39 55

33 38

33 39 45

33 36 30

33 39 45

Longitude

,

116 51

116 51 30

117 20 15

117 20

117 12 30

116 53

117 15 -30

117 12

117 46 00

117 18 00

117 23 00

117 20 30

117 05

117 08 00

117 06 00

117 10 45

117 11 45

116 57 00

117 37

117 20 30

117 15 15

117 00 15

117 11 30

117 14 30

116 38

117 40 45

117 41

117 35 15

117 42 00

117 34 00

Altitude 

(feet)

2,600

2,715

192

400

750

1,986

700

700

2,702

50

50

300

400

300

1,000

840

925

1,100

135

80

1,800

1,600

350

330

3,165

444

440

1,000

375

1,100

February

27

0.36

*

.52

5.63

1.86

2.00

*

4.07

.28

1.55

.90

.62

*

*

*

1.50

3.65

.18

.57

*

3.79

.33

1.65

.40

.21

.63

.28

.20

M

.30

28

0.98

1.84

1.40

#

1.61

2.30

3.52

.30

2.89

.55

1.40

1.79

1.37

1.96

1.94

1.30

2.40

.04

.60

2.70

7.20

1.54

.82

2.10

1.21

1.12

1.06

*

M

1.00

1

0.66

2.00

1.65

2.95

.80

.61

2.30

2.17

2.42

1.73

2.00

2.17

1.25

1.39

2.02

.60

2.10

.43

1.64

1.98

3.45

1.94

1.51

1.83

1.36

1.89

1.63

3.42

1.48

2.30
Hare and Starr Ranch, Bell Canyon

Laguna Airway station, Laguna Beach

Moro Ranch, It-vine, Oo,«*

San Juan Capiatrano, t olle north of**

San Juan Capiatrano, on Ortega Highway 1.65

miles from

Trabueo Civilian Conservation Corps camp**

Santa Ana. San Oabriel. and Los Angeles

River Uasiss

San Gabriel Mountains

Altaeanyada, 6268 Linda Vista Drive

Altadena, 2780 Page Drive

Altadena, 166 Bast Foothill Boulevard

Altadena, 1860 Alien Drive

Altadena, 576 Sacramento Street

Altadena, Ventura Street

Arroyo Seeo Canyon, chlorine plant

Arroyo Seco patrol station, 352 Michigan

Avenue

Arroyo Seco ranger station

Bear Creek, West Fork of San Gabriel River

Bennett Ranch near Lytle Creek

Briggs Terrace, Piokens Canyon a/

Browns Flat

Brydon Ranch, north end of Wheeler road

Camp Baldy, San Antonio Canyon _§/

Camp Rincon, West Fork of San Gabriel River

Chilao, 1 mile north of Heweomb RancTi a/

Claremont, Indian Hill Road

Clear Creek, 1.6 miles above Junction with

Tujunga Creek £/

Colby Ranch, Tujunga Creek

33 38 15 .

33 32

33 33

33 31

33 31

33 38 30

34 13 30

34 11 15

34 11 45

34 11 30

34 11

34 11 30

34 12 30

34 Ig 00

34 13 20

34 14 30

34 10 15

34 14 15

34 11

34 09

34 14 15

34 14 30

34 20 31

34 07 30

34 16 37

34 18 27

117 33 45

117 46

117 49

117 40

117 38

117 39 00

118 12 45

118 07 00

118 08 30

118 06 30

118 08

118 09 30

118 10 00

118 11 15

118 10 40

117 53 10

117 27 15

118 13 30

117 43

117 45

117 39 15

117 51 15

117 59 30

117 43 00

118 10 15

118 06 55

1,150

205

' 100

' 103

150

1,000

1,915

1,330

1,345

1,360

1,125

1,179

1,150

1,155

1,530

i;eoo

1,750

2,310

4,300

1,680

4,320

1,500

5,585

1,405

3,100

3,300

.31

.98

.50

.30

.36

.25

*

1.51

1.86

1.47

1.61

1.53

1.37

1.65

1.26

1.90

*

1.18

*

1.10

1.16

1.39

3.42

.88

1.34

1.97

1.32

.61

1.62

1.13

1.28

1.20

3.35

3.50

2.75

3.70

2.84

2.48

2.75

2.83

2.62

4.52

5.50

3.36

*

2.13

3.73

3.89

.70

1.81

3.39

1.55

4.03

1.44

1.12

1.77

1.99

2.19

3.46

2.65

2.18

2.70

2.50

2.34

2.70

3.23

2.62

3.52

2.15

3.15

*

2.31

3.56

2.65

2.20

1.94

3.61

2.23

 Included la next measurement. Measured In the morning. M Record missing
Table 1.- Daily precipitation, in inches, at standard gages for the period F

(Measured in the afternoon except as note

Station

Santa Ana, San Gabriel, and Los Angeles

River Basins Continued

San Gabriel Mountains Continued

Crystal Lake, West Pine Flat

Crystal Lake, East Pine Flat a/

Cu«UBon$a , Highland Avonue , Lewis and ling Ranch

Dalton flood-control dam

Dalton Creek ranger station, at junction of

Volfe and Bell Canyons

Deer Park, 1.5 miles above Sawpit Dam

Devils Gate flood-control dam

Eaton debris dam

Eaton Canyon, at mouth

Echo Mountain

Fish Canyon, at U. S. Geological Survey

gaging station

Glendora, mouth of Englewild Canyon**

Haines Canyon, gravel pit

Henninger Flats . Mount Wilson toll road a/

Hermann, 11332 Osborne Avenue

Hoegee's camp, West Fork of Santa Anita

Creek a/

Kelly 1 s Kamp, 1.25 miles northeast of

Ontario Peak

Kiener Ranch

Kinneloa Ranch, east side of Eaton Wash

La Canada, 4620 Commonwealth Avenue

La Canada, 4874 Commonwealth Avenue

La Crescenta, 2908 Foothill Boulevard

La Crescenta

Little Cienaga, 1 mile north of Coldbrook

Camp

Little Tujunga.

Latitude

34 18 50

34 19 10

34 10

34 10 00

34 11 00

34 12 00

34 10 50

34 10 10

34 11 30

34 12 45

34 10 15

34 09 22

34 15 45

34 11 30

34 16 30

34 12 30

34 14

34 18 30

34 10 45

34 12 45

34 12

34 14 30

34 14 30

34 18 30

34 19 30

Longitude

117 50 45

117 50 45

117 37

117 48 45

117 48 36

117 57 30

118 10 30

118 05 30

118 06 20

118 07 15

117 55 45

117 50 00

118 16 45

118 05 15

118 23 00

118 02 30

117 36

118 24 00

118 05 00

118 12 00

118 12

118 14 30

118 14 15

117; 50 00

118 20 00

Altitude 

(feet)

5,370

5,740

2,500

1,575

1,950

2,500

1,100

900

1,325

3,250

1,050

1,200

2,250

2,650

1,120

2,750

8,300

1,375

1,400

1,275

1,350

1,565

2,264

j 4,850

1,700

February

27

1.65

1.72

.46

1.29

*

1.04

1.31

1.46

1.48

1.78

1.36

2.59

1.20

1.30

.68

1.71

1.80

.72

1.54

1.48

1.55

1.21

1.18

1.55

.83

28

5.02

5.05

2.54

3.64

6.18

3.68

2.38

2.83

3.53

1.80

1.28

1.48

2.58

4.03

1.20

7.82

3.05

1.62

2.07

2.88

3.20

3.35

3.76

4.17

1.48

1

3.3

3.3

2.4

3.3

.6

2.8

2.3

2.4

2.7

2.8

4.3

2.9

2.2

3.1

1.4

4.0

4.0

1.6

2.0

2.5

2.6

3.0

3.0

3.3

1.6
Live Oak Canyon, 4055 North San Antonio

Avenue 

Live Oak Canyon near dam

Loomis Ranch, near Junction of North and

Middle Forks of Alder Creek a/ 

Lopez Canyon at mouth**

Lower Haines Canyon near U. S. Gsological 

Survey gaging station

Lytle Creek at powerhouse intake

Lytle Creek ranger station**

Lytle Creek at powerhouse

Mira Monte Reservoir, at foot of Mount

Wilson trail, Sierra Madre 

Monrovia Canyon

Monrovia Falls, Monrovia Canyon a/ 

Morris Dam, San Gabriel Canyon 

Mountain Springs Ranch, San Dimas Canyon 

Mount Gleason ji/

Mount Wilson ja/

Oakwilde Resort, Arroyo Seco Canyon 

Opid's camp, Wtest Fork of San Gabriel

River a/ 

Pacoima Canyon

Pacoima flood-control dam a/ 

Padue Hills, 1.5 miles north 

Road

Pasadena

Pickens Canyon a/

Pickens debris "Basin

Prairie Forks, 2 miles east of Vincent

Quleh 

San Antonio guard station &/

San Antonio Canyon, 1.25 miles southwest

of Camp Baldy 

San Antonio Canyon at mouth

Santa Anita Canyon ranger station

Santa Anita flood-control dam

San Dtmas Experimental Forest, Bell-Volfe a/

 Included in next measurement.

of Base Line

34 07

34 08 00

34 21

34 17

34 16 15

34 14

34 16

34 12 15

34 10

34 10 00

34 11 15

34 11

34 08 50

34 22 26

34 13 20

34 14 45

34 15 15

34 21

34 20

34 08 45

34 10 40

34 15 15

34 13 15 

34 20

34 10 45

34 14

34 10 40

34 50 00

34 11 04

34 10

117 44

117 44 50

118 03

118 24

118 16 30

117 29

117 29

117 27 30

118 03

117 59 45

117 59 00

117 53

117 46 25

118 12 20

118 03 20

118 11 00

118 05 45

118 22

118 24

117 41 50

118 06 10

118 13 00

118 13 45 

117 42

117 40 28

117 40

117 40 35

118 01 05

118 01 11

117 48

1,255

1,420

4,300

1,173

2,250

2,800

2,770

2,225

985

975

1,450

1,210

1,400

5,450

5,850

2,000

4,350

2,200

1,700

1,768

_

4,250 

i Ann J- , OWV

5,680

2,450

4,527

2,500

1,950

1,400

1,880

.97

1.06

1.24

*

1.27

.43

.32

1.75

.53

.26

1.20

1.36

1.11

1.28

2.16

1.60

1.79

.85

.88

*

.95

1.43

*

*

1.38

.98

.47

1.30

1.56

1.84

2.08

.93

1.41

2.70

5.96

4.49

4.10

3.47

3.47

4.74

3.86

1.97

2.10

5.93

3.14

4.89

2.61

1.94

3.04

3.17

3.60

3.35

6.53

3.88

3.34

7.12

4.06

6.38

1.

2.

1.

2.

2.

5.

4.

2.

4.

3.

3.

3.

2.

2.

3.

1.

3.

2.

2.

2.

4.

3.

2.

.

4.

2.

4.

2.

.

«<H(easured In nornlag. M Record miss
Table 1.- Dally precipitation, In Inches, at standard gages for the period 

_________________________(Measured In the afternoon except as no

Station

Santa Ana, San Gabriel, and Los Angeles

River Basins Continued

San Gabriel Mountains Continued

San Dimas Experimental Forest, Tanbark

Flats £/

San Dimas Experimental Forest, Bell Canyon a/

San Dimas Experimental Forest, West Fork of

San Dlmae Creek

San Dimas ranger station

San Dimas flood-control dam

San Dimas, 4 mile north of Foothill Boulevard

San Gabriel flood-control dam No. 1 £/

San Gabriel flood-control dam No. 2 &/

San Gabriel River at mouth of canyon a/

San Uab-rlel River, East Fork of

San Gabriel River, East Fork of a/

San Gabriel River, North Fork of^

San Gabriel River at Junction of East and

West Forks

San Gabriel River powerhouse

Sawpit Canyon

Savqplt flood-control dam

Sierra Madre flood-control dam

Sierra Madre, north end of Baldwin Avenue

Sierra Madre, 575 North Heraosa Avenue _a/

Sierra Madre, 621 East Central Avenue

Sleepy Hollow Ranch a/

Sturtevant Camp, upper Santa Anita Canyon

Switzer's eaaj> a/

Tvrjunga flood-control dan

Tujunga Canyon, Southern California Edison

Co.

Latitude

 O I If

34 12 21

34 12

34 10

34 10

34 09 05

34 07 35

34 12 20

34 14 45

34 -09 48

34 14 15

34 16 35

34 15 15

34 13 30

34 09 30

34 11

34 10 31

34 10 30

34 10

34 10 15

34 09 45

34 18 04

34 13 30

34 15 15

34 17 00

34 18 IB

Longitude

0 | tl

117 45 34

117 46

117 47

117 46

117 46 28

117 47 50

117 51 20

117 58 00

117 64 17

117 49 00

117 45 05

117 51 15

117 50 45

117 54 30

117 58

117 59 16

118 02 30

118 03

118 03 30

118 02 30

118 06 42

118 02 15

118 09 15

118 11 45

118 09 30

Altitude 

(feet)

2,700

3,100

2,100

1,500

1,350

1,110

1,251

2,335

800

1,500

2,500

1,790

1,600

850

2,000

1,378

1,400

1,110

1,160

700

3,600

3,375

3,000

2,050

2,60O

February

si

1.26

1.50

1.14

1.21

1.14

1.15

1.49

1190

.27

1.48

.57

*

1.36

1.37

1.03

1.05

.56

1.63

1.54

.40

2.13

2.00

1.20

1.20

1.05

28

3.66

4.80

5.34

2.46

2.19

1.92

3.85

4.53

2.20

3.36

2.93

5.36

3.67

2.80

3.64

3.81

3.54

3.98

3.68

3.07

1.70

6.07

2.69

3.28

2.60

1

3.

.

2.

1.

2.

2.

3.

4.

2.

2.

*

3.

2.

2.

2.

4.

2.

2.

3.

2.

2.

2.

3.

2.
Tujunga

Upper Halnea Canyon a/

Wolfskin Falls, Wolfsklll Canyon 

San Eernardino Mountains

Arrowhead Springs Hotel 

Bear Valley 

Bear Valley Dam 

Beaumont 

Beaumont, north of

Del Rosa ranker station a/

Devil Canyon experimental station a/

Devil Canyon, mouth of

Devore, Cajon Creek

Forest Home, Southern California Edison 

Co.*s intake

Hill Creek powerhouses Hos. 2 

Newark JJeservolr, San Bernardlno 

Panoramic Point, State highway

station

Plunge Creek Divide 

Redlsnds, Crafton Orange Growe

tlon

Redlands, east of

Santa Ana River powerhouse No.

California Edleon Co. 

Santa Ana River powerhouse Ho.

California Edison Co. 

Seven Oaks 

Squirrel Inn 

Yucalpa

San Fernando Valley

Adohr Balry, Ventura Boulevard 

Bell Canyon, Johnson-Woodruff Ranch 

Burbank Airport** 

Burbank

Calabasas

 Included in next measurement.

ron

Lon a/

La Edison

ind 3

30

maintenance

c>s Associa1, Southern

3 , Southern

tench

34 15 00

34 16 18

34 10 30

34 11 15

34 14 15

34 14 45

33 55 45

33 59 00

34 10

34 13 00

34 12 15

34 14 00

34 05 30

34 05 15

34 10 15

34 13 30

34 12 30

34 04

34 03 30

34 08 30

34 06 30

34 10 45

34 13 45

34 02 30

34 09 56

34 12 13

34 11

34 10 55

34 09 26

118 17 15

118 15 11

117 45 00

117 16 00

116 57 00

116 58 30

116 58 45

116 58 15

117 15

117 19 40

117 20 00

117 S4 15

116 56 00

117 OS 30

117 19 00

117 18 10

117 06 30

117 08

117 06 30

117 03 00

117 06 00

116 55 30

117 15 00

117 02 15

118 31 38

118 38 39

118 18

118 18 24

118 38 21

1,850

3,450

2,400

2,000

6,875

6,800

2,580

3,040

2,250

2,700

2,000

2,500

5,000

2,950

1,385

4,000

6,000

1,650

2,000

3,517

2,500

5,000

5,300

2,850

815

930

650

650

950

1.01

1.57

1.58

.30

*

4.96

.63

.45

1.20

1.04

.19

.38

2.23

1.16

.23

*

1.82

*

.30

1.05

1.38

1.42

2.15

.38

.24

.75

.07

1.41

.93

2.12

3.31

6.06

2.05

4.75

3.39

1.28

.95

1.15

3.90

2.13

3.40

2.00

.92

1.93

4.38

4.23

1.69

1.16

1.56

.84

.98

5.10

1.05

1.87

1.26

1.26

1.79

.96

£.07

2.95

.62

1.92

*

1.54

1.76

1.75

1.66

.04

2.40

3.12

2.33

1.31

1.93

1.82

2.61

*

1.20

1.27

1.03

2.10

3.15

1.43

2.52

1.52

1.92

2.43

1.70

**Measured In morning. M Record missin
Table 1.- Daily precipitation, in inches, at standard gages for the period 

(H«aaured in the afternoon exogpfe at not

Station

Santa Ana, San Gabriel, and Los Angeles

River Basins Continued

San Fernando Valley Continued

Chatsworth, Twin Lakes Park fire station a/

Chatsworth, south of Devonshire Street

and east of Vassar Street

Chatsworth patrol station

Chatsworth Reservoir, east end of

Encino Reservoir, 1 mile southwest of

Enclno

Girard, Brant Ranch

Girard, corner Ventura Boulevard and

Topanga Canyon road**

Glendale

Glendale, 448 West Pioneer Drive

Granada pump plant

Griffith Park, north slope of Mount Hollywood

Griffith Park, south slope of Mount Hollywood

Griffith Park Zoo

Headworks power plant, west of north entrance to Griffith Park

Lower San Fernando Reservoir

Miller Ranch, 14163 Van Huys Boulevard

MuLholl and fire station, Franklin Canyon

North Hollywood powerplant

Horth Hollywood

Horth Hollywood, 10834 East Blix Street

Horth Los Angeles, corner Parthenla and

Van Alden Avenues

Olive View Sanatorium

Oneoto Ranch, 13781 Payton Avenue

Ros-coe, 10100 Helen Street

Roecoe, near mouth of La Tuna Canyon**

Latitude

o i n

*

34 16 38

34 15 25

34 15

34 13 36

34 08 56

34 10 16

34 10 06

34 09

34 09 21

34 16 42

34 07 54

34 07 45

34 08 03

34 09 21

34 17 15

34 15 25

34 07 48

34 11 55

34 10

34 09 47

34 13 44

34 19 45

34 16 10

34 15 15

34 14 19

Long! tude

o i n

118 36 12

118 36 20

118 37

118 37 03

118 30 52

118 35 56

118 36 18

118 16

118 15 47

118 30 59

118 17 54

118 17 53

118 17 20

118 18 20

118 29 00

118 26 07

118 24 42

118 23 18

118 24

118 22 17

118 33 02

118 27 00

118 26 00

118 22 00

118 21 28

Altitude 

(feet)

1,249

965

865

865

1,000

892

892

526

526

1,130

1,600

1,400

575

473

1,150

944

1,175

732

630

593

797

1,425

1,005

1,060

1,000

February

27

0.53

1.52

.53

.05

.12

.40

.96

.55

1.35

.48

*

*

1.25

1.44

1.30

.88

1.50

.50

1.40

.32

.12

*

*

1.07

.15

28

1.19

1.58

1.19

1.07

1.65

1.16

1.07

2.78

1.80

1.79

2.14

2.10

1.50

2.09

2.65

1.22

2.43

1.52

1.30

2.26

1.31

2.54

1.55

1.27

1.71

1

2.

*

2.

2.

2.

2.

1.

2.

1.

1.

*

*

4.

2.

2.

1.

2.

1.

1.

3.

1.

1.

2.

1.

1.
San Fernando, Ford Oraig Ranch

San Fernando Lemon Association packing

house** 

San Fernando ranger station, 12605 Osborne

Avenue

Sepulveda Boulevard near Chase Street 

Sepulveda Canyon at Mulholland Drive**

Sylmar, olive-packing plant 

Upper San Fernando Reservoir

Van Nuys, city warshouse, Aetna and Vesper 

. Streets a/

Verdugo Mountains

Brand Estate, Grandview Avenue 

Brand Park a/

Qlendale, 318 East Randolph Street 

Rossmoyne fire area, Glendale a/

Sunset Canyon, Burbank

Veidugo Mountain, Qaksicnt firs read

San Rafael Hills

El Mlrador Ranch, west end of £1 Hlrador

Drive

El Sereno, 4566 BeMlllon Street a/ 

Fllntrldge fire station, Inverness and

Gleneagle Streets

Glendale, 811 North Glendale Avenue 

Highland Park, 6425 Elgin Street

San Rafael Hills, 502 Laksview Avenue 

Sycamore Canyon, 2821 North Chevy Ch*»e Drive 

Tampioo Street a/

San Gabriel Valley

Arcadia

Arcadia pumping plant, north of East Live

Oak Avenue 

Alhambra, corner Second and Main Streets

 Included In next measurement.

34 19 12 

34 16 15

34 15 21

34 13 34

34 07 18

34 18 37

34 18 49

34 10 48

34 10 57 

34 11 19

34 09 55

34 10 50

34 12 '10 

34 12 S3

34 09 56

34 04 54 

34 10 57

34 09 29 

34 07 06

34 07

34 09 57

34 05 30

34 08 20

34 09 32

34 05 40

118 24 59 

118 27 54

118 24 27

118 28 03

118 29 42

118 28 17

118 29 30

118 27 03

118 16 33 

118 16 21

118 15 01

118 14 40

118 17 08 

118 16 17

118 10 46

118 11 08 

118 11 47

118 14 25 

118 10 40

118 12

118 12 23

113 10 30

118 01 48

118 02 02

118 07 43

1,455 

950

955

315

1,400

1,250

1,248

695

815 

1,250

620

1,500

1,650 

2,825

1,025

553 

1,325

653 

680

825

900

600

475

611

485

.77 

.03

.96

.39

.54

*

*

.17

1.28 

1.33

.49

1.15

1.39 

1.42

1.51

1.34 

1.46

1.39 

1.70

1.62

1.39

1.51

1.60

1.22

*

1.72 

1.31

1.44

1.22

2.10

2.32

1.22

1.53

1.60 

2.08

1.85

2.18

2.01 

2.36

2.46

1.69 

2.71

1.82 

2.25

2.14

2.48

1,81

2.73

2.96

4.02

1.76 

2.64

1.58

2.33

4.28

1.43

3.21

2.46

2.14. 

2.54

2.45

2.10

2.44 

2.66

2.17

1.94 

2.35

1.90 

2.01

1.92

2.10

1.88

2.35

2.86

1.88

MHtoaaured In Morning. M Record missin
Table 1.- Dally precipitation, in inches, at standard gages for the per 

_________________________(Measured in the afternoon except as

iod F

note

Station

Santa Ana. San Gabriel, and Los Angeles

River Basins Continued

San Gabriel Valley Continued

Azusa, rear of city hall

Azuaa, Foothill Ranch, 2 miles west of

Cltrua Avenue

Azuaa, Bonita Street, west of Cerrltos

Avenue a/

Azuaa, 326 Foothill Boulevard

Baldwin Park experiment station, Scott Place

Baldwin Park, 384 North Main Street

California Institute of Technology &/

Chapman Wells, Sierra Madre Avenue

Charter Oaks, Covina Boulevard

Covina, City Water Department, 125 East

College Street

Covina, 161 Uavllla Place**

Covina, Puente Street, east of high school

Covina, Gamer on Avenue

Diamond Bar Ranch, Spadra office

El Monte, fire station

Olendora, 234 North Michigan Avenue

Qlendor* Irrigation Co., Azusa plant

Ql«ndora, Pennsylvania and Sierra Medre

Avenues

Olendora Irrigation Co., Sierra Madro

Avenue

Qlendora, 460 East Bennett Avenue

Eowell Ranch, 1 mile west of Walnut post

office

Hurst Ranch, Orange and Merced Avenues,

near Covina

Lamanda Park

La Verne, at Pacific Electric Railway

station

La Verne, 2168 Third Street

Latitude

o t n

34 08 04

34 08 00

34 06 24

34 08 02

34 05 38

34 05 17

34 08 16

34 08 48

34 06 00

34 05 15

34 04 55

34 04 57

34 03 39

34 02 15

34 04 27

34 08 22

34 09 00

34 08 49

34 08 51

34 08 23

34 00 04

34 03 51

34 08 56

34 05 47

34 06 01

Longitude

o t n

117 54 17

117 53 37

117 53 58

117 54 14

117 57 39

117 57 35

118 07 38

118 04 05

117 50 02

117 53 18

117 53 17

117 52 28

117 52 38

117 48 43

118 02 08

117 51 54

117 55 00

117 52 04

117 52 53

117 51 33

117 52 21

117 57 00

118 05 42

117 46 16

117 46 07

Altitude 

(feet)

607

615

545

602

387t

378

763

635

805

583

527

575

630

675

301

782

675

825

865

822

475

358

742

1,036

1,054

February

27

1.33

1.42

1.31

1.40

*

1.60

1.62

1.60

1.50

1.27

1.98

1.36

' .98

*

*

1.28

1.25

1.35

1.37

.98

*

1.64

*

1.00

1.00

28

2.25

2.40

1.75

2.22

2.42

1.60

2.72

2.79

1.65

1.51

.83

1.48

1.33

1.85

2.65

2.39

2.34

2.56

2.40

2.45

2.28

1.59

3.72

1.75

1.52

1

2.3

2.4

2.0

2.3

2.6

1.7

2.2

2.3

1.9

1.9

1.8

1.8

1.6

1.5

2.0

2.5

2.4

2.7

2.6

2.6

1.8

1.8

3.9

1.8

1.7
Marks pasture, Puente Hills 

Monrovia, on roof of city hall 

Monrovia, 432 North Primrose Street 

Newark, Merced Hills, Southern California

Edison Co. £/ 

North Whittier, Cole Ranch, Seventh Avenue

North Whittler Heights, 1058 Los Robles

Avenue 

North Whittier Heights

Pasadena

Panadena, Central fire station a/

Pasadena, Ohio and Euclid Streets *J

Pasadena, Sunset Reservoir */ 

Pasadena, Washington Street and Palm

Potrero Heights, 3623 Delta Street 

Puddingstone Dam, at caretaker's house 

Puente, Southern California Edison Co. 

substation

Rowland Ranch at ran oh house, near Puente 

San Dimas, Juanita Avenue east of Walnut

Avenue

San Dimas, 167 North San Dimas Avenue 

San Dimas, 114 East First Street 

San Dimas Water Co. pumping plant, Foothill

Boulevard and Artesia Avenue

San Gabriel, 424 North Milton Avenue 

San Gabriel, 309 East Live Oak Avenue 

Sierra Hadre, 415 East Live Oak Street 

South Pasadena, city hall 

State Narootio Hospital near Spadra

Walnut Fruit Growers Association, 0.5 mile

southeast of Walnut 

West Arcadia, 2307 Naomi Drive 

West Azusa

Whittier Narrows (Paso de Bartolo)

34 01 55

34 08 57

34 09 32

34 02 45

34 00 23

34 00 20

34 01 15

34 08 55

34 08 50

34 07 43

34 09 43

34 10 08

34 02 37

34 05 30

34 00 34

33 59 37

34 06 38

34 06 31

34 06 28

34 07 23

34 06 32

34 06, 07

34 09 29

34 06 58

34 02 51

34 00 13

34 07 25

34 06 51

34 00 54

118 04 57

118 00 02

118 00 25

118 07 43

117 59 46

117 59 22

117 58 38

118 08 36

118 08 47

118 08 34

118 09 17

118 08 12

118 05 10

117 48 24

117 55 46

117 56 30

117 47 59

117 48 25

117 48 22

117 47 36

118 06 19

118 05 45

118 02 36

118 09 05

117 50 50

117 51 11

118 03 40

117 54 58

118 04 25

600

600

675

375

600

500

312

864

862

755

930

1,010

320

1,030

374

466

1,000

963

960

1,064

487

433

665

660

770

533

490

505

195

1.65

.97

.40

1.65

1.62

1.75

2.44

1.72

*

*

1.65

1.16

.32

1.09

1.53

.25

1.10

1.16

1.12

1.00

*

1.65

1.43

1.60

.17

*

1.32

1.43

1.16

1.35

2.65

2.60

1,67

1.23

1.22

*

2.53

3.53

3.50

2.61

3.06

1.61

1.64

.91

2.00

1.84

1.65

1.67

1.74

3.07

2.10

3.60

2.10

1.74

2.29

2.23

1.84

1.13

2.25

2.20

3.21

1.63

2.00

1.90

1.97

2.18

2.70

2.68

2.27

2.60

2.98

1.68

1.64

2.05

2.01

1.91

1.90

2.02

2.60

1.83

2.60

2.15

2.02

1.89

2.38

2.21

1.73

 Included In next measurement. Measured in morning. 
Table 1.- Daily precipitation, in inches, at standard gages for the period Feb

(Measured in the afternoon except as noted)

Station

Santa Ana, San Gabriel, and Los Angeles

River Basins Continued

Chino Valley

Alta Loma Citrus Association, near Upland

Braundale Acres, east of Ontario

1

Chino Ranch, American Beet Sugar Co.**

Chino plant, American Beet Sugar Co.**

Chino, Big W Ranch

Cbino, Southern California Edison Co., substation

Claremont, fire station. Second Street

Claremont, Pomona College Observatory */

Cucamonga, 1 mile east of

Etiwanda &/

Ouasti, Guasti Wine Co.

Highland Avenue

Highland Avenue, 3 miles northwest of

Cucamonga

Mission Winery, near Cucamonga

Ontario, Chaffey Union High School

Ontario, West Ontario Citrus Association

Ontario, Southern Pacific Co.

Pomona, 987 North Weber Street**

Pomona, 2211 South Tower Avenue

Pomona, Southern Pacific Co.

Upland, 1544 North Bens on Avenue

Upload, West Ninth Street and North San

Antonio Avenue

Upland, West Twenty second Street near

Mountain View Avenue

Upland, north of

Upland, West Tenth Street near Mountain

Avenue

Latitude

o i n

,

34 07 30

34 02 45

33 59 15

34 00 30

34 01 15

33 59 50

34 05 47

34 05 52

34 06 15

34 OS 15

34 04 00

34 09

34 OS 45

34 06 25

34 04 45

34 03 45

34 03 30

34 04 03

54 25 57

34 03 34

34 07 00

34 05 45

34 09

34 OS

34 06 00

Longitude

o t n

117 35 30

117 37 00

117 40 15

117 42 00

117 41 00

117 40 45

117 42 59

117 42 34

117 34 20

117 31 00

117 35 15

117 35

117 36 00

117 34 35

117 39 00

117 41 00

117 39 00

117 46 23

117 44 26

117 45 04

117 40 45

117 39 30

117 39

117 38

117 40 45

Altitude 

(feet)

1,325

900

714

710

750

670

1,165

1,190

1,150

1,450

975

1,575

1,650

1,175

1,150

991

990

838

778

362

1,550

1,215

1,740

1,275

February

27

*

0.65

*

.42

1.05

.95

.82

.79

*

*

*

.10

.39

.63

*

*

1.37

.12

1.18

.10

.73

*

.10

*

.63

23

2.33

.77

1.26

.95

.80

.48

1.24

1.25

*

1.73

1.08

1.56

2.49

.92

1.30

1.79

1.76

1.45

.75

1.55

1.39

2.17

1.42

1.45

*

1

1.96

1.43

1.50

1.74

1.49

1.44

1.66

1.63

3.02

2.45

1.85

2.62

2.11

1.53

1.90

1.69

3.02

2.11

1.65

1.87

1.75

1.96

1.9S

2.72

2.79
Upper Santa Ana Valley

Blooaington, Citizens Land & Water Co. 

Colton, Police Department 

Colton, Southern Pacific Co.

Crown Jewel Groves,

East Highlands

mile west of Redlands

Do.

Fontana

Fontana, Fontana Farms Co. 

Gage canal headgate** 

Highlands, 1 mile northeast of

Lytle Creek, Base Line Street**

Redlands «*

Redlands

Rialto

San Bernardino, Second and D Streets 

San Bernardino

Jurupa Basin

Citrus experiment station, University of

California a/ 

Mira Loma Ranoh

Riverside

Riverside, San Jacinto Land Co.

San Jacinto River Basin

Backus Ranch

Decker Ranch**

Elsinore**

51sinor«, 1& miles east of

Elsinore, west end of Lake Elsinore

Idlewild

Lake Hemet Dam

Lawrence adit

March Field, U. S. Araty Air Corps

 Included In next measurement 

54 04

34 04 00

34 04 00

34 04 30

34 07

34 07 15

34 06 30

34 06

34 05 00

34 08 00

34 07 30

34 03 00

34 03 30

34 06 30

34 06 00

51 OS 00

33 58 30

34 01 30

33 58

33 53 30

34 36

33 49 '

33 40

33 41 00

33 40 45

33 45

33 45

33 39 45

33 53

33 53 45

117 24

117 19 30

117 19 30

117 12 45

117 10

117 10 00

117 25 30

117 26

117 15 30

117 11 45

117 21 00

117 10 30

117 11 00

117 22 00

117 17 15

117 16 30

117 20 00

117 31 10

117 26

117 26 45

118 12

116 45

117 20

117 17 50

117 24 00

116 57

116 43

116 42 45

116 53

117 15 30

1,100

975

975

1,200

1,400

1,400

1,325

1,175

1,050

1,450

1,172

1,500

1,360

1,175

1,048

1,172

1,075

825

895

975

2,620

5,550

1,272

1,400

1,272

1,700

5,300

5,000

2,840

1,500

»

1.35

.13

*

1.30

1.30

.68

*

.16

2.22

.30

.54

1.10

.65

.41

1.36

.21

*

.12

1.29

*

.50

2.18

1.00

1.24.

.65

1.36

*

1.51

.66

1.32

.69

1.83

1.76

.88

.88

1.11

1.36

1.62

1.32

1.60

.91

.44

.77

1.67

1.10

.52

1.00

.93

.91

.86

1.74

.32

1.43

1.26

.22

#

.68

.98

.54

#

1.17

1.33

1.03

1.20

1.20

1.30

1.44

1.00

1.08

1.72

1.07

1.05

1.54

1.38

1.34

1.10

1.46

.96

.69

.65

3.00

1.02

1.07

1.80

1.65

2.07

1.55

.82

.84

**Mesaured In morning.
Table 1.- Daily precipitation, in inches, at standard gage* for the period Fe

(Measured in the afternoon sxeept aa noted

Station

Santa Ana. San Gabriel, and Loa Angeles

Elver Basins Continued

San Jacinto River Basin Continued

flaynard Ranch

Perrls*»

Portero shaft

Poppet Flats 

San Jaolnto

Sims Ranch

Vista Grande Ranch

Temescal Creek Basin

Cajalco Ho. 1

Cajalco Reservoir 

Corona. 

Corona, Jamison Co.

Corona, Temescal Water Co.

Corona, Foothill Lemon Co. 

Corona, Foothill Lemon Co. 

Corona, Foothill Lemon Co. 

Corona, Foothill Lemon Co. 

Orange Heights Water Co., near Horco 

Temescal, Temesoal Water Co.

Santiago Creek Basin

Limestone Ranoh, Irvlne Ranch Co. 

Peters Canyon Dam, Irvine Ranch Co.

Santiago Canyon 

Santiago Bam, Irvine Ranch Co.

Silverado Canyon at head 

Silverado Canyon, Holtz Ranch

Latitude

33 54

53 45

33 50

33 51 

35 47 00

33 48

33 49

33 50

33 50 30 

33 51 30 

33 51 30

33 52 30

33 51 45 

33 CO 45 

33 49 50 

33 50 45 

33 56 30 

33 46

33 46 

53 47 45

33 44 

33 47 00

33 45 

33 44 45

Longitude

0 | R

117 02

117 11

116 56

115 51 

116 57 4B

116 52

116 47

117 27

117 21 30 

117 54 15 

117 33 00

117 34 00

117 35 50 

117 34 4B 

117 34 50 

117 32 15 

117 33 30 

117 29

117 43 

117 46 00

117 39 45 

117 43 16

117 34 

117 38

Altitude 

(feet)

1,960

1,466

2,525

3,540 

1,550

2,100

5,000

1,290

1,300 

850 

875

700

850 

1,050 

1,350 

850 

800 

1,075

1,000 

550

1,050 

1,025

2,000 

1,500

February

27

*

1.00

1.03

« 

.85

.98

2.45

*

* 

.15 

1.43

.39

.50 

.50 

.60 

.50 

.53 

.81

.31 

.31

.32

1.30 

.20

28

2.60

.55

.97

1.80 

.32

.56

2.21

1.13

.98 

1.35 

1.53

.98

1.19 

1.42 

1.57 

1.10 

.43 

1.45

1.27 

1.30

1.40

1.47

2.70 

1.19

1

*

1.15

.91

* 

1.28

1.55

.68

.70

.86 

1.35 

1.28

1.35

1.42 

1.45 

1.58 

1.24 

1.01 

2.06

1.81 

1.23

1.86 

1.75

2.08 

2.68
Coastal plains

Allao, Irvlne Ranch Co.

American Beat Sugar Co., near Westminster

Anaheim, city water works 

Anaheim, Anaheim Union Water Go.

Anaheim Associate Laboratories

Artesla, 1804 Pioneer Street

Avalon

Bell, fire dBpartment, 6320 Pine Street

Bellflower, 900 East Park Avenue, at

Somerset Avenue 

Bel-Air, administration building a/

Blxby Ranch, Walnut Canyon

Beverly Hills, city hall a/ 

Buena Park, Kelson Hardware Co.

Carbon Canyon

Carroll Ranch, 3 miles west of Anaheim

Cemetery near El Toro

Clark Memorial Library, 2205 West Adams St. 

Compton, 401 South Polnsettla Avenue 

County Farm, 741 Old River School Road 

Culver City, corner Jefferson and Duquesne 

Streets

Curson Canyon

Downey, fire station, Downey and Firestone

Boulevards

Downey, 241 North Downey Avenue** 

Downey, 751 Florence Avenue

Diamond Bar Ranch, Brea Canyon road

Domlnguez Hills, near reservoir 

El Segundo, Standard Oil refinery 

Fuller-ton, airport***

Fuller-ton

Fuller-ton, evaporation station a/

33 43

33 45 00

33 49 45

33 49 45

33 50

33 51 35

33 18

33 58 44

3* 52

34 05 11

33 50

34 04 27

33 51 45

33 58 00

33 50

33 39 00

34 02 00

33 53 36

33 56 17

34 01 00

34 06 51

33 56 33

33 56 30

33 57 30

33 58 00

33 51 37

33 54 55

33 52 15

33 52

33 52

117 50

118 00 30

117 54 45

117 55 00

117 56

118 04 52

118 14

118 11 25

118 08

118 26 45

117 46

118 23 57

117 59 45

117 45 45

117 58

117 40 45

118 18 50

118 12 36

118 09 22

118 23 17

118 21 13

118 08 10

118 08 00

118 08 15

117 50 40

118 14 01

118 25 10

117 58 30

117 55

117 58

62

25

150

150

125

49

30

145

68

540

500

255

90

1,150

105

700

203;

67

104

65

1,125

117

119

128

710

195

135

92

_

90

.30

.32

*

*

*

*

.49

1.65

1.65

1.58

*

1.42

1.46

.15

.12

.28

1.25

1.63

1.58

.17

1.48

1.77

1.62

1.65

.98

1.71

1.11

1.09

1.47

*

1.00

1.43

1.57

1.63

1.60

1.72

1.62

1.31

.51

2.02

2.15

2.24

1.49

1.95

1.50

.91

1.74

.48

.46

1.56

2.05

.67

.62

.51

1.44

.44

.65

1.74

.85

*

.96

1.55

1.93

1.85

1.65

1.55

1.22

1.85

1.47

2.00

1.95

1.79

2.20

1.76

1.46

1.61

1.64

1.36

.54

2.25

1.94

1.52

1.65

1.47

1.75

1.43

1.23

.53

1.39

3.22

»Included In next measurement. 

 Measured In the morning.

***Heasured at midnight. 

H Record missing.
Table 1.- Dally precipitation. In Indies, at standard period F

Station

Santa Ana, San Gabriel, and Los Angeles

River Basiu^ CJontlnued

Coastal plains Continued

Fullerton, water department

Fullerton, water department

Garden Grove

Garden Grove, Alien Brothers Ranch

Garden Grove, Garden Grove Lumber Co.

Oardena, Vermont and Rosecrans Boulevards

General Petroleum Corporation, 2 miles

northwest of Tor ranee

Griffith Park Nursery, North Commonwealth

Avenue a/

Griffith Park tunnel

Hamilton Bowl, near Signal Hill

Hanpook Park, 5801 Wilshlre Boulevard a/

Harkel road camp, Irvine Ranch

Hewea Park, He was Ranch

Hole pumping station, Union Oil Co., near

Fullerton

Holly Sugar Co., near Santa Ana

Hollywood, 6225 Santa Monica Boulevard

Hollywood, Hollywood Dam

Huntington Beaoh, Sj miles north of

Huntington Beach

Huntington Beach, Union Oil pumping station

Huntington Beach, evaporation station

Huntington Park, city yard, Slauson and

Miles Streets

Hyaes, S47 South Paramount Boulevard

Inglewood, high ichool

Irvine warehouse, Irvine Ranch Co. 

Latitude

e i n

33 53 00

33 50 45

33 46 15

33 47 00

33 46

33 54 07

33 51 11

34 07 12

34 07 24

33 47 27

34 03 48

33 40 30

33 46 45

33 53 45

33 42 30

34 05 28

34 07 04

33 43

33 40 00

33 41 15

33 43 15

33 59 02

33 52 58

33 57 38

33 40 15

Longitude

o i n

117 55 15

117 55 30

117 56 30

117 56 30

117 56

118 17 29

118 20 26

118 17 11

118 18 11

118 10 07

118 21 19

117 47 45

117 48 30

117 54 30

117 51 15

118 19 30

118 19 55

118 00

118 00 15

118 00 15

118 02 00

118 13 06

118 09 36

118 21 20

117 45 15

Altitude 

(feet)

155

200

95

90

64

75

750

1,100

25

177

100

640

_

55

305

750

25

35

65

15

175

72

117

200

February

27

1.13

1.47

*

.49

.38

1.60

1.28

1.22

*

1.10

1.26

.12

.16

.92

1.32

*

2.39

*

1.44

.11

*

1.60

1.65

.81

.32

28

0.85

.35

1.20

1.42

1.34

.45

.46

1.80

2.03

.36

1.75

1.18

1.56

1.35

.94

2.98

2.10

*

.55

1.97

1.35

1.23

.42

. 1.55

.97

1

1.2

1.3

1.4

1.8

1.3

1.7

1.3

1.6

1.8

1.1

1.6

1.1

.5

1.9

1.3

1.9

2.9

2.8

1.1

1.3

*

1.6

1.4

1.5

1.5
Johnson Ranch, Irvine Ranch Co.

Laguna Bell a/

La Habra, Zinn Laboratory

La Habra Citrus Association

LR Habra project, Goodell-Proud Ranch

La Habra project, Harts Ranch

La Habra project, Murphy Cojote HanchOageNo. 1

La Habra project, Murphy Coyote HanchOage No. 2

La Habra project, Wardman Ranch

La Habra project, Weisel Ranch

La Mlrada, Center Street

Lambert Ranch, Irvine Ranch Co. 

La Vida Mineral Springs

Long Beach, city hall**

Long Beach, 22 Pacific 'Avenue**

Long Beach

Long Beach*** 

Long Beach** 

Long Beach** 

Long Beach**

Long Beach**

Long Beach**

Los Angeles, Second and Hill Streets

Los Angeles, Eighth and Figueroa Building

Los Angeles, 4213 West Second Street

Los Angeles, Los Angeles Junior College** 

Los Angeles, West Eightieth Street 

Los Angeles, municipal airport 

Los Angeles, Silver Lake Reservoir 

Los Angeles, Ninety-sixth Street and 

Central Avenue a/

Mandevllle Canyon, administration building 

Moore, Mrs. A. H.

Montana Ranch, 3 miles southwest of Artesia 

Montebello, 117 West Washington Avenue 

Mount St. Mary's College

33 39

33 58 38

33 55

33 55 45

33 55 57

33 57 10

33 55 46

33 55 39

33 56 10

33 57 08

33 53 15

33 41 45

33 55 45

33 46 12

30 46 05

33 46 00

33 46

33 45 45

33 49 30

33 51 45

33 46 45

33 47 15

34 03 38

34 02 55

34.04 16

34 05 21

33 58 00

33 56

34 06 08

33 57 00

34 03 57

33 43 00

33 50 35

34 00 44

34 OS 06

117 43

118 08 46

117 56

117 57 00

117 56 48

117 57 26

117 57 45

117 58 15

117 54 49

117 55 30

118 00 58

117 42 30

117 48 00

118 11 35

118 11 35

118 11 16

118 12

118 08 30

118 10 15

118 10 45

118 08 30

118 11 46

118 14 48

118 15 45

118 18 19

118 17 34

118 18 29

118 23

118 15 54

118 15 25

118 29 35

118 00 25

118 07 09

118 05 58

118 28 53

320

140

300

300

300

520

275

300

480

540

86

400

850

30

30

25

70

-

-

_

13

385

260

238

315

97

455

121

470

25

47

205

1,015

.32

1.72

*

*

*

1.95

1.64

1.87

1.52

1.39

.18

.30

*

.68

1.05

1.10

.02

.65

.77

.52

.62

1.18

*

1.30

1.41

1.30

1.75

.30

2.67

1.68

.72

.90

.24

1.30

1.70

1.06

.64

1.82

1.82

2.50

2.13

*

*

1.23

1.02

1.27

1.12

1.99

.96

.52

.36

1.38

.88

1.03

.69

.84

1.30

2.37

1.57

1.73

1.81

2.52

1.15

2.43

1.18

2.30

1.25

1.44

.90

2.18

1.

1.

1.

2.

1.

2.

1.

1.

1.

1.

1.

1.

2.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

3.

1.

3.

2.

1.

1.

1.

2.

*Included in next measurement. *»Measured in the morning. ***Measured at mid
Table 1.- Daily precipitation, in inches, at standard gages for the period F

(Measured in the afternoon except as note

Station

Santa AOA.San a«bri*l, and Los Angeles

HIVtr JBUffijBlf uontl nued

Coastal plains Continued

Murcly, J. A., ranch, south of Westminster

Navanjal pumping station, 2 miles west of

Brea

Newport Harbor, near entrance

Newport Beach (Balboa)

Uorwalk, 1 mile southeast of

Old Ranch, Irvine Ranch Co. 

Orange, i Bile north of

Orange

Orange, i mile south of

Paloa Verde* , Golf Club

Pal OB Verdes Satates, 75 Malaga Cove Plaza

Placentia, Plaeantia Mutual Orange As-

 ociation

Placentia, it nilea west ef

Placentia, 9f milea eaat of

Point Vicente Lighthoute

Puente Hilla (La Habra Heights)

Redondo, city hall

Rivera Pico

Salt work* li milea north of Newport

Santa Ana, Hill & Son, hardware

Santa Ana

Santa Ana, Orange County Flood Control

Dittrict office a/

San Joaquin Fruit Co.

Santa Monica

Santa Monica, 1245 Fourth Street

San Pedro Hilla, at weat end

San Pedro

Seal Beaeh, powerhouas

Lati tude

o i n

33 43 30

33 55 40

33 36 15

33 36

33 53 50

33 39 45

33 48 30

33 47

53 46 30

33 47 47

33 48 00

33 52 00

33 52 15

33 52

33 44 30

33 57 15

33 50 28

33 59 33

33 37 30

33 45

33 46

33 45 00

33 42 30

34 02

34 01 06

33 46 30

33 43

33 44 30

Longitude

0 | It

118 00 45

117 51 25

117 52 45

117 54

118 03 58

117 53 50

117 49 45

117 51

117 50 30

118 22 12

118 23 20

117 52 30

117 54 00

117 46

118 24 38

117 54 20

118 23 22

118 04 54

117 53 00

117 52

117 51

117 52

117 45 00

118 28

118 29 50

118 22 53

118 17

118 06 45

Altitude 

(feet)

25

575

50

15

83

50

200

200

205

450

300

205

195

350

125

725

50

173

40

133

133

130

197

140

100

1,235

90

25

February

27

0.10

.55

.30

.40

1.36

.30

.40

.43

.46

*

1.80

1.20

.86

1.20

.78

1.39

*

1.14

.34

*

1.38

.37

.40

.80

.30

1.92

.09

1.11

28

1.40

1.25

1.12

.95

.52

1.12

1.45

1.46

1.40

2.10

.63

.87

1.08

.57

.39

1.02

2.02

.77

1.30

1.60

.84

1.31

1.30

1.70

2.63

.79

.85

1.77

1

1.4

1.5

1.1

1.3

1.5

1.1

1.9

1.6

1.6

1.5

1.1

1.9

2.5

1.5

1.2

1.9

1.2

1.7

.9

1.3

1,0

1.3

1.3

1.5

1.5

1.4

1.5

.9
Shady Ranch, Irvlne Ranch Co. 

Signal Hill, city hall a/

National Military Home

Southern California Edison Co., 1$ miles

south of Anaheim 

Stanton 

Stewarts pumping station, Union Oil Co.

Stone Canyon Dam

Sunny Hills Ranch, laboratory

Sunny Hills Ranch, Lemon Mesa 

Sunny Hills Ranch, Red Tank 

Sunny Hills Ranch, Santa Fe 

Sunny Hills Ranch, Vlejo

Talbert Avenue

Telegraph Road, 0.2 mile west of San Gabriel River

Tor ranee, Southern California Edison Co. 

substation, 190th Street and Western 

Avenue

Tuatln

Tustin, Union High School

Tuatln, near home ranch of Irvlne Ranch Co. 

Union Oil Co., near Brea

University of California at Los Angeles,

near Westwood

Upper Franklin Canyon Reservoir 

Venice, city hall

Villa Park Orchard Association

Watts, 103d Street 

Western Avenue Reservoir 

West Los Angeles, city hall 

Whlttier, city hall

Whittier News

Whit tier, east of 

Whittier, Lefflngwell Ranch 

Whittier. Laurel Avenue 

Wilmlngton, 1251 Banning Boulevard 

Yorba Linda

*Included In next measurement.

33 37 30

33 47 49

34 03 25

33 48

33 49

33 55 55

34 06 25

33 53 35

33 53 10

33 54 30

33 52 30

33 54 10

33 42

33 57 10

33 51 32

33 43

33 44 00

33 43

33 54

34 04

34 07 11

33 59 18

33 49 00

33 56 37

33 56 54

34 02 44

33 58 53

33 58 50

33 57

33 56 25

33 57 33

33 47 20

33 53

117 48 00

118 10 03

118 27 17

117 54

118 00

117 54 50

118 27 13

117 55 35

117 57 10

117 56 20

117 57 25

117 55 35

' 117 58

118 05 49

118 18 33

117 48

117 49 30

117 47

117 52

118 26

118 24 38

118 27 33

117 49 30

118 13 45

118 18 35

118 26 57

1^8 02 13

118 02 10

118 01

117 59 35

118 01 49

118 15 32

117 49

300

115

335

135

55

335

725

292

225

400

112

295

25

141

' 57

125

120

130

_

180

867

17

290

110

235

232

365

350

 215

253

215

40

406

.48

1.35

1.35

.92

.95

.11

2.78

.25

*

*

*

*

.32

1.50

1.32

.32

*

.30

.70

.27

1.35

«

«

*

1.30

*

1.28

.61

1.28

*

1.43

1.39

.70

1.20

.50

2.12

.82

1.91

1.45

3.31

1.75

1.94

2.05

1.80

2.00

1.30

.55

.45

.97

1.50

1.15

.92

2.49

1.99

2.96

1.93

2.35

2.50

3.50

.67

1.15

.67

1.95

.61

1.49

.84

1.7

1.

1.

2.

2.0

1.7

3.

1.6

1.5

1.

1.

1.8

1.1

1.5

1.

1.

1.

1.1

1.7

2.6

2.0

1.

1.9

1.

.

1.7

1.6

1.7

1.

1.

1.

.

1.7

a See table 
Table 1.- Dally precipitation. In Inches, at standard gages for the period 

(Measured In Bie afternoon except as not

Station

Topanga, Mallbu, and Calleguas Creek Basins

Aggen Ranch, near Somls**

Bel Air Bay Club, Coast Highway

Broome Ranch, near Point Mugu

Camarlllo, American Crystal Sugar Co. Ranch**

Cone jo Ranch, near Newbury Park**

Crags Country Club, southwest of Calabassas

Dume Canyon

Escondido patrol station, Escondldo Canyon

Garrapata Canyon, 0.5 miles northeast of

Topanga Canyon road

Hueneme, lighthouse**

Eerr Ranch, near Pair view

Lake Sherwood

Lechuza, patrol station on Decker road a./

Las Posas project, Agourre Ranch

Las Posas project, Culbert Ranch

Las Fosas project, Dletrlch Ranch

Las Posas project, Goodyeaf Ranch

Las Posas project, Honda Ranch

Las Fosas project, Jones Ranch

Laa Posas project, Le Fever Ranch

Las Posas project, Mahan Ranch

Las Posas project, Mullinlx Ranch

Las Posas project, Pelterlno Farm

Las Posas project, Puerta Zuela Ranch

Las Posas project, Stockton Ranch

Las Posas project, Thille Ranch

Las Posas project, Waters Ranch

Mason estate, East Fork of Arroyo Sequls

North Simi, Union Oil Co. lease**

Oznard

Latitude

o i n

34 16 17

34 02 28

34 09 15

34 12 15

34 10 30

34 05 53

34 04 58

34 03 02

34 07 03

34 08 40

34 18 50

34. 08 52

34 04 50

34 16 04

34 15 47

34 16 17

34 16 23

34 16 50

34 19 53 

34 16 17

34 17 36

34 16 51

34 18 26

34 18 05

34 17 42

34 15 48

34 17 15

34 05 13

34 17 50

34 11 30

Longitude

e f n

119 02 04

118 32 45

119 02 20

119 04 15

118 50 30

118 43 45

118 49 38

118 46 25

118 35 02

119 12 37

118 53 30

118 50 10

118 52 38

118 58 34

119 02 20

119 03 51

119 01 20

119 02 22

118 57 34

119 02 59

118 58 33

119 OO 40

119 02 03

118 58 00

119 03 06

119 03 36

119 04 53

118 53 27

118 47 00

119 10 25

Altitude 

(feet)

375

95

75

140

860

575

1,500

1,025

990

40

870

1,030

1,530

382

367

475

425

508

1,150

450

621

456

825

900

620

309

900

1,155

1,000

51

February

27

*

1.02

*

.03

*

*

.75

.49

1.20

*

*

1.02

.60

*

*

.12

12

.42

*

.70

0.64

1.35

.65

.85

.84

2.75

2.90

2.00

2.70

.65

1.03

.78

2.42

.90

-

.82

.84

.85

.68

1.12

2.84

.68

.91

3.14

.30

.69

.78

2.85

1.89

.84

1.89

1

2

1

1

2

2

4

1

2

1

1

2

2

2

1

1

1

2

2

2

2

2

2

2

3

2

1

S
Santa Ynez Canyon

Santa Rosa Valley, Janns Investment Co.

Seminole Hot Springs, La Sierra Canyon 

Somie, Snyder Ranch

Tapo Mutual Water Co., near Santa Susans

Topanga Canyon, 4 miles south of Topanga

Bridge a/

Topanga Summit, on Topanga Canyon road 

West Saddle above Crater camp 

Wolf Ranch near Santa Susana

Santa Clara and Ventura River Basins

Acton, Just east of summit, Mint Canyon road 

Acton, Modie Ranch

Acton, north branch of Escondido Canyon a/ 

Aliso Canyon south of Acton 

Borgstrom Ranch, east of Ventura

Bouquet Canyon, Artesian Springs a/ 

Bouquet Canyon, Cherry Summit a/ 

Bouquet Canyon, Bouquet Canyon road near

Lincoln Crest a/

Pouquet Canyon, at reservoir yard a/ 

Bouquet Canyon, Spunky Summit a/

Bouquet Canyon, East Spunky Summit a/ 

Camulas Ranch, near Piru**

Casitas Ranch, near Casitas** 

Del Mar Ranch, west of Saticoy** 

Dry Canyon Reservoir

Pillmore

German, on Ridge Route

Hananond Canyon, Ran oho Canada Larga

Kingston Reservoir, near Ventura 

Krotona Hill, near OJal**

Lathrop Ranch, near Wheeler Springs** 

Leavens and Goodnougb, Ranch, near Fillmore** 

Limoneira Ranch packing house, near Santa 

Paula**

*Included in next measurement.

34 04 09

34 14 10

34 06 25

34 15 49

34 17 45

34 05 08

34 08 23

34 04 28

34 16 45

34 31 15

34 25 20

34 29 51

34 27 40

34 16 45

34 34 20

34 35 20

34 35 00

34 35 10

34 36

34 36 30

34 24 10

34 22 15

34 16 45

34 38 55

34 24 15

34 48 00

34 22 50

34 20 30

34 26 05

34 33 15

34 23 30

34 20 00

118 33 34

118 55 50

118 47 38

118 59 57

118 43 15

118 35 58

118 36 00

118 41 19

118 43 35

118 13 30

118 11 52

118 15 56

118 09 25

119 15 00

118 22 05

118 23 40

118 18 20

118 21 40

118 23

118 21 45

118 45 20

119 20 15

119 11 37

118 31 40

118 54 50

118 51 00

119 13 50

119 17 45

119 16 20

119 12 30

118 50 20

119 07 50

500

300

875

300

1,080

747

1,520

890

980

3,250

3,100

3,075

2,900

200\

3,650

2,975

3,600

3,000

3,500

3,725

730

400

300

1,507

530

3,830

800

210

830

3,210

550

335

*

*

.63

*

*

1.27

*

.81

.34

.50

»

.59

1.17

*

.48

.45

.70

.42

.54

.57

.36

»

.29

.05

*

*

»

.05

*

*

.24

.20

4.00

.73

1.82

.88

Z. 48

3.03

2.70

2.79

.70

.26

1.93

.26

.27

1.09

1.06

.89

.95

1.99

.79

.90

.97

1.10

1.11

.67

1.02

1.15

1.00

1.14

.74

1.14

1.10

1.10

*

1.5

2.5

1.9

*

3.0

1.9

2.6

1.1

.7

1.3

.8

.9

2.1

1.2

1.2

1.0

.1

1.1

1.0

1.4

2.7

1.8

1.2

1.9

.8

2.5

2.5

2.4

2.2

1.4

2.1

**Meaeured in the morning. 
Table 1.- Daily precipitation, in inches, at standard gages for the period 

(Measured in the afternoon except as note

Station

Santa Clara and Ventura River Basins Con.

Natilija Canyon, Sheldon Ranch**

Mint Canyon at Oak Oarage 

Moorpark at S. P. Milling Co.

Munz Ranch, between Elizabeth and Hughes

Lakes

Swnall,* mile north of

Newhall, ranger station

Newhall, at Southern Pacific Railroad station

Oliver Young Ranch

OJal Valley

OJai Valley

Pine Canyon patrol station, between Hughes

and Elizabeth Lakes

Pine Tree Ranch, near Santa Paula**

Piru, Piru 'Citrue Association

Piru, Newhall Ranch fir chard

Placerita Canyon at Dulin Ranch

Plush Ranch, 5 miles west of Griffin

Radium Hot Springs, Elizabeth Lake Canyon

Rancho Ma till Ja, near OJai**

Rancho Sespe, near Fillmore**

Ridge Route, 11 miles south of Qorman

Rouff Raich," on Bouquet Canyon road

San Francisquito Canyon, powerhouse 1

San Francisquito Canyon, powerhouse 2

Sandbergs, on old Ridge Route

Sand Canyon

Santa Ana Valley, near Oakview**

Santa Paula, Blanchard Investment Co.

Santa Paula Canyon, Femdale Ranch**

Lati tude

o t n

34 28 45

34 30 46 

34 17 00

 34 40 00

34 23 07

34 22 13

34 22 47

_34 22 55

34 27 15

34 27 00

34 40 20

34 22 20

34 24 35

34 24 10

34 22 38

34 45 00

34 36 15

34 25 45

34 23 00

34 40 34

34 36 20

34 35 15

34 32 02

34 44 30

34 22 42

34 25 05

34 21 00

34 26 00

Longitude

o i n

119 17 30

118 21 15 

118 53 00

118 25 20

118 31 54

118 30 46

118 31 36

118 56 50

119 13 40

119 14 50

118 25 40

119 00 55

118 47 45

118 44 15

118 28 42

119 08 00

118 33 30

119 18 45

118 57 45

118 46 53

118 16 30

118 27 00

118 31 27

118 42 45

118 24 28

119 22 15

119 04 30

119 05 15

Altitude 

(feet)

950

2,400 

508

3,250

1,267

1,325

1,270

400

800

750

3,400

400

650

675

1,480

5,400

2,041

658

430

2,425

3,200

2,100

1,580

4,200

1,900

750

275

1,100

February

27

*

0.41

1.65

1.05

1.54

1.00

.06

.28

*

.80

*

*

*

2.10

*

.44

*

*

.73

.78

Tr.

Tr.

*

2.10

*

*

*

28

1.18

.40

1.05

1.40

1.22

1.43

1.17

.73

.78

1.79

.81

.89

1.33

3.30

1.42

1.79

.80

.87

2.16

.82

.95

.87

1.65

1.95

.85

1.12

1.06

1

2.6

1.1

.9

1.8

2.3

2.0

1.8

1.9

1.9

1.2

1.9

1.7

1.5

2.2

*

1.7

2.4

2.3

2.1

.9

1.6

1.7

1.5

3.1

2.2

2.1

2.3
Santa Paula Canyon, Rancho la Cuesta**

Saticoy Walnut Association

Saugus, Southern California Edison Co. substation

Saugus, State highway maintenance station

Soledad Canyon

Soledad Canyon, east of Hint Canyon

Thacher School, near OJai**

Timber Canyon, near Santa Paula

Upper OJai Valley

Upper OJai Valley near Summit School**

Upper Sespe Creek near Choro Grande**

Ventura

Vincent patrol s tation

Wagon Wheel Ranch, Aliso Canyon

 - » -

Wheeler Hct Springs**

San Luls Obispo Creek, and Santa Maria and

Santa Ynez River Basins

Alisal Ranch, near Solvang \

Betteravia

Buellton**

Buellton, State highway maintenance station**

Burchardi Dairy, near Solvang**

Cuyama Canyon, State highway maintenance

station**

Cuyama, State highway maintenance station

Cuyama Canyon, near Pine Canyon

Cuyama, ranger station

Gibraltar Dam

Cuadalupe

Happy Canyon Ranch**

Huasna

Junoal Reservoir, Santa Ynez River**

Lompoc project**

34 25 00

34 16 50

34 25 23

34 25 17

34 24 47

34 26 15

34 27 50

34 25 20

34 25 50

34 26 07

34 35 30

34 16 35

34 29 30

34 25 00

-

34 30 30

34 33 10

34 55 00

34 36 40

34 36 30

34 35 40

35 01

34 57 30

35 04

34 51 00

34 31 30

34 58 10

34 36 50

35 07 15

34 29 30

34 39 50

119 05 00

119 09 05

118 34 32

118 32 26

118 26 24

118 17 38

119 10 55

119 01 00

119 11 45

119 08 20

119 19 15

119 17 30

118 07 45

118 05 30

119 17 30

120 08 10

120 31 00

120 11 00

120 11 30

120 08 10

120 12

119 40 3'0

120 08

119 29 00

119 41 15

120 34 15

120 00 00

120 23 30

119 30 50

120 19 45

900

150

1,093

1,176

1,472

2,250

1,360

2,280

1,250

1,560

4,000

50

3,250

3,920

1,560

500

100

450

325

495

1,000

2,100

900

2,749

2,250

80

750

200

2,300

500

*

*

.58

.76

.85

.95

*

*

*

*

Tr.

*

1.00

1.07

*

*

.20

.20

_

.17

_

Tr.

_

2.23

.56

-

1.12

1.00

.77

.77

1.61

.56

1.04

1.42

1.07

1.10

1.20

1.08

.30

1.18

1.17

2.79

1.14

1.36

.18

1.65

.17

.04

*

.40

_

*

1.34

.19

.14

2.4

2.0

1.0

.7

1.4

1.2

2.0

2.5

2.7

2.6

1.8

*

.7

1.4

2.7

*

.4

.7

1.3

*

1.0

.7

1.0

.9

2.4

.2

*

2.6

1.0

»Included in next measurement. **Measured in the m
Table 1.- Daily precipitation, in inches, at standard gages for the period Fe

(Measured in the afternoon except as noted

Station

San Luls Oblspo Creek, and Santa Maria and

Santa Ynez River Basins Continued

Lompoc project**

Lompoc project**

Lompoc project**

Lompoc**

Los Alamos, State highway maintenance station

Maricopa

Mitchell Ranch, near Santa Ynez

Nipomo, 2 miles north of***

Nojoqui County Park'"**

Ozena

Pine Canyon guard station

Santa Barbara

Santa Barbara, State highway maintenance

station

San Julian ranch near Lompoc**

San Luls Obispo, State highway maintenance

station**

San Marcos Pass, Paintefl Cave

San Marcos Pass

San Marcos Pass, State highway maintenance

station

Santa Maria

Santa Maria, State highway maintenance

station**

Solvang**

Surf**

Suey Ranch

Union Oil substation, 4 miles north of

Nipomo**

Washington Grove Park

Latl tude

34 50 15

34 40 45

34 41 45

34 38 50

34 44 30

34 56 20

34 35 00

35 02 30

34 32 00

34 41 45

35 02 15

<34 25 00

34 24 30

34 31 20

35 16 45

34 29 20

34 30 00

34 32 00

34 56 50

34 57 00

34 38 10

34 40 50

35 00 00

35 08 30

34 54

Longitude

120 25 15

120 23 40

120 25 15

120 27 30

120 16 45

119 23 30

120 05 40

120 28 30

120 10 30

119 19 10

120 11 00

119 42 00

119 42 00

120 17 00

120 40 00

119 47 00

119 49 15

119 51 00

120 26 00

120 25 55

120 10 45

120 36 00

120 22 00

120 33 00

120 27

Altitude 

(feet)

250

250

500

100

550

3,700

5,000

350

750

3,680

_ .

125

40

1,000

250

1,250

2,250

1,300

200-

200

450

36

600

300

-

February

27

_

-

-

_

0.25

.23

*

.75

_

-

_

-

.13

-

_

-

»

*

28

0.14

.15

.14

.20

.16

.20

1.75

.16

.53

1.50

»

.86

2.50

.71

.22

.90

.81

1.03

.12

.19

.30

1.05

*

1.50

1

1.29

1.18

1.33

1.45

1.02

.84

1.14

.97

3.58

.52

^

2.23

2.25

3.31

1.13

2.30

4.14

3.23

.32

.94

1.53

.84

.23

»

1.00
Qreat Baaln

Mojave River Basin

Aldrlch Ranch, Pallett Creek, 2.5 miles

northwest of Devils Punch Bowl

Sennit Ranch

Big Pines Park, Apple Tree Flat

Big Pines Park

Big Pines, south edge of Jackson Lake

Big Pines, Sawmill Flat

Calivalli Farma, on Viotorville road 1 mile

north of Palmdale

Fairmont Reservoir

Lake Arrowhead

Lake Tweedy near Neenach

Lancaster, Union High School

Little Rock Creek, 1.5 miles below dam

Little Rock, at Juniper Hills

Llano

Munz Ranch, 14 miles west of Lancaster

Palmdale ,

Sawplt Canyon . 

Sawmill Mountain Ranch, 8.9 miles northwest

of Lake Hughes

Table Mountain

Trona

Valyermo

Victorville

Sal ton Sea Basin

Banning

Blythe

Cabazon shaft

Hurley Flat

Imperial

Indio

Palm Springs

Poppet Flats 

Raywood Flat

Snow Creek

San Gorgonio powerhouse

34 26 10

34 19

34 23 24

34 22 45

34 23 30

34 22 24

34 32 08

34 42

34 15

34 44

34 41 58

34 30 18

34 29 52

34 29 47

34 42 50

34 34 51

34 16 45 

34 43 15

34 22 53

35 45 30

34 26 50

34 30

33 55

33 35

33 54

33 52

32 50

33 43

33 50 

33 51

34 03

33 53

34 02 20

117 53 07

117 25

117 43 00

117 41 28

117 43 40

117 41 00

117 58 00

118 25

117 11

118 34

118 07 48

118 01 40

117 56 45

117 49 02

118 21 15

118 06 52

117 20 30 

118 35 00

117 41 05

117 22 00

117 51 30

117 21

116 53

114 38

116 48

116 47

115 36

116 12

116 34 

116 51

116 49

116 41

116 53 30

4,050

4,000

5,900

6,660

6,075

6,750

2,835

3,036

5,000

3,905

2,350

2,900

3,150

3,300

2,600

2,648

3,350 

3,700

7,500

1,656

3,740

2,713

2,330

268

1,770

3,600

-65

-20

584

3,600 

7,200

1,300

4,500

1.78

*

2.73

2.00

2.54

1.98

.82

*

.55

1.17

*

1.22

*

1.27

.65

*

* 

.68

1.80

.45

1.00

.21

*

.28

.37

.29

.77

.53

.49

.50

*

2.50

.72

5.50

2.68

2.59

2.08

2.22

,.30

1.65

9*40

1.87

.80

.43

1.62

.47

2.10

1.41

* 

1.51

1.40

.55

.98

.73

1.65

.23

1.37

2.00

.22

.16

.10

4.00

1.50

3.50

1.40

*

2.45

1.68

2.29

1.72

.68

1.83

2.33

.58

.45

1.06

.77

.58

1.61

.87

11.24 

1.29

.88

1.27

1.17

.68

1.27

.30

1.41

1.80

.28

*

.70

3.50

*

1.50

 Included in next measurement. ** Measured in the morning. 
Table 2.- Daily prpci

Station

Tia Juana, Otay, and Sweetwater River Basins

San Diego

Santa Ana, San Gabriel, end Los Angeles

River Basins

San Gabriel Mountains

Briggs Terrace, Pick ens Canyon.

Camp Baldy, San Antonio* Canyon

Chilao, 1 mile north of Newcomb Ranch

Clear Creek, 1.6 miles above junction with

Tujunga Creek

Crystal Lake, East Pine Flat

Henninger Plats, Mount Wilson toll road

Hoegee's coop, West Fork of Santa Anita

Creek

Loomis Ranch near Junction of North and

Middle Forks of Alder Creek

Monrovia Falls, Monrovia Canyon

Mount Gleason

Mount Wilson

Opid's camp, West Fork of San Gabriel River

Paooima flood-control dam

Pick ens Canyon

San Antonio guard station

San Dimas Experimental Forest, Bell-Volfe

San Dimas Experimental Forest, Tanbark

Flats

San Dimas Experimental Forest, Bell Canyon

San Dimas Experimental Forest, Fern Canyon

San Gabriel flood-control dam No. 1

San Gabriel flood-control dam No. Z

San Gabriel River at mouth of canyon

San Gabriel River, East Fork of

pitation, in inches, at recording gages for the peri

Latitude

0 | H

32 42 45

34 14 15

34 14 15

34 20 31

34 16 37

34 19 10

34 11 30

34 12 30

34 21

34 11 15

34 22 26

34 13 20

34 15 15

34 20 00

34 15 15

34 10 45

34 10 00

34 12 21

34 12 00

34 12 15

34 12 20

34 14 45

34 09 48

34 16 35

Longitude

0 | H

117 10 00

118 13 30

117 39 15

117 59 30

118 10 15

117 50 45

118 05 15

118 02 30

D18 03 00

117 59 00

118 12 20

118 03 2O

118 05 45

118 24

118 13 00

117 40 28

117 48

117 45 34

117 46

117 41 45

117 51 20

117 58 00

117 54 17

117 45 05

Altitude 

(feet)

87

2,310

4,320

5,585

3,100

5,740

2,650

2,750

4,300

1,450

5,450

5,850

4,350

1,700

4,250

2,450

1,880

2,700

3,100

4,800

1,251

2,335

800

2,500

February

27

al.06

1.24

1.44

2.09

1.49

2.20

1.46

2.20

1.23

1.49

1.35

2.81

2.37

.96

1.59

1.43

1.52

1.53

1.50

.32

1.81

2.31

1.52

1.02

28

0.31

6.20

6.49

3.90

6.35

6.60

5.84

11.13

2.06

7.60

3.73

9.19

7.39

3.56

6.58

5.10

- 6.27

6.33

4.68

7.12

5.93

7.29

4.69

3.95

1

0.71

.48

.81

.30

.82

.88

.70

.73

.44

.49

.22

.48

.53

.38

.19

.90

.42

.61

.33

.74

.40

.60

.61

.56
Sierra Hadre, 575 North Hermosa Avenue 

Sleepy Hollow Ranch

Switzer's carap 

Upper Haine* Canyon

San Bernardlno Mountains

Del Rcsa ranger station

Devil Canyon experimental station

San Fernando Vall»y

Chatsworth, Twin Lakes Park fire station 

Van ffuys, city warehouse, Aetna and Vesper 

Streets

Verdugo Mountains

Brand Park

Rossmoyne fire area, Qlendale

San R*fa«l Hills

£1 Sereno, 4566 Bedlllion Street 

Tamploo Street

San Qabrlel Valley

Azusa, Bonlta Street, west cf Cerrltos 

Avenue

California Instituts of Technology 

Newmark, Meread Hills, Southern California

Edison Co.

Pasadena, Central fire station 

Pasadena, Ohio and Euclid Streets

Pasadena, Sunset Reservoir 

Pasadena, Washington Street and Palm 

Terrace

Chlno Valley

Clarenont, Pomona College Observatory 

Etlwanda

34 10 15 

54 18 04

54 15 15 

34 16 18

34 10 

34 13 00

34 16 38 

34 10 48

34 11 19 

34 10 50

34 04 54 

34 05 30

34 06 24

34 08 16 

34 02 45

34 08 50 

34 07 43

34 09 43 

34 10 08

34 05 52 

34 08 15

118 OS 30 

118 06 42

118 09 15 

118 15 11

117 15 

117 19 40

118 36 12 

118 27 03

118 16 21 

118 14 40

118 11 02 

118 10 30

117 53 58

118 07 38 

118 07 43

118 08 47 

118 08 34

118 09 17 

118 08 12

117 42 34 

117 31 00

1,160 

3,600

3,000 

3,450

2,250 

2,700

1,249 

695

1,250 

1,500

553 

600

545

763 

375

852 

755

930 

1,010

1,190 

1,450

1.70 

2.04

M 

1.70

1.68 

2.00

.53 

1.26

1.44 

1.18

1.44 

1.59

1.32

1.74 

1.74

1.81 

1.39

1.58 

1.60

.86 

1.21

5.98

4.11

M 

6.00

1.32 

3.13

3.28 

2.90

4.56 

4.13

3.68 

3.47

3.43

4.64 

3.14

4.68 

3.66

4.49 

4.95

2.72 

2.85

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

a Includes 0.22 Inch on Feb. 26. M Record missing.
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

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rH

CO

rH

rH

CO

tS

rH

H

Ot

a

o

rH

H

ffl

CQ
Topanga, Malibu, and Callewiaa &re«k Basins

Leehuza, patrol station on Decker Road

Las Posas 'project, McCormick Ranch

Topanga Canyon, 4 miles south of Topanga

Bridge

Santa Clara and Ventura River Basins

Acton, North Branch of Escondido Canyon

Bouquet Canyon, Artesian Springs

Bouquet Canyon, Cherry Summit

Bouquet Canyon, on Bouquet Canyon road near

Lincoln Crest

Bouquet Canyon, at reservoir yard

Bouquet Canyon, Spunky Summit

Bouquet Canyon, East Spunky Summit

San Luis Obispo Creek Basin

San Luis Obispo i

34 04 50

34 IS

34 05 08

34 29 51

34 34 20

34 35 SO

34 35 00

34 35 10

34 36 00

34 36 30

35 17

118 52 38

119 02

118 35 58

118 15 56

118 22 05

118 23 40

118 18 20

118 21 40

118 23

118 21 45

120 40

1,530

747

3,075

3,650

2,975

3,600

3,000

3,500

3,725

250

.52

1.52

.53

.56

.45

.91

.42

.56

.67

.05

4.96

2.53

5.75

1.00

2.24

2.13

1.77

1.99

1.93

1.83

1.35

.9$

.50

.69

.07

.17

.12

.12

.12

.18

.14

.31

b Includes 0.03 inch on Feb. 26. M Record missing.
46 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

The amounts of precipitation as shown for the individual days are 

not strictly comparable, as the observations at the various stations 

were not always made simultaneously. Host of the amounts given in table 1 

represent the rainfall during the 24-hour period preceding the time of the 

daily observation. Rainfall occurring during the daylight hours, however, 

may be recorded under the date of occurrence if observations were made in 

the late afternoon, or under the date of the following day if readings 

were made in the early morning.

Recording rain gages are maintained near many of the standard rain 

gages for which data are given in table 1. The two gages are usually 

operated for the purpose of comparison, and frequently there is considerable difference between the catch in the two. It should be emphasized 

that only the records for the standard-can rain gages are presented in 

table 1. All recording rain-gage records are presented in table 2 in a 

form similar to that used in table 1. The stations in table 1 for which 

recording-gage data are given in table 2 are indicated by a footnote reference. As the amounts given in table 2 represent rainfall occurring 

from midnight to midnight, the arrangement of the records is capable of 

presenting several features of the storm not discernible from readings 

made at different times during the day at the standard gages. By reference to several precipitation stations having gages of both types (see 

tables 1 and 2), the difference resulting from either unequal catch or 

different times of reading will be readily apparent.

Preparation of isohyetal maps

Although most of the precipitation fell in two or more rather distinct storms, both storms occurred within the period February 27 to March 

4, which has been treated as one storm period in the preparation of the 

isohyetal map. The isohyetal map for the entire storm period was developed from the records of the standard rain gages' as given in table 1. 

The location of each rain gage and the total storm rainfall were plotted 

on topographic sheets. For areas where there were a large number of station records and changes in topographic aspect were pronounced, maps on a 

scale of 1 mile to the inch were used; such areas included the coastal 

slopes of the San Gabriel, San Bernardino, Santa Ana, Verdugo, and Santa 

Monica Mountains, and the San Rafael Hills. For the remaining areas, 

where there were either fewer precipitation records or greater uniformity 

in topographic aspect, as in the valley areas, the information was plotted 

on topographic maps having a scale of 4 miles to the inch. The final
METEOROLOGIC AND HYDROLOGIC CONDITIONS 47

isohyetal map, on a scale' of 4 miles to the Inch, is reproduced as plates 

11-13 in this report. In locating the position of the isohyetals, full 

use has been made of such relations as could be determined between altitude, topographic aspect, and storm precipitation. In his recent account 

of the storm, Daingerfield ^ states:

The San Gabriel and San Bernardino mountains, with their east-west 

trend, lying directly across the pass of the moisture-laden winds, performed the functions of fixed and permanent "fronts", mechanically accomplishing the chilling of tropical maritime air and precipitating its 

moisture. .

Under the conditions described, fairly definite relations between 

altitude and storm rainfall can reasonably be expected. Figure 5 presents an example of these relations. On the upper half of the figure, 

the storm rainfall for both the coastal and desert slopes of Mount Islip 

and vicinity was plotted, against altitude, and graphs were drawn to show 

the relation between altitude and rainfall. The relative position of the 

rain gages with respect to topography is indicated on the lower half of 

this figure. Also included on the graphs, for the purpose of comparison, 

are records of a few gages located in the Santa Ana and San Bernardino 

Mountains. These graphs indicate that the storm rainfall on the coastal 

side of Mount Islip varied at a rate of about 3 inches per 1,000 feet of 

change in altitude and on the desert side at a rate of about 6 inches per 

1,000 feet, although as discussed in the following section, "Local storm 

characteristics", the altitude-rainfall relations were not so well defined in all parts of the area as in the part represented by figure 5.

In drawing the isohyetals, an effort was made to obtain the altituderainfall relations throughout the storm area, but there are many purely 

local conditions that seem to obscure any such relation. This is especially true in the mountains, where for nearly every storm many small 

areas show consistently higher or lower rainfall than the surrounding 

areas. The Los Angeles County Flood Control District has observed many 

such areas within the county and has maintained standard or recording 

rain gages in them for a number of years. In some parts of the mountains, 

therefore, there is perhaps a tendency to have a disproportionate number 

of gages indicating spec ial conditions as compared with the number indicating normal conditions

10 Daingerfield,

As rain gages in the mountains must generally

be located at or near places of human habitation, it is often difficult 

to arrange for the collection of records in desirable but remote places.

. H., Southern California rain and flood, February

27 to March 4, 1938: Mcnthly Weather Rev., vol. 66, no. 5, p. 139, 1938.
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

9,000

8,000

7,000

6,000

5,000

4,000

3,000

2,000

1,000

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 

Precipitation, in Inches, February 27 to March 4, 1938

8,000

Figure 5.- Relation between altitude and precipitation in the vicinity of Mount Isllp 

and schematic cross sections showing relative position of rain gages.
METEOROLOaiC AND H2DROLOGIC CONDITIONS 49

For most drainage areas In southern California, each rainfall observation for the storm period was plotted against altitude, and the relations were developed in a similar manner to those indicated on figure 5. 

In areas that failed to show definite relations, a series of parallel 

curves indicating a change in rainfall of 3 inches per 1,000 feet of .difference in altitude were passed through each observation. With such an 

altitude-rainfall relation established, the construction of the isohyetal 

map was somewhat simplified. Starting with the recorded precipitation at 

the various stations and using the indicated altitude-rainfall relation, 

points for fixing the position of each isohyetal were located at right 

angles to the land contours above and below each rain gage. The isohyetals were, in the main, drawn parallel to ground-surface contours, with 

gradual or abrupt transitions according to the influence of topographic 

features.

In those basins where there were few precipitation stations, especially in the headwaters of the Ventura, Santa Clara, and Cuyama Rivers, 

the location of the isohyetals may be subject to considerable error. 

Likewise, the isohyetal map for much of the desert region, such as the 

Deep Greek and West Pork of Mojave River Basins, may not represent actual 

conditions. In parts of the area, the isohyetals have been shown as 

dashed lines to indicate that their position is uncertain.

Table 3 shows for each of 22 drainage areas listed in table 1 the 

number of rain gages; the approximate area in square miles; the range in 

altitude of the rain gages and of the drainage area; the average precipitation over the area during the storm period February 27 to March 4 obtained by planimetering the area between each isohyetal; and a statement 

of opinion as to the probable accuracy of the isohyetals according to the 

classifications well defined, fairly well defined, and poorly defined.

Local rainfall characteristics

Analysis of the precipitation records used in the preparation of the 

isohyetal map shows that certain areas have rainfall characteristics that 

appear to be related to local altitude and topography. Some of these 

areas and their individual characteristics are described as follows:

Some of the heaviest rainfall occurred just over the 5,000- to 6,000- 

foot divide of the south frontal ridge that parallels the main range of 

the San Gabriel Mountains. The upward movement of the moist tropical 

air mass, caused by the blocking of its passage eastward by these steep 

coastal slopes, apparently continued after the mass passed the divide and
Table 3.- Summary of information regarding distribution of standard rain-gage records for storm 

Region

Pacific slope

Tla Juana, Otay, and Sweetwater Rivers a

San Diego and San Dlegulto Rivers

San Luls Rey and Santa Margarlta Rivers

Allso and San Juan Capiatrano Creeks

Santa Ana, San Gabriel, and Los Angeles Rivers

San Gabriel Mountains 

San Bernardlno Mountains 

San Fernando Valley 

Verdugo Mountains 

San Rafael Hills

San Gabriel Valley 

Chino Valley 

Upper Santa Ana Valley 

Jurupa Basin 

San Jacinto River

Temescal Creek

Santiago Creek 

Coastal plains

Xopanga, Mallbu, and Calleguas Creeks

Santa Clara and Ventura Rivers

San Luls Oblspo Creek and Santa Maria and Santa 

Ynez Rivers

Great Basin

Mojave River

Salton Sea

. Area

Square miles

948

1,089

1,656

374

556 

300 

244 

26 

21

279 

256 

205 

160 

732

212

85 

1,040

591

1,970

1,861

_

-

Range in altitude 

(feet above m.s.l.)

0 to 6,515

0 to 6,515

0 to 6,400

0 to 5,680

700 to 10,080 

1,480 to 11,485 

400 to 1,821 

600 to 3,126 

500 to 1,888

170 to 1,500 

500 to 2,250 

900 to 1,900 

700 to 3,000 

1,270 to 10,080

700 to 5,680

420 to 5,680 

0 to 2,000

0 to 3,050

0 to 8,800

0 to 6,828

_

-

Numbe

22

34

25

11

103 

21 

38 

6 

8

57 

25 

16 

4 

17

11

6 

151

39

66

40

eJ&

11

a Data refer to area in United States only.
METEOROLOGIC AND HYDROLOGIC CONDITIONS 51

resulted in the condensation and excessive precipitation of its moisture 

on the northern slopes of these ridges. The very heavy precipitation at 

such stations as Opid's camp, Arrowhead Lake, and Hoegee's camp may be 

explained in part by such topographic influences.

The effect of local conditions and of differences in exposxire of the 

gages Is Illustrated by rainfall records in the vicinity of Julian, where 

three gages within a radius of 3 miles and with a difference in altitude 

of less than 500 feet showed a variation In rainfall of 5.8 Inches. So 

wide a divergence suggests that the isohyetals may only roughly represent 

actual conditions.

An example of the effect of mountain ranges on rainfall Is indicated 

by the records from the rain gages in the San Luis Rey River Basin. Two 

gages at Mesa Grande, at an altitude of more than 3,000 feet and on the 

coastal slope of the range, indicated a rainfall in excess of 16 Inches. 

The gage at Henshaw Dam, in the San Luis Rey River gap between the ranges, 

showed similar precipitation. At Warner Springs (altitude, 3,165 feet), 

less than 10 miles east of the coastal range, there was only 8.73 inches 

of rainfall.

The low precipitation in the area around Riverside and in parts of 

the San Jacinto River Basin may be ascribed to the influence of the Santa 

Ana Mountains on the incoming maritime air mass, an influence similar to 

that indicated for the mountains near Warner Springs.

The abrupt changes in topography and altitude in the San Gabriel 

Mountains, who*e runoff Is tributary to the Santa Ana, San Gabriel, and 

Los Angeles Rivers, Introduce great difficulty in the development of isohyetals. Rainfall data for this area, however, are more complete than 

for any other mountainous section of southern California.

The altitude-rainfall relations for the vicinity of Mount Islip are 

shown on figure 5. Similar conditions were assumed to apply in all 

places where the individual observations checked this curve reasonably 

well. For example, the total rainfall on the divide at the head of Pickens Canyon, at an altitude of 4,250 feet, was 17.36 inches, but Z\ miles 

north, at Tujunga flood-control dam, at an altitude of 2,050 feet - or 

2,200 feet lower - the total was 20.36 inches. The rainfall recorded at 

the Tujunga flood-control dam is considerably greater than the amount 

normally to be expected for this altitude. (See fig. 5.) This unusually 

heavy rainfall nay result from the effect of the steep mountain canyon on 

the upward movement of the warm, moisture-laden maritime air masses, 

which apparently continue their upward course for some distance over the
52 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

ridge. The accompanying chilling process would thus produce excessive 

precipitation for a short distance beyond. Likewise, at Opid's camp, 

(altitude, 4,350 feet), 3 miles northwest of Mount Wilson, the rainfall 

was 27.27 inches, as compared with 26.23 inches at Mount Wilson (altitude, 5,850 feet). Actually there was a zone of heavy rainfall north of 

.the frontal ridge and paralleling the mountain range that extends for a 

distance of about 20 miles from Tujunga flood-control dam to the junction 

of the East and West Forks of the San Gabriel River.

With the exception of the rainfall of 32.20 inches at Kelly's Kanp 

(altitude, 8,300 feet), the heaviest precipitation in the southern California area was 30.08 inches at Hoegee's camp (altitude, 2,750 feet), 

which is located on the east side of a north-south mountain spur formed 

by Mount Wilson and Mount Harvard in the West Fork of Santa Anita Creek. 

Inasmuch as the tropical air mass seemed to move eastward, this short 

spur extending across the path of the storm may have produced a condition 

similar to that already described.

Similar characteristics were observed for this eame group of stations during the 2-day storm period of December 31, 1933, to January 1, 

1934, known locally as the "New Year's storm of 1934", when 19.20 inches 

of rain fell at Hoegee's camp. This exceeds by 1.10 inches the rainfall 

for the maximum 2-day period in the storm of February 27 to March 4, 1938. 

At Opid's camp, the rainfall of 17.21 inches during the "New Year's storm 

of 1934" was 0.12 inch less than that during the maximum 2-day period for 

the 1938 storm. A similar comparison of these two storms at the Clear 

Creek station and at Tujunga flood-control dam shows an excess of only 

about 3 inches for the 1938 storm. At Mount Wilson, the rainfall of 

14.69 inches for the 1934 storm was but 1.13 inches less than that for 

the maximum 2-day period during the 1938 storm.

A group of rain gages,including those at Mount Qleason (altitude, 

5,450 feet), Chilao (altitude, 5,585 feet), and Loomis Ranch {altitude, 

4,300 feet), are located about 10 miles directly north of this area of 

extremely heavy rainfall, to the west of Mount Islip and somewhat nearer 

the ocean. They indicate that considerably less rain fell in this area 

than In areas of comparable altitude on the frontal range. Mount Qleason 

had a rainfall of 17.54 inches at an altitude of 5,450 feet, as compared 

with 25.0 inches for that altitude as indicated by the Mount Islip 

altitude-rainfall relations. The greater rainfall at Mount Islip may be 

explained, in part, by its greater height and by the fact that it is approached on the coastal side by two straight north-south canyons, the
METSOROLOGIC AND HY.DROLOGIC CONDITIONS 53

canyons of Bear Creek and North Pork of San Gabriel River, which are more 

than 7 miles long. The prevailing winds are mainly from the south and 

are believed to have caused free movement of the moisture-laden air mass 

up these canyons, with heaviest rainfall at the head of the canyons as a 

result of the more rapid upward movement of air currents there. Loomis 

Ranch showed the least rainfall of the stations in this group, a fact 

which may be attributed to its lower altitude. During the 1934 storm, 

also, Loomis Ranch had a lower rainfall than the nearby stations.

Each station in these several groups showed characteristics during 

the 1938 storm similar to those it showed in the 1954 storm, indicating 

that as a result of local topographic conditions certain localities have 

a tendency toward predominantly lighter or heavier rainfall as considered 

in relation to each other. There are undoubtedly other localities 

throughout the southern California mountains that possess similar characteristics but because of insufficient rainfall records have not as yet 

been identified.

In the San Bernardino Mountains, also, are found local conditions 

that are likely to affect the rainfall of surrounding areas. The rainfall shown by the Plunge Creek gage (altitude, 6,000 feet) is almost 

identical in amount with that to be expected from the normal altituderainfall relation indicated on figure 5. Many of the San Bernardino Mountain stations, however, show considerably less rainfall than that indicated on figure 5 for their respective altitudes.

As indicated in the analysis of the observations from stations similarly situated in the San Gabriel Mountains, records from stations affected by local conditions are representative of relatively small areas that 

may receive comparatively light or heavy rainfall with a considerable degree of regularity. Because of the scarcity of gages elsewhere, such 

observations are of necessity assumed to be representative of many more 

areas than those to which they actually apply.

Isohyetals in Bear Valley and parts of Cajon Pass are not so reliable 

as in the remainder of the San Bernardino area, mainly becauee of laclt of 

precipitation data.

Rainfall at the base of the Verdugo Mountains, between San Fernando 

and La Canada Valleys, also showed considerable variation, caused probably by the local topography. A poorly defined altitude-rainfall relation indicated that the rainfall varied from 8.5 inches for the 1,000- 

foot altitude, in the western part, to 13 inches for the same altitude im 

the eastern part. An isohyetal map of the New Year's storm of 1934,
54 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

prepared by the Los Angeles County Flood Control District, shows characteristics of distribution very similar to those of the 1938 storm.

The effect of local topography is strikingly illustrated in figures 

6 and 7 which show four topographic cross sections of the southern California coastal plain, with the recorded rainfall for the 1938 storm 

plotted directly above them. One cross section is of an area in Ventura 

County, and the others of areas that cross the basins of Los Angeles, San 

Gabriel, Santa Ana, San Luis Rey Rivers and Temecula Creek. In none of the 

areas represented by the sections shown does the highest rainfall appear 

to have occurred at the point of highest altitude.

San Dimas Experimental Forest

The San Dimas Experimental Forest, located in the Sierra Madre Mountains northeast of Glendora, covers 17,000 acres and includes the entire 

drainage basins of San Dimas and Dalton Canyons above the flood-control 

dams maintained by the Los Angeles County Flood Control District. The 

investigation being conducted by the United States Forest Service in this 

area involves a determination of the relation of the chaparral vegetation 

to the yield of usable water from mountain drainage basins and of the extent to which this vegetation reduces flood runoff and erosion. Exact 

measurements of precipitation and runoff are necessary for the solution 

of these important problems. The entire area has been divided into two 

major basins, which, in turn, are subdivided, into 10 component areas of 

1 to 14 square miles each.

Rainfall is measured at the end of each storm at about 300 gages 

spaced half a mile apart along a system of trails built on the contours 

at altitudes of 2,100, 3,100, 4,100, and 5,100 feet. In addition, records of rainfall intensity are obtained from 15 recording rain gages distributed throughout the area in situations as nearly equal as possible 

both as to altitude and area.

Through the" cooperation of Dr. E. I. Kotok, Director of the California Forest and Range Experimental Station, J. D. Sinclair, silviculturist 

in charge of the San Dimas Experimental Forest, and members of their 

staffs, an isohyetal map for the storm period February 27 to March 4 in 

the San Dimas Experimental Forest was drawn. (See fig. 8.) On this map 

is a random cross-section line through the area, showing rainfall and altitude. The extent to which local influences may obscure the relation 

between altitude and rainfall is clearly evident from this map. An 

altitude-rainfall relation developed under these conditions is limited in
-?aeific Altitude, in feet 

Ocean

Pacific Alti

an 

s-s

a 

a

>ff

<g§

^cag

m §,

W 

Hg

»£ 

H**d

< H-

!>

Precipitation, in inches
56 FLOODS OF MARCH 1958 IN SOUTHERN CALIFORNIA

n_ 15 20 * 

Distance, in miles

Figure 7.- Cross sections showing altitude and precipitation In basins of Santa Ana and 

Sn.n Luls Rey Rlyers and Temeoula Creek.
METEOROLOOIC AND HXDROLOaiC CONDITIONS 87

25

tOo

t-tea

Precipi

t-to

5,000

4-> 

0

£ 4i_000

S

+ 3,000 

1

3 2,000

i-t

<

1,000

Cross section A-A

u i as 4 B e Y 

Distance, In miles

Figure 8.- Isohyetal map and cross sections showing altitude and precipitation In San 

Dlaas Experimental Forest.
58 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Its application, and isohyetals based strictly on such a relationship, 

especially in areas where the data are meager, should be used with caution.

Chronologic distribution

The precipitation of the storm of February 27 to March. 4, 1938, was 

marked by four phases. The first phase occurred on February 27 and 28. 

From the morning of February 27 to the early hours of the morning of February 28 the rain was light and intermittent. During the remainder of 

February 28 the precipitation was generally continuous and Intense. Many 

of the precipitation stations, especially those near the coast, reported 

maximum intensities of short duration during this phase. In the second 

phase, on March 1, no appreciable precipitation occurred from 1 a.m. to 

10 or 11 p.m. This lull was followed by the third phase, on March 2, 

when the rainfall was extremely heavy. At stations In the headwater areas 

of many streams, especially the Los Angeles, San Gabriel, and Santa Ana 

Rivers, the maximum 24-hour rainfall was the greatest on record. Some 

stations recorded maximum rates during the morning of March 2 and others 

recorded them during the afternoon. The data obtained during the storm 

were not so complete for areas north and south of these basins, but available observations Indicate that the storm there was less severe than in 

the intermediate areas. Following the intense rain of March 2, the storm 

entered its fourth and closing phase on March 3, when light and intermittent rains continued generally until late afternoon. During the period 

March 4-10 there was either no rainfall at any station or too little to 

be significant.

The four phases of the storm are readily visualized by noting the 

mass curves of accumulated rainfall at several representative stations, 

as shown in figure 9. (Mass curves of accumulated precipitation for typical groups of stations are shown in fig. 13.) The periods of maximum intensity are also clearly indicated in figure 10, which shows the hourly 

precipitation at representative stations. The general eastward movement 

of the center of the storm is indicated by comparing, the mass curves for 

the Topanga and Sleepy Hollow stations in figure 9. During the period of 

intense precipitation on February 28 the Topanga station showed considerably more accumulated rainfall than the Sleepy Hollow station, 32 miles 

to the northeast. This excess continued until shortly after noon on March 

2, when the precipitation in the Topanga area began to slacken, but that 

in the Sleepy Hollow area did not slacken until several hours later. The
HETEOROLOQIC AND HmROLOGIC CONDITIONS

February 27 

Figure 9.- Mass

February 2B March. 1 March 2

curves of accumulated precipitation at representative stations. 

February 27 to March 3, 1938.
60 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

0.50

February 27 February 2S March 1 March 3 March 3

figure 10.- Hourly precipitation nf representative stations, February 27 bo March 3,

1938.
METEOROLOGIC AND HXDROLOGIC CONDITIONS 61

extremely heavy 12-hour rainfall, especially in the mountains, is graphically indicated by the mass curves of precipitation at Hoegee's camp and 

Opid's camp. The mass curve for the San Luis Obispo station indicates 

that this station was outside the area of heavy precipitation. Table 4, Vr

which gives the percentage of the total storm rainfall occurring at representative stations during each day of the storm, presents also data on 

the periods of rainfall and indicates the variations in the storm characteristics of the affected region. The average of 58 records from recording gages in the Los Angeles, San Gabriel, and Santa Ana areas, included 

in this table, shows that about 52 percent of the total rainfall fell on 

March 2, which was the day of maximum rainfall during the storm.

Table 4.- Percentage of total storm precipitation on Indicated days at 10 

representative recording stations in Los Angeles and adjacent counties 

for the period February 27 to March 5, 1958

Station

Hoegee's camp, West Fork of Santa

Anita Creek

Opid's camp, West Fqrk of San Gabriel River

Sleepy Hollow Ranch

Topanga Canyon, 4 miles south of

Topanga Bridge

Del Rosa ranger station

Los Angeles, Sixth and Main

Streets

Claremont, Pomona College Observatory

Santa Ana, Orange County Flood

Control District office

San Diego

San Luis Obispo

Average of 63 recording gages

February

27

7.4

8.7

11.0

10.2

14.5

13.3

8.6

15.7

21.3

1.4

9.8

28

37.5

27.1

22.0

38.5

11.5

25.8

27.2

25.2

7.8

36.8

29.7

March

1

2.4

2.0

1.4

4.6

6.0

4.3

3.8

10.7

18.0

8.4

3.6

2

5Q.1

57.6

61.3

45.0

59.3

53.2

54.5

45.8

39.5

38.4

52.0

3

2.6

4.6

4.?

1.7

8.7

3.4

5.9

2.6

13.4

15.0

4.9

Total 

(inches)

29.71

27.23

18.62

14.92

11.54

11.06

9.99

6.07

3.95

3.67

Rainfall intensities

Among the first recording rain gages to be established outside the 

Los Angeles metropolitan area were those located in the San Gabriel Mountains. Prior to 1916 the United States Forest Service, the United States 

Weather Bureau, and the County of Los Angeles, entered into a cooperative 

agreement that provided for the establishment and operation of certain 

recording rainfall stations in the mountain areas. These stations were 

located at Mount Wilson, Sister Elsie Peak, Haines Canyon (upper station), 

and Alder Creek (Loomis Ranch). The gages at Haines Canyon and Sister 

Elsie Peak which were some distance from human habitation, were inspected 

weekly by employees of the United States Forest Service. This duty was 

later assumed by the Geological Survey and more recently by the Los Angeles County Flood Control District.
62 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The hydrologic division of the Los Angeles County Flood Control District was created in 1927, and Walter J. Wood, the present chief hydraulic 

engineer, and Finley B. Laverty and F. H. Hays, former chief hydraulic 

engineers, were largely responsible for establishing the large number of 

recording rain-gage stations now in operation in Los Angeles County. As 

a result of the combined activities of the various agencies previously 

referred to, more than 60 recording rain gages were in operation during 

the storm of February 27 to March 4, 1938, in an area covering about 

7,000 square miles and including both mountains and valleys.

In order to facilitate a more detailed analysis of the rainfall records, the hourly records of rainfall at the automatic recording gages are 

assembled in table 5. The stations are the same as those for which the 

daily precipitation is given in table 2.

Tables 6 and 7 present data deduced from the original records on the 

intensity of the precipitation during the storm period February 27 to 

March 4, 1938, and its duration at different rates of intensity. Table 6 

shows the number of hours in the storm period during which the intensity 

exceeded the given rates, which range from 0.2 of an inch to 1.4 inches 

per hour, and also the total amount of precipitation that fell at rates 

in excess of the indicated rates. Table 7 shows the maximum rates of 

precipitation, in inches per hour, for specified periods, ranging from 5 

minutes to 120 hours, within the storm period. In table 7 the specified 

periods are continuous, but in table 6 they may be either continuous or 

discontinuous. The basic data for tables 6 and 7 were furnished, in the 

main, by the Corps of Engineers, United States Army, and the Los Angeles 

County Flood Control District.

In some localities, especially on the coastal plain, the maximum 

rates of precipitation for the short periods occurred on February 28, or 

outside the maximum 24-hour period of the storm, which corresponded in 

general to the calendar day March 2. Generally, at the stations given in 

table 5, each maximum period of 3 hours or longer occurred within the next 

longer maximum period.

The recording-gage records in the foothill and mountain areas have 

been analyzed, and five groups, A to E, inclusive, have been selected 

that seem to be more or less distinct in the total amount of rainfall, 

the relation between duration and average intensity, and the time of occurrence .
Table 5.- Precipitation, in inches, for period ending at Indicated t

Station

San I) lego

3nri+4. Ann. 3o.fi Gjibrlal. anA Loa Aflffftles Rivev

Baaina

San Gabriel Mountains

Brigga Terrace, Plolcens Canyon

Camp Baldy, San Antonio Canyon

Chllao, 1 mile north of Hewcomb Banah

Clear Creek, 1.6 miles above Jtmotion

with Tnjunga Creek

Day

27

28

liar. 1

2

Feb. 27

28

2

3

Feb. 27

28 

Mar. 1

2

Feb. 27

28 

liar. 1

2

Z

Feb. 27

28

2

S

A.M.

1

0.14

_

.07

_

.06

.14

~

.07

.12

.22

_

.04

.14

.03

.OS

.22

-

2

0.09

_

.01

_

.10

.06

.05

.07

.22

.07

_

.05

.20

.03

_

.06

.08

.04

3

0.04

.01

.11

.04

.16

.26

.01

_

.16

.16

.04

.10

.19

.12

.14

.15

.04

4

0.01

_

.19

.07

.36

.36

.04

.03

.25

.26

.07

.20

.11

.03

_

.15

.35

-

5

_

0.01

.04

.03

.16

.39

.09

.03

.30

.33

.05

.30

.18

.09

Mo

.47

.36

.10

6

0.02

.02

.01

_

.19

.33

.18

.02

.25

.38

.03

.12

.30

.01

'.10

.15

.39

.15

7

_

0.01

.05

.02

.37

.53

_

.02

.22

.52

.06

.20

.47

.05

Mo

 23

.41

8

_

0.02

.01

.12

.22"

.56

.01

.02

.26

.35

.12

.18

.43

.07

.10

.25

.10

.02

9

0.03

_

.10

.15

.35

.82

_

.12

.34

.73

.23

.17

.42

.08

Mo

.30

.31

.02

10

0.12

.05

.02

.16

.37

.97

_

.22

.20

.97

.20

.18

.61

.02

Mo

.17

1.58

.01

11

0.12

.06

.01 

02

.16

.26

.45

_

.14

.23

1.00

.20

.12

.52

.03

Mo

.28

1.40

.01

12

0.01

.05

-

.11

.17

.70

_

.06

.20

1.00

.21

.10

.45

.04

Mo

.32

1.15

.05

 Estimated II Beoord missing.
Table 5.- Precipitation, in inches, for -period ending at indicated time. Febr

Station

%ffltifi A r San Gihrlal. and Los Angelas Blvfflf

Baaing Continued

San Gabriel Ilountains Continued

Crystal lake, East Pine Flat

Henninger Flats, Mount Wilson toll road

Hoegee** camp, Vest Fork of Santa Anita

Creek

Loom! s Eanoh, near junction of North and

Middle Forks of Alder Creek

Monrovia Falls, Monrovia Canyon

Mount Qleason

Bay

Feb. 27

28 

liar. 1

2

3

Feb. 27

88 

liar. 1

2

3

Feb. 27

28

Mar. 1

2

3

Feb. 37

28 

Mar. 1

2

3

Feb. 27

28 

Mar. 1

2

Feb. 27

28

Mar. 1

2

3

A.M.

1

_

0.09

.25

.10

_

.10

.28

.18

_

_

.32

.15

.05

_

.26

.06

.01

_

.20 

.14

.22

_,

.01

.05

.18

_

2

0.02

.19 

.07

.12

.08

_

.08 

.16

.02

_

.07

.25

.21

_

_

-

_

.01

.04

.13

.16

_

.04

.13

_

3

0.09

.17

.20

.14

.08

.12

.16

.04

.09

.34

.37

.06

.03

.05

.03

.07

.09

.18

.25

_

.01

.24

.05

4

0.07

.30

.23

.06

.07

.23

.25

_

.09

.45

.42

_

.03

.06

.16

.02

.05

.33

.31

_

.04

.33

.05

5

0.07

.37

.34

.25

.05

.40 

.01

.35

.18

.05

.48

.58

.22

.05

.14

.30

.06

.04

.32

.39

_

.24

.01

.36

.01

6

_

0.24

.45

.17

_

.18

.37

.18

.02

.32

.47

.26

.01

.07

.30

.18

.02

.23

.48

_

.30

.35

.12

7

0.06

.71

.35

.10

.04

.43

.42

.01

.05

.60

.73

.02

.03

.10

.29

.11

.06

.39

.78

_

.12

.59

.23

8

0.14

.46

.73

.04

.13

.49

.40

_

.13

.59

.63

_

.08

.20

.28

.06

.14

.51

.36

.02

.19

.21

.02

9

0.10

.18

.79

.04

.12

.18

.88

.04

.15

.35

1.15

.08

.15

.10

.34

.02

.10

.34

.96

.10

.14

.64

.02

10

0.13

.37 

.01

.86

.02

.18

.35

.98

_

.19

.52

1.19

.02

.15

.06

.49

.02

.14

.30

.78

.29

.16

.61

.03

11

0.21

.42 

.02

1.00

_

.19

.24

.49

.04

.28

.56

.83

.07

.17

.01

.64

_

.20

-.30

.63

.16

.12

.50.

.06

12

0.14

.30

.93

.01

.15

.42

.66

.02

.14

.52

1.05

_

.15

.01

.49

.07

.10

.45

.50

.13

.41

.69

.02
METEOROLOOIC ARD HXDROLOSIC CONDITIONS

Ncn w H <o w r- inSIS

to to ft N ^1 n in BJ «o iv H to

H <D

S8sss §ss a ssss SSSg SN^S §858

i

tocoHioNNnio N<ON H<on CD t» n H o o <p o t- 

( <O rj rt H H in rj O OSi-l ° * i ^ OlD ° Oo> 'J " "S ^

o a t- ^t in

, ? «J m. ^ , , S , s

N O MR!

«rjn ^ in O iH t- NOC- t-l CO rt C-<on r-< to q> en «C\i 

ONH Of-IH OO^ONO OiHO OHO OHCO OH

§ gg S

rt O O H « 'C n I

°. ,a ,1,1, °.°. , H. r °.' I I I

t- o HO H OH

*? HS2P. £S t-Noo * <o M*t-^

 S °. S. , 8. i °. a «J H. S. , «? i m. i °.1 , 11

n * o> »NO> ^» vfno rtKin n m M i- *i fiHio oon o o .. o H m o o * o o to o o< 00

o co o

0\

> «o *o us

I l-t |H |H 113 I i

8 IN O 

H S3 S

tA I 

O <

B >S

O O

in if) IA o>

Si 10 . H O

us in oj H tn m 8

O1 H Ci O* o 

H . * O rt . P

in in

OO SS S

S 8 S 8 88*

!g N$

o <o in i- in o no>m <o^co

NNlOiHrtO HHO NNly

SS g Si

O^^tO C2tCO lOOt to9rj OK us ort IntQ

oo

AfMO^CDND- no ND-C> CM|T)£« Nf-4COrH 

HIOrJOiHiJo 'J'^ M*O ONIO ON'SP^C

Hc^

ON

O O3 I 

CJ 10

I CM H 1C 

> IH O iH

in H o* 10 H m w w ^ o PJ ^ * in

in K OHOC20 ON W ON WO OH WO

iH W in W C2H COO CO tO ^ M H t- ^» C\J <T> ^ H 0V *O O> ^ tOHHt^lA 

iH H tOO OH K H O H OHOOO O W HO OH HO OGMOHO

r- iH O ON5- ri^iSSS: HOH ONOHO sa.s

J

t^NH OOH1A E-tQtQIO 

MJ c3 O MNNO .i-l-^NO

I I I I
table 5.- Precipitation, in Inches, for neriod ending at indicated time. Febru

Station

Santa ATI* Saw A&'brlel nrtf Loa Amral t>.& River

Baaina Oont Inued 

San Gabriel Mountains Continued

San Dimas Bcperlmental Forest, Fern 

Canyon

San Gabriel flood -control dam Ho. 1 

San Gabriel flood-control dam Ho. 2 

San Gabriel Slver at mouth of canyon 

Son Gabriel Elver, East Fork of 

Sierra lladre, 575 North Hermosa Avenue

Day

Feb. VI

28

Mar. 1 

2 

3

Feb. 27 

28 

Mar. 1 

Z

s

Feb. 27 

28

liar. 1 

2 

3

Feb. 27 

28 

liar. 1 

2 

3

Feb. 27 

28 

liar. 1 

2 

3

Feb. 27 

28 

ttur. 1 

2

A«M»

i

0.16 

.52 

.26 

.02

.15 

.20 

.30 

.02

.18 

.20

.17 

.09

.17 

.08

.16 

.06

.14

.29

2

0.28 

.04 

.12 

.04

.02 

.17

.21 

.05

.02 

.14

.19 

.05

.02 

.08

.18 

.04

.06 

.07

.08 

.06

.12 

.12

.09

3

0.16

.18 

.06

.05 

.15

.24 

.06

.09 

.13

.30 

.04

.05 

.14

.26

.08

.10

.15 

.06

.13 

.16

.19

4

0.24

.30

.04 

.19

.28

.07

.29

.33 

.02

.04 

.14

.29 

.12

.03 

.14

.21 

.01

.20

.89

5

0.36

.36

.01

.25

.30 

.32

.05 

.28

.46 

.14

.17

.40 

.32

.02 

.17

.26

.21

.06

.39

.12

6

0.24

.42

.03 

.15

.45 

.40

.03 

.15

.55 

.16

.02

.15

.43

.18

.02 

.17

.34 

.38

.10

.44

7

0.32

.58

.04 

.25

.64

.06 

.40

.80

.04 

.15

.62

.02 

.17

.43 

.05

.03 

.32

.60

8

0.30

.34

.08 

.46

.58 

.01

.18 

.42

.50

.10 

.72

.87

.03

.30

.49

.11 

*.40

.38

9

0.38

.62

.18 

.32

1.02 

.01

.12

.35

1.15 

.04

.16 

.33

.63

.13

.66

.16 

 .40

1.16

10

0.26

.92

.22 

.43

.75 

.02

.15 

.44

1.15 

.02

.24 

.23

.36

.22

.68 

.02

.22 

 .40

.74

11

0.14

.80

.24 

.10

.42 

.01

.25 

.39

.63 

.02

.24 

.05

.13

.12 

.16

.66

.26 

*.43

.45

12

0.18

.56

.12 

.26

.62

.19 

.27

1.07 

.02

.12 

.12

.45

.04 

.16

.35

.14 

.06

.37
Sleepy Bolloir Baaoh

Switzer's oamp

Upper EEaines Oanyon

San Bernardlno Mountains 

Del Bosa ranger station

Devil Canyon experimental station

San Fernando Valley 

Chatsworth, Twin Lakes Park fire station

Tan Hoys, oity warehouse, Aetna and 

Vesper Street*

 Estimated.

Feb. 27

28

liar. 1

2

3

Feb. 27

28

liar. 1

2

3

Feb. 27 

28

liar. 1 

2

Feb. 27

28

Bar. 1

2

3

Feb. 27

Mar.

Feb. 27 

28

liar. 1 

2

Feb. 27

28

liar. 1

2

3

m

.01

.09

.06

.13

.12

.16

.02

.60

.10

-

_

.10

.02

.20

.01

.08

_

.03

.03

.05

.08

.09

.03

.02

.04

.02

.02

.04

.19

.01

.13

.02

.08

.04

.10

.14

.10

.19

.06

.12

.2*

.04

-

.04

-

.01

.26

.07

.02

.26

.03

.04

.24

.07

.22

.22

_

.22

.03

.40

:S

.10

.08

-

 .

.15

.24

.14

.40 

.04

.14

.38

.02

.21

.43

.15

.62

.02

.29

.43

.02

.14

.16

.08

.02

.17

.19

.06

.51

.01

.39

_

.07

.28

.16

.30

.13

.35

.04

.38

.24

.05

.08

.48

.10

.46

.09

.38

.07

.19

.30

_

.42

.05

.26

.40

.06

.08

.30

.26

.08

.05

.40

.10

.22 

.06

.13

.39

.10

.18

.50

_

.54

.17

.16

.20

.08

-

.32

.02

.07

.12

.56

.11

.30 

.10

.14

.32

.20

.16

.67

.05

1.46

.24

.21

.81

.08

.02

.34

.28

.15

.33

.30

.01

.20

.64 

.20

.20

.44

.20

.15

1.10

.01

1.13

.18

.26

.83

.14

-

.24

-

.12

.20

.60

.17

.28

.20 

.15

.07

.20

.22

.10

.60

_

1.61

.18

.31

.68

.14

.04

.38

-

.08

.20

.70

.12

.03

.24

.10

.09

.18

.23

.08

.93

.04

.86

.15

.17

.90

.10

.06

.34

-

.11

.20

.77

.06

.06

.40 

.17

.04

.60

M Record missing.
68 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

as^ss 8

4# CO *P tp COt Q Okfr-IOOk^t^1 ? 3 Sw Njo in«*«inHJH

n i4n*«o*|«3 rHn'io'JH

rH I H |rH

in m IH

K rt H o S 8

to w co

O O rH

in w *o

O 0 ft

*,,'«,

BS

N to to

O it) O

S

CO ^^ 

*H 1O *H ss

in in » CM rt rH « Ci

.3 . & g.

88

a a

Bj. 

*^.

» ,<!,

88

S 83

S3

ssa

8 S

II II8§a. saag

2 I g
California mtttnt* of technology

Heomark, Merced Hills, Sonthern California Biiaon Co.

Pasadena, Central fire station

Pasadena, Ohio and Build Streets

Pasadena, Sunset Heserrolr

Pasadena, Washington Street and 

Palm Terrace

Feb. 27

28

Mar. 1

2

3

Feb. 27

28

Mar. 1

2

3

Feb. 27

28

Mar. 1

Mar. 1

2

3

Feb. 27

26

Ifar. 1

2

Feb. 27

28

Mar. 1

2

3

_

.10

.16

_

.01

.09

_

.38

.12

_

.03

.10

_

.11

.09

_

.12

.09

-

.02

.07

.07

.03

-

.05

_

.07

.08

_

.09

.07

.03

.05

.06

.02

.09

.06

_

.05

.05

.21

.03

.09

.20

.04

.02

.20

.03

.04

.16

.08

.03

.17

.08

.06

.19

.01

.05

.22

.84

.02

.16

.35

.06

.19

.37

.05

.13

.39

.06

.19

.32

.05

.24

.34

_

_

.12

.46

.16

_

.05

.58

.05

.13

.63

.04

.08

.36

.04

.09

.44

.04

.12

.43

.01

.05

.12

.36

.02

.06

.35

.02

.12

.37

.01

.12

.06

.01

'.11

.29

.01

.16

.35

.13

.04

.32

.57

.07

.04

.55

.04

.38

.48

.04

.27

.03

.04

.44

.47

.05

.55

.46

.17

.12

.73

.45

.15

.85

.56

.15

.47

.31

.11

.73

.08

.16

.40

.49

.14

.24

.51

.02

.15

.28

.91

.28

.25

.41

.19

.18

.43

.15

.44

.01

.13

.30

1.13

.14

.28

1.06

.02

.22

.31

.70

.38

-

.18

.22

.05

.85

.21

.04

.60

.22

.16

.66

.20

.17

.85

-

.26

.08

.10

.28

.05

.06

.30

.16

.13

.22

.07

.08

.21

.22

.25

.26

.21

.19

.01

.1

.0

.2

.1

-

.1

.1

.1

.5

.1

.0

.4

.12

.12

.39

.15

.19

.49

.07
Table 5.- Precipitation. In Inches, for period ending at Indicated time, Febru

Station

Santa Ana. San Qabriel. and Los Angeles Elver

Basing. Cont Inued

Chlno Valley

Claremont, Pomona College Observatory

Etlwanda

Jurnpa Basin

Citrus experiment station, University of

California

Santiago Creek Basin

Santiago Dam

Day

Feb. 27

28

2

3

Feb. 27

28

Me«* 1

2

Feb. 27

28 

liar. 1

2

27

28

2

Feb. 27

28

2

3

1

0.06

.10

.01

.04

.12

.02

.13

.01

.02

«Q

.11

.03

.01

A*

.05

-

2

0.01

.02

.09

.01

.01

-

.15

.03

.02

.01

.05

_

.11

.03

-

3

_

0.19

.18

.02

_

.10

.13

.01

.01

_

.16

.06

.01

.18

.34

.01

4

_

0.19

.30

.11

_

.20

.30

.01

.06

.07

_

.22 

.01

.29

.01

.11

.26

.02

5

_

0.10

.43

.16

.02

.12

.37

.02

.10

.19

.01

.07

.46

.03

.12

.19

.10

A.M.

6

0.01

.04

.46

.05

.05

.05

,.43

.04

.03

.20

.01

.10

.24

.10

.03

.16

.09

7

0.05

.01

.53

.02

.08

-

.30

.04

.01

.05

.06

-

.14

.11

-

.21

.01

6

0.17

.30

.43

.13

.10

.20

.35

.05

-

.01

.19

.02

.15

.11

.01

.31

.01

9

0,20

.15

.40

.03

.14

.14

.53

.03

-

.01

.18

.02

.18

.14

.03

.42

.03

10

0.06

.04

.16

-

.02

.09

.62

.06

-

.10

f\9

.11

.02

.29

.12

.03

.26

.02

11

0.06

.06

.33

-

.05

.12

.17

.02

-

.20

.04

.04

.05

.16

.07

.22

-

12

0.02

-.03

.12

-

.04

.10

.27

.05

-

.17

.15

.04

.24

.17

-

.28

.01
SllTerodo ranger station

Ooastal plains

Bel-Air, administration building

Severly Hills, olty hall

Fuller-ton evaporation station

Griffith Park Borsery, Horth Ooamonwealth Avenue

Hanoook Park, 5801 Wllshire Boulevard

Lagtma Bell

Mar. 1

2

3

Feb. 27

28

Mar. 1

2

3

Feb. 27

28

Mar. 1

2

3

Feb. 27 

28 

Mar. 1

2

3

Feb. 27

28

Mar. 1

2

3

liar. 1

2

3

Feb. 27

.03

.01

.09

.03 

.01

.03 

.01

.86

_

.14

.04

.19

-

.02

.19

.10

il

.02 

.05

.10

.02

.04

.02

.09

.02

.06

.07

_

.08

.01

.05

.11

.22

.02

.01

_

.13

.01

.04

.01

.06

M

_

.02

.11 

.01

.06

_

_

.12

.03

-

.07

.02

.18

.01

.33 

.02

.01

.37

.01

.03

.OS

_

.31

.01

.01

.07

.07

M

.09

.02

.29 

.01

.06

.08

_

.24

.05

.11

.09

.02

.12

.01

.31 

.10

.08

.01

.47 

.07

.08

.17

_

.55

.04

.01

.19

.45

M

.06

.19

.39 

.02

.01

.14

_

.51 

.04

_

.16

.37 

.03

.03

.11

_

.26

.06

.23

.68 

.01

^

.07

.01

.70

.04

.01

.09

.54

M

.02

.07

.49

.01

.05

_

.49 

.07

_

.04

.58 

.05

.08

.05

.01

.19 

.22

.07

.51 

.05

^

.23

_

.62

.03

.01

.05

.39

M

 ,

.13

.02 

.09

 04

.21

.05

.43 

.02

.05

.06

.49 

.09

.05

.01

_

.19 

.02

.22

.67

.06

.67

.03

.90

-

.04

-

.19

M

.04

.23

.94

.15

.74

.02

.81

.09

-

.42

.09

.01

_

.34

.09

.34

.95

.13

.36

.02

.80

.01

.11

.03

.06

M

.10

.44 

.06

.86

.18

.20

.05

.87

.14

.24

.11

.03

.07

_

.60

.14

.26

.33

.26

.28

.01

.50

.01

.23

.03

.22

H

.17

.21

1.00 

.02

.18

.12

.04

.29

.34

-

.26

.05

.08

_

.86

.28

.27

.41

.15

.05

_

.21

.01

.19

.02

.10

M

.19

.08

.44 

.01

.13

.03

.14

.89

.37

-

.14 

.05

.05

.15

_

.25

.14

.03

.10

.16

.05

.01

.03

-

.04

.OS

.02

M

.16

-

.07

.13

.03

.01

 04

.26

.01

.01

.0

.0

_

.2

.1

.1

.2

.1

.0

_

.1

-

.1

.0

.1

U

.1

.0

.3

.0

_

.0

.2

.1

-

.1

H Record missing.
72 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

t* tO CO CO c0l *O W O* «dt O f4| «O tO 60 tO CO tOl t* O W 60 O Ql O W 4 W H IO| 0

^J* CO ^ CO Wl O t* t* tO «O r-ll t* O* IO *C > ^ O IO i-l t* ^ ^1 tO U) Ot Ot tQ C^ IN

iHcJ*«?li4 iHH*W*|l> *H*WJ»O HH*W*|«O *J*IOi

888*1

ej * n *|i

in O> 

rt iH

sa

,1,

88

a s

i g , 8.8 ,, 8.,

88

s g a

**

88 88

H

<o

«9 S rt «* 5 S e e

ss gs 8 £ 8

 * « c. ra o

r! , °. s. ,-1 , ,1

ggSSS

£'

i i ii i J

Los C

Santa Dist
fopanga Canyon,

Bridge

Santa Olara

4 miles south ef Topanga

,

Acton, Horth Branch of Eeoondido Canyon

Bouquet Canyon,

Bouquet Canyon,

Bouquet Canyon,

Lincoln Crest

Bouquet Canyon,

Artesian Springs

Cherry Sunrait

Bouquet Canyon road near

at reservoir yard

Pel. 27

28

Har. 1

2

3

Pel. 27

28

Har. 1

2

3

Pel. 27

28

Har. 1

2

3

Beg. 27

28

Mar. 1

2

3

Pel. 27

28

Har. 1

2

3

Feb. 27

28

Mar. 1

2

3

_

.05

.01

.21

.03

~

_

-

.04

-

.06

.01

.06

-

-

.02

_

.04

.01

.19

-

.05

.01

-

.05

.01

.06

.01

.04

.02

.04

.03

.07

.14

_

.46

.01

.02

.01

.

.01

.19 

 06

.03

.11

.01

.12

.06

.12 

.32

.11

.32

.01

.59

.04

.OB

.01

.08

.25 

.06

.OB

.22

.06

.17

-

.20

i a

.07

.10

.01

*.64

.06

.14

,80

.20

.25

.13

.29

.10

.22

.18

.25

_

.27

_

*.66

.03

.10

.11

.12

.36

.10

.23

.09

.28

.15

.25

.05

.36

_

*.66

-

.04

-

.01

.10

.17

.14

.18

.OB

.17

.01

.22

.10

.36

_

1.10

.04

.02

.02

.06

.14

.32

.05

.16

.01

.13

.04

.06

.38

.80

.78

.04

.55

.07

.02

.22

.06

_

.04

.54

.07

.45

.04

.02

.44

.02

.03

.30

.21

.13

_

.16

.15

.03

.16

.02

.04

.12

.25

.07

.10

.44

.11

.12

.48

.02

.10

.25

.15

.22

.01

.19

.10

-

.18

-

.15

.08

.25

.11

.12

.26

.21

.07

.20

.01

.OB 

no

.22

.06

.1

_

.5

.0

.0

.2

.0

.07

.07

.4

.0

.0

.4

.0

.0

.3

.0

.0

.5

 Estimated.
gable S.- Precipitation, In inches, for period'endlifc at Indicated time, Febru

Station

Santa Clara and Ventura BiTer Baaina Con.

Bouquet Canyon, Bast Spunky Summit

San Ifflis Oblspo Creek Basin

Day

28

I

FeU 27

26

2

3

28

Z

3

1

-

0.04

_

.01

.01

.01

-

.01

.06

Z

0.01

.04

_

-

.04

.01

.05

.01

.20

3

0.04

.20

_

.04

.08

.03

.03

.OS

.02

4

0.07

.20

_

.13

.23

.03

.04

.01

.02

5

6.12

.23

_

.10

.30

.08

.04

.02

.02

6

0.10

.28

_

.07

.25

.28

.03

.01

.02

7

0.10

.15

_

.13

.13

.07

.02

.05

.02

8

0.05

.15

_

.04

.03

.01

-

.26

.01

9

0.06

.33

rtA

.02

.10

.34

.01

-

.30

.02

10

.07

.22

.12

.08

.22

.15

.09

.07

11

.11

.21

.09

.10

.20

.01

.01

.10

.01

12

.34

.07

-

.23

.01

-

.11

.01
Table 6.- Duration and amount of precipitation in excess of indicated rates for 

Station

Tla Juana.Otay. and Sweetwater 

River Baa ms

San Diego 

Santa Ana. San Gabriel, and Los

' Angeles River Basins'

San Gabriel Mountains

Briggs Terrace, Pickena Canyon

Camp Baldy, San Antonio Canyon a/

Chilao, 1 mile north of Newcomb

Ranch

Clear Creek above junction with

Tujunga Creek

Crystal Lake, East Pine Flat

Hennlnger Flats, Mount Wilson

toll road

Hoegee's camp, West Fork of

Santa Anita Creek

Loomls Ranch, near junction of

North and Middle Forks of Alder

Creek

Monrovia Falls, Monrovia Canyon

Mount 01 e as on

Mount Wilson *

Opld's camp, West Fork of San Gabriel River

Pa'eolma flood-control dam

Plckens Canyon

San Antonio guard station a/

San Dlmas Experimental Forest,

Bell-Volfe

San Dimas Experimental Forest,

Tanbark Flats

San Dimas Experimental Forest,

Fern Canyon

San Gabriel, flood-control dam

No. 1

San Gabriel, flood-control dam

No. 2

Altitude 

In 

feet

fyry

O I

2,310

4,320

5,585

3,100

5,740

2,650

2,750

4,300

1,450

5,450

5,850

4,350

1,700

4,250

2,450

1,880

2,700

4,800

1,251

2,335

Duration, in hours, at rates of precipitation, in 

inches per hour, in excess of indicated rates

0.2

4

26

32

19

28

32

28

44

18

38

26

40

32

19

27

28

29

32

34

31

31

0.3

1

22

20

14

19

23

21

36

11

29

17

28

25

15

21

18

19

20

22

21

23

0.4

14

15

13

14

17

15

27

9

20

13

24

19

7

14

16

19

17

16

17

19

0.5

11

15

9

11

13

8

23

6

16

10

18

15

5

8

11

13

13

14

13

15

0.6

8

14

5

10

12

7

17

5

14

7

12

12

1

7

9

9

11

11

10

12

0.7

7

12

3

9

11

5

13

4

10

3

9

12

_

4

7

4

8

9

7

10

0.8

7

9

3

9

7

5

10

2

6

2

9

9

_

3

4

3

6

6

3

8

1.0

2

3

7

3

_

8

1

1

-

7

7

_

2

_

5

3

1

6

1.2

_

3

4

3

_

3

-

-

-

_

5

-

_

2

2

_

2

1.4

_

3

1

3

_

1

-

-

-

_

4

_

-

_

-

-

2

P

0.

0

9.

12.

5.

11.

12.

7.

17.

5.

12.

6.

13.

15.

3.

7.

8.

8.

10.

10.

9.

13

a Partly estimated.
Table 6.- Duration and amount of precipitation in excess of indicated rates for the per

Station

Santa Ana, San Gabriel, and Los

Angeles River Basins Continued

San Gabriel Mountains Continued

San Gabriel River at mouth of canyon

San Gabriel River, East Fork of

Sierra Madre, Hermosa Avenue

Sleepy Hollow Ranch

Upper Halnes Canyon e/

San Bernardlno Mountains

Del Rosa ranger station

Devil Canyon experiment station &/

San Fernando Valley

Van Nuys, city warehouse, Aetna 

and Vesper Streets &/

Verdugo Mountains

Brand Park, 200 feet above tank

Rossmoyne fire area

San Rafael Hills

El Sereno, 4566 Bedllllon Street

Tampico Street

San Gabriel Valley

Azusa, Bonlta Street, west of

Cerritos Avenue

California Institute of Technology

Newmark, Merced Hills, Southern

California Edlaon Co.

Pasadena, Central fire station

Pasadena, Ohio and Euclid Streets

Pasadena, Sunset Reservoir

Pasadena, Washington Street and

Palm Terrace

Altitude

in

feet

BOO

2,500

1,160

3,600

3,450

2,250

2,700

CQC

OfO

1,250

1,500

553

600

545

763

375

052

755

930

1,010

Duration, in hours, at rates of precipitat ion, In

inches per hour, in excess of indicated ra

0.2

26

23

27

24

28

21

23

15

23

22

21

21

21

26

21

22

16

25

24

0.3

17

17

22

15

20

12

18

12

15

13

13

15

13

20

15

20

11

17

18

0.4

13

14

13

15

13

6

14

5

11

9

11

10

5

12

8

11

7

11

13

0.5

6

10

7

10

12

4

11

3

8

8

5

3

4

7

5

6

5

6

9

0.6

5

7

3

9

9

1

7

4

5

3

2

3

5

1

3

4

3

5

0.7

3

4

3

7

8

1

5

2

3

2

-

2

2

1

1

3

1

2

0.8

2

3

1

7

7

1

3

_

-

_

-

1

1

1

1

-

1

2

1.0

_

1

5

3

_

1

_

-

_

-

_

-

_

-

1

1

1.2

_

2

1

_

-

_

-

_

-

_

-

_

-

_

-

tes

1.4

_

_

-

_

-

_

-

_

-

_

-

_

-

_

-

P

0.

6.0

7.0

7.0

9.2

9.1

3;7

7.6

5.5

5.0

4.6

4.1

4.0

6.1

4.2

5.4

3.8

5.6

6.2
CM.no Valley

Claremont, Pomona College Observatory

Etivmnda

Jurupa Basin

Citrus experiment station,

University of California

Santiago Creek Basin

Orange Park Acres

Santiago Dam

Silverado ranger station

Coastal plains

Bel-Air, administration 'building 

Beverly Hills, city hall

Fullerton evaporation station

Griffith Park nursery

Hancock Park, 5801 Wilshire

Boulevard

Laguna Bell

Los Angeles, Sixth and Main Streets

Los Angeles, Ninety-sixth Street

and Central Avenue

Santa Ana, Orange County Flood

Control District office

Signal Hill, city hall

Topanga, Malibu. andCalleguas Creek

Basins

Lechuza, patrol station on Decker

Road

Las Fosas project, McCormick Ranch

Topanga Canyon, 4 miles south of

Topanga Bridge

1,190

1,450

1,075

600

700

1,500

540 

255

90

750

177

140

417

121

130

115

1,530 -

747

15

173

13

15

17

23

18

10

18

14

17

18

13

10

10

24

16

23

12

11248

10

13

125

108

11

13645

146

15

752346

8 93675

10321

111

11

32367125

6 289

1145123

3 157

--

1223134

--

1122

^-

3

----

2

--^-------

2.

1.

I

2.

4.

4.

1.

3.

3.

4.

1.

1

5.

1 

6.

 a Partly estimated.
Table 6.- Duration and amount of precipitation in excess of indicated rates for the pe

Station

Santa Clara and Ventura River Basins

Acton, north branch of Escondido 

Canyon 

Bouquet Canyon, Artesian Springs 

Bouquet Canyon, Cherry Summit 

Bouquet Canyon, Bouquet Canyon road 

near Lincoln Crest 

Bouquet Canyon, at reservoir yard .

Bouquet Canyon, Spunky Summit 

Bouquet Canyon, East Spunky Summit

San Luis Obispo Creek Basin

San Luia Ob Is no

Altitude 

in 

feet

3,075

3,650 

2,975 

3,600

3,000

3,500 

8,725

2RO

Duration, in hours, at rates of precipitation, In 

inches per hour, in excees of indicated rates

0.2

8

16 

13 

14

14

14 

14

s

0.3

5

9 

7 

8

7

7 

5

1

0.4

3 

5 

6

3

5

0.5

2

1

3

2

0.6

-

1

0.7

-

-

0.8

-

'-

1.0

-

-

1.2

-

-

1.4

-

-

0

0.

2.

2 

2.

2n
Table 7.- Maximum rates of precipitation, in inches per hour, for ehorter periods withi

Station

Santa Ana, San Gabriel, and Los Angeles River Basins

San Gabriel Mountains

Briggs Terrace, Pickens Canyon

Camp Baldy, San Antonio Canyon

Chilao, 1 mile north of Newoomb Ranch

Clear Creek, 1.6 miles above junction with Tujunga Creek

Crystal Lake, East Pine Flat '

Henninger Flats, Mount Wilson toll road

Hoegee's camp. West Fork of Santa Anita Creek

Loom! 3 Ranch, near junction of North and Middle Forks

of Alder Creek

Monrovia Falls, Monrovia Canyon

Mount Gleason

Mount Wilson

Opid's camp, West Fork of San Gabriel River

Paooima flood-control dam

Pi ok ens Canyon

San Antonio guard station

San Dimas Experimental Forest, Bell-Volfe

San Dimas Experimental Forest, Tanbark Flats

San Dimas Experimental Forest, Fern Canyon

San Gabriel flood-control dam No. 1

San Gabriel flood-control dam No. 2

San Gabriel River at mouth of canyon

San Gabriel River, East Fork of

Sierra Madre, 575 North Hermosa Avenue

Sleepy Hollow Ranch

Switzer's camp

Upper Haines Canyon

San Bernardino Mountains

Del Rosa ranger station

Devil Canyon experimental station**

Minutes

5

2.28

2.40

1.32

3.84

3.00

3.00

3.60

2.88

2.04

1.80

3.00

4.20

1.68

2.40

2.40

2.40

4.20

2.40

*3.60

2.40

2.16

3.12

2.40

2.76

2.64

3.00

-

10

1.80

2.04

1.32

3.72

2.40

2.40

2.76

1.74

1.80

1.44

3.00

4.14

1.38

1.80

2.10

2.10

3.06

1.56

1.56

#2.52

2.10

1.62

2.40

1.80

1.86

1.92

1.80

-

15

1.60

1.96

1.24

3.08

2.20

2.08

2.16

1.36

1.60

1.28

2.48

3.44

1.28

1.60

1.80

1.60

2.80

1.52

1.40

 2.40

1.64

1.44

1.84

1.68

1.84

1.56

1.40

-

20

1,50

1.92

1.23

2.61

2.10

1.83

1.89

1.20

1.47

1.20

2.07

2.79

1.08

1.50

1.50

1.50

2.40

1.26

*2.07

1.32

1.35

1.50

1.56

1.50

1.47

1.20

-

30

1.28

1.90

1.20

2.44

1.90

1.40

1.82

1.12

1.46

1.02

1.50

2.16

.98

1.40

1.20

1.32

2.04

1.36

1.20

*1.80

1.08

1.30

1.32

1.44

1.26

1.36

1.00

-

1

1.06

1.78

1.00

1.99

1.65

.98

1.50

1.06

-

.97

1.27

1.80

.71

1.00

1.10

1.17

1.40

1.35

1.02

#1.64

.87

1.00

1.16

1.37

1.13

1.23

.90

1.05

1

1

1

1

1

1

1

1

1

1

1

*1

1

1

1

1

*Partly estimated. **Rates for periods 
Table 7.- Maximum rates of precipitation, in inches per hour, for aborter periods within the s

Station

Santa Ana. San Gabriel, and Los Angeles River Basins Con.

San Fernando Valley

ChatSMOrth, Twin Lakes Park fire station 

Van Buys, city warehouse, Aetna and Vesper Streets

Verdugo Mountains

Brand Park 

Rossmoyne fire area

San Rafael Hills

Si Sereno, 4566 Bedilllon Street 

Tanplco Street

San Gabriel Valley

Acusa, Bonita Street, neat of Cerritaa Avenue 

California Institute of Technology 

Remark, Merced Hills, Southern California Edison Co. 

Pasadena, Central fire station 

Pasadena, Ohio and Euclid Streets

Pasadena, Sunset Reservoir 

Pasadena, Washington Street and Pain Terrace

Chino Valley

Claremont, Pomona College Observatory 

Etlwanda

Jurupa Basin

Citrus experiment station, University of California

Santiago Creek Basin

Orange Park Acres 

Santiago Dam 

Sllverado ranger station

Minutes

5

1.92 

1.68

2.28 

4.80

4.08 

2.40

3.00 

2.76 

2.88 

2.40 

1.80

2.40 

2.16

2.16 

1.80

1.20

1.44 

1.08 

1.68

10

1.32 

1.32

1.62 

3.12

2.58 

2.28

2.10 

1.50 

2.34 

2.16 

1.50

1.98 

2.04

1.62 

 1.74

.84

1.20 

.90 

1.32

15

1.12 

1.24

1.32 

2.48

1.96 

1.80

1.60 

1.28 

2.04 

1.76 

1.48

2.08 

1.96

1.32 

1.44

.88

1.12 

.80 

1.16

20

1.02 

1.08

1.23 

2.10

1.59 

1.50

1.32 

1.17 

1.77 

1.53 

1.29

1.86 

1.86

1.05 

1.20

.78

.99 

.78 

1.05

30

0.88 

.96

.98 

1.66

1.14 

1.10

1.10 

1.16 

1.34 

1.18 

.96

1.62 

1.60

.70 

.96

.72

.98 

.72 

.90

1

0.64 

.78

.86 

1.29

.87 

.67

.91 

.91 

.85 

.85 

.79

1.13 

1.13

.53 

.71

.46

.68 

.47 

.61

0.

.

.

.

.

.

.

.

.

.

.

.

.
Coastal plains

Bel-Air, administration building

Beverly Hills, city hall

Fullerton, evaporation station

Griffith Park Nursery, North Commonwealth Avenue

Hancock Park, 5801 Wilshire Boulevard

Laguna Bell

Los Angeles, Sixth and Main Streets

Los Angeles, Ninety sixth Street and Central Avenue

Santa Ana, Orange County Flood Control District office

Signal Hill, city hall

Topanga, Malibu, and Calleguas Creek Basins

Lschuza, patrol station on Decker road

Las Posas project, McCormlck Ranch

Topanga Canyon, 4 miles south of Topanga Bridge

Santa Clara and Venture River Basins

Acton, north branch of Escondido Canyon

Bouquet Canyon, Artesian Springs**

Bouquet Canyon, Cherry Summit**

Bouquet Canyon, at reservoir yard**

Bouquet Canyon, Bouquet Canyon road near Lincoln Crest**

Bouquet Canyon, Spunky Summit**

Bouquet Canyon, East Spunky Summit**

San Luis Obispo Creek Basin

San Luis Obispo

2.28

3.60

2.52

4.56

3.12

3.24

2.52

3.12

1.44

1.32

1.80

1.80

2.88

1.92

-

_

-

1.80

1.92

2.04

1.56

2.88

2.04

1.92

1.98

2.40

1.02

1.14

1.44

.90

2.04

1.20

-

_

-

1.02

1.76

1.68

1.24

2.72

1.60

1.44

1.72

1.80

.88

.92

1.32

.88

2.04

.88

-

_

-

.72

1.50

1.41

1.23

2.04

1.38

1.20

1.50

1.44

.96

.78

1.17

.87

1.83

.72

-

_

-

.57

1.12

1.22

.92

1.48

1.14

.86

1.32

1.04

.82

.64

1.16

.86

1.64

.61

-

_

-

.44

.95

.90

.63

1.00

.92

.58

.90

.66

.59

.46

.79

.67

1.10

.39

.60

.52

.70

.49

.56

.40

.30

 Partly estimated Bates for periods 
FLOODS OF MARCH 1938 IS SOUTHERN CALIFORNIA

Table 8 lists the stations In the several groups and gives for each 

the latitude and longitude, altitude, and recorded rainfall for the total 

storm period and for March 2, the day of heaviest rainfall. General descriptions of the different groups follow.

Group A. Stations at relatively high altitudes on the slopes of the 

second mountain range to the north and east of the zone of heaviest rainfall.

Group B. Stations near or just beyond the first divide and in the 

zone of heaviest rainfall in the San Gabriel and San Bernardlno Mountains.

Group C. Stations on the coastal side of the first divide In a zone 

of heavy though somewhat less average precipitation than observed at the 

stations of group B.

Group D. Stations on the coastal side of the first divide at a 

somewhat lower average altitude and in a zone of somewhat less average 

precipitation than the stations of group C. ,

Group E. Stations situated along the toe of the San Gabriel Mountains, in a zone of less rainfall than the other groups.

Table 8.- Location, altitude, and storm precipitation, for certain groups 

of stations In Santa Ana, San Gabriel, and Los Angeles River Basins

Station and group

Group A

Chilao, 1 mile north of

Newcomb Ranch

Loomis Ranch near junction

of North and Middle Forks

of Alder Creek

Mount Gleason

East Fork of San Gabriel

River

Group B

Camp Baldy, San Antonio

Canyon

Crystal Lake, East Pine Flat

Hoegee's camp, West Fork of

Santa Anita Creek

Opid's camp, West Fork of

San Gabriel River

Group C

Devil Canyon experimental

station

Monrovia Falls, Monrovia

Canyon

Mount Wilson

San Antonio guard station

San Dimas Experimental Forest, Tanbark Flats

Group D

Henninger Flats, Mount Wilson toll road

Pickens Canyon

San Gabriel River at mouth

of canyon

Latitude 

o t n

34 20 31

34 21

34 22 26

34 16 35

34 14 15

34 19 10

34 12 30

34 15 15

34 13 00

34 11 15

34 13 20

34 10 45

34 12 21

34 11 30

34 15 15

34 09 48

Longitude

O | ' II

117 59 30

118 03

118 12 20

117 45 05

117 39 15

117 50 45

118 02 30

118 05 45

117 19 40

117 59 00

118 03 20

117 40 28

II1? 45 34

118 05 15

118 13 00

117 54 17

Altitude 

(feet)

5,585

4,300

5,450

2,500

4,320

5,740

2,750

4,350

2,700

1,450

5,850

2,450

2,700

2,650

4,250 .

800

Precipitation

Mar. 2

8.62

7.96

9.41

9.30

alO.77

13.17

14.87

15.70

a9.37

a7.32

12.58

9.89

11.72

8.91

8.67

7.25

Total

15.76

12.58

16.01

15.75

al9.51

24.45

29.71

27.23

a!5.30

a!6.90

26.25

17.41

21.33

17.44

17.35

14.82

a Incomplete record.
METEOROLOGIC AHD HYJDROLOGIC CONDITIONS

Table 8.- Location, altitude, and storm precipitation, for certain groups 

of stations in Santa Ana, San Gabriel, and Los Angeles River Basins Con.

Station and group

Group E

Azusa, Bonlta Street, west

of Cerritos Avenue

California Institute of

Technology 

Claremont, Pomona College

Observatory

Etiwanda

Nevmark, Merced Hills,

Southern California Edison

Co.

Latitude 

o i n

34 06 24

34 08 16

34 05 52

34 08 15

34 02 45

Longitude o^ , n

117 53 58

118 07 38

117 42 34

117 31 00

118 07 43

Altitude 

(feet)

545

763

1,190

1,450

375

Precipitation

Mar. 2

5.92

7.21

5.45

5.53

5.69

Total

11.77

14.27

9.99

9.96

11.43

The rainfall characteristics at-the stations in these groups are believed to be representative of those of much of the area In which the 

greater part of the flood runoff originated. The data collected at these 

stations have therefore been analyzed in detail. For the three stations 

at which the recording rain-gage record is Incomplete, the missing part 

was computed from additional readings made by observers and from mass 

curves similar to those In figure 9.

Figure 11, based on data in table 6, shows graphically for each group 

of stations the average number of hours of rainfall at rates in excess of 

those indicated, and also the percentage of the total precipitation that 

fell at rates in excess of those indicated. The graphs show the Increase 

In the intensity of rainfall from the group E stations, along the toe of 

the mountains, to the group B stations, in the belt of heaviest precipitation near or just beyond the first divide, and a decrease from the 

group B stations to the group A stations, which are located farther north 

 and some of which are high on the slopes of the secondary divide.

Figure 12 gives, for each group of stations, the average hourly 

rainfall throughout the storm period based on the recording-gage data, 

and figure 13 gives, for each group, the accumulated precipitation In the 

form of mass curves,determined from the data given in figure 12.

All stations show two outstanding periods of intense precipitation, 

separated by an Interval of about 20 hours on March 1, when little or no 

rain fell at any station. In general, little flood runoff occurred during the first major storm period, and the maximum flood runoff In all the 

areas was associated with the precipitation during the second major storm 

period, the third phase of the storm, which occurred March 2. It was the 

rain that fell on this day that was mainly responsible for the Intense 

flood runoff, and the storm characteristics of this third phase have 

therefore been further analyzed.
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

0.1 20 30 40 50 

Percentage of total atona precipitation

70

Figure 11.- Hours of precipitation and percentage of total, In excess of Indicated 

rates, for groups of stations A to B In San Gabriel and San Bernardlno Mountains

and foothill areas.
METEOROLOOIC AND HYDROLOOIC CONDITIONS 86

1.00

Feb. 2-7 Feb. S8 Mar. 1 Mar. 2 Mar. 3 liar. 4

Figure IS.- Average hourly precipitation for groups of stations A to E.
86 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

27 28

February March

..-%,

Figure 13.- Mass curves of accumulated precipitation for groups cf stations A to E.
0.2S

9 Monrovia Falls 11 HeCamp Baldy 

Crystal Lake 

Hoegee 's camp 

Opid's camp

Pi

S

Mt. Oleason 

San Gabriel R. 

(N. Pork)

Tanbark) \» 

13 Devil Canyon 

.'Sta.)

March 2 March 2 

Figure 14.- Time of occurrence of maximum periods of precipitation 
Average precipitation, in inches per h

GROUP E 
METEOROLOQIC AND HTOROLOGIC CONDITIONS 89

Figure 14 gives the time of occurrence of the maximum rate of rainfall at the stations of groups A to E, during the second major storm 

period, for consecutive periods of 15 minutes to 24 hours. The rates of 

precipitation for periods of less than 15 minutes often reflected purely 

local storm conditions not characteristic of any large area. It may be 

observed that, with the exception of group E, each maximum period usually 

occurred within the succeeding longer maximum period. Generally, if a 

shorter maximum period occurred outs-ide the succeeding longer maximum 

period, the rate during the shorter maximum period was only slightly 

higher than the rate for corresponding periods within the longer maximum 

period.

Figure 15 shows the observed rates of precipitation at each station 

in groups A to E for periods ranging from 15 minutes to 24 hours on March 

2. These rates are presented logarithmically, because on this type of 

projection, the tendency for lines to be parallel indicates similar characteristics of rainfall distribution. Considering the scattered locations 

of these stations, the close agreement for groups A and B, in the San Gabriel Mountains, is significant.

In the San Bernardino Mountains there were no recording rain gages 

in the area characterized by the group B type of rainfall. However, the 

record of the 8-inch standard rain gage at Lake Arrowhead (altitude, 

5,000 feet) showed characteristics of precipitation similar to group B. 

On the basis of readings made at approximately 2-hour intervals, this 

record indicated a rate of 1.55 inches per hour for the maximum 2-hour 

period, 1.15 inches per hour for the maximum 6-hour period, 0.98 inch per 

hour for the maximum 8-hour period, and 0.88 inch per hour for the maximum 10-hour period. The station at Big Bear Lake Dam, situated to the 

east of this station, might also be considered in group B, as the record 

from its standard gage showed 1.06 inches per hour for the maximum 5-hour 

period and 1.00 inch per hour for the maximum 10-hour period.

At the bottom of figure 15 the average graph for each of these 

gr"bups of stations is given. The precipitation represented by groups A 

and B ia characterized by a relatively greater prevalence of rainfall at 

higher rates than for the other groups. The rate for the maximum 15- 

minute period was 3.47 times that for the maximum 24-hour period in group 

A and 4.08 times that in group B. The rates for the maximum 1-hour, 

2-hour, 3-hour, and 6-hour periods were 2.68, 2.51, 2.29, and 2.02 times, 

respectively, that for the maximum 24-hour period in group -A. The
90 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

corresponding ratios for group B were 2.84, 2.63, 2.45, and 2.17. It was 

the precipitation of this type that produced the major part of the runoff 

on such streams as the San Gabriel River and San Antonio and Cucamonga 

Creeks.

The average graphs for groups C and D show storm characteristics 

similar to each other but different from those found for groups A and B. 

For periods shorter than 2 hours, the average curves for groups 0 and D 

curve upward more sharply than for groups A and B. The rate for the maximum 15-minute period for group C was 4.32 times the maximum 24-hour rate; 

the corresponding ratio of the maximum 15-minute and 24-hour periods for 

group D was 5.00. For periods of 1 hour, 2 hours, 3 hours, and 6 hours, 

the graph for group C indicated precipitation rates 2.34, 2.10, 2.06, and 

1.78 times the maximum 24-hour rate; for group D, the corresponding 

ratios were 2.76, 2.44, 2.12, and 1.85. On small streams this type of 

precipitation would tend to produce sharp peak discharges.

The average curve for group E on figure 15 is characterized by even 

shorter periods of the heavier rainfall; the maximum rate for a 15-mlnute 

period was 5.96 times that for a 24-hour period. For periods of 1 hour, 

2 hours, 3 hours, and 6 hours, the ratios were 3.07, 2.38, 2.11, and 1.81, 

respectively. The resulting runoff would tend to have even sharper peaks 

than any of the other groups. In many of the smaller canyons at the 

lower altitudes in the vicinity of Pasadena, Monrovia, and La Canada, the 

characteristics of flood flow were determined from this type of rainfall.

Rainfall stations located on the coastal plain and in the Verdugo, 

Santa Monica, and Santa Ana Mountains all showed characteristics very 

similar to those indicated by group E.

The five groups of stations indicate factors that might tend to produce a heavier and more continuous flow for the higher altitudes than for 

the lower altitudes.

The data on intensity for the part of the storm period when the 

rainfall was heaviest have been correlated with observed rates of runoff 

at the reservoirs maintained by the Los Angeles Flood Control District 

and other agencies, and from the relations thus obtained many missing 

records have been filled in, especially for the period of major flow at a 

considerable number of river-measurement stations where, for reasons 

elsewhere explained, observations of stage and discharge were interrupted 

or lost during the flood period.
METEOROLOGIC ASD HYDROLOGIC COHDITIONS 91 

Comparison of rates of Intensity with rates in previous storms

The records from several typical recording rain-gage stations cover 

a period sufficiently long to make possible a comparison between intensities of rainfall during the storm of March 1938 and several previous periods of heavy rains. Burke's report -^ contains a table listing the ' 

rainfall for selected periods of time during the March 1938 storm and 

maxima for previous storms at nine stations in Los Angeles County. This 

interesting table, somewhat modified, is included in this report as table 

9. It indicates that, except at Hoegee's camp, Clear Creek*atatlon, and 

Camp Baldy, the rates of rainldll for periods of 30 minutes or less during 

the 1958 storm were lower than have previously been recorded during the 

relatively short time that the gages have been in operation. According 

to Burke the maximum rate of precipitation for a 5-minute period recor'ded 

during the 1938 storm at Opid's camp (4.30 inches an hour) has been exceeded four times during the 12 years of record. The maximum 5-minute 

rate of 2.52 Inches an hour observed at Los Angeles during this storm has 

been exceeded 17 times during the 38 years of record. For longer periods 

up to 24 hours, the rates of rainfall observed during the 1938 storm approach the previous maximum rates, and at three of the nine locations exceed them. At Opid's camp the rate of 1.80 Inches for the maximum 1-hour 

period recorded on March 2, 1938, has been exceeded only once In the 12- 

year period of record, and the j?ate for the maximum 24-hour period was 

the highest ever observed. At Los Angeles, the rate of 0.90 Inch for the 

maximum 1-hour period during this storm has been exceeded only four times 

in 38 years, and the rate for the maximum 24-hour period has been exceeded 

only once.

Table 9 further shows that at the Los Angeles station of the United 

States Weather Bureau during the 38 years of record prior to March 2, 

1938, the maximum 24-hour rate of precipitation occurred during the New 

Year's storm of 1934. In addition, at each of the other valley-floor and 

foothill stations Van Nuys, Sierra Madre, Claremont, and Hancock Parkthe maximum 24-hour rate occurred during the same storm. It was only in 

the more mountainous sections of the San Gabriel Mountains, at Opid's 

camp, Hoegee's camp, Clear Creek, and Camp Baldy, that the maximum 24- 

hour rate during the 1938 storm exceeded that for the 1934 storm and all 

other storms in the comparatively short periods of record at these stations.

11 Burke, M. P., Flood of March 2, 1938, Los Angeles County Flood 

Control District, May 20, 1938 (processed).
Table 9.- Maximum precipitation during Indicated perlode for period of 

Station

Opld's camp, West Pork of San Gabriel River

Hoegee's camp, West Fork of Santa Anita Creek

Clear Creek, 1.6 miles above Junction with Tujunga 

Creek

Camp Baldy, San Antonio Canyon

Van Nuys, city warehouse, Aetna and Vesper Streets

Sierra Madre, 575 North Hermosa Avenue

Claremont, Pomona College Observatory

Hancock Park, 5801 Wilshire Boulevard

Los Angeles, Sixth and Main Streets

Altitude 

(feet)

4,350

2,750

3,100

4,320

695

1,160

1,190

177

417

Period 

of 

record 

(years)

12

12

10

11

8

11

11

9

38

Storm period

Previous maximum 

March 2, 1938

Previoue maximum 

March 2, 1938

Previoue maximum 

March 2, 1938

Previous maximum 

March 2, 1938

Previous maximum 

March 2, 1938

Previous maximum 

March 2, 1938

Previous maximum 

March 2, 1938

Previous maximum 

March 2, 1938

Previous maximum 

March 2, 1938

5 

minu

a 1.1

.3

c .4

.3

f .3

.5

f .2

.2

5 -2

.1

k .3

.2

m .2

.1

m .3

.2

n .4

.2

a April 4-5, 1926.

b Dec. 31, 1933-Jan. 1, 1934.

c April 29, 1935.

d October 18, 1936.

e April 8, 1935.

f Feb. 11, 1938.

g May 3, 1930.

h Sept. 24-25, 1935.

i Feb. 28 - Mar. 1, 1938.

J Feb. 3, 1931.

k Ja

m O

n Ja

p Fe
METSOROLOOIC AND HYDROLOGIC CONDITIONS 93

During the 38 years of record at Los Angeles the heaviest rainfall 

for periods ranging from 10 minutes to 2 hours occurred on February 18, 

1914, and the rates for 10-minute, 15-minute, 30-minute, 1-hour, and 2- 

hour periods were 2.24, 1.84, 1.73, 1.67, and 1.38 times as high, respectively, as for the 1938 storm. Thus, the March 1938 rainfall at Los Angeles did not at any time exceed in intensity rate, that previously recorded.

Records of short-period rainfall intensities during previous floods 

are not available for the San Bernardino Mountains, and a Comparison is 

therefore impossible. However, a comparison of the observations taken in 

these mountains during the 1938 storm with those taken in the San Gabriel 

Mountains indicates that conditions in the two ranges were in all probability similar. The following comparison is quoted from the record of 

storms since 1884 as compiled by the Bear Valley Mutual Water Company:

In 1891, 32 inches of rain fell in 48 hours at Bear Valley Dam, as 

compared with 21.75 inches In 1916 and 18 inches in March 1938, for a 

similar period. The maximum 24-hour precipitation of 15.06 Inches during 

the March 1938 storm was exceeded only by the February 22-23, 1891, 

storm.

In table 10, there are listed, for 25 selected stations at which 

records are available for periods ranging from 15 to 44 years, the maximum daily precipitation recorded prior to March 1938, the maximum for 

March 1938, and the number of times the latter record has been exceeded. 

The maximum daily rainfall for the March 1938 storm has been exceeded at 

17 of the stations and, on an average, twice at each station. Many of 

these daily records were not obtained from recording rain gages and so 

are not strictly comparable with those so obtained. They seem to indicate, however, that in much of the lower part of the region, the maximum 

daily rainfall during the 1938 storm was not especially extreme. At the 

two stations of the group having the highest altitudes Mount Wilson, 

5,850 feet, and Camp Baldy, San Antonio Canyon, 4,320 feet the maximum 

daily precipitation for the 1938 storm has apparently not been exceeded 

during periods of record of 30 and 17 years, respectively.

Storm movement

Prom the rainfall-runoff studies of the storm of March 1938, it appears that the flood discharge was closely related to the precipitation 

that fell during the second major period of the storm, the 24-hour period 

from about 10 p.m. March 1 to 10 p.m. March 2. For the area of heaviest 

precipitation, where there was a fairly complete coverage by recording 

rain gages, isohyetal maps (pi. 14) have been prepared indicating the
94 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Table 10.- Maximum daily precipitation during March 1938 at selected 

stations compared with maximum previously recorded.

Station

Azusa, Bonita Street,

west of Cerritos Avenue

Claremont, Pomona College

Observatory

Newhall, at Southern Pacific Co. railroad station

Sierra Madre, north end

of Baldwin Avenue

San Dimas, 167 North San

Dimas Avenue

Acton, Just east of summit, Mint Canyon Road

Mount Wilson

Qirard, Brant Ranch

Arroyo Seco Canyon,

chlorine plant

Azusa, Foothill Ranch, 2

miles west of Citrus

Avenue

Claremont, Indian Hill

Road

Santa Anita Canyon ranger

station

San Dimas, 114 East First

Street

Montana Ranch, 3 miles

southwest of Artesia

Sylmar, olive-packing

plant

Camp Baldy, San Antonio

Canyon

Diamond Bar Ranch, Spadra

Office

Olendale, 811 North Olendale Avenue

Pomona, 987 North Weber

Street

Altadena, 575 Sacramento

Street

Covina, Puente Street,

east of high school

San Fernando Lemon Association packing house

Klnneloa Ranch, east side

of Eaton Wash

Lamanda Park

Altadena, Ventura Street

Altitude

545

1,190

1,270

1,110

963

3,250

5,850

892

1,150

615

1,405

1,950

960

47

1,250

4,320

675

653

838

1,125

575

950

1,400

742

1,179

Period 

of 

record 

(years)

44

41

39

39

38

35

30

24

22

22

20

20

20

19

19

17

17

17

16

16

16

15

15

15 '15

Maximum daily 

frecipitation

or to 

March 

1938 

(inches)

7.18

7.82

6.02

7.84

6.98

3.75

11.0

4.55

9.40

9.53

7.77

8.70

5.86

4.00

5.96

10.65

6.62

7.15

5.60

6.91

8.30

7.55

9.20

11.42

5.87

March 

2 or 3 

1938 

( inches )

5.86

5.73

5.38

8.80

6.17

2.82

11.83

5.33

8.63

6.61

5.55

10.64

6.20

3.24

4.35

11.67

4.78

6.90

4.21

8.20

5.13

3.03

8.70

5.70

8.52

Times 

March 

1938 

maximum 

has been 

exceeded

4

2

3

0

2

6

0

0

1

2

3

0

0

2

1

0

1

1

3

0

1

3

1

1

0

Note.- Data based on report of Los Angeles County Flood Control District,

amount of rain that fell during each 2-hour period from 10 p.m. March 1 

to 2 a.m. March 2 and each 1-hour period from 2 a.m. to 10 p.m. March 2. 

In parts of the mountain areas and in San Jacinto River Basin, the isohyetals have been developed from observations at standard gages, the 

total rainfall being distributed on the basis of records at the nearest 

recording gage.
GEOLOGICAL SURVEY WATER SUPPLY PAPER 844 PLATE 14

\

.MOUNTAINS

EXPLANATION 

o Recording rain gage 

 Standard rain gage 

IO O ip 2O Miles

^ BERNAW3.NO

J °° ° " . *. .« ," . " *'N3

'- :: «. ' ' . / ' "

. « e> f " Son Bemordino

___^^ "s~ Loie Ano«l«» ' ~~____t - 

Santo.

3 A.M.- 4 A.M. MAR. 2, 1938 7 A.M.- 8 A.M. MAR. 2, 1938 A.M. 12 M. MAR. 2, 1938 3 P.M. 4 P. M. MAR. 2, 1938 7 P.M.-8 P.M. MAR. 2,1938

10 P.M.-I2 P.M. MAR. I, 1938 4 A.M.- 5 A.M. MAR. 2, 1938 8 A.M.- 9 A.M. MAR. 2, 1938 12 M.- I P.M. MAR. 2, 1938 4 P.M. - 5 P.M. MAR. 2, 1938 8 P.M. 9 P.M. MAR. 2, 1938

12 P.M.-2 A.M. MAR. 2, 1938 5 A.M.- 6A.M. MAR. 2, 1938 9 A.M.- IO A.M. MAR. 2, 1938 I P.M.- 2 P.M. MAR. 2, 1938 5 P.M. 6 P.M. MAR. 2, 1938 9 P.M.-IO P.M. MAR. 2, 1938

2 A.M. - 3 A.M. MAR. 2, 1938 6 A.M.- 7 A.M. MAR. 2, 1938 IO A.M.-II A.M. MAR. 2, 1938 2 P.M.- 3 P.M. MAR. 2, 1938 6 P.M.-7 P.M. MAR. 2, 1938

PRECIPITATION IN PAilT OF SOUTHERN CALIFORNIA FOR INDICATED INTERVALS OF THE MAXIMUM 24-HOUR PERIOD, 10 P.M. MARCH 1 TO 10 P.M. MARCH 2, 1938 " s GOVERNMENT PRINTING OFFICE : 1942 o- 454720

I 

I
METEOROLOOIC AND HYDROLOGIC CONDITIONS 95

The general eastward movement of the storm and the tendency for the 

heaviest rainfall to occur in the mountains is clearly indicated by the 

series of rainfall maps shown on plate 14. With the exception of a 

period from about 7 to 9 a.m. March 2, when rain fell at a rate of I inch 

an hour on the coastal plain, the area over which a rate was 1 inch or 

more an hour lies chiefly in the San Gabriel and San Bernardino Mountains. 

Prom about noon until 2 p.m. March 2 rain was falling at the highest intensity and over the largest area In the San Gabriel and San Bernardino 

Mountains. Following this period there was a general eastward movement 

of the storm, and by 7 p.m. the rainfall rate had dropped to 0.1 inch an 

hour in the central part of the area, and it was only in the extreme 

eastern part that the rate exceeded 1 inch an hour. By 9 p.m. the rate 

at all stations was reduced to less than 1 inch an hour.

Antecedent precipitation

In southern California the greater part of the annual precipitation 

occurs during a comparatively short rainy season that is followed by a 

long dry season, during which there is a gradual draining out of the 

ground water and a loss of moisture through evaporation and transpiration. As the rainy season progresses the absorptive capacity of the ground 

tends gradually to be fully utilized, and the magnitude of the runoff following any storm therefore depends to a large extent on the time of occurrence of the storm within the rainy season and the amount of antecedent precipitation. Table 11 gives, for each of eight typical stations, 

the total precipitation and departure from normal for the periods July 1, 

1937, to January 31, 1938, and February 1-25, 1938, and the total departure from normal for the period July 1, 1937, to February 25, 1938. The 

selected stations are distributed over the area from San Diego on the 

south to San Luis Obispo on the north. The stations in the middle part 

of the table represent the area of heaviest rainfall during the storm of 

February 27 to March 4, 1938. The remaining stations are' situated around 

the margin of the storm area.

From table 11 It is evident that the seasonal precipitation prior to 

February 1, 1938, was below normal except at Pattiway and Santa Maria. On 

the other hand, the precipitation for the first 25 days in February was 

so greatly above normal as to more than make up for the deficiency prior 

to February 1. Squirrel Inn and Mount Wilson, located near one of the 

storm centers, had excesses of 9.67 and 8.32 inches above normal, respectively, during the first 25 days in February, and similar trends of less
96 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Table 11.- Precipitation and departure from normal, In inches, at typical 

stations, for periods from July 1, 1937, to Feb. 25, 1938

Station

San Diego

Cuyamaca

Santa Ana

Riverside

San Bernardino

Squirrel Inn

Mount Wilson

San Fernando

Los Angeles

Oxnard

Ojal

Pattlway

Santa Barbara

Santa Maria

San Luls Oblspo

Precipitation 

July 1, 1937 

to 

Jan. 31, 1938

Total

2.13

10.16

4.30

3.01

5.58

14.84

11. £7

5.41

5.18

5.93

7.40

4.77

6.55

8.03

11.01

Departure

-3.25

-8.35

-2.40

-2.52

-2.11

-4.06

-1.92

-2.09

-2.63

-.86

-2.79

+ .27

-3.09

+ .88

-.32

Precipitation 

Feb. 1-25, 1938

Total

2.11

8.39

4.95

1.83

4.02

17.03

14.02

6.82

5.49

3.06

9.60

2.45

7.34

6.23

11.68

Departure

+0.30

+1.77

+2.56

-.08

+1.31

+9.67

+8.32

+3.75

+2.75

+1.10

+5.89

+ .42

+3.88

+3.77

+7.97

Departure 

from normal 

July 1, 1937 

to 

Feb. 25, 1938

-2.95

-6.58

+ .16

-2.60

-.80 

+5.61

+6.40

+1.66

+ .12

+ .24

+3.10

+ .69

+ .79

+4.65

+7.65

magnitude are shown for all stations except Riverside.

The effect of this generally heavy precipitation prior to the March 

storm was to increase the soil moisture, to lessen the capacity for storage afforded by surface detention, and in much of the mountain area to 

replenish, in part at least, the ground-water storage. These conditions 

tended to increase the direct runoff resulting from the storm of February 

27 to March 4 to an amount above what it would have been if there had 

been less rain in the period Just prior to the storm.

The influence of antecedent precipitation is discussed further in 

the section entitled "Rainfall, runoff, and retention".

Snow

Records of snowfall prior to and during the storm of March 1938 are 

few and fragmentary. At Bear Valley Dam (altitude, 6,800 feet), on the 

headwaters of Bear Creek, a tributary of the Santa Ana River in the San 

Bernardino Mountains, the following observations were made by the president and general manager of the Bear Valley Mutual Water Co.:

In this 1938 storm, we estimate that the average depth of snow at 

the beginning of the storm on the watershed was 18 inches. With 9 inches 

added at the close of the storm, the appearance of the 'snow cover in the 

valley was very much the same at the end as at the beginning. At no time 

did the snow lose its structure or slush down. The rain seemed to pass 

right through it and come running out under the snow. Temperatures early 

in the storm of March 2 were 36° to 38°, but about 4 a.m. on March 3 the 

temperature dropped to 28°, the precipitation changed to sleet and snow, 

and the runoff decreased immediately.

12 Pendergast, J. J., Memorandum on storms, 1884-1938.
METEOROLOGIC AND HYDROLOGIC CONDITIONS 97

At the Big Pines station of the Los Angeles County Flood Control 

District (altitude, 6,860 feet), on the desert side of the San Gabriel 

Mountains, In the Great Basin, 19 inches of snow was reported on the 

ground on February 27, 7 inches fell during the storm, and 23 inches remained on March 4. Table Mountain station (altitude, 7,500 feet), a 

short distance from Big Pines station, recorded 32 inches of snow on the 

ground on February 27, a fall of 8 inches during the storm, and 27 inches 

remaining March 4. At a few other stations the records are not so complete, owing to infrequent observations.

At Kelly's Kamp (altitude, 8,300 feet), in the San Antonio Creek 

Basin, 72 inches of snow was reported on the ground on February 28 and 

60 inches on March 9, but of the 32 inches of storm precipitation, only a 

trace fell in the form of snow. Mount Gleason station (altitude, 5,450 

feet), on the headwaters of Pacoima Creek, recorded 3 inches.of snow on 

the ground on February 13, 2 inches on February 28, and none on March 15. 

At Opid's camp (altitude, 4,350 feet), in the basin of West Fork of San 

Gabriel River, in the San Gabriel Mountains, there was no snow on the 

ground on February 28, 1 inch on March 3 and half an inch on March 4. 

These stations represent most of the areas in southern California in 

which snow is an important factor in seasonal runoff.

These fragmentary observations in the San Bernardino and San Gabriel 

Mountains indicate the probable absence of snow at the beginning of the 

storm period at an altitude of about 5,000 feet or less. Above 6,000 

feet there was a snow cover of considerable depth, with a maximum of more 

than 70 inches in some areas at an altitude of 8,000 feet and above. It 

appears that at the higher altitudes some snow accumulated during the 

storm, and that at the lower altitudes there was no material depletion in 

snow cover. At stations located at an altitude of more than 6,000 feet, 

some of the precipitation during the later part of the storm occurred as 

sleet and snow. In general, the snowmelt is believed to have contributed 

but little to the flood runoff, and in the headwater areas the flood runoff may have been less than it would otherwise have been because some of 

the precipitation occurred as snow, which remained on the ground after 

the storm. Roughly, 30 percent of the area of the basins above the 

stream-measurement stations in the San Gabriel and San Bernardino Mountains is above 6,000 feet, and 5 percent is above 8,000 feet.

In Ban Diego, Ventura, and Santa Barbara Counties the snowfall is 

usually light and seldom remains long on the ground. The snowfall in 

these counties from February 27 to March 4, 1938, was negligible.
98 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

BASIC DISCHARGE RECORDS

During a major flood It is extremely difficult, If not Impossible, 

to obtain continuous accurate records of discharge of the streams In 

southern California. In determining discharge at a stream-measurement 

station, current-meter measurements are made to establish a rating curve 

that will show the discharge for any given stage at a given time. Ordinarily the rating curve can be defined by measurements for the usual 

range of stage, but its definition is more difficult for unusually high 

stages, and Increasingly difficult for flood stages so high as to be of 

rare occurrence, when conditions for obtaining measurements are most unfavorable .

Complete definition of the rating curve to the highest peak can be 

obtained only by an adequate number of timely measurements and a record 

of channel conditions during the flood. In southern California, this 

ideal is difficult to attain owing to the fact that it Is practically impossible to make current-meter measurements during the higher flood 

stages. The streams have flashy floods with excessively high velocities 

and usually move large quantities of debris and suspended material. Their 

flood crests frequently occur almost simultaneously throughout the area, 

and often during the night. The field engineer is further handicapped 

during flood periods by washed-out or obstructed routes of travel and at 

times by damage to bridges or cableways from which discharge measurements 

are made.

For many streams in both the mountain and valley areas, the continual shifting of their channels owing to scour, fill, or bank cutting make 

it Impossible to develop a stage-discharge relation even If it is possible 

to obtain a large number of measurements. On the Los Angeles River at 

Los Angeles, 44 current-meter measurements made in the period February 28 

to March 5 showed that no stage-discharge relation could be defined. For 

this reason many of the gage-height records in the main flood area were 

of little value as an indication of the magnitude of the flood runoff.

There were, however, within the flood area a number of flood-control 

reservoirs from the records of whose contents it was possible to compute 

fairly satisfactory records of runoff for the flood period. Similar records were available for certain reservoirs that are maintained for purposes other than flood control. For a. small number of other streams, 

also, the records of discharge through the flood rise are believed to be
BASIC DISCHARGE RECORDS 99

reliable with respect to rates of flow for short periods. The aforementioned records are presented herein as "basic discharge records" and are 

analyzed In relation to rainfall rates and other pertinent factors in order to develop relations which are of general Interest and which may be 

used in interpreting the often meager data obtainable at streammeasurement stations.

In measuring the outflow from these reservoirs, the ratings for the1 

valves and spillways are based mainly on current-meter measurements, although a few are based on model ratings. The operation of the release 

valves in the dams made It necessary to compute the inflow and outflow 

from the reservoir for intervals of time between readings of the valve 

openings. This opening and closing of the valves necessarily affects the 

record of stage in the reservoir and makes difficult the accurate determination of inflow data for very short intervals of time. At some reservoirs the operation of these valves resulted in so much drawdown at 

the water-stage recorder that the record was not a correct index of inflow. For such periods observations made on staff gages, which are not 

affected by drawdown, were used as a true index of reservoir stages. 

During the periods of greatest disciiarge the staff gages were read frequently.

Shortly after the floods the flood-control reservoirs were resurveyed by the California Institute of Technology, the Los Angeles County 

Flood Control District, and the United States Soil Conservation Service, 

and new capacity tables were prepared. In determining the inflow to the 

reservoirs the older capacity tables were used prior to the time of the 

maximum discharge and the new capacity tables subsequently.

The estimated storage, which is added to or subtracted from the 

spillway discharge and valve release in order to determine the inflow, 

was based on the area of the water surface at the time of observation, 

the rate of change In area,-and the rate of change in the altitude of the 

water surfaces. The surveys made after the storm period indicate that 

the area of the water surface for each gage height had been decreased 

somewhat by debris deposition, with the higher gage heights showing the 

least change in area. The shift of capacity tables at the time of the 

maximum discharge has the tendency to Increase the computed inflow on the 

rising stages during the periods of greatest runoff and to decrease to a 

much slighter degree, however, the computed Inflow on the falling stages.
100 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Most of these reservoirs were practically full prior to the periods 

of maximum discharge, so there was little fluctuation In the area and altitude of their water surfaces during these periods. The rather small 

capacity of the reservoirs found In these steep, narrow canyons tends to 

reduce further the Influence of change In storage on the Inflow computations. It Is under these conditions that the change In storage factors 

would have the minimum Influence on the Inflow computations.

The computed Inflow to these reservoirs includes not only the water 

but the debris that was carried with it and deposited in the reservoirs. 

As incoming debris entered the upper end of a reservoir, it caused the 

displacement of water at a rate and in a volume equivalent to its own. 

The section on debris (pp. 372-376) discusses the deposition of debris in 

the reservoirs. Theoretically, debris movement varies with the fifth or 

sixth power of the velocity. Since the highest velocity is associated 

with the greatest discharge, It might be assumed that the greatest Inflow 

of debris would also be associated with the greatest discharge. Available information indicates that streams tend to carry more debris on rising than on falling stages. For this reason it may be assumed^that most 

of the inflow of debris occurred during the greater discharges.

Table 28 (p. 374) shows, in acre-feet per square mile of drainage 

area, the debris deposited in each of 13 reservoirs, as determined from 

surveys before and after the flood, and the inflow to each for the maximum 24 hours. In the aggregate, the debris inflow is computed to be between 8 and 9 percent of the maximum 24-hour Inflow, with the percentages 

for individual reservoirs ranging generally from 5 to 15. Probably the 

debris was associated mostly with the rising side of the flood hydrograph 

and with perhaps less than half of the volume of flow in the maximum 24 

hours, thus apparently increasing the content of debris considerably 

above the percentages indicated. The significance of this complicating 

factor in relation to the computed inflow and, the correlation of rainfall 

and runoff rates must be kept in mind.

The complicating factor of debris enters into the measurement of the 

flood flow of all the mountain streams of southern California, as is 

pointed out in other places in this report. The reservoir records permitted a more reliable determination of the flow including the debris 

than was possible at any of the gaging stations. The records are especially valuable in furnishing information as to the volume of debris
BASIC DISCHARGE RECORDS 101

borne by the flood waters of natural streams, this being a subject on 

which reliable data are very meager.

The inflow and outflow for the flood-control reservoirs during the 

main part of the storm period and the peak discharges have been computed 

by the Geological Survey from data furnished by the Los Angeles County 

Flood Control District, but these data were not complete at the time this 

report was prepared. Owing to differences in interpretation of the basic 

data., some of the results differ by relatively small amounts from those 

reported by the flood-control District. 13 The records for Morris Reservoir were computed and furnished by the City of Pasadena Water Department. 

The records for Santiago Creek Reservoir were computed and furnished by 

the Corps of Engineers and the Orange County Flood Control District.

Records were furnished by the United States Forest Service for two 

basins in Fern Canyon, designated Watersheds Nos. 2 and 3, having drainage areas of 0.063 and 0.084 square mile, respectively. No runoff records were obtained from the Watershed No. 1 because of damage to the 

measuring equipment. These watersheds are small, contiguous basins lying 

along the eastern divide of the San Dimas Creek drainage area, within the 

San Dimas Experimental Forest. (See pi. 15.) They have an average altitude of about 5,000 feet and an average slope of about 65 percent. The 

soil mantle varies in depth from less than 1 foot to more than 2 feet, 

with an average of about 1 foot. At the time of the flood of March 1938, 

each basin had a fairly heavy and uniform chaparral cover. At the lower 

end of each basin is a concrete dam, founded on bedrock, above which is a 

concrete-lined reservoir with a capacity of 10,000 cubic feet, built to 

trap the erosional debris. The runoff of these basins was measured by a 

modified 3-foot Parshall flume and a 90° V-notch weir.

The United States Forest Service has also made available basic records on Wolfskill Creek and West Fork of San Dimas Creek, in the San 

Dimas Creek Basin. In addition, the United States Soil Conservation Service maintained several broadcrested-weir gaging stations on Honda Barranca in the Los Posas area, for which records are presented-*

In general there are given for each reservoir a description of the 

station, a table of mean daily and monthly inflow to the reservoir

13 Los Angeles County Flood Control District, Biennial report on 

hydrologic data, seasons 1936-37 and 1937-38, June 30, 1939.
102 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

throughout the 3-month period February to April 1938, a table of hourly 

or blhourly inflow for the period February 27 to March 10, 1938, and corresponding tablea of outflow. The preaentation of the data haa followed 

a uniform plan aa far aa practicable.

The atation deacription givea, in the firat paragraph, the location 

of the reaervoir and the altitude of the stream bed at the dam. A aecond 

paragraph givea characteriatica of the drainage area upatream from the 

dam. Each drainage area aa measured on the moat recent topographic maps, 

and ita average altitude was determined by planimeter. It waa then divided into small areaa, ranging from 1,000 feet to 1 mile aquare each, 

and the average alope of each waa estimated. The average of these estimates waa taken aa the average alope for the entire area. The average 

alope of the main stream channel was obtained by dividing the difference 

between the maximum and minimum altitudea of the channel by the length of 

the channel aa acaled from the topographic maps. The next paragraph, relating to the gage-height record, gives the method of determining the 

stage during the flood. In a fourth paragraph ia given the method of 

computing the diacharge. Thia ia followed by a paragraph giving the 

maximum diacharge and the time of ita occurrence. The method of estimating the maximum diacharge ia diacuaaed later. The aixth and laat paragraph, under the heading "Remarka", begina with a atatement concerning 

the reliability of the record; it then givea the altitude of the spillway, the area of the reaervoir at the apillway, the capacity of- the reaervoir before and after the flooda, a atatement concerning atorage or 

diversion upatream from the reaeryoir, and other miacellaneoua information. Similar descriptiona for atationa other than thoae at reaervoira 

were alao furnished.

Following each deacription, if the recorda are available, ia a table 

showing the mean daily inflow in aecond-feet, and the monthly inflow in 

acre-feet for the period February 1, 1938, to April 30, 1938. Thia covera the actual floMOd.,period and aufficient time before and after it to 

eatabliah the relationa of flood diachargea to the prevalent diacharges 

and to give a general perapective of the March flood. The table of inflow at indicated timea waa obtained from inflow hydrographs developed on 

the baaia of the gage-height record from the water-atage recorder on the 

reaervoir, aupplemented by ataff readings and recorda of valve operation. 

The table of outflow from each reservoir ia presented immediately following the table of inflow.
GEOLOGICAL SURVEY WATER-SUPPLY PA PEE 844 PLATE 15

FERN CANYON WATERSHEDS NOS. 1, 2, AND 3.

Vegetation unburned for past 50 years. 47 rain gages are located on contour trails at altitudes of 4,700. 4,Q50. and 5,200 feet on total area of 128 acres. Courtesy of U. S. Forest

Service.

BASIC DISCHARGE RECORDS 103

The outflow from the reservoirs was governed mainly by the opening 

and closing of valves, resulting in a steplike hydrograph. Daily discharges were computed from this steplike hydrograph, but in computing the 

outflow at indicated times, a smoothed hydrograph was used; the total 

discharge for any hour is approximately the same computed from either hydrograph.

Hydrographs of inflow into five of the flood-control reservoirs, 

namely, those on Tujunga Creek, West Fork of San Gabriel River, Santa 

Anita Creek, Eaton Creek, and Live Oak Creek, are shown on figure 16. 

The drainage areas of these streams represent a wide variety of basin 

characteristics, with that of Eaton Creek having the steepest slope and 

that of Live Oak Creek the gentlest. The West Pork of San Gabriel River 

had the greatest runoff to the square mile, however, and Live Oak Creek 

the least.

454720 O - 42 - 8
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

g 1,500

Feb. 28 Mar. 1 Mar. 2 Mar. 3 

Figure 16.- Graphs of discharge Into various reservoirs in southern California, March 1938.
BASIC DISCHARGE RECORDS 105

Santa Ana River Basin

Santiago Creek at Santiago Reservoir, near Villa Park, Calif.

Location.- Water-stage recorder, lat. 33°47'0011 , long. 117° 43 '35" , In Lomas de Santiago 

grant, 2 miles east of Orange County Park, and 5 miles east of Villa Park, Orange 

County. Altitude of stream bed, 680 feet.

Drainage area.- Area, 62.5 square miles. Average altitude, 2,120 feet. Maximum altltude, 5,680 feet. Average slope, 45 percent. Length of main stream channel, 13.0 

miles. Average slope of main stream channel, 7.3 percent.

Page-height record.- Water-stage recorder graph.

Discharge record.- Computed from record of stage, stage -capacity tables, and spillway 

rating curve.

Maxima.- 1938: Inflow, 9,850 second-feet 5 p.m. Mar. 2.

Outflow, 5,670 second-feet 9:30 p.m. Mar. 2.

Remarks . - Records good. Capacity at spillway level, 25,000 acre-feet. Reservoir operated by Irvlne Co. and Serrano and Carpenter Irrigation Districts. Records furnished by Corps of Engineers, U. S. Army, and Orange County Flood Control District 

through M. N. Thompson, chief engineer.

Mean daily Inflow, In second-feet, 1938

Feb. 28 

Mar. 1

... 243

... 586

2 ....... 4,200

3 ....... 2,430

4 ....... 1,150

5 ....... 803

Mar. 659

575

549

529

501

469

Inflow Feb. 28 to Mar. 11, in acre-feet. .25,180 

Inflow, in second-feet, at Indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

I

2

3

4

5

6

7

8

9

10

11

M

Feb. 26

90

92

92

92

104

150

203

189

184

190

211

249

370

660

1,050

1,420

Mar. 1

1,600

1,700

1,410

1,000

867

760

655

570

550

512

405

342

321

313

308

299

270

241

224

211

211

220

232

248

Mar. 2

328

430

500

675

920

1,040

1,280

1,750

2,700

3,060

3,600

4,130

5,300

6,950

7,800

8,650

9,850

9,100

7,800

6,900

5,950

5,270

4,700

4,170

Mar. 3

3,800

3,400

3,130

3,040

2,980

2,900

2,840

2,800

2,690

2,600

2,470

2,330

2,220

2,120

2,060

2,000

1,930

1,870

1,800

1,710

1,650

1,600

1,550

1,500

Mar. 4

1,410

1,350

1,300

1,240

1,190

1,130

1,080

1,040

1,010

980

940

910

Mar. 5

885

835

790

760

740

710

Mar. 6

700

680

660

640

620

600

Mar. 7

593

587

580

560

555

550

Mar. 8

555

560

555

545

540

530

Mar. 9

530

530

530

530

530

525

Mar. 10

520

505

500

495

485

475

Mean dally outflow, in second-feet, 1938

Feb. 28 ....... 0

Mar. 1 ....... 0

2 ....... 1,700

3 ....... 3,180

4 ....... 1,410

Mar. 6 

7

10

11

703

600

557

532

512

476

Outflow Feb. 28 to Mar. 11, In acre-feet. 20,960
106 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Outflow, In second-feet, at Indicated tine, 1938

HP.

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 28

0

0

Mar. 1

0

0

Mar. 2

0

0

330

1,070

2,030

3,160

4,270

5,010

5,480

5,630

5,630

5,520

5,310

Mar. 3

5,060

4,770

4,460

4,180

3,950

3,790

3,650

3,520

3,390

3,270

3,140

3,020

2,900

2,780

2,670

2,570

2,480

2,390

2,310

2,220

2,120

2,040

1,980

1,920

Mar. 4

1,850

1,800

1,740

1,700

1,650

1,600

1,540

1,510

1,470

1,440

1,410

1,380

1,340

1,300

1,260

1,240

1,210

1,190

1,170

1,160

1,120

1,100

1,080

1,060

Mar. 5

1,030

990

960

940

910

890

860

840

810

810

790

770

Mar. 6

760

745

740

728

710

705

685

680

670

660

646

635

Mar. 7

628

620

600

580

574

568

Mar. 8

560

560

560

560

550

542

Mar. 9

536

530

530

530

530

530

Mar. 10

520

520

512

504

504

494

Supplemental record.- Mar. 2, 9t30 p.m. 5,670 sec.-ft.

San Qabrlel River Basin

San Qabrlel River at flood-control reservoir No. 1, near Azusa, Calif.

Location.- Staff gage, lat. 34°12'15B , long. 117°51'20", In MEi sec. 6, T. IN., 

R. 9V., 6 miles northeast of Azusa. Altitude of stream bed, about 1,200 feet.

Drainage area.- Area, 202 square miles. Average altitude, 4,500 feet. Maximum altltude, 10,080 feet. Average slope, 49 percent. Length of main stream channel, 24*5 

miles. Average slope of main stream ohannsl, 6.9 percent.

Page-height record,- Staff gage read daily at 8 a.m., more frequently during storm

peri and at .about 4-minute intervals 3-7 p.m. Mar. 2.

Discharge record.- Computed from record of stage, spillway rating table, valve rating 

curves, valve-operation record, and changes In storage based on record of stage and 

stage-capacity tables: stage-capacity table based on survey of 1937 used to tine of 

peak stage of Mar. 2 (7:30 p.m.), table based on survey of October 1938 used 

thereafter.

Maxima.- 1938s Inflow, 90,000 second-feet 4 p.m. Mar. 2. 

Outflow, 56,700 second-feet 7:30 p.m. Mar. 2.

Remarks.- Records good. Altitude of spillway, 1,453 feet. Area at spillway level, 

523 acres (Oct. 1938). Capacity at spillway level before storm of Mar. 2, 53,334 

acre-feet; after storm, 47,191 acre-feet. Partial regulation at flood-control dam 

No. 2 on West Fork of San Gabriel River, 10 miles upstream. Outflow goes directly 

into Morris Reservoir. Basic data Feb. 27 to Mar. 11 and entire record for rest of 

February, March, and April furnished by Los Angeles County Flood Control District, 

through E. E. Hedger, chief engineer.

Mean dally Inflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

215

129

510

749

420

286

228

206

291

367

Mar.

5,290

31,100

15,700

7,790

4,570

3,730

3,390

3,100

3,480

2,080

Apr.

525

763

699

688

773

747

700

632

648

692

Day

11

12

13

14

15

16

17

18

19

20

Feb.

963

903

554

448

378

329

300

294

312

269

Mar.

1/220

4,190

3,400

2,550

2,040

1,470

1,270

1,220

1,170

1,100

Apr.

667

719

593

554

516

488

474

475

496

506

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

253

249

236

239

240

233

419

2,850

25,530

Mar.

1,260

1,330

1,280

1,21.0

1,190

1,110

1,070

1,050

940

854

801

222,100

Apr.

488

476

432

505

511

436

398

390

405

387

561

33,390
BASIC DISCHARGE RECORDS 107

Inflow, in second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

H

1 

2

3

4

5

6

7

8

9

10

11

12

2

4

6

8

10

H

2

4

6

8

10

M

February 27

242

238

236

233

232

246

262

280

295

310

330

352

375 

405

443

489

535

575

612

647

685

730

775

805

March 5

5,020

4,900

4,810

4,700

4,610

4,480

4,320

4,200

4,310

4,380

4,360

4,300

February 28

833

855

865

892

945

1,070

1,530

2,160

2,510

2,900

3,200

3,360

3,540 

3,800

3,940

3,680

3,490

3,330

3,300

3,380

3,450

3,700

6,800

9,100

March 6

4,270

4,220

4,150

4,090

3,570

2,840

2,810

3,700

3,760

3,740

3,690

3,630

March 1

10,600

9,530

8,960

8,570

8,320

8,000

6,800

5,320

4,930

4,700

4,420

4,120

3,910 

3,780

3,600

3,360

2,890

3,040

3,460

3,300

3,140

3,060

3,000

3,010

March 7

3,610

3,590

3,550

3,500

3,400

3,350

3,320

3,290

3,260

3,220

3,210

3,200

March 2

3,070

3,160

3,300

3,200

3,120

3,170

7,600

9,200

10,700

15,500

20,200

27,600

39,000 

57,300

69,500

90,000

81,000

72,000

59,500

48,300

40,800

35,800

31,300

29,000

March 8

3,180

3,170

3,160

3,120

2,710

2,110

2,420

2,630

3,260

3,900

3,980

3,950

March 3

26,900

24,000

19,200

18,800

20,700

19,900

18,800

17,700

16,600

15,900

15,100

14,500

13,700 

13,100

12,800

12,500

12,000

11,700

11,400

11,100

10,800

10,600

10,300

10,000

March 9

3,950

3,980

4,000

4,010

3,990

3,920

3,330

2,790

2,200

2,700

3,250

3,290

March 4

9,760

9,300

8,800

8,540

8,320

8,000

7,730

7,550

6,900

5,680

5,390

5,200

March 10

3,280

3,250

3,220

3,190

2,370

1,600

1,280

1,220

1,100

1,080

1,140

1,210

Mean daily outflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

a

9

10

Feb.

133

177

181

147

162

191

177

204

199

239

Mar.

0

11,800

16,700

8,080

4,640

3,790

3,420

3,100

3,540

2,300

Apr.

1,150

2,820

2,770

2,700

2,640

2,560

2,490

2,400

2,300

2,190

Day

11

12

13

14

15

16

17

18

19

20

Feb.

285

309

183

137

288

321

304

282

538

524

Mar.

1,410

3,790

3,490

2,590

2,140

1,520

1,350

1,330

1,330

1,320

Apr.

1,420

499

501

504

504

504

504

503

503

503

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

528

532

507

504

502

478

489

291

315

17,480

Mar.

1,140

1,380

1,380

1,380

1,380

1,370

1,370

1,370

1,360

1,360

932

2,970

182,600

Apr.

503

502

501

501

167

1

1

1

1

1

1,070

63,760

Outflow, in second-foet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

0

10

11

H

1

2

3

4

5

6

7

a

9

10

11

M

February 27

490

490

490

490

489

488

487

486

487

488

490

492

February 28

494

496

498

500

510

520

527

0

0

0

0

0

0

March I

0

0

0

0

0

0

0

0

0

0

0

0

March 2

u

0

0

0

0

0

0

0

0

0

0

36,700

56,400

54,400

47,000

40,600

35,400

31,600

March 3

29,200

26,600

24,400

22,800

21,500

20,500

19,700

18,800

17,700

16,800

15,900

15,200

14,500

13,800

13,300

13,000

12,600

12,100

13,800

11,500

11,200

11,000

10,700

10,300

March 4

10,200

10,000

9,800

9,600

9,300

9,100

8,900

8,700

8,600

8,500

8,350

8,200

8,000

7,940

7,860

7,740

7,600

7,400

6,830

6,180

5,970

5,700

5,500

5,400
108 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Outflow, In second-feet, at indicated time, 1958 Continued

Hour

2

4

6

8

10

N

2

4

6

8

10

M

March 5

5,180

5,000

4,850

4,780

4,680

4,580

4,420

4,300

4,270

4,360

4,360

4,360

March 6

4,310

4,270

4,220

4,190

3,960

3,320

2,960

3,200

3,640

3,720

3,760

3,680

March 7

3,620

3,600

3,550

3,520

3,440

3,400

3,360

3,320

3,280

3,230

3,210

3,200

March 8

3,190

3,160

3,160

3,180

3,020

2,600

2,470

3,100

2,920

3,430

3,820

3,940

March 9

3,960

3,980

3,980

3,980

3,980

3,980

3,820

3,250

2,860

2,540

2,930

3,150

March 10

3,250

3,250

3,250

3,220

3,050

2,320

1,820

1,540

1,340

1,220

1,180

1,160

Supplemental record.- Mar. 2, 7(30 p.m., 5ff,700 sec.-ft.

San Gabriel River at Morris Reservoir, near Azusa, Calif.

Location.- Water-stage recorder, lat. 34°10'25n , long. 117°52'50", In Nfii sec. 13, T. 1 

N., R. 10 W., 3j miles northeast of Azusa. Altitude of stream bed, about 950 feet.

Drainage area.- Area, 211 square miles. Average altitude, 4,480 feet. Maximum altltude, 10,080 feet. Average slope, 49 percent. Length of main stream channel, 27.5 

miles. Average slope of main stream channel, 6.3 percent.

Page-height record.- Water-stage recorder graph and frequent staff-gage readings.

Discharge record.- Inflow computed from outflow, records of evaporation and diversion, 

and changes in storage, based on reoord of stage and stage-capacity tables. Outflow 

computed from reoord of stage, spillway rating curve, valve rating curve, and gate 

and valve operation record.

Maxima.- 1938: Inflow, 66,200 second-feet 7:25 p.m. Mar. 2.

Outflow, 65,700 second-feet 7:05 p.m. Mar. 2. 

1894-1937: Discharge, 40,000 second-feet Jan. 18, 1916.

Remarks.- Records good. Altitude of spillway, 1,152 feet; top of gates, 1,170 feet. 

Area at spillway level, 414 acres. Capacity before storm of Mar. 2, at spillway 

level, 31,700 acre-feet and at top of gates, 38,690 acre-feet} capacity after storm, 

30,180 and 37,170 acre-feet, respectively. Inflow partially regulated by floodcontrol reservoir No. 1, 3 miles upstream, and flocd-control reservoir No. 2, 13 

miles upstream on West Fork of San Gabriel River. Records of Inflow and records of 

outflow for Feb. 22 to Apr. 30 furnished by City of Pasadena Water Department.

Mean dally Inflow, In second-feet, 1938

.. 235 Feb. 25 ....... 517

.. 288 26 ....... 507

..575 27 ....... 535

.. 552 28 ....... 567

.. 558 Mar. 1 ....... 230

.. 558 2 ....... 13,700

.. 540 3 ....... 18,600

..524 4 ....... 7,790

	5 ....... 4,240

Inflow Feb. 17 to Mar. 5 in acre-feet...100,200 

Inflow, In second-feet, at Indicated time, 1938

17

18

19

20

21

22

23

24

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

March 2

200

200

240

28C

350

500

720

1,000

1,350

1,470

1,540

1,700 .

2,000

2,580

3,000

3,400

4,100

34,500

61,000

57 , 800

51,400

44,000

38,300

35,300

March 3

33,600

29,700

27,600

24,800

21,600

21,000

20,100

18,400

17,200

16,500

16,300

16,500

16,400

16,100

15,800

15,400

14,900

14,400

13,900

13,300

13,000

12,500

12,000

11,200

March 4

10,500

10,000

9,660

9,240

9,030

8,860

8,660

8,500

8,260

8,050

7,900

7,750

7,600

7,500

7,320

7,200

7,060

6,960

6,400

5,850

5,640

5,400

5,180

5,020

March 5

4,770

4,580

4,500

4,330

4,240

4,120

4,040

3,980

3,940

3,910

3,880

3,880

Supplemental record.- Mar. 2, 7:25 p.m., 66,200 sec.-ft.
BASIC DISCHARGE RECORDS

Mean dally outflow, in second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

3.8

3.3

5.5

7

6

5.5

4.2

25

72

85

Mar.

205

12,730

21,660

8,620

4,520

3,900

3,840

4,460

4,940

2,670

Apr.

860

1,330

1,280

1,640

2,410

2,620

2,500

2,320

2,290

2,010

Day

11

12

13

14

15

16

17

18

19

20

Feb.

89

92

89

89

88

88

88

88

89

92

Mar.

1,620

1,950

2,690

2,700

2,380

1,920

1,140

1,760

1,750

1,420

Apr.

1,190

462

418

414

414

383

392

395

397

400

Day

21

22

23

24

25

26

27

28

29

30

31

Outflow, in acre-feet ..........................................

Feb.

94

98

99

170

341

308

180

86

QQ Q

4,930

Mar.

700

580

1,030

1,360

1,300

1,300

1,210

1,310

1,310

1,310

790

196,500

Apr.

403

406

409

343

96

13

12

9.5

9

8.5

51,240

Outflow, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

H

March 2

45

60

60

60

75

105

165

255

390

615

735

855

1,020

1,290

1,600

5,230

13,500

20,200

50,400

55,500

51,800

46,200

39,600

33,500

March 3

32,200

28,700

28,500

27,300

20,200

20,800

20,500

19,500

16,200

16,500

17,500

21,300

20,500

21,000

20,500

21,200

21,500

19,500

18,300

19,400

19,400

19,300

18,700

16,700

March 4

13,800

12,100

11,000

10,300

9,860

9,500

9,200

8,960

8,700

8,500

8,300

8,100

8,000

7,800

7,600

7,500

7,400

7,300

7,050

6,700

6,350

6,100

5,900

5,650

March 5

5,250

5,000

4,830

4,630

4,500

4,400

4,360

4,250

4,160

4,060

4,020

4,000

Supplemental records.- Mar. 2, 7:05 p.m., 65,700 sec.-ft.; 

7:12 p.m., 65,400 sec.-ft.; 7:20 p.m., 51,800 sec.-ft.; 8:25 

p.m., 56,300 sec.-ft.

West Pork of San Gabriel River at flood-control reservoir No.2, near Camp Rincon, Calif.

Location.- Staff gage, lat. 34°14'45n , long. 117°57 '50" , near center sec. 19, T. 2 N. , 

R. 10 W., 6 miles west of Camp Rincon. Altitude of stream bed, 2,140 feet.

Drainage area.- Area, 40.4 square miles. Average altitude, 4,290 feet. Maximum altitude , 8,038 feet. Average slope, 47 percent. Length of main stream channel, 8.5 

miles. Average slope of main stream channel, 13 percent.

Gage-height record.- Staff gage read daily at 8 a.m.; more frequently during storm 

period.

Discharge record.- Computed from spillway rating curve, valve rating curves, valve operation record, record of stage, discharge measurements^ and changes in storage based 

on record of stage and stage -capacity tables; stage -capacity table dated October 

1935 used to time of peak stage of Mar. 2 (4:30 p.m.), and table corrected by silt 

survey made after storm used thereafter.

Maxima.- 1938: Inflow, 26,900 second-feet 4:15 p.m. Mar. 2. 

Outflow, 24,200 second-feet 4:30 p.m. Mar. 2.

Remarks.- Records good. Altitude of spillway, 2,385 feet. Area at spillway level, 

143 acres. Capacity at spillway level before storm of Mar. 2, IS, 298 acre-feet; 

after storm, 10,787 acre-feet. Basic data Feb. 27 to Mar. 11 and entire record 

Feb. 1-26 and Mar. 12 to Apr. 30 furnished by Los Angeles County Flood Control District through H. E. Hedger, chief engineer.
FLOODS OF MARCH 1938 IK SOUTHERN CALIFORNIA

Mean daily inflow, in second-feet, 1938

Day

1

Z

3

4

5

6

7

a

9

10

Feb.

93

39

346

305

132

70

54

46

107

109

Mar.

1,430

8,100

3,430

995

613

438

313

350

376

394

Apr.

107

101

100

99

95

94

79

79

77

75

Day

11

13

13

14

15

16

17

18

19

30

Feb.

549

388

163

113

91

71

61

75

73

62

liar.

346

853

539

469

388

331

376

364

338

327

Apr.

70

71

72

69

65

60

61

56

56

53

Day

31

23

33

34

25

36

37

28

39

30

31

Feb.

53

48

47

42

41

42

140

1,030

150

8,310

Mar.

303

197

190

185

178

155

155

163

145

126

111

673

41,350

Apr.

52

48

48

54

61

56

45

46

51

57

4,080

Inflow, in second-feet, at indicated time, 1938

Hr.

1

3

3

4

5

6

7

8

9

10

11

N

1

3

3

4

S

6

7

8

9

10

11

M

Feb. 37

45

45

45

46

46

46

46

46

55

65

77

95

133

162

304

330

246

260

284

369

263

359

255

350

Feb. 38

348

344

343

367

330

425

625

960

1,060

1,130

1,170

1,200

1,330

1,300

1,580

1,160

890

950

985

1,040

1,180

1,940

2,850

3,450

Mar. 1

4,600

3,350

3,730

3,300

1,860

1,680

1,540

1,400

1,300

1,040

915

880

860

843

830

820

806

798

787

775

763

735

695

680

Mar. 3

705

735

780

850

1,180

1,940

3,580

3,600

5,100

8,600

9,300

10,300

10,800

30,000

31,800

34,700

20,300

13,000

10,000

8,050

6,500

5,700

5,300

4,730

Mar. 3

4,350

3,860

3,430

3,240

3,020

2,870

3,700

3,550

3,400

2,370

2,170

3,100

2,010

1,930

1,850

1,790

1,700

1,650

1,590

1,510

1,460

1,410

1,370

1^330

Mar. 4

1,290

1,350

1,180

1,130

1,040

975

905

850

805

765

733

730

Mar. 5

698

675

640

550

505

490

Mar. 6

485

480

470

370

350

333

Mar. 7

326

311

300

300

337

295

Mar. 8

282

273

387

308

375

392

410

435

455

360

320

300

Supplemental record.- Mar. 3, 4!15 p.m., 36,900 sec.-ft.

Mean dally outflow, In second-feet, 1938

Day

1

8

3

4

5

6

7

8

9

10

Feb.

7.5

9

13

36

30

38

36

35

33

35

Mar.

181

6,810

3,980

1,655

741

733

860

934

1,390

533

Apr.

97

96

96

95

95

94

74

56

34

7

Day

11

13

13

14

15

16

17

18

19

30

Feb.

30

38

34

34

34

33

30

38

36

24

Mar.

123

540

333

383

192

14

15

84

129

155

Apr.

6

6

6

6.5

7

7

7

7

7

7

Day

31

28

33

24

35

36

37

38

29

30

31

Feb.

33

32

33

31

20

30

31

31

1,390

Mar.

235

286

388

386

282

266

368

373

177

135

93

41,970

Apr.

7.5

8

7.5

8

8.5

9

9

9

9

9

1,760

Outflow, In second-feet, at indicated tins, 1938

Hour

1

3

3

4

5

6

7

8

9

10

11

N

1

3

3

4

5

6

7

8

9

10

11

M

February 37

20

30

20

30

31

31

21

31

31

31

21

22

February 38

33

32

33

33

36

39

33

37

39

43

45

52

March 1

65

75

82

87

90

92

94

95

236

377

378

380

381

382

March 2

386

387

392

397

403

411

423

4,150

6,430

6,840

14,500

19,600

22,800

23,400

. 16,700

12,300

9,530

7,730

6,430

6,710

7,550

March 3

7,050

5,050

3,730

3,460

3,270

3,170

3,060

2,860

2,710

2,610

2,420

2,380

2,320

2,280

2,240

2,230

2,230

2,210

2,200

2,190

March 4

2,170

2,150

2,140

2,120

2,100

2,070.

2,050

2,020

654

654

657

658

659
BASIC DISCHARGE RECORDS 111

Outflow, in second-feet, at indicated time, 1938 Continued

Hour

2

4

6

8

10

H

2

4

6

8

10

M

March 5

659

660

660

660

927

924

921

March 6

915

905

25

25

911

910

903

695

March 7

883

871

861

861

850

840

832

March 8

821

813

18

18

1,770

1,720

1,670

March 9

1,610

1,510

1,420

646

641

321

1,420

1,390

March 10

1,330

1,290

260

7

7

7

337

335

Supplemental record.- Mar. 2, 4:30 p.m., 24,200 sec.-ft.

Sawpit Creek at flood-contrcl reservoir near Monrovia, Calif.

Location.- Water-stage recorder, lat. 34°10 t 3011 , long. 117059'00", near center sec. 13, 

T. IN., R. 11 W., 2 miles north of Monrovia. Altitude of stream bed, 1,228 feet.

Drainage area.- Area, 3.27 square miles. Average altitude, 2,960 feet. Maximum altitude, 5,390 feet. Average slope, 50 percent. Length of main stream channel, 3.1 

miles. Average slope of main stream channel, 25 percent.

Gage-height record.- Water-stage recorder graph and frequent staff-gage readings.

Discharge record.- Computed from spillway rating curve, valve rating curves, valve operation records, record of stage, discharge measurements, and stage-capacity tables; 

stage-capacity table based on survey of October 1935 used to time of peak stage of 

Mar. 2 (6 p.m.), table corrected by silt survey made after storm used thereafter.

Maxima.- 1938: Inflow, 1,000 second-feet 4:15 p.m. Mar. 2.

Outflow, 665 second-feet 6 p.m. Mar. 2. 

1932-37: Mean hourly inflow, 240 second-feet 2-3 a.m. Jan. 1, 1934.

Remarks.- Records fair. Altitude of spillway, 1,360 feet. Area at spillway level, 

7.9 acres (after storm of Mar. 2). Capacity at spillway level before storm, 369 

acre-feet; after storm, 320 acre-feet. Basic data Feb. 27 to Mar. 11 and entire 

record for rest of February, March, and April furnished by Los Angeles County Flood 

Control District, through H. E. Hedger, cMef engineer.

Mean daily inflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

3.4

1.4

22

16

6

3.0

2.1

1.0

4.2

4.6

Mar.

83

371

132

54

35

34

27

17

15

15

Apr.

8

8

7.5

7.5

7.5

7

6.5

6

6

6

Day

11

12

13

14

15

16

17

18

19

20

Feb.

9.5

9

6

4.8

3.3

3.3

3.2

3.1

3.0

2.4

Mar.

. 14

81

17

15

14

14

13

13

12

11

Apr.

5.5

5.5

5.5

5.5

5.5

5

5

5

5

4.9

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

1.5

1.2

1.4

1.5

1.4

1.0

1.3

44

5.88

326

Mar.

11

10

9.5

9

8.5

8.5

8.5

8.5

8.5

8.5

8.5

»» 1

2,040

Apr.

4.8

4.8

4.8

5

5

4.4

3.9

3.4

3.4

3.3

5.51

328

Inflow, in second-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

0.9

.9

.9

.9

.9

.9

1.0

1.4

2.7

2.1

1.6

1.3

.8

1.0

1.3

1.4

1.4

1.4

1.4

1.4

1.4

1.4

1.4

1.6

Feb. 28

2.1

3.2

5.5

13

22

31

42

60

73.

68

63

58

54

39

31

25

23

22

21

19

32

120

156

170

Mar.l

245

183

151

128

110

97

87

81

75

68

62

59

57

54

50

47

46

44

43

42

40

41

44

47

Mar. 2

49

51

52

58

76

99

156

180

260

314

320

455

515

615

800

925

815

680

620

575

470

352

300

265

Mar. 3

240

220

205

196

185

174

163

150

134

129

122

115

106

97

93

90

87

84

83

82

81

80

79

79

Mar. 4

68

64

60

57

54

52

50

48

46

44

42

40

Mar. 5

38

36

34

33

32

33

Mar. 6

35

36

36

34

32

32

Mar. 7

31

30

26

23

20

19

Mar. 8

18

17

17

17

16

16

Mar. 9

16

16

15

15

15

15

Mar .<10

14

14

13

13

13

20

Supplemental record.- Mar. 2, 5:15 p.m., 1,000 sec.-ft.
FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Mean daily outflow, In second-feet, 1958

Day

1

2

5

4

5

6

7

8

9

10

Feb.

0

0

2.9

16

8.5

7

4.5

8

9.5

0

Mar.

63

231

149

75

71

68

59

27

16

15

Apr.

9

7.5

7.5

8

7

7

6.5

6

5.5

5.5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

7

9.5

9.5

7.5

4.9

4.4

4.1

1.7

0

0

Mar.

13

20

17

15

15

14

13

12

11

11

Apr.

6

5.5

5.5

5.5

5.5

5.5

5

5

5

4.9

Day

21

22

23

24

25

26

27

28

29

50

51

Feb.

0

0

0

0

0

0

5.5

16

4.52

251

Mar.

10

10

13

9

8

8.5

8.5

8.5

9

8.5

8

32.8

2,020

Apr.

4.8

4.8

4.8

5

5

4.6

3.9

3.2

3.4

5.2

5.52

328

Outflow, in second-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

0

0

0

0

0

0

0

0

0

0

5

10

10

10

10

10

10

10

Feb. 28

10

10

10

10

10

10

16

19

7

13

15

20

20

20

28

38

44

Mar.l

53

58

62

63

64

65

65

65

65

64

64

63

63

63

Mar. 2

62

61

62

64

66

68

103

105

108

256

318

583

665

649

618

502

403

333

303

Mar. 3

276

251

231

216

200

165

145

130

111

100

100

93

90

87

Mar. 4

80

74

74

74

74

74

74

73

73

73

73

Mar. 5

 72

72

71

71

70

70

Mar. 6.

69

68

68

67

66

66

Mar. 7

65

64

62

&

52

48

Mar. 8

44

40

26

17

17

17

Mar. 9

17

17

16

15

15

15

Mar.10

15

15

15

15

15

14

San Dimas Creek at flood-control reservoir near San Dimas, Calif.

Location.- Water-stage recorder, lat. 34°09'15", 

N., R. 9 W., 4 miles northeast of San Dimas.

long. 117°46'15", in SEi sec. 24, T. 1 

Altitude of stream bed, 1,350 feet.

Drainage area.- Area, 16.5 square miles. Average altitude, 5,150 feet. Maximum altitude, 5,558 feet. Average slope, 42 percent. Length of main stream channel, 6 miles. 

Average slope of main stream channel, 15 percent.

Qage-helght record.- Water-stage recorder graph and staff-gage readings.

Discharge record.- Computed from spillway rating curve, valve rating curves, valve operation record, record of stage, and stage-capacity tables; stage-capacity table based 

on survey of December 1955 used to time of peak stage on Mar. 2 (5:15 p.m.), table 

corrected by silt survey made after storm used thereafter.

Maxima.- 1958: Inflow, 4,600 second-feet 5:10 p.m. Mar. 2.

Outflow, 4,570 second-feet 5:15 p.m. Mar. 2. 

1952-57: Mean hourly inflow, 422 second-feet 5-4 a.m. Jan. 1, 1954.

Remarks.- Records fair. Altitude of spillway, 1,462 feet. Area at spillway level, 56 

acres (after storm of Mar. 2). Capacity of spillway level before storm, 1,599 acrefeet; after storm, 1,188 acre-feet. Basic data Feb. 27 to Mar. 2 and entire record 

for rest of February, March, and April furnished by Los Angeles County Flood Control 

District, through H. E. Hedger, chief engineer.

Mean dally inflow, in aeeond-feet, 1958

Day

1

2

5

4

5

6

7

8

9

10

Feb.

15

5.5

52

50

15

8

5.5

5.5

15

15

Mar.

551

1,580

461

191

155

95

77

76

61

54

Apr.

51

50

28

28

26

25

24

25

22

21

Day

11

12

15

14

15

16

17

18

19

20

Feb.

42

54

18

15

10

9

8

8

7.5

5.5

Mar.

50

121

116

97

83

72

66

58

59

55

Apr.

21

22

20

17

15

16

15

14

15

16

Day

21

22

23

24

25

26

27

28

29

50

31

Feb.

6

6

4.9

5.7

5.7

5

11

144

17.2

956

Mar.

51

48

44

45

42

58

57

56

36

33

32

8,480

Apr.

15

15

14

17

18

15

15

15

15

15

TO A

1,160
BASIC DISCHARGE RECORDS 118

Inflow, In second-feet, at Indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

5

5

6

13

16

14

13

14

14

12

11

14

Feb. 28

20

34

58

93

170

167

171

181

170

160

149

132

139

159

230

410

790

Mar.l

1,420

1,270

770

545

430

360

300

265

232

218

205

183

167

150

140

130

120

111

104

98

92

87

86

88

Mar. 2

97

108

121

139

160

219

343

500

710

1,220

1,700

1,730

2,090

3,200

4,100

4,010

4,200

3,850

2,600

2,300

1,900

1,280

1,010

870

liar. 3

800

705

600

530

441

363

330

314

298

293

284

270

liar. 4

247

219

210

200

192

183

177

170

165

161

157

154

Mar. 5

154

156

157 -

156

150

138

120

116

114

113

110

108

Mar. 6

102

97

93

92

88

84

Mar. 7

82

79

77

74

74

72

Mar. 8

74

78

80

80

73

66

Mar. 9

63

62

61

60

59

60

M&$5-

' 58

55

53

52

50

50

Supplemental record.- liar. 2, 5>10 p.m., 4,600 sec.-ft.

Mean dally outflow, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb. '

0

0

0

0

0

0

0

0

0

0

Mar.

235

1,290

720

319

193

106

96

70

68

47

Apr.

30

26

26

26

25

25

24

24

24

23

Day

11

12

13

14

15

16

17

18

19

20

Feb.

0

6

14

15

14

10

11

6.5

0

0

Mar.

38

76

109

128

109

68

61

32

80

64

Apr.

23

23

7.5

0

0

0

0

0

.8

2.1

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

5

74

5.56

308

Mar.

53

53

47

44

44

43

37

 32

32

32

32

8,640

Apr.

2.1

2.1

2.1

1.6

0

0

3.0

9

12

.12

11.8

700

Outflow, In second-feet at Indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

0

0

0

18

18

18

18

Feb. 28

18

18

19

19

19

110

110

110

110

110

110

110

111

Mar.l

113

115

120

255

255

255

255

255

255

255

255

252

250

250

Mar.2

250

248

248

248

250

458

785

798

830

2,370

3,700

4,150

4,200

2,850

2,630

2,350

1,560

1,240

1,090

Mar. 3

995

1,090

1,120

960

780

720

717

710

702

695

685

675

330

330

328

Mar. 4

328

325

325

325

323

320

318

316

314

311

308

305

Mar. 5

300

295

287

0

0

145

145

125

105

Mar. 6

105

105

105

105

105

104

Mar. 7

103

103

103

102

102

69

69

Mar. 8

69

69

69

70

70

70

Mar. 9

69

69

69

69

69

69

Har.Kf

68

g"2

36

56

36

36

Supplemental record.- Mar. 2, 5:15 p.m., 4,370 sec.-ft.
114 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Fern Canyon Watershed No. 2, near San Dimas, Calif.

Location.- Water-stage recorders and flume, lat. 34° 11'55", long. .117°42'08", In sec. 

3, T. 1 N., R. 8 W., in San Dimas Experimental Foreet, about 8 miles northeast of 

San Dimas. Altitude, about 4,500 feet.

Drainage area.- Area, 0.063 square mile. Average altitude, 5,000 feet. Maximum altitude, 6,400 feet. Average slope, 65 percent. Length of main stream channel, 0.41 

mile. Average slope of main stream channel, 42 percent.

Sage-height record.- Water-stage recorder graphs.

Discharge record.- The runoff is measured by a modified 3-foot Farshall flume and 

represents the inflow into a small concrete-lined reservoir of 10,000-cubic-foot 

capacity. A 90° V-notch weir is used in conjunction with flume for low flows. 

Ratings of flume and weir used throughout the period.

Maximum.- 1938: Discharge, 28.8 second-feet 4 p.m. liar. 2. 

Remarks.- Records furnished toy U. S. Forest Service.

Mean daily discharge, in second-feet, 1938

Feb. 27 ....... 0.004

28 ....... 2.02

Mar. 1 ....... 1.38

2 ....... 8.62

3 ....... 2.52

4 ....... .592

Mar. 5 ....... 0.221

6

7

8

9

10

Runoff Feb. 27 to Mar. 10, in acre-feet.

.090

.044

.033

.027

.023

30.9

Discharge, in second-feet, at indicated time, 1938

Time Discharge

February 27

9 am

9:30

10

12 m

1 pm

2

4

6

7

7:30

8

10

12

0

.004

.003

.006

.005

.008

.006

.007

.008

.018

.008

.010

.008

February 28

1 am

2

3

4

5

6

7

7:30

8

9

10

10:30

.014

.020

.027

.046

.062

.159

.240

.225

.515

.921

1.10

1.22

Time

10:35

11

12 m

1 pm

2

Discharge

1.22 

.955

.991

1.18

1.81

2:30 2.94

3

4

5

6

6:30

8

9

10

11

12

Ma

12:15

1

2

3

4

6

7

8

9

10

3.50

3.88

3.50

3.05

3*2*7

2.83

3.28

5.90

7.32

7.60

rchl

am 7.60

5.58

3.85

3.00

2.32

1.76

1.48

1.26

1.06

.897

Time

11 

12 m

Discharge

0.790 

.700

1 pm .617

2

3

4

6

8

10

11:30

12

Mar

.539

.468

.424

.352

.289

.240

.218

.240

oh 2

1 am .334

2

3

4

5

6

7

8

9

9:30

10

11

11:30

12 m

.289

.324

.445

.590

.955

1.34

1.97

2.83

3.70

5.18

8.20

6.70

8.30

]2:lSpmll.30

Time Discharge

12:30 15.25 

12:45 12.2

1 15.0

1:30 18.5

1:45

2

2:30

2:45

3

3:30

3:45

4

4:15

16.8

19.0

25.4

20.6

27.8

18.8

25.0

28.8

26.5

4:30 28.2

4:50

5

5:30

6

21.6

25.6

22.0

18.0

6:30 15.0

7

8

9

10

11

12

13.4

10.5

8.30

7.10

5.95

5.18

March 5

2 am 4".20

Time Discharge

6 3.50 

10:50 3.35

11:15

12 m

2.00

1.92

2 pm 1.71

3

4

5:30

6

6:15

1.57

1.-48

1.39

1.46

1.30

6:30 1.43

7

8

8s 15

8:30

9

10

12

1.30

1.18

1.16

1.18

1.14

1.04

.955

March 4

2 am

4

6

8

10

12 m

4

8

.887

.790

.715

.658

.617

.564

.460

.403-

Time

12

Discharge

0.343

March 5 6~am

12 m

.264

.211

6 pm .171

12 .130

March 6

6 am

12 m

 T106

.088

12 -pm .058

March 7

12 m .041

12 pm .036

Mar 12~m~

12 pm

ch 8 T033

.030

March 9

12 m .027

12 pm .025

Mar

S'sSS

ch 10

am. 023

Fern Canyon Watershed No. 3, near San Dimas, Calif.

Location.- Water-stage recorders and flume, lat. 34°11'5311 , long. 117°42'0911 , in San 

Dimas Experimental Forest, about 8 miles northeast of San Dimas. Altitude, about 

4,500 feet.

Drainage area.- Area, 0.084 squars mile. Average altitude, 5,000 feet. Maximum altitude, 5,400 feet. Average slope, 65 percent. Length of main stream channel, 0.52 

mile. Average slope of main stream channel, 33 percent.

Sage-height record.- Water-stage recorder graphs.

Discharge record.- The runoff is measured by a modified 3-foot Parshall flume and 

represents the inflow into a small concrete-lined reservoir of 10,000-oubio-foot 

capacity. A 90° V-notch weir is used in conjunction with flume for low flows. Ratings of flume and weir used throughout the period.

Maximum.- 1938: Discharge, 19.0 second-feet 4 and 4:15 p.m. Mar. 2. 

Remarks.- Records furnished by 0. S. Forest Service.
BASIC DISCHARGE RECORDS 115

Mean daily discharge, in second-feet, 1938

Feb. 27 ....... 0.001

28 ....... .616

Mar. 1 ....... 1.15

2 ....... 5.10

3 ....... 1.75

4 ....... .527

liar. 5 ....... 0.152

6 ....... .036

7 ....... .010

8 ....... .005

9 ....... .003

10 ....... .001

Runoff, Feb. 27 to Mar. 10, in acre-feet. 18.5

Discharge, in second-feet, at indicated time, 1938

«- charge

February 27

2 am 0

3 .001

6 0

8 .001

9:30 .004

12 m .001

1 pm .002

2 .001

3 .003

8 .001

10 .002

12 .001

February 28

ETam \15D4

3:30 .004

5 .007

6 .032

7 .072

8 .096

9 .125

10 .184

10:30 .240

 Mm* Dl8 "

Tlme charge

11 0.468

12 m .539

1 pm .672

2 .854

3 1.030

3:45 .921

4 1.010

5 .790

6 .617

6:30 .672

7 .590

8 .515

9 .590

9:30 .822

10 1.700

11 2.80

12 4.60

March 1

12s30tm5.75

1 5.18

2 4.00

3 3.20

T1« charge

4 2.32

6 1.55

7 1.40

8 1.12

9 .980

10 .850

11 .445

12 m .362

1 pm .306

2 .248

4 .118

6 .125

8 .092

11 .065

12 .072

March 2 l~am TOBO

2:30 .072

4 .106

5 .171

6 .256

7 .760

«- change

8 1.70

10 4.00

11 6.15

11:30 5.58

12 m 5.95

1 pm 8.30

1:30 10.9

1:50 13.4

2 12.2

2:30 16.5

3 18.5

3:15 13.2

3:30 16.8

3:45 15.0

4 19.0

4:10 17.2

4:15 19.0

4:30 15.0

4:45 8.90

5 15.0

5:30 12.2

6 8.30

6:20 6.35

_. Dis- Tlme charge

6:40 7.10

7 6.35

8 4.40

12 2.50

12~m March  1784 3

2 pm 1.61

4 1.43

5:30 1.34

6 1.43

6:15 1.28

6:30 1.39

7 1.26

8 1.18

12 .921

March 4

2 am .822

10 .539

4 pm .403

8 .324

12 .264

_. Dia- Tlme charge

March 5

6 am 0.207

12 m .141

6 pm .096

12 .065

March 6

6 am .046-

12 m .032

6 pm .023

12 .018

March 7

12~m TOOS

12 pm .007

March 8 12~m T005

12 pm .004

March 9 12~m T003

12 pm .002

March 10

10.30 am .001

Wolfskill Creek near San Dimas, Calif.

Location.- Water-stage recorders and flume, lat. 340 10 I 35", long. 117°45'25", in sec. 

18 T. 1 N., R. 8 W., in San Dimas Experimental Forest, about 5.5 miles northeast of 

San Dimas. Altitude, about 1,700 feet.

Drainage area.- Area, 2.78 square miles. Average altitude, 3,460 feet. Maximum altitude, 5,200 feet. Average slope, 49 percent. Length of main stream channel, 3.5 

miles. Average slope of main stream channel, 19 percent.

Page-height record.- Water-stage recorder graph.

Discharge record.- The runoff is measured by e 10-foot modified Parshall flume and a 

2-foot San Dimas flume for lower flows. Rating of flumes used throughout the 

period.

Maximum.- 1938: Discharge, 630 second-feet 2:43 p.m. Mar. 2. 

Remarks.- Records furnished by U. S. Forest Service.

Mean daily discharge, in second-feet, 1938

Feb. 27 ....... 1.2

28 ....... 13.5

Mar. 1 ....... 34.8
U6 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Discharge, in second-feet, at indicated time, 1938

Time

Discharge

February 27

8 am

9

10

12 m

4 pm

12

0.7

1.0

1.4

1.6

1.4

1.3

February 28

1 am

1:30

2

2:30

3

3:30

4

4:30

5

5:30

6

6:30

7

7:30

7:45

8

8J30

9

9:30

I7F

1.7

S.O

S.I

2.5

S.9

3.6

4.7

5.3

6.1

7.0

7.9

8.0

8.0

8.6

9.9

11.5

13.0

16.5

Time

9:50

10

11

12 m

12:30

IS: 30

1

2

2:30

3

3:30

3:45

4

4:30

4:45

6:30

6:50

7

7:30

8

8:30

8:40

8:50

9

9:30

10

10:30

11

Discharge

20.2

16.5

12.5

16.2

pm 14.5

17.5

27.8

17.0

27.2

22.2

18.7

20.0

18.7

19.4

20.8

18.9

19.0

18.9

17.9

17.6

17.3

17.3

17.1

17.4

19.6

22.0

24.8

31.6

Time

11:30

12

Discharge

35.5

66.0

March 1

12:30 am 130

12:45

1

2

3

3:30

4

4:30

5

6

8

9

10

11

12 m

2 pm

4

6

8

10

12

137

130

108

93.0

84.0

76.0

66.0

51.7

42.0

39.2

30.2

27.0

25.4

21.0

15.5

10.5

8.5

5.6

3.3

1.0

March 2.

2 am

 2.3

Time

3

4

5

5:30

6

6:10

Discharge

3.6

6.6

14.2

16.8

21.6

18.1

6:20 18.1

6:30 20.5

6:40 20.5

6:50

7

7:10

18.1

18.1

19.7

7:20 25.7

7:30

8:10

27.0

27.0

8:20 30.2

8:30

8:40

39.6

53.0

8:50 57.0

9 76.0

9:10 66.0

9:20 76.0

9:30 78.0

9:40 118

9:50 106

10 127

10:10 165

10t20 180

Time

10:30

10:40

10:50

11

11:10

11:20

11:30

11:40

11:50

12 m

12:10

12:20

Discharge

225

255

270

289

340

330

307

304

311

300

300

289

12:30 307

12:40

12:50

307

327

1 pm 327

1:10

1:20

330

420

1:30 370

1:40 430

1:50 430

2

2:10

2:20

460

490

543

2:30 635

2:40 795

2:43 830

2:50 655

Time

3:00

3:1C

Discharge

590

741

3:20 645

3:30 590

3:40 543

3:5C

4

530

515

4:10 440

4:20 505

4:3C 520

4:40 615

4:5C

5

5:10

365

515

490

5:20 520

5:30 480

5:4C

, 5:5C

6

6:1C

460

505

520

450

6:20 430

6:30 355

6:40 355

6:5C

7

335

327

7:10 240

West Fork of San Dimas Creek near San Dlmas, Calif.

Location.- Water-stage recorders and flumes, lat. 34°10'lo", long. 117 0 46'15", in 

3E-£SEt, sec. 13, T. 1 N., R. 9 W., In San Dlmas Experimental Forest, about 4.5 

miles northeast of San Dlmas. Altitude, about 1,600 feet.

Drainage area.- Area, 1.66 square miles. Average altitude, 2,360 feet. Maximum alti- 

*tude, 3,100 feet. Average slope, 47 percent. Length of main stream channel, 2.5 

miles. Average slope cf main stream channel, 11.4 percent.

Page-height record.- Water-stage recorder graph.

Pis charge re e ord.- The runoff is measured by a 10-foot modified Parshall flume and a 

2-foot San Dimas flume for lower flows. Rating of flumes used throughout the 

period.

Maximum.- 1938: Discharge, 664 second-feet 4:05 p.m. Mar. 2. 

Remarks.- Records furnished by U. S. Forest Service.

Mean dally discharge, In second-feet, 1938

Feb. 27 ....... 1.1

28 ....... 16.3

Mar. 1 ....... 41.4

Discharge, in second-feet, at indicated time, 1938

Time Discharge

February 27

7 am

9

9:30

10

11

12

1 pm

2

3

4

5

6

7

8

12

0.5

.8

1.4

1.9

2.4

2.3

1.8

1.6

1.4

1.4

1.4

1.3

1.2

1.2

1.0

February 28

1 am

1:20

1:40

2

2:20

2:40

3

3:30

4

4:30

5

1.6

1.9

2.3

2.9

3.5

4.1

4.1

4.2

4.7

5.3

6.1

Time

5:50

6

7

8

12 m

1

2

3

4

5

6

7

7:30

8

8:30

9

9s30

10

Mar

Discharge

7.3

7.8

9.4

13.1

24.0

20.7

20.4

19.0

16.9

15.4

15.0

14.5

14.1

13.8

14.2

16.1

21.2

31.5

oh 1

12:15am49.0

12:30

1

1:30

2

2:10

2:20

2:40

3

76.0

225

180

107

102

100

91.0

82.5

Time Discharge

3:20 78.5

4

5

63 '.8

49.0

6:20 38.9

7 41.9

8:40 45.9

9

10

11

12 m

44.8

34.0

29.5

26.5

1 pm 23.4

2

4

5

7

9

10

12

Mar

21.0

20.2

18.1

17.8

16.2

14.2

14.0

oh 2

4 am 14.0

5 15.0

5:30 16.8

6 27.8

6:30 38.5

7 53.0

7:20 57.0

7:4C

8

61.5

63.8

Time Discharge

8:20 68.5

8:40 78.5

8:5C

9

9:1C

101

112

118

9:20 124

9:50 142

9:40 152

9:5e

10

164

184

10:10 214

10:2C

10:25

10:35

236

248

261

10:40 259

10:5C

11

11:05

248

229

195

11:10 174

ll:2C 164

11:40 160

12 m 166

12 : 10pml77

12:2C 195

12:30 206

12:4C 219

12:50 232

1 244

1:10 259

Time Discharge

1:20 270

1:30 281

l:4C

1:45

l:5C

1:55

2

308

340

315

297

311

2:10 322

2:2C

2:25

330

360

2:30 390

2:4C 425

2:50 460

2:55 500

3

3:05

3:1C

3:15

530

580

610

585

3:20 558

3:3C 585

3:45 595

3:5C 568

3:55 615

4

4:05

4:1C

650

664

630

4:15 530

4:2C 475

Time Discharge

4:25 355

4:35 378

4:4£ 330

4:50 390

4:5E

5

5:1C

450

470

492

5:20 415

5:3C

5:4C

350

300

5:45 254

5:5C 289

5:55 322

6 292

6:10 251

6:2C

6:3C

232

221

6:40 215

6:50 206

7 180

7:10 164

7:3C

8

8:3C

9

9:3C

10

157

145

130

112

104

101
BASIC DISCHARGE RECORDS 117

Dalton Creek at flood-control reservoir near Glendora, Calif.

Location.- Water-stage recorder, lat. 34°10'1011 , long. 117 0 48'30", near center sec. 15, 

mm., R. 9 W., 3& miles northeast of Glendora. Altitude of stream bed, 1,565 

feet.

Drainage area.- Area, 4.49 square miles. Average altitude, 2,590 feet. Maximum altitude, 3,6C6 feet. Average slope, 40 percent. Length of main stream channel, 3.5 

miles. Average slope of main stream channel, 11 percent.

Gage-height record.- Water-stage recorder graph and frequent staff -gage readings. 

Discharge record.- Computed from valve rating curves, valve operation records, record

of stage, discharge measurements, and stage-capacity tables; stage-capacity table 

based on survey of November 1934 used to time of peak stage cf Mar. r 2 (8:30 p.m.), 

table corrected by silt survey made after storm used thereafter.

Maxima.- 1938: Inflow, 1,350 second-feet 3:15 p.m. Mar. 2.

Outflow, 739 second-feet 6 p.m. Mar. 2. 

1929-37: Mean hourly inflow, 227 second-feet 3-4 a.m. Jan. 1, 1934.

Remarks.- Records good. Altitude of spillway, 1,706 feet. Area at spillway level, 23 

acres {after storm cf Mar. 2). Capacity at spillway level before storm, 1,040 acrefeet; after storm, 974 acre-feet. Basic data Feb. 27 to Mar. 10 and complete record for rest of February, March, and April furnished by Los Angeles County Flood 

Control District, through H. E. Hedger, chief engineer.

Mean daily inflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

1.6

.6

7

5

1.9

1.6

l.S

1.3

3.2

2.5

Mar.

101

416

147

67

45

37

31

31

22

17

Apr.

5

6

5

5

5

4.5

4.5

3.7

3.9

4.5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

8.5

8

5.5

3.4

2.7

2

2.1

2

2.7

2

Mar.

15

39

38

33

27

20

18

14

11

11

Apr.

4.5

4.7

4.7

3.9

4

4

4

3.4

3.3

3.3

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

1.6

1.6

.8

1.1

1.2

.8

2.8

50

247

Mar.

9

8.5

7

8.5

9.5

9.5

9.5

10

8

7

7

2,450

Apr.

3.3

3.4

3.4

3.4

3.5

3.5

3.5

2.6

3.6

3.6

4.02

239

Inflow, in second-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

0

0

.8

.8

.8

.8

1.0

2.8

4.8

6

8.5

6

4.8

3.6

2.4

2.2

2.1

2.2

2.4

2.6

2.8

3.1

3.5

3.9

Feb. 28

4.8

7

9.5

11

11

13

44

55

54

54

54

57

64

57

49

45

43

41

43

46

55

90

170

260

Mar.l

370

275

235

218

150

103

95

86

82

75

67

60

54

50

48

46

45

43

42

40

38

36

33

36

Mar. 2

45

47

50

60

81

105

140

210

313

405

520

550

570

645

a, 080

1,100

1,000

780

630

520

430

315

245

215

Mar. 3

207

190

180

170

163

161

195

215

187

172

161

153

146

139

130

122

117

109

103

98

94

90

86

86

Mar. 4

80

75

72

69

66

63

61

59

56

54

52

50

Mar. 5

49

47

45

43

42

40

Mar. 6

39

38

37

36

36

35

Mar. 7

' 32

30

29

29

30

31

Mar. 8

31

32

32

31

29

26

Mar. 9

25

24

22

21

19

18

Mar. 10

18

17

17

16

16

21

Supplemental record.- Mar. 2, 3:15 p.m., 1,350 sec.-ft.

Mean daily outflow, in second-feet, 1938

Day Feb.

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

10 0

Mar.

10

179

117

173

96

94

60

48

33

37

Apr.

4.5

4.5

4.5

4.5

4.5

4.5

4.5

4.5

2.3

0

Day

11

12.

13

14

15

16

17

18

19

20

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

14

16

16

16

18

25

25

21

12

10

Apr.

0

0-

0

0

0

0

0

0

0

0

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

10

10

10

6.5

5

5

9

12

8.5

7

6

35.8

2,200

Apr.

0

0

0

0

0

0

0

0

0

0

1.28

76
118 FLOODS OF MARCH 1938 IK SOUTHERN CALIFORNIA

Outflow, in second-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

II

Feb. 27

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Feb.28

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Mar.l

0

0

0

0

0

0

0

0

15

29

29

29

29

29

Mar .2

29

29

29

30

30

31

32

81

131

134

456

739

460

462

462

328

327

231

Mar. 3

138

138

138

138

83

83

84

84

84

84

84

84

84

112

123

106

123

140

140

140

140

140

244

346

Mar. 4

344

342

340

337

335

333

330

164

0

0

83

166

149

132

66

66

33

66

66

66

66

66

66

66

Mar. 5

66

66

0

66

112

111

110

109

Mar. 6

108

107

105

83

62

61

60

Mar. 7

60

60

60

60

60

59

Mar. 8

59

59

59

59

30

30

30

Mar. 9

30

30

29

29

43

43

43

Mar. 10

43

43

42

42

42

21

17

17

Supplemental records.- Mar. 2, 4:01 p.m., 449 sec. -ft.; 5:01 p.m., 732 seo.-ft.;

and 6:01 p.m., 458 sec. -ft.

Live Oak Creek at flood-control reservoir near La Verne, Calif.

cation.- Water-stage recorder, lat. 34°07'45", long. 117 0 44 t 45", in 

V . 1 N., R. 8 W., 24 miles northeast of La Verne. Altitude of str

feet.

sec. 32, 

tream bed, 1,430

Drainage area.- Area, 2.30 square miles. Average altitude, 2,220 feet. Maximum altitude, 3,694 feet. Average slope, 36 percent. Length of main stream channel, 2.75 

miles. Average slope of main stream channel, 16 percent.

Page-height record.- Water-stage recorder graph; staff -gage observations daily at 8 

a.m. and more frequently during storm periods.

Discharge record.- Computed from valve rating curve, valve operation record, record 

of stage, and stage-capacity tables; stage -capacity table based on survey of March 

1936 used to time of peak stage of Mar. 2 (6:20 p.m.), table based on survey of 

May 1938 used thereafter.

Maxima.- 1938: Inflow, 373 second-feet 3:45 p.m. Mar. 2.

Outflow, 200 second-feet ' about 5:30 p.m. Mar. 2. 

1936-37: Mean Inflow, 139 second-feet between 6 and 6:30 p.m. Feb. 6, 1937.

Remarks . - Records good for March and fair for February and April. Altitude of spillway, 1,497 feet. Area at spillway level, 11.6 acrss (May 1938). Capacity at 

spillway level before storm of Mar. 2, 242 acre-feet, after storm, 229 acre-feet. 

Basic data Feb. 27 to Mar. 12 and entire record Feb. 1-26 and Mar. 13 to Apr. 30 > 

furnished by Los Angeles County Flood Control District, through H. B. Hedger, chief 

engineer.

Mean daily inflow, in second-feet , 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.2

0

1.5

1.2

.5

.1

.1

.1

.9

.6

Mar.

28

148

35

13

10

6

4.4

3.1

3.0

3.3

Apr.

0.8

.7

.7

.7

.7

.5

.5

.5

.4

.4

Day

11

12

13

14

15

16

17

18

19

20

Feb.

4.9

3.3

1.2

.5

.5

.2

.2

.1

.1

.1

Mar.

3.2

13

11

6

4.9

4.1

3.4

2.8

2.3

2.1

Apr.

0.4

.4

.5

.5

.5

.4

.4

.4

.4

.4

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

.4

19

1.28

70.8

Mar.

1.9

1.7

1.5

1.3

1.2

1.1

1.1

1.2

1

1.1

.9 

10.3

636

Apr.

0.4

.4

.3

.6

1.2

.8

.6

.5

.5

.4 '

0.53

31.5
BASIC DISCHARGE RECORDS 119

Inflow, in second-feet, at indicated time, 1938

Hour

1

Z

3

4

5

6

7

8

9

10

11

N

1

Z

3

4

5

6

7

8

9

10

11

11

February 27

0

0

0

0

0 

0

0

1.0

1.3

1.2

.9

.7

.6

.5

.5

.4

.4

.3

.3

.3

.3

.3

.2

.2

February 28

0.1

.1

1.0 '

1.4

2.5

7.5

8.5

11

25

31

37

34

25

19

16

14

12

10

9

11

14

40

72

115

March 1

177

85

62

41

31

27

23

19

16

14

13

12

11

10

10

9.5

9

8

7

6

5

3.2

2.6

6

March 2

13

15

16

17

29

64

110

130

168

290

278

250

214

290

335

285

269

241

158

103

92

84

71 

54

March 3

46

42

41

39

40

* 53

56

49

43

58

34

31

30

29

29

28

27

26

25

23

21

20

19

18

Supplemental record.- liar. 2, 3:45 p.m., 373 sec.-ft. 

Mean daily outflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

26

82

55

22

19

17

15

13

6.5

3.2

Apr.

0

0

0

0

0

0

0

0

0

0

Day

11

12

13

14

15

16

17

18

19

20

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

3.2

7.5

7.5

5.5

5.5

5.5

5.5

5.0

2.8

3.3

Apr.

0

0

0

0

0

0

0

0

0

0

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

0

.7

1.39

Mar.

5.2

3.1

2.6

2.6

.8

0

0

0

0

0

0

10.4

639

Apr.

0

0

0

0

0

0

0

0

0

0

0

Outflow, in second-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

H

Feb. 27

0

0

Feb. 28

0

0

10

25

Mar.l

40

40

40

40

40

40

28

15

15

15

15

15

15

15

15

25

Mar. 2

25

25

25

25

25

50

75

75

75

88

150

162

195

195

175

150

113

100

88

75

Mar .3

75

75

75

75

74

74

74

25

25

25

25

25

25

Mar. 4

25

25

25

25

25

19

19

19

19

19

19

19

19

Mar. 5

19

19

19

19

18

18

Mar. 6

18

18

17

17

17

16

Mar. 7

16

16

16

15

15

15

Mar. 8

14

14

13

13

13

12

Mar. 9

12

12

4.5

3.2

3.2

3.2

3.2

Mar. 10

3.2

Supplemental record.- Mar. 2, 5:30 p.m., 200 sec.-ft.

454720 O - 42 - 9
120 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Thompson Creek at flood-control reservoir near Claremont, Calif.

Location.- Staff gage, lat. 34°08'30", long. 117 0 42'30'', In S»i sec. 27, T. 1 N., R 8 

W., 3 miles north of Claremont. Altitude of stream bed, 1,58S feet.

Drainage area.- Area, 3.91 square miles. Average altitude, 2,670 feet. Maximum altltude, 4,700 fept. Average slope, 36 percent. Length of main'stream channel, 2.5 

miles. Average slope of main stream channel, 24 percent.

Qage-hfeight record.- Staff gage read at Irregular intervals except during storm period, 

when several observations were made daily.

Discharge record.- Computed from valve rating curves, valve operation record, record 

of stage, observations of depth of flow In release flume, and stage-capacity table; 

stage-capacity table based on survey of November 193S used throughout storm period.

Maxima.- 1938: Inflow, 669 second-feet 2:30 p.m. Mar. 2.

Outflow, 133 second-feet 12:30 p.m. Mar. 3. 

1932-37S Mean hourly Inflow, 91 second-feet between 8 and 9 a.m. Feb. 9, 1932.

Remarks.- Records good Feb. 28 to Mar. 6; major portion of Inflow for periods Feb. 1- 

27 and Mar. 7 to Apr. 30 diverted above dam to spreading grounds. Altitude of 

spillway, 1,640 feet. Area at spillway level,. 35 acres. Capacity at spillway 

level before storm of Mar. 2, 812 acre-feet; after storm, 786 acre-feet. Basic 

data Feb. 28 to Mar. 6 and entire record Feb. 1-27 and Mar. 7 to Apr. 30 furnished 

by Los Angeles County Flood Control District, through H. E. Hedger, chief engineer.

Mean dally inflow, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0

0

0

0

0

0

0

0

0

.1

Mar.

42

259

101

44

25

16

9

0

0

0

Apr.

0

0

0

0

0

0

0

0

0

0

Day

11

12

13

14

15

16

17

18

19

20

Feb.

1.0

5.2

4.8

0

0

.2

0

0

0

0

Mar.

3.4

14

11

5.5

1.8

0

0

0

0

0

Apr.

0

0

0

0

00 N

0

0

0

0

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

0

24

70

Mar.

0

0

0

0

0'0

0

0

0

0

0

17 2

1,050

Apr.

0

0

0

0

0

0

0

0

0

0

0

0

Inflow, in second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 87

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Feb. 28

0.2

.2

.2

.3

30

39

27

23

22

21

20

20

19

18

18

18

19

23

35

66

Mar. 1

170

155

117

75

51

43

40

37

35

32

29

27

25

22

18

16

15

14

14

13

12

12

11

12

Mar. 2

13

15

17

24

34

55

98

130

233

375

430

398

380

460

535

508

540

530

405

292

236

212

173

136

Mar. 3

126

119

120

153

142

132

126

120

115

108

102

96

92

88

84

80

77

75

74

73

71

70

69

67

Mar. 4

62

56

50

46

43

39

37

36

35

34

34

33

Mar. 5

29

26

23

2S

21

19

Mar. 6

16

Mar. 7

9

Supplemental record.- Mar. 2, 2:30 p.m., 669 sec.-ft.

Mean dally outflow, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

0

16

101

87

39

25

17

12

20

23

Apr.

1.7

1.7

1.7

1.7

1.6

1.6

1.6

1.6

1.6

1.6

Day

11

12

13

14

15

16

17

18

19

20

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

25

.5

3.1

10loll

13

13

12

12

Apr.

1.3

1.3

1.3

1.3

1.3

1.3

1.3

1.2

1.2

1.2

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

.1

.1

.1

.1

.1

.1

0

1.2

Mar.

5

1.2

1.2

1.7

1.8

1.7

2.2

2.3

2.1

2.0

2.1

938

Apr.

1.0

1.0

1.0

1.0

1.0

1.0

.9

.9

.9

.9

1 29

76.8
BASIC DISCHARGE RECORDS 121

Outflow, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

March 2

0

0

39

52

59

63

67

68

70

March 3

70

72

74

76

77

78

79

79

80

80

80

81

132

131

130

129

128

128

127

125

123

121

120

119

March 4

117

114

111

107

104

101

98

96

50

49

49

47

45

March 5

45

42

42

36

32

28

March 6

24

26

32

29

23

26

Supplemental record.- Mar. 3, 12:30 p.m., 133 sec.-ft.

Los Angeles River Basin

Pacoima Creek at flood-control reservoir near San Fernando, Calif.

Location.- Water-stage recorder, lat. 34°20'00n , long. 118023 1 45n , in HWilfflfj sec. 19, 

T. 3 N., R. 14 W., 4 miles northeast of San Fernando. Altitude of stream bed, 

1,650 feet.

V

Drainage area.- Area, 27.8 square miles. Average altitude, 3,890 feet. Maximum 

altitude, 6,500 feet. Average slope, 41 percent. Length of main stream channel, 

15.6 miles. Average slope of main stream channel, 5.2 percent.

Page-height record.- Water-stage recorder graph; staff-gage readings daily at 8 a.m. 

and more frequently during storm period.

Discharge record.- Computed from spillway rating curve, valve rating curves, valve 

operation record, record of stage and stage-capacity tables; stage-capacity table 

based on survey of January 1936 used to time of peak stage of Mar. 3 (1 a.m.}; 

table corrected by silt survey made after storm used thereafter.

Maxima.- 1938: Inflow, 8,450 second-feet 3:50 p.m. Mar. 2.

Outflow, 2,440 second-feet 12 p.m. Mar. 2 to 2 a.m. Mar. 3. 

1914, 1927-37: 5,400 second-feet February 1914.

Remarks.- Records good. Altitude of spillway, 1,950 feet. Area at spillway level, 63 

acres (after storm of Mar. 2). Capacity at spillway level before storm, 5,592 acrefeet; after storm, 5,004 acre-feet. Basic data Feb. 27 to Mar. 11 and entire record 

Feb. 1-26 and Mar. 12 to Apr. 30 furnished by lios Angeles County Flood Control District, through H. E. Hedger, chief engineer.

Mean daily inflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

14

14

100

113

55

32

24

20

24

30

Mar.

355

2,430

1,520

579

367

279

225

193

156

140

Apr.

60

55

53

47

45

44

42

39

39

37

Day

11

12

13

14

15

16

17

18

19

20

Feb.

198

146

84

61

49

42

38

35

35

30

Mar.

130

310

445

364 -

304

254

215

183

159

146

Apr.

36

34

36

35

34

33

32

31

29

28

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

27

25

24

21

21

21

26

116

,50.9

2,830

Mar.

132

119

106

96

67

78

74

71

66

62

61

313

19,250

Apr.

28

27

26

31

39

28

24

23

27

28

35.7

2,120
FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Inflow, in second-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

14

14

14

14

15

15

16

17

18

20

24

26

27

28

29

33 .

36

38

40

39

39

38

38

37

Feb. 28

37

37

37

42

54

51

47

54

82

95

106

119

141

140

135

131

129

128

130

136

169

270

300

412

Mar.l

435

590

690

685

500

390

375

364

350

336

371

306

289

275

262

253

250

249

248

247

246

244

242

247

Mar. 2

261

276

300

343

375

407

495

630

815

1,060

1,190

1,700

3,120

3,840

5,950

7,850

5,730

5,000

4,700

3,860

3,320

2,950

2,710

2,550

Mar. 3

2,480

2,370

2,220

2,100

2,000

1,880

1,800

1,690

1,600

1,540

1,500

1,450

1,380

1,320

1,260

1,180

1,140

1,070

1,030

1,000

960

920

890

860

Mar. 4

805

780

748

718

. 695

665

636

680

608

597

570

537

528

520

516

508

480

474

469

460

454

448

440

436

Mar. 5

415

377

360

348

329

314

liar. 6

305

293

270

260

259

259

Mar. 7

250

230

219

210

203

204

Mar. 8

207

200

195

190

178

170

Mar. 9

162

156

153

152

151

148

Mar. 10

146

142

140

138

135

131

Supplemental record.- Mar. 2, 3:50 p.m., 8,450 sec.-ft.

Mean daily outflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

56

618

1,740

676

416

330

293

316

310

304

Apr.

50

50

50

77

108 .

106

104

100

97

95

Day

11

12

13

14

15

16

17

18

19

20

Feb.

0

18

30

19

8

0

26

32

22

33

Mar.

297

243

296

301

240

304

302

297

292

285

Apr.

74

87

83

86

62

47

46

46

35

30

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

33

33

33

33

28

22

8

8

13.8

766

Mar.

265

268

249

144

106

120

91

76

61

57

49

303

18,650

Apr.

27

25

25

25

25

17

22

22

22

9.5

55.1

3,280

Outflow, in second-feet, at Indicated tine, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

20

20

20

20

20

20

20

20

20

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Feb. 28

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

25

25

25

25

25

25

25

25

Mar.l

25

25

25

25

25

25

25

25

25

25

25

25

25

25

25

50

75

75

75

75

174

174

174

174

Mar. 2

174

87

0

 o

0

0

0

0

0

0

0

0

0

143

297

487

684

796

1,480

2,220

2,380

2,410

2,420

2,440

Mar. 3

2,440

2,440

2,370

2,250

2,140

2,020

2,010

2,000

1,980

1,960

1,940

1,840

1,730

1,630

1,540

1,460

1,380

1,290

1,240

1,180

1,140

1,080

1,050

1,020

Mar. 4

958

987

887

847

817

787

747

726

706

686

666

646

606

576

545

525

505

485

Mar. 5

475

465

455

434

424

404

393

373

353

Mar. 6

342

332

325

321

321

320

Mar. 7

0

320

320

320

319

319

318

Mar. 8

317

317

316

315

314

313

Mar. 9

312

312

310

310

308

307

Mar. 10

306

305

304

303

302

300
BASIC DISCHARGE RECORDS 123

Tujunga Creek at flood-control reservoir near Sunland, Calif.

Location.- Water-stage recorder, lat. 34°17'30", long. 118°11 '10", in W$ seo. 1, T. 2 

N., R. 13 W., 1C miles northeast of Sunland. Altitude of stream bed, 2,104 feet.

Drainage area.- Area, 81.4 square miles. Average altitude, 4,500 feet. "Maximum altitude, 7,078 feet. Average slope, 40 percent. Length of main stream channel, 12 

miles. Average slope of main stream channel, 7.8 percent.

Page-height record.- Water-stage recorder graph except 2-6 p.m. Mar. 2} staff-gage 

readings daily at 8 a.m. and more frequently during storm period; maximum stage 

determined from floodmarks.

Discharge record.- Computed from record of stage, spillway rating curve, valve rating 

curves, valve operation record, discharge measurements, and stage-capacity tables; 

stage-capacity table of December 1935 used to tine of peak stage (5:20 p.m. Mar. 2), 

table corrected by silt survey made after storm used thereafter.

Maxima.- 1938: Inflow, 35,000 second-feet 5 p.m., Mar. 2.

Outflow, 32,500 second-feet 5:20 p.m., Mar. 2. 

1931-37: Mean hourly inflow, 2,430 second-feet 3 to 4 a.m., Jan. 1, 1934.

Remarks.- Records fair. Spillway discharge affected by debris Mar. 5-6. Altitude of 

spillway, 2,290 feet. Area at spillway level, 74.4 acres (after storm of Mar. 2). 

Storage capacity before storm, 6,240 acre-feet; after storm, 4,734 acre-feet. Basic 

data Feb. 27 to Mar. 11 and entire record for remainder of February, March, and 

April furnished by Los Angeles County Flood Control District, through H. £. Hedger, 

chief engineer.

Mean daily inflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

66

39

118

15C

66

34

25

25

59

91

Mar.

1,240

11,600

2,330

867

521

415

327

324

247

236

Apr.

112

117

115

108

102

82

82

84

82

82

Day

11

12

13

14

15

16

17

18

19

20

Feb.

532

228

112

81

65

51

39

37

55

43

Mar.

204

825

558

405

347

301

259

272

242

205

Apr.

84

85

91

81

80

78

73

72

67

66

Day

21

22

23

24

25

26

27

28

29

30

31

Inflow, in acre-feet. ........................................

Feb.

38

38

35

32

35

35

106

501

5,430

Mar.

199

188

184

171

166

143

133

142

135

126

117

46,470

Apr.

62

60

62

72

69

62

59

57

64

61

4,700

Inflow, in second-feet, at indicated time/ 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

15

24

33

40

40

38

35

32

30

36

48

57

66

82

102

131

173

229

275

253

244

238

221

200

Feb. 28

160

179

188

196

210

240

280

318

490

580

553

580

600

600

585

595

620

640

515

470

440

720

1,100

2,130

Mar.l

3,140

3,330

3,060

2,310

1,750

1,430

1,300

1,220

1,160

1,020

925

882

820

775

715

680

650

620

590

547

520

492

469

448

Mar. 2

420

420

437

655

805

1,000

1,450

2,200

3,280

4,300

7,400

13,000

18,700

23,100

25,000

30,000

35,000

28,500

23,200

18,300

14,900

11,600

9,550

7,860

Mar. 3

5,750

4,250

3,420

3,000

2,700

2,600

2,530

2,400

2,220

2,150

2,070

1,990

1,880

1,780

1,700

1,610

1,550

1,470

1,400

1,350

1,290

1,230

1,190

1,150

Mar. 4

1,090

1,030

970

920

875

857

815

773

746

723

700

675

Mar. 5

612

574

497

451

440

435

Mar. 6

431

428

422

411

392

366

Mar .7

327

Mar. 8

324

Mar. 9

247

liar. 10

236

Mean dally outflow, in second-feet, 19S8

Day

1

2

3

4

5

6

7

8

9

10

Feb..

13

21

7

2.5

40

45

45

45

0

0

Mar.

627

10,900

2,530

893

524

405

818

775

717

342

Apr.

100

109

111

108

137

155

155

104

68

69

Day

11

12

13

14

15

16

17

18

19

20

Feb.

13

55

76

76

57

26

50

31

38

57

Mar.

196

557

619

383

320

433

429

283

248

213

Apr.

71

72

73

74

50

18

18

8

2.7

0

Day

21

22

23

24

25

26

27

28

29

30

31

Outflow, in acre-feet ....... , ................................

Feb.

57

57

57

57

57

57

17

60

2,210

liar.

225

191

169

195

67

170

171

144

97

99

97

47,280

Apr.

0

0

0

0

0

0

0

0

0

31

3,040
124 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Outflow, in second-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

e

7

8

9

10

11

M

Feb. 27

52

52

52

52

52

52

52

26

0

0

0

0

0

0

0

0

0

0

Feb. 28

0

- 0

0

0

0

0

0

80

160

160

160

160

160

Har.l

518

518

518

518

560

584

571

571

530

530

520

507

507

507

480

456

430

712

994

990

990

985

985

980

Mar. 2

9 80

975

975

970

970

970

970

970

1,120

1,130

1,560

8,090

15,300

21,400

23,200

28,200

32,200

31,400

25,100

20,300

16,400

13,100

10,600

8,330

Mar. 3

6,620

5,200

3,070

3,150

2,800

2,630

2,590

2,520

2,410

2,220

2,130

2,060

1,960

1,870

1,780

1,690

1,600

1,520

1,480

1,410

1,360

1,310

1,260

1,210

KELP. 4

1,170

1,130

1,090

1,050

1,020

965

960

930

910

896

882

875

865

846

820

800

775

757

742

730

718

703

690

680

Mar. 5

650

625

600

585

570

515

470

445

431

420

413

408

Mar. 6

400

400

410

410

410

395

Mar. 7

375

365

360

360

370

380

1,510

1,460

1,100

1,080

Mar. 8

1,050

1,040

1,020

640

190

190

670

660

Mar. 9

655

646

635

625

940

930

905

Uar. 10

891

880

300

295

205

205

205

205

0

200

Supplemental record.- Mar. 2, 5:20 p.m., 32,500 sec.-ft.

Santa Anita Creek at flood-control reservoir near Sierra Madre, Calif.

Location.- Water-stage recorder, lat. 340 ll'10n , long. 118*01'10", near center of sec. 

10, T. IN., R. 11 W., 2^ miles northeast of Sierra Madre. Altitude of stream bed, 

1,100 feet.

Drainage area.- Area, 10.8 square miles. Average altitude, 3,560 feet. Maximum altitude, 5,886 feet. Average slope, 47 percent. Length of main stream channel, 4.2 

miles. Average slope of main stream channel, 20 percent.

Gage-height record.- Water-stage recorder graph to about 2 p.m. Mar. 2. Frequent

staff-gage readings during storm period; one reading dally at 8 a.m. at other times.

Discharge record.- Computed from record of stage, spillway discharge curves, valve 

rating curves, valve operation record, discharge measurements, and stage-capacity 

tables; stage-capacity table based on survey of February 1936 used to time of peak 

stage of Mar. 2 (4:20 p.m.), table based on survey of July 1938 used thereafter.

Maxima.- 1938: Inflow, 5,490 second-feet 4:10 p.m. Mar. 2.

Outflow, 5,260 second-feet 4:20 p.m. Mar. 2. 

1932-37: Mean daily inflow, 323 aeoond-feet Jan. 1, 1934.

Remarks.- Records good except those for Mar. 3 to Apr. 30, which are fair. Area at 

lower spillway level, 10.8 acres (July 1938). Oapaoity at lower spillway level 

before storm of Mar. 2, 1,010 acre-feet, after storm, 683 acre-feet. Altitude of 

spillway, 1,316 feet. Basic data Feb. 27 to Mar. 11 and entire record for rest of 

February, March, and April furnished by Los Angeles County Flood Control District, 

through H. E. Hedger, chief engineer.

Mean daily Inflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

18

7.5

74

74

29

17

14

11

21

19

Mar.

423

1,780

666

285

185

143

123

107

90

86

Apr.

36

34

32

30

28

27

27

27

27

26

Day

11

12

13

14

15

16

17

18

19

20

Feb.

64

50

32

25

19

16

15

16

17

13

Mar.

77

146

129

108

93

85

78

74

69

67

Apr.

26

26

26

26

26

26

25

24

24

24

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

11

11

10

10

9

8.5

15

332

 ZA O

1,900

Mar.

62

58

55

51

49

47

45

43

42

40

38

10,600

Apr.

24

23

23

23

23

22

21

21

20

20

25.6

1,520
BASIC DISCHARGE RECORDS

Inflow, In second-feet, at indicated time, 1938

Hr,

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

7

7.5

7.5

8

9

9.5

11

9.5

9

16

22

24

27

25

23

21

18

15

14

17

21

19

17

17

Feb. 28

17

21

30

51

96

115

147

226

239

258

330

405

505

505 479'

455

429

411

390

350

370

660

900

1,130

Mar.l

1,110

890

750

650

555

490

457

430

393

360

334

323

312

298

278

260

250

239

288

222

218

217

220

225

Mar. 2

231

240

260

285

370

402

450

820

970

1,650

2,130

2,010

2,600

3,060

4,130

5,120

4,700

3,500

2,600

2,000

1,700

1,500

1,390

1,300

Mar. 3

1,160

1,090

1,020

930

880

830

770

780

680

655

625

590

560

535

516

498

483

468

453

440

428

417

405

392

Mar. 4

370

350

327

302

285

274

261

249

240

234

229

223

Mar. 5

812

201

187

175

162

156

Mar. 6

150

146

143

140

138

134

Mar .7

131

129

125

117

115

115

Mar. 8

115

113

107

103

98

96

Mar. 9

95

93

90

88

86

86

Mar. 10

86

86

86

86

83

80

Supplemental record.- Mar. 2, 4:10 p.m., 5,490 sec.-ft.

Mean dally outflow, In second-feet, 1938

Day

1

2

3

 4

5

6

7

8

9

10

Feb.

 8

12

4.7

43

46

28

29

38

14

0

Mar.

559

1,520

692

292

188

146

124

107

90

86

Apr.

37

37

36

34

34

34

35

35

36

37

Day

11

12

13

14

15

16

17

18

19

20

Feb.

19

56

55

43

32

23

17

12

8.5

12

Mar.

77

144

130

109

93

85

79

74

70

67

Apr.

21

.3

1.1

19

26

26

25

24

24

24

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

11

11

11

11

11

11

, 13

104

24.4

1,360

Mar.

62

59

55

51

57

42

46

42

40

42

39

170

10,450

Apr.

24

24

23

22

23

22

21

21

20

21

1,520

Outflow, In second-feet, at Indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

H

Feb. 27

10

10

10

10

5

0

0

0

0

2£

Feb. 28

25

25

25

25

25

50

75

75

75

. 25 75

25

25

25

25

75

138

200

200

200

200

467

564

Mar.l

573

580

584

583

580

575

568

560

550

541

530

518

506

Mar. 2

494

484

477

367

256

263

402

548

570

983

2,450

3,850

5,060

4,960

3,320

2,790

1,950

1,760

1,610

1,520

1,350

Mar .3

1,230

1,130

1,060

980

930

870

807

745

705

665

645-

605

590

550

530

510

495

480

467

453

440

425

411

398

Mar. 4

383

370

359

346

336

325

318

310

302

297

290

280

269

260

260

260

258

254

250

246

241

236

231

226

Mar. 5

216

195

185

185

160

160

Mar. 6

155

148

144

140

137

133

Mar. 7

130

127

127

115

115

115

Mar. 8

115

115

105

105

98

97

Mar. 9

95

93

93

86

86

86

Mar. 10

86

86

86

86

86

82

Supplemental record.- Mar. 2, 4:20 p.m., 5,260 sec.-ft.
126 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Little Santa Anita Creek at flood-control reservoir near Sierra Madre, Calif.

Location.- Water-stage recorder, lat. 34°10 l 40n , long. 1180 02 l 40n , near center of sec. 

10, T. IN., R. 11 W., li miles northeast of Sierra Madre. Altitude of stream bed, 

1,110 feet.

Drainage area.- Area, 2.39 square miles. Average altitude, 3,170 feet. Maximum altitude, 5,433 feet. Average slope, 50 percent. Length of main stream channel, 3.0 

miles. Average slope of main stream channel, 2? percent.

Page-height record.- Water-stage recorder graph.

Discharge record.- Outflow obtained from record cf water-stage recorder located 270 

feet below the dam (operated by Los Angeles County Flood Control District). Inflow 

Feb. 1-27 and Mar. 4 to Apr. 30, taken as equal to measured outflow; inflow Feb. 

27 to Mar. 3 computed from measured outflow and changes in storage, based on record 

of stage and stage-capacity tables. Stage capacity table based on survey of April 

1932 used to 2 p.m. Mar. 2, and table based on survey made after 'storm used after 

12 p.m. Mar. 2; capacity loss distributed during period 2-12 p.m. Mar. 2.

Maxima.- 1938: Inflow, 633 second-feet 4:10 p.m. Mar. 2. 

Outflow, 630 second-feet 4:10 p.m. Mar. 2.

Remarks.- Records fair. Altitude of spillway, 1,172 feet. Area at spillway level, 

1.04 acres (April 1938). Capacity at spillway level before storm of Mar. 2, 47.4 

acre-feet, capacity after storm, 8.5 acre-feet. Basic data Feb. 28 to Mar. 3 and 

entire record Feb. 1-27 and Mar. 5 to Apr. 30 furnished by Los Angeles County 

Flood Control District, through H. E. Hedger, chief engineer.

Mean daily Inflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.9

0

6.5

8.5

3.9

1.8

1.1

.8

2.4

1.8

Mar.

67

214

118

48

38

32

28

16

12

16

Apr.

5.5

5

5

6

6

5.5

5

f7

o

5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

6.5

5.5

3.3

2.8

2.0

1.6

1.2

1.1

.9

.7

Mar.

19

38

35

20

30

14

12

13

19

24

Apr.

4.7

5

5.5

6

6

6

5

2.8

1.6

2.2

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0.7

.5

.4

.3

.2

.2

1.5

47

3.72

206

Mar.

27

16

8.5

8

11

11

7.5

7

7.5

4.7

4.7

1,840

Apr.

3.7

3.0

2.2

3.3

3.3

3.3

2.8

2.5

2.8

2.3

4.22

251

Inflow, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

February 27

0.2

.4

.4

.6

1.7

3.6

2.3

2.0

2.2

2.2

1.8

1.8

February 28

3.3

7

15

23

36

19

24

38

53

60 

73

92

76

65

58

54

58

77

103

125

134

March 1

133

132

123

105

92

85

80

75

72

66

62

57

53

48

44

41

39

36

34

33

33

34

35

38

March 2

40

45

49

56

65

92

76

80

143

220

236

212

252

370

465

560

403

363

318

272

247

230

214

198

March 3

180

164

151

138

126

112

100

86

79

76

73

70

Supplemental record.- Mar. 2, 4tlO p.m., 633 sec.-ft.
BASIC DISCHARGE RECORDS 127

Mean dally outflow, in second-feet, 1938

Day

1

2

5

4

5

6

7

8

9

10

Feb.

0.9

0

6.5

8.5

3.9

1.8

1.1

.8

2.4

1.8

Mar.

64

192

118

48

38

' 32

28

16

12

16

Apr.

5.5

5

5

6

6

5.5

5

4.7

5

5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

6.5

5.5

3.3

2.8

2.0

1.6

1.2

1.1

.9

.7

Mar.

19

38

35

20

30

14

12

13

19

24

Apr.

4.7

5

5.5

6

6

6

5

2.8

1.6

2 .2

Day

21

22

23

24

25

26

27

28

29

30

31

Outflow, In acre-feet. .......................................

Feb.

0.7

.5

.4

.3

.2

.2

1.5

45

203

Mar.

27

16

8.5

8

11

11

7.5

7

7.5

4.7

4.7

OQ O

1,800

Apr.

3.7

3.0

2.2

3.3

3.5

3.3

2.8

2.5

2.8

3.3

4.26

253

Outflow, In second-feet, at indicated time, 195§

Hour

1

2 »

3»

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

February 27

0.2

.4

.4

.6

1.7

3.6

2.3

2.0

2.2

2.2

1.8

1.8

February 28

3.3

7

15

32

20

35

64

54

82

86

80

59

55

53

54

56

86

114

128

March 1

108

136

117

101

94

88

80

73

67

62

59

55

52

50

47

44

39

34

29

27

26

31

37

42

March. 2

49

43

41

52

68

82

13

10

168

182

170

139

157

215

416

630

421

363

324

277

240

219

205

200

March 3

190

182

160

148

157

162

162

150

138

129

121

112

107

102

99

89

85

84

83

82

82

81

80

80

Supplemental record.- Mar. 2, 4:10 p.m., 630 sec.-ft. 

Eaton Creek at flood-control reservoir near Pasadena, Calif.

Location.- Water-stage recorder, lat. 34°10'05", long. 118°05'30", In Santa Anita 

grant, 2 miles northeast of Pasadena, Los Angeles County. Altitude of stream bed, 

840 feet.

Drainage area.- Area, 9.48 equare miles. Average altitude, 3,100 feet. Maximum altitude, 6,156 feet. Average slope, 52 percent. Length of main stream channel, 6 

miles. Average slope of main stream channel, 17 percent. '

Gage-height record.- Water-stage recorder; staff-gage observations made daily at 8 

a.m. and more frequently during storm period.

Discharge record.- Computed from spillway rating curve, valve rating curve, valve 

operation record, record of stage, and stage-capacity tables; stage-capacity table 

based on survey of November 1937 used to time of peak stage of Mar. 2 (4:45 p.m.)", 

and table corrected by silt survey made after storm used thereafter. Inflow Feb. 

1-26 and Mar. 28 to Apr. 30 taken from records of station "Eaton Creek near 

Pasadena", 1 mile upstream. Small outflows measured by weir.

Maxima.- 1 1938: Inflow, 3,340 second-feet 4:40 p.m. Mar. 2. 

Outflow, 2,800 second-feet 4:45 p.m. Mar. 2.

Remarks.- Records good except those for Feb. 1-26 and Mar. 28 to Apr. 30, which are 

fair. Altitude of spillway, 888 feet. Area at spillway level, 39 acres (after 

storm of Mar. 2). Capacity at spillway level before storm of Mar. 2, 940 acrefeet, after storm, 698 acre-feet. The City of Pasadena Water Department diverts 

water from Eaton Creek during periods of low flow. Basic data Feb. 27 to Mar. 27 

furnished by Los Angeles County Flood Control District, through H. E. Hedger, chief 

engineer.
FLOODS OP MARCH 1938 IK SOUTHERN CALIFORNIA

Mean daily inflow, in seoond-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

9

1.9

36

46

20

4.6

0

0

8.8

6.3

Mar.

161

882

300

126

82

64

57

52

42

39

Apr.

18

13

9

11

12

11

11

10

8

8.5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

45

40

20

11

7.5

6

12

5

5

3.0

Mar.

38

74

55

44

32

31

33

26

25

27

Apr.

9

14

12

10

8.5

8

7

6

6

7.5

Day

21

22

23

24

25

26

87

28

29

30

31

Feb.

2.0

2.0

2.0

S.O

2.0

4.0

8

155

921

Mar.

26

24

22

24

22

 19

20

23

22

18

17

78.2

4,810

Apr.

8

7

6

5.5

5

4.5

4.5

4.5

3.5

4.5

8.42

501

Inflow, in seoond-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

U

Feb. 27

0

1.5

3

3

3

3

3

3.5

5.5

9.5

14

13

12

9

5

8

12

13

13

13

13

13

13

13

Feb. 28

13

13

13

25

53

78

102

121

138

146

153

170

211

200

190

179

165

149

129

140

223

428

440

475

Mar.l

500

386

302

263

221

195

171

158

145

133

124

113

103

96

89

82

78

73

70

69

68

67

70

75

Mar. 2

84

93

106

140

182

252

296

370

695

990

1,090

1,050

1,320

1,610

1,900

2,300

2,280

1,610

1,200

1,050

845

720

645

567

Mar. 3

515

466

442

430

413

395

370

320

315

295

279

263

256

250

242

230

219

207

200

191

186

180

173

170

Mar. 4

162

153

146

138

128

120

116

110

106

102

98

96

Mar. 5

91

86

81

77

73

70

Mar. 6

68

65

63

62

60

60

Mar. 7

59

58

57

56

56

54

Mar. 8

54

54

53

51

49

47

Mar. 9

*

45

44

42

41

39

38

Mar. 10

38

39

40

40

39

39

Supplemental record.- Mar. 2, 4:40 p.m., 3,340 sec.-ft.

Mean daily outflow, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

191

694

295

144

129

128

87

58

61 

60

Apr.

0

0

5

4.1

2.2

2.2

11

23

23

23

Day

11

12

13

14

15

16

17

18

19

20

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

16

34

32

15

49

55

35

45

45

30

Apr.

9.5

4.3

19

16

15

5.5

4.3

4.0

3.5

2.4

Day

21

22

23

24

25

26

27

28

29

30

31

Outflow, in acre-feet ........................................

Feb.

0

0

0

0

0

0

0

6

11.9

Mar.

21

21

21

18

17

16

17

31

49

0

0

4,780

Apr.

2.9

4.0

3.5

2.3

2.3

.9

0

0

0

0

6.43

383

Outflow, in second-feet, at indicated time, 1938

Hr.

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

.4

5

6

7

8

9

10

11

M

Feb. 27

0

0

0

0

0

0

0

0

Feb. 2 8

0

0

0

0

0

0

0

0

59

60

146

Mar.l

235

237

237

237

235

235

232

231

120

120

120

120

170

169

167

Mar. 2

166

165

165

166

60

60

149

244

452

464

474

800

2,330

2,660

1,980

1,250

1,250

1,240

1,160

715

607

Mar. 3

517

517

430

430

430

324

325

325

325

325

324

305

202

203

203

204

204

204

203

Mar. 4

165

165

165

164

164

131

131

131

131

131

131

131

130

130

Mar. 5

130

129

129

128

127

128

Mar. 6

127

126

134

131

129

127

Mar. 7

125

124

123

56

58

58

58

Mar. 8

58

58

58

58

58

58

Mar. 9

57

57

0

0

29

58

114

114

111

Mar. 10

108

106

70

35

35

35

35

35

Supplemental record.- Mar. 2, 4:45 p.m., 2,800 sec.-ft.
BASIC DISCHARGE RECORDS 129

Oalleguas Creek Basin 

Honda Barranca at Berylwood Road, near Somis, Calif.

Location.- Water-stage recorder and weir control, lat. 34°r7 l 22n , long. 119°02'32n , in 

Los Posas grant, 3t miles northwest of Somis, Ventura County. Altitude, 562 feet.

Drainage area.- Area, 1.35 square miles. Average slope, 35 percent. 

Sage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation determined from broad-crested weir rating. 

Maximum.- 1938: Discharge, 256 second-feet 9:05 p.m. Feb. 2B. 

Remarks.- Records good. Records furnished by U. S. Soil Conservation Service. 

Mean daily discharge, in second-feet, 1938

Feb. 28 ....... 13

Mar. 1 ....... .6

2 ....... 24

3 ....... 7.2

Runoff Feb. 2B to Mar. 3, in acre-feet ... 89

Discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

B

9

10

11

M

February 28

0

0

.2

.9

14.5

9

5

3.1

1.9

1.1

.7

.4

.2

.1

0

0

0

.4

2.1

23

200

16

40

7.6

March 1

2.4

.6

.2

0

0

0

0

0

0

0

0

.1

.1

.1

.2

.2

.2

.3

.3

.4

.4

.7

2.2

6.4

March 2

15

14

23

70

35

45

25

15

30

26

35

45

18

64

19

13

13

13

13

13

13

13

13

13

March 3

13

13

13

40

14

14

14

14

19

13

1.5

.6

.3

.2

.1

0

0

0

0

0

0

0

0

0

Supplemental record.- Feb. 28, 9:05 p.m., 256 sec.-ft. 

Honda Barranca at Perkins Road, near Somis, Calif.

location.- Water-stage recorder and concrete weir control, lat. 34°16'05n , long. 119° 

02'55", in Los Posas grant, at Perkins road, 3 miles west of Somis, Ventura County. 

Altitude, 349 feet.

Drainage area.- Area, 2.86 square miles. Average slope, 27 percent. 

Qage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation determined from broad-crested weir rating. 

Maximum.- 1938: Discharge, 486 second-feet 9:20 p.m. Feb. 28. 

Remarks.- Records good. Records furnished by U. S-. Soil Conservation Service. 

Mean daily discharge, in second-feet, 1938

Feb. 28 ....... 26

Mar. 1 ....... 1.0

2 ....... 119

3 ....... 19.4

Runoff Feb.28 to Bar.3, in acre-feet .... 328
130 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Discharge, in second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

11

February 28

0

0

0

0

0

60

5

.7

.1

0

0

0

0

0

0

0

0

0

0

40

172

100

237

4

March 1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

5.5

37

March 2

50

50

37

160

230

350

210

110

241

163

210

330

110

190

210

57

51

34

8

4.9

7.0

7.0

7.5

11

March 3

17

22

23

250

50

24

9

36

30

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Supplemental record.- Feb. 28, 9:20 p.m., 486 sec.-ft.
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 

MAXIMUM INFLOW TO RESERVOIRS

131

As previously explained, for several reservoirs the records of stage 

and outflow were used in conjunction with the capacity tables to compute 

rates of inflow. For those reservoirs for which the differences In contents over periods of time constitute a material factor in the determination of 'inflow, the results will tend to be more reliable for long than 

for short periods. The differences in contents for very short periods of 

time may be subject to considerable inaccuracy or even be indeterminable, 

and therefore the method is not well suited to the determination of rates 

of 'inflow at any Instant or for any very short period.

During the period of maximum discharge the Inflow to reservoirs was 

not combated for any interval of less than 15 minutes. Therefore, further study was made in order to estimate the maximum or peak rates of Inflow as given in the preceding tables.

Records of instantaneous rates of discharge throughout the flood 

rise were determined at five stations, which are listed in table 12. 

These records are included, also, in the basic discharge records presented in the next preceding section. Table 12 gives, for each of these 

stations, the peak discharge rate (inches per hour for 1 minute), the 

maximum 5-, 10-, 15-, and 30-mlnute and 1-hour rates, and the percentage 

of excess of the peak rate above the maximum 5-, 10-, 15-, and 30-minute 

and 1-hour rates. The percentages of excess, as given in table 12, appear to have a tendency to increase as the discharge rates decrease.

Sable 12.- Mgytnppn rates of discharge for Indicated periods and excess of peak discharge 

(duration 1 minute) over those rates In San Dimas and Calleguas Creek Basins, March 2,

1938

Stream

Saq ^iPIP 3 Creek

Wolf skill Creek near

San Dimas

West Pork of San

Dimas Creek, near

San Dimas

Fern Canyon Watershed Ho. 3

Fern Canyon Watershed JTo. 2

Oalleguaa Greek

Honda Barranca at

Perkins Road, near

Somis

Drainage 

area

<sq.

mi.)

2.78

1*66

.084

.063

2.86

Maximum discharge 

(inches per hour)

1

min.

0.463

.620

.350

.710

.214

5

min.

0.451

.615

.346

.703

.211

10

min.

0.439

.609

.340

.698

.206

15

min.

0.424

.602

.334

.691

.203

30

min.

0.390

.574

.324

.671

.190

1

hour

0.379

.559

.314

.651

.166

Excess of peak 

(1 minute) over 

maximum discharge

(percent )

15

min.

9.2

3.0

4.8

2.7

5.4

30

min.

18.7

8.0

8.0

5.8

12.6

1

hour

22.2

10.9

11.5

9.1

28.9
132 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

In figure 17, the discharge rates for each of the stations are plotted against corresponding intervals of time, using logarithmic scales. 

For this purpose, the peak discharge is assumed to correspond to a time 

interval of 1 minute. The plottings have been extended to longer intervals than are given in table 12. Discharge rates have also been plotted 

on the figure for some of the reservoirs for which the maximum average 

rates of inflow are believed to be reliably determined for the shorter 

intervals of time.

In general, the ratios of the maximum mean discharge, for progressively shorter intervals of time, to the maximum 24-hour discharge have 

been found to increase with enough regularity to suggest that the trend

of these ratios could be utilized in estimating the peak inflow to the *

reservoirs. The foregoing rather fragmentary observations as to the relation between peak rates of flow and the average rates over selected 

periods of time have been useful in estimating the peak inflow.

With the exception of those for the Fern Canyon stations, none of 

the records in table 12 cover conditions in the zones of heaviest rainfall and thus may not reflect in all particulars the conditions of flow 

that prevailed with runoff from higher rainfall intensities. There is 

the possibility that none of the records in table 12 are necessarily applicable to the behavior of flow in some of the steep channels in which 

higher and relatively sharper peaks may have occurred. As pointed out in 

the preceding section, the peak discharge was made up of debris in an unknown but perhaps substantial amount.

Table 13 shows, for each of 14 drainage basins for which basic discharge records have been presented, its area, the peak discharge (estimated for most of the streams) and maximum 24-hour discharge in secondfeet per square mile, and the ratios of the peak discharge and maximum 

mean discharge for indicated periods to the .maximum 24-hour discharge.

Figure 18 shows these ratios graphically for several of the stations 

represented in table 13 and also the average ratios for the 14 stations 

plotted against the corresponding intervals of time.

These ratios reflect generally and in a composite way the factors 

affecting the concentration of flow in individual streams, such as amount 

and rate of precipitation, direction of storm travel, size and shape of 

drainage basin, slope of stream channel and general slope of basin, infiltration rate and retention capacity of basin, and vegetative cover. It 

is to' be inferred that the greater the difference in these factors in the
4.0

0.15

0.1 _______________________________________________________________________

1" 2 3 4 5 6 7 8 9 10 15 SO 35 30 40 50 1 

Minutes

Figure 17.- Maximum rates of runoff for periods of 1 minute to 16 hours in certain areas in San 
Table 13.- Ratio of maximum discharge for Indicated periods to maximum 24-hour discharge for cer

Baains

Stream

Santa Ana River Basin

Santiago Greek, inflow to Santiago Reservoir near

Villa Park

San Gabriel River Basin

West Fork of San Gabriel River, inflow to floodcontrol reservoir near Gamp Rincon

San Dlmas Creek, inflow to flood-control reservoir near San Dimas

Dalton Creek, inflow to flood-control reservoir

near Glendora

Thompson Creek, inflow to flood- control reservoir near Claremont

Sawpit Creek, inflow to flood-control reservoir

near Monrovia

Live Oak Creek, inflow to flood-control reservoir

near La Verne

Fern Canyon Watershed No. 3 near San Dimas

Fern Canyon Watershed No. 2 near San Dimas

Los Angeles River Basin

Tujunga Creek, inflow to flood-control reservoir

near Sunland

Facoima Creek, inflow to flood-control reservoir

near San Fernando

Santa Anita Creek, inflow to flood-control reservoir near Sierra Madre

Baton Creek, inflow to flood-control reservoir

near Pasadena

Little Santa Anita Creek, inflow to flood-control

reeervoir near Sierra Madre

Average

Drainage 

area 

(sq.mi. )

62.5

40.4

16.5

4.49

3.91

3.27

2.30

.084

.063

81.4

27.8

10.8

9.48

2.39

-

Maximum discharge 

(sec. -ft. per sq.mi.)

Peak

158

666

279

301

172

306

162

226

457

430

304

508

352

265

-

24 hour

80.3

222

106

103

73.9

123

67.3

71.0

153

154

112

184

102

104

-

Peak

1.96

*3.00

*2.63

#2.92

#2.32

#2.48

*2.41

3.18

2.99

*2.79

*2.71

*2.76

*3.45

*2.51

2.72

4 h

1.

2.

2.

2.

2.

2.

2.

2.

2.

2.

2.

2.

2.

2.

2.

*Bstimated.
3.5

3.0

2.5

2.0

1.5

1.0

Figure 18.- Ratio of maximum discharge for indicated period to maximum 24-h

Santa Ana, San Gabriel, and Los Angeles 

Tu

We

Fa

Th

Li

Fe

Av
136 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

several basins, the wider the variation In the magnitude of the ratios 

during the floods.

Although the estimates of maximum or peak Inflow to the reservoirs Is 

obtained by somewhat Indirect methods into which Individual judgment enters, It Is believed that the margin of protable error Is relatively small 

and that, In general, the results are acceptable for determinations of extremely high flood flows and materially more accurate than the results 

obtained for the floods of March 1938 at other places In this region.

STUDIES OF BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS

AND RAINFALL

For the region most severely affected by the storms and floods of 

March 1938, many rainfall records have been presented and discussed In 

earlier sections of this report. Also, available basic discharge records 

believed to be reliable, have been presented In the section Immediately 

preceding. For most of the stream basins covered by these records there 

are given, In tables to be Introduced hereafter, pertinent data regarding 

the area, channel slopes, form relations, and other characteristics that 

may be examined with regard to their Influence on the concentration of 

flood runoff. (See tables 14 and 15.)

The studies of the hydrologlc features relate, first, to volumes of 

rainfall and flood runoff expressed In depth In Inches over these areas, 

and second, to rates of rainfall and runoff. Since the flood proper was 

largely associated with the heavy rain that fell on March 2, the analyses 

of rates of rainfall and runoff have been confined to the rates for the 

maximum 24-hour period. The discussion of the precipitation and runoff 

on an areal basis relates to the entire storm and flood period.

The analyses of the runoff data on an areal basis are primarily of 

Interest In problems relating to the storage of water at or near the 

source either In reservoirs or by means of land-management or cultural 

practices whereby the natural retention capacity of the basins can be 

maintained. The analyses showing the extent to which the runoff was concentrated with respect to time, the relations between the maximum rates 

of rainfall and runoff, and the time Interval or "lag" between the occurrence of rain and Its appearance as stream flow are largely of interest 

in problems relating to the control and disposal of water after it has 

reached the stream channels. They are essential to the designing of 

spillways, bridge openings, bypasses, flood channels, and other engineering structures and flood-control devices.
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS

Baain characteristics

137

The word "basin" is used at many places in this report to mean only 

the area upstream from the gaging station at which the runoff is measured. 

Therefore, under this usage, in the consideration of runoff it means the 

entire basin of a given stream only if the gaging station discussed is 

near the mouth of the stream.

By means of suitable maps certain drainage basins hereinafter listed 

were divided areally into segments or groups of segments, the upper limit 

of the first segment being 1 mile upstream from the reference station 

(lowermost point in the basin), and the upper limit of each succeeding 

segment or group being 1 mile upstream from that of the segment or group 

preceding it, or, when it is reached, the watershed line of the basin. 

The division of a drainage area into segments is illustrated in figure 19, 

which represents Tujunga Creek above the flood-control dam.

Figure 19.- Tujunga Creek Basin, showing segments used in determining 

maximum concentration of area.

Figure 20 shows the distribution of the segments of the drainage basins in accordance with this method of subdivision. The influence that 

the shape of the basin may have had on the concentration of runoff may be 

considered by studying this figure. For example, Paooima Creek Basin, except for the segment 9 to 10 miles from the dam, has no segment or group 

of segments as shown equal in area to 10 percent of the total drainage basin. The basin of West Fork of San Gabriel River, which produced the 

greatest runoff to the square mile measured at the flood-control dams during the flood of March 1938, has no group of segments upstream from the 

dam with an area as great as 20 percent of the entire drainage basin.
138 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

50:

Live Oak Creek

20

10

Eaton Creek

10,

30

10

 H 30

10

20

10

20

10

Santa An: ta Creek

'/7771

Dalton Creek

7ZZL San Dim is Creek

West Pork of San Gabriel River

Tujung i Creek

>/;7777.

Pacoima Creek

2 4 6 6 10 12 14 i£ 

Distance, in miles, above flood-control dam

Figure 20.- Distribution of drainage area above flood-control dams in San Gabriel and 

Los Angeles River Basins,
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 139

However, the group of segments 6 to 8 miles upstream from the flood-control 

dam represents about 36 percent of the total drainage basin. Dalton Creek 

Basin shows a concentration of 37.9 percent of its area, or 1.7 square 

miles, within 2 to 3 miles of the dam. Table 14 shows the segment or 

group of segments, classified on the basis above described, that contains 

the maximum concentration of drainage area. For example, for Tujunga 

Creek the group of segments with the largest area (12.5 square miles) is 7 

to 8 miles upstream from the flood-control dam measured along natural 

water courses. The average distance from the dam of all the segments in 

the entire drainage basin is shown in the last column to be 7.24 miles.

Table 14.- Characteristics of distribution of area in drainage basins 

above certain flood-control dams in San Gabriel and Los" Angeles River

Basins

Stream

San Gabriel River Basin

West Fork of San Gabriel

River

San Dimas Creek

Dalton Creek

Thompson Creek

Sawpit Creek

Live Oak Creek

Los Angeles River Basin

Tujunga Creek

Pacoima Creek

Santa Anita Creek

Eaton Creek

Little Santa Anita Creek

Drainage

area

{ square

miles )

40.4

16.5

4.49

3.91

3.27

2.30

81.4

27.8 -

10.8

9.48

2.39

Maximum

concentration

of area in 

segment

1 mile wide

(square miles)

7.9

4.0

1.7

1.8

1.3

1.0

12.5

4.4

3.8

2.6

1.1

Distance, in miles,

from dam

To maximum 

concentration of

area

7-8

4-5

2-3

2-3

2-3

1-2

7-8

9-10

2-3

4-5

1-2

To center 

of total

drainage

area

4.92

3.65

1.86

2.27

1.78

1.63

7.24

7.45

2.41

3.44

1.41

The topographic characteristics of the drainage basins studied herein 

are shown in table 15. The areas of these basins range from 0.063 square 

mile, for Fern Canyon Watershed No. 2, to 81.4 square miles, for Tujunga 

Creek Basin. The land slopes of all the basins are steep; the two Fern 

Canyon Watersheds have the greatest slope 65 percent and Live Oak and 

Thompson Creek Basins have the smallest slope 36 percent. The average 

altitudes in these basins range between 2,000 and 5,000 feet. Excluding 

the small Fern Creek Watersheds, Tujunga Creek Basin has the highest 

average altitude.

The size of the contributing area, the slope of the land areas and 

stream channels, and the shape of the basin, inasmuch as they determine 

distances and time of travel of the flood waters, undoubtedly influence the 

period of concentration of the flood runoff. Brief study of the data given 

in tables 15 and 17 (see pp. 140 and 150) suggests that the concentration 

characteristics of the several basins listed may be related directly or
140 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Table 15.- Topographic characteristics of certain drainage basins above point of 

measurement in Santa Ana, San Gabriel, and Los Angeles River Basins

Basin

Santa Ana River Basin

Santiago Creek

^f¥\ Gabriel River Basin^

West Fork of San Gabriel

River

San Dimas Creek

Dalton Creek

Thompson Creek

Sawpit Creek

Live Oak Creek

Fern Canyon Watershed

No. 3

Fern Canyon Watershed

No. 2

Los Aneeles River Basin

rnjunga Creek

Facoima Creek

Santa Anita Creek

Eaton Creek

Little Santa Anita Creek

Area 

in

square 

miles

62.5

40.4

16.5

4.49

3.91

3.27

2.30

.084

.063

81.4

27.8

10.8

9.48

2.39

Altitude, in feet

Maximum

5,680

8,038

5,558

3,686

4,700

5,390

3,694

5,400

5,400

7,078

6,500

5,886

6,156

5,433

Mini680

2,140

1,350

1,565

1,582

1,228

1,430

4,500

4,500

2,104.

1,650

1,100

840

1,110

Average

2,120

4,290

3,130

2,590

2,670

2,960

2,220

5,000

5,000

4,500

3,890

3,560

3,100

3,170

Average 

slope 

(percent )

45

47

42

40

36

50

36

65

65

4041'

47

52

50

Length 

of main 

stream 

channel 

(miles)

13

8.5

6

3.5

2.5

3.1

2.75

.52

.41

12

15.6

4.2

6.0

3.0

Average 

slope 

of main 

stream 

channel 

(percent )

7.3

13

13

11

24

25

16

33

42

7.8

5.2

20

17

27

indirectly to the mean land slope. Other influences can perhaps be detected, and the basic data are here recorded for examination by other investigators. Nevertheless, for the floods of March 1938 the rainfall 

characteristics seem to have greatly influenced, and indeed to have dominated, the runoff characteristics.

Runoff characteristics

There were four distinct phases in the runoff resulting from the 

storm of February 27 to March 4, corresponding in many respects to the 

four phases of the storm as previously described. The first phase is associated with the rain that fell on February 27 and 28. On February 27 

there was generally very little stream flow, but beginning about noon 

February £8, the flow gradually increased and reached a minor peak near 

or shortly after midnight, following the higher rates of rainfall near 

the end of the 2-day period. The second runoff phase lasted from about 

1 a.m. to midnight March 1 when there was an almost complete cessation of 

rain and a gradual decrease in stream flow. The third runoff phase began 

during the early morning of March 2 and reached a climax generally between 2 and 5 p.m. on the same day, when most streams reached their maximum rates of discharge for the flood. Although the rain did not cease
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 141

until later, the discharge rates were generally lower after the early 

evening of March 2. The fourth runoff phase lasted from the time of the 

peak on March 2 through March 10.

For basins for which continuous observations of runoff are available 

throughout the flood, analyses have been made of hourly records of rainfall, runoff, and retention, or the difference between the accumulated 

rainfall and the runoff. These analyses have been used as a check on the 

accuracy of derivations of discharge made to complete records at streamflow measurement stations. They are presented herein for use by engineers and hydrologlsts Interested In flood runoff, especially under the 

physiographic and climatic conditions existing In southern California.

Graphs of hourly rainfall and runoff, In mean depth In Inches, In 

figures 21 and 22, and graphs of the accumulated precipitation, runoff, 

and retention, In figures 23 and 24, are presented for West Fork of San 

Gabriel River and Live Oak Creek Basins, the two drainage areas showing 

the widest range In these factors, for the period February 27 to March 5. 

In figures 23 and 24 the periods covered by the runoff phases are Indicated. The method of determining the rainfall In the basins Is described 

on page 151.

First phase, February 27 and 28

Table 16 shows the amount, In Inches, of accumulated rain that fell /

over the 13 basins during the first storm, before the accumulated runoff 

beginning at midnight on February 26 equaled 0.10 Inch, and the accumulated rainfall and runoff and the retention, or difference between the 

rainfall and runoff, at the time of the first peak, which occurred generally either shortly before or shortly after midnight February 28. With 

the exception of the basin of the West Fork of San Gabriel River there 

was an accumulated retention In each of the 13 basins of between 3 and 

4.8 Inches before there was an accumulated runoff of 0.10 Inch; the average retention for the 13 basins was about 3.9 Inches. This condition was 

reached toward noon on February 28, 24 hours or more after the beginning 

of the storm. Although the accumulated rain up to the time of the first 

peak averaged about 8.5 Inches, the total runoff averaged only 0.7 Inch, 

Indicating an average retention at that time of about 7.8 Inches. The 

duration of rainfall In the first storm at rates In excess of 0.02 Inch 

an hour was about 30 hours, and on this time basis there was an average 

Increase In retention In the basins of about 0.26 Inch an hour.
hour per Inches 

\\\\\

\\\\

HOUVH seet HI HHaranos 
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 143

anon aed
20

d pre< ipita;lori

February 27 February 28

Figure 23.- Accumulated precipitation, accumulated runoff, and retention, February 

at flood-control dam No. 2. 
2S.O

18.0

16.0

14.0

12.0

10.0

8.0

2.0

February 27 February 28 March 1 March 2 

Figure 24.- Accumulated precipitation, accumulated runoff, and retention February 27 
Table 16.- Runoff characteristics during flood of February-March 1938 for certain areas i

Stream

Sftfl fftbriel Hirer

West Fork of San

Gabriel Rirer,

inflow to floodcontrol reservoir Bo. Z near

Camp Blncon

San Dlmaa Creek,

Inflow to floodcontrol reservoir near San

Dlnas

Dalton Creek, laflow to floodcontrol reservoir, near

Glendora

Thompson Creek,

inflow to flooddontrol reservoir

near Olareraont

Sswplt Creek, Inflow to f loodoontrol reservoir near Monrovia

Lire Oak Creek,

Inflow to floodeontrol reservoir near La

Verne

Fern Canyon Watershed No. 3 near

Son Dims

Fern Canyon Watershed 16. 2 near

SanDinOB

First phase, February 27-88

Drainage 

area

(so.

ml.)

40.4

16.6

4.49

3.91

3.27

2.30

.084

.063

la ted rain 

before accumulated

runoff

equaled 

0.10 inofa

1.89

4.34

3.60

4.69

3.96

3.87

4.78

3.66

Accumulation, in 

inches, at time of 

peak

Bainfall

9.02

8.34

7.48

7.20

9.23

7.20

8.86

8.37

Bun 

off

1.23

.48

.63

.19

.62

.41

.36

1.22

Betentlon

7.79

7.86

6.85

7.01

8.61

6.79

8.50

7.15

Second phase, Haroh 1

Time of 

1st peak 

(end of

1st

phase)

1 a.m.

1 a.m.

1 a.m.

1 a.m.

1 a.m.

1 a.m.

1 a.m.

12 p.m.*

Runoff 

from 

time of 

peak to

12 p.m.

(inches)

1.16

.61

.64

.36

.85

.37

.34

.79

Arerage 

rate of 

runoff 

per hour

during

1st depletion

period 

(Inches)

0.050

.027

.028

.015

.037

.015

.016

.033

Third phase, Haroh 2

Accumulation, In inches

At 12p.m. March 1

Bainfall

9.38

8.54

7.66

7.43

9.58

7.43

9.18

9.18

off

2.39

1.09

1.27

.64

1.47

.78

.70

2.01

Retention

6.99

7.46

6.38

6.89

8.11

6.65

8.48

7.17

At tine of 24 p

fall

21.28

18.73

14.75

16.46

19.60

16.00

20.34

20.34

Runoff

6.87

3.31

2.85

2.12

4.00

2.46

1.91

4.64

BA*

Aet

tio

14.4

15.4

11.9

14.

16.

13.

18.

15.7
Iiftt AnrntM HI»M

Tajunga Oreek, Inflow to floodcontrol reservoir near

9onland

PMoima Oreek, inflow to floodoontrol reservoir near San

Fernando

Santa Anita Oreek,

inflow to floodcontrol reservoir near Sierra

Eaton Oreek, inflow to floodcontrol reservoir near

Pasadena

little Santa Anita

Oreek, inflow to

flood-control

reservoir .near

Sierra Madre

81.4

27.8

10.8

9.48

2.99

3.08

3.99

3.78

4.46

4.62

6.16

6.34

11.78

10.03

10.20

.39

.2?

1.39

.73

.75

6.77

6.07

10.42

9.90

9.45

2 a.m.

3 a.m.

12 p.m.«

1 a.m.

12 p.m.a

.46

.41

1.29

.54

1.04

.081

.020

.064

.028

.043

6.42

6.70

12.19

10.60

10.76

.85

.68

2.65

1.27

1.70

5.58

6.02

9.54

9.23

8.97

16.69

15.20

24.21

20.93

20.40

3.65

2.08

6.52

3.51

3.55

1

1

1

1

1

a Feb. 28. 
148 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Second phase, March 1

Table 16 shows the total retention in each basin at the time of the 

first peak, near or shortly after midnight February 28, the total runoff 

from the time of the peak until midnight March 1, and the average rate of 

runoff per hour. Since there was little rain on March 1, the latter i-o±, 

resents essentially the rate of depletion in the water that was retained

in the basin as ground or channel storage at the end of the first storm.

 

The contribution to the runoff from groundwater storage due to antecedent

rainfall was relatively inappreciable. This draining out on March 1, immediately following the first peak, averaged about 0.03 inch an hour over 

the several basins, or about a tenth of the average rate at which the retention accumulated.

Third phase, March 2

Rain of the second storm period started to fall at about 10 p.m. 

March 1 and continued until about midnight March 2, with the greatest intensity occurring near noon on March 2 and with fairly little intensity 

during the late afternoon and evening. All streams rose rapidly and 

reached maximum peaks generally between 2 and 5 p.m.

Table 16 shows the accumulated rainfall, the runoff, and the retention in inches at midnight on March 1, about the beginning of the second

* 

storm, and the accumulated rainfall, runoff, and retention at the peak of

the flood. In the period of about 16 hours between midnight of March 1 

and the peak on March 2, there was an average accumulation of about 10.0 

inches of rain, 2.3 inches of runoff, and 7.7 inches 6f retention, the 

increase in the retention being at an average rate of about 0.48 inch an 

hour, or 85 percent in excess of the average rate of increase during the 

longer but less intense first storm. The average retention at the time 

of the peak was 15 inches.

Fourth phase, 6 p.m. March 2 to midnight March 10

Generally by about 6 p.m. March 2 all streams had started to recede 

and there was a gradual decrease in flow until March 11, when additional 

rain increased the "flow. Table 16 shows the total accumulated rainfall, 

at 12 p.m. March 3, which includes essentially all the rain associated 

with the floods and a small amount that fell after the major peak stages 

on March 3 and that may have influenced the rate of recession; the total 

accumulated runoff through 12 p.m. March 3, which probably includes
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 149

essentially all water in channel and surface storage at the time of the 

peak; and the accumulated runoff at IS p.m. March 10. Since there was 

relatively little rain from March 4 to 10, the difference in accumulated 

runoff at the two indicated times represents essentially a draining out 

of ground water. The retention as shown in table 16 at a stated hour on 

each of four days, namely, 6 p.m. on March 2 and midnight on March 3, 5, 

and 10, was not corrected for the evaporation and transpiration losses 

which may have occurred during the time intervals involved or for the 

rainfall from March 4 to 10. ' The results approximate the addition to 

basin storage because of the March storm. Table 16 shows also the average rates of runoff during three parts of the depletion period, namely, 

the 30-hour period from 6 p.m. March 2 to midnight March 3, the S-day 

period of March 4 and 5, and the 5-day period of March 6 to 10. It may 

be noted that there was a marked decrease in the average rates of depletion in the three periods.

Relation between rates of precipitation and rates of runoff

The greatest rise of the floods of March 1938 occurred on March 2 

and resulted from the rains that fell on the same day. It has been shown 

previously (fig. 14) that during the maximum 24 hours of rainfall, for 

periods of maximum rates of precipitation in progressively decreasing intervals of time, each succeeding period generally fell within the next 

longer period. Flood rises as shown on discharge hydrographs tend generally to have the same characteristic, and this is particularly true for 

the floods of March 1938, as will be illustrated hereafter. This tendency 

suggested a study of the relation of the maximum rates of precipitation 

to the maximum rates of runoff for corresponding intervals of time for 

drainage basins for which there are basic discharge records. Table 17 is 

a compilation of maximum rates of rainfall and runoff for 14 drainage 

basins for selected intervals of time ranging from 15 minutes to 24 hours 

each.

The average precipitation in the drainage basins was determined from 

the isohyetal map of the area for the total storm period February 27 to 

March 4. It was then distributed as to time on the basis of the records 

at a selected recording gage or gages. The rates of precipitation at the 

recording gages are summarized in table 2.
Table 17.- Ifarlnaim rates of rainfall and runoff, in inches per hour for given period* of. 1HB> for pertain a

Stream Basin

Santa Ana River Basin

Santiago Oreek, inflow to Santiago Beservoir near Villa Park

SfMl Pftbifl?1 Blvav B&aln

West for*, of San Gabriel Biver, inflow to flood-control reservoir near Camp Binoon

San Dimes Oreek, inflow to flood-control reservoir near San

Dimas

Dalton Oreek, inflow to flood-oontrol reservoir near Olendora

Thompson Oreek, inflow to flood-oontrol reservoir near Olaremont

Sawpit Oreek, inflow to flood-oontrol reservoir near Monrovia

Live Oak Oreek, inflow to flood-oontrol reservoir near La Verne

Fern Oanyon Watershed Bo. 3 near San Dimas

fern Canyon Watershed Bo. 2 near San Dimas

ftflfl ADR?!?8 Blvev BajilTi

Xnjunga Oreek, inflow to flood-oontrol reservoir near Sunland

Paoolma Oreek, inflow to flood-oontrol reservoir near San

Fernando

Santa Anita Oreek, inflow' to flood-oontrol reservoir near

Sierra Madre

Baton Creek, inflow to flood-oontrol reservoir near Pasadena

Little Santa Anita Oreek, inflow to flood-oontrol reservoir

near Sierra Madre

Drainage 

area 

(set .mi.)

62.5

40.4

16.5

4.49

3.91

3.27

2.30

.084

.063

81.4

*7.8

10.8

9.48

2.39

Per

15 minutes

Bainfall

1.63

2.46

2.60 *

2.00

1.84

1.69

1.76

1.62

1.62

2.09

1.74

1.85

2.24

1.96

Sunoff

0.243

*.98

.41

.47

*.26

*.49

.23

.39

.69

 .68

.49

.76

.63

 .39

30 minutes

Bainfall

1.35

1.78

1.79

.53

.23

.39

.17

.53

1.53

1.71

1.36

1.56

1.43

1.54

SunOff

0.241

.96

.40

.46

 .24

.47

.23

.32

.67

.62

.44

.74

.47

.37

1 hour

Bainfall

0.90

1.56

1.26

1.18

1.13

1.12

1.07

1.48

1.48

1.48

1*11

1.28

1.10

1.30

Bun 

off

0.237

.93

.39

.41

.23

.44

.23

.31

.65

.62

.43

.73

.43

.36

2 h

Bain

fall

0.80

1.41

1.16

1.00

1.00

1.03

.96

1.44

1.44

1.22

.92

1.20

1.00

1.16

 Estimated.
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 151

The assumption that the average rates of precipitation over a drainage basin will vary as do the rates at a nearby recording gage or else 

those obtained by averaging the rates for two or more nearby gages has 

certain inherent features that would seem to make it more reliable for 

the longer than for the shorter intervals for which rates are determined. 

The precipitation appears to have been extraordinarily uniform over the 

entire area, and the drainage basins are small in relation to the velocity of the storm; consequently, the rates for the basins may be accepted 

as quite reliable for the longer intervals of time. Obviously, however, 

there may be a question as to whether the uniformity of precipitation for 

short intervals of time, such as 1 hour or less, is such that the average 

rates over a basin will be closely related, either as to intensity or as 

to time of occurrence, to the rates obtained at one or more recording 

stations in the basin or within a few miles of it.

The runoff records for the West Fork of San Gabriel River at floodcontrol dam No. 2 and for Live Oak Creek, as presented in the basic discharge records, are typical of the extremes of flood discharge as determined from the reservoir records.

In figure 25 the rates of precipitation and runoff for both the West 

Pork of San Gabriel River and Live Oak Creek Basins are plotted to logarithmic scales against the durations of these respective rates. For this 

plotting, the data in table 19 have been supplemented to obtain additional 

points in these basins, and rates of precipitation have been computed to 

the maximum 5-minute interval.

The major part of the drainage of the West Fork of San Gabriel River 

was within the zone of heaviest rainfall during the storm of March 1938, 

and characteristics of its rainfall are included among those shown for 

the group B stations on figures 11 to 15. From the isohyetal map (pi. 17) 

the average rainfall on this drainage area of 40.4 square miles was found 

to be 23.62 inches for the period of the storm. The distribution of the 

rainfall was based on the records at Opid's camp, Crystal Lake, and San 

Gabriel flood-control dam No. 2.

Live. Oak Creek Basin, on the coastal side of the first divide, had 

somewhat less rainfall than the basin of the West Fork of San Gabriel 

River and averaged 17.41 inches over the 2.30 square miles. The rainfall 

intensities for this basin were distributed on the basis of the automatic 

record at the mouth of San Antonio Canyon, about 4 miles to the northeast, 

at an altitude a little above the average for Live Oak Creek Basin. The

454780 O - 42 - 11
152 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

record from the San Antonio Canyon gage seems to put that station in 

group C (figs. 11 to 15).

Similarly, figure 26 shows the maximum rates of precipitation and 

runoff for periods of 5 minutes to 24 hours for San Dimas Creek and Pern 

Canyon Watersheds Nos. 2 and 3, which are within the basin of San Dimas 

Creek. This basin has an area of 16.5 square miles, and in it are 174 

standard and 10 recording rain gages maintained by the United States Forest Service. The average precipitation over the basin during the storm 

was 20.71 inches, which was distributed on the basis of the recording 

rain gage at Tanbark Flats. The record at Tanbark Flats (altitude, 2,700 

feet) puts this station in group C.

The rainfall record in Fern Canyon (altitude, 4,800 feet), also in 

the drainage basin of San Dimas Creek, seems to conform to the records of 

the group B stations. The drainage basin of San Dimas Creek has a mean 

altitude of about 3,130 feet, with maximum and minimum altitudes of about 

5,600 and 1,400 feet, respectively. Evidently much of the rainfall in 

the basin would have followed more closely the Fern Canyon type of distribution than that shown by the Tanbark Flats station. The altitude of 

the latter station is nearer the mean altitude of the drainage area and 

so may represent the distribution of precipitation rates over the entire 

basin more accurately than the Fern Canyon station.

The rainfall over Fern Canyon Watersheds Nos. 2 and 3 was practically 

identical as determined by observations at 93 rain gages within these two 

drainage areas. The rainfall was analyzed on the basis of the Fern Canyon recording gage record.

It may be observed in the graphs for the five basins shown in figures 

25 and 26 that under the method of plotting used, for time intervals of 1 

hour or more the precipitation and runoff graphs for the respective basins 

are approximately parallel.

Graphs showing the runoff rates for Fern Canyon Watersheds Nos. 2 

and 3 indicate marked differences in the characteristics of these two 

drainage basins. These differences seem to result in part from the differences in their geology. That part of the mountains in which the Fern

Canyon Watersheds are situated is underlain by a metamorphic-igneous bed14 rock complex, the San Gabriel formation of Miller. Schists and

14 Miller, W. J., Geology of western San Gabriel Mountains: Univ. 

Calif, at Los Angeles, Pubs, in Math, and Phys. Sciences, vol. 1, no. 1, 

pp. 50-51, 1934.
.3.0

l] Ita1:lor , les ; ork of San Gabriel F Iv

1.0

o.g

0.8 

0.7 

0.6 

0.5

0.4 

0.3

0.2 

0.15

0.1

0.05 0.10 0.15 0.2 0.3 0.4 0.5 0.6 0.8 1 

Figure 25.- Maximum rates of precipitation and runoff, for

2 2.5 

Hours 

periods of 5 minutes to 24 hours, in b
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 155

granitic gneisses predominate and are intruded by many pegmatite and aplite dikes. The dikes, though locally crosscutting, generally follow 

schistosity planes in the metamorphic country rock for long distances. 

As a result of these conditions, the bedrock is characterized by a very 

prominent, steeply inclined planar structure of consistent orientation 

throughout the area.

In a report on a geologic examination ^ of the area after the 1938 

flood it is indicated that watershed No. 3, although larger than No. 2, 

has always had less runoff, both for seasons and for individual floods. 

In watershed No. 3 the planar structure of the bedrock lies normal to the 

drainage axis and dips fairly steeply downstream. This permits a more 

rapid percolation of water than in watershed No. 2, which is so oriented 

that the schistosity planes of the same rock types intersect its drainage 

axis at an acute angle, with correspondingly less opportunity for percolation and more opportunity for runoff to reach the stream channel.

The relation between maximum rates of precipitation and runoff for 

intervals of 24 hours and less is shown on figure 27 for five representative basins, namely, Live Oak, San Dimas, and Santa Anita Creek Basins, 

West Fork of San Gabriel River Basin, and Pern Canyon Watershed No. 2. 

The data used in the plotting are those shown in table 19, supplemented 

by other data for better definition of the relation. The number noted 

against a plotted point indicates the length of the interval in hours applicable thereto.

The decided break in some of these curves for intervals longer than 

about 12 hours is due to the falling off of the rates of rainfall for 

these longer intervals as compared to the rates of runoff, the runoff reflecting in this way the influence of ground-water seepage in the basin. 

This relation indicates that the rates of runoff corresponding to a fixed 

rate of rainfall have a tendency to increase as the durations of such 

rates increase. This tendency is demonstrated by table 18, in which are 

compiled data taken from figure 27. For example, for an average rate of 

precipitation of 1.0 inch an hour, lasting for 1.5 hours, on Live Oak 

Creek, the resulting average runoff was 0.22 inch an hour, and for the 

same average precipitation lasting for 4 hours on San sDimas Creek, the resulting runoff was 0.38 inch an hour. The corresponding figures increase 

progressively to 9.7 hours and 0.59 inch on the West Fork of San Gabriel

15 Storey, H. C., The'Fern watersheds, characteristic runoff differences: Mem. Rept. California Forest and Range Exp. Sta., San Dimas 

Exp. Forest, Sept. 19, 1939.
Precipitation,In Inches per h

H-Cf

< vfd 

o>W «i

>* H-O 

O O 

tDB> » » 

B> I-"O 

01 H.
Table 18*- Duration, la boors, and. rates of runoff, in laches per boor, for siren rates 

Gabriel and Los Angeles River Basins

Station

San Qabriel River Basin

West Fork of San Qabriel River, inflow to flood-control reservoir near Camp

Rincon

Son Dimas Oreek, inflow to flood-control reservoir near. San Dimas

Live Oak Creek, inflow to flood-control reservoir near La Verne

Fern Oanyon Watershed Bo. 2 near San Dimas

Los Angeles River Basin

Santa Anita Creek, inflow to flood-oontrol reservoir near Sierra Kadre

Rat

1.8

Duration

0.60

.5

.13

-

Run.

off

0.96

.40

_

.70

-

1.6

Duration

0.83

.63

_

.3

.42

HOH 

off

0.94

.39

_

.68

.74

Dur

tio

2.1

.8

-

2.2

.7

Table 19.- Ratios of maximum rates of precipitation and runoff for given periods to those for the maximum 

Stream

West fork of San Gabriel River, Inflow to flood-control reservoir near Caiqp Rineon

San Dimas Greek, inflow to flood-control reservoir near

San Dimas

Live Oak Creek, inflow to flood-control reservoir near

La Verne

Fern Oanyon Watershed Bo. 3 near San Dimas

Fern Qanyon Watershed Ho. 2 near San Dimas

15 minutes

Precipitation

4.46

5.70

4.30

3.02

3.03

RunOff

*2.88

2.56

*2.26

3. 04

2.91

30 minutes

Precipitation

3.24

4.16

2.86

2.83

2.83

Runoff

2.82

2.50

2.21

2.94

2.83

1 hour

Precipitation

2.82

2.86

2.61

2.74

2.74

Runoff

2.74

2.44

2.17

2.85

2.74

2 

Preci

itati

2.57

2.64

2.34

2.67

2.67

 Estimated.
158 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

River. A like tendency is shown for parts of the curves representing 

rates for 18 to 24 hours. A study of the rates of rainfall and runoff 

for 24 hours, as given in the last two columns of table 17, discloses a 

rough relation between such rates, which may be used in estimating runoff from drainage basins for which only rainfall records were available.

For further illustration of the relation between precipitation and 

runoff the data of table 19 have been plotted in three groups, as in 

figures 28 to 30, in general accordance with the magnitude of the rates 

of runoff prevalent in the basins.

These graphs illustrate further the similarity in the intensityduration relations for precipitation and runoff. The tendency of these 

curves to conform to straight lines drawn from the origin through the 

plotted points marks characteristics of the data that tended to produce 

parallelism in the logarithmic plotting of the relation as previously 

noted.

Table 19 shows, for the drainage basins analyzed in figures 25 and 

26, the ratios to the maximum rates of precipitation and runoff for a 24- 

hour period of the maximum rates for selected shorter periods. It may be 

noted that, for the listed basins, the runoff ratio for the 1-hour period 

varies from the precipitation ratio by +4 to -17 percent. The table illustrates the similarity in the intensity-duration relation of precipitation and runoff for the several basins, such similarity being fundamentally the same as that referred to In the preceding paragraph as tending 

to produce parallel lines under logarithmic plotting.

The foregoing graphic and tabular analyses indicate that for periods 

of time shorter than 1 hour the rainfall rates seem to increase more 

sharply than the runoff rates. For example, table 19 shows that on San 

Dimas Creek, for the 1-hour and half-hour periods, respectively, the precipitation ratio changed from 2.86 to 4.16, whereas the runoff ratio 

changed from 2.44 to 2.50. This difference is explainable in part by the 

fact that surface detention and channel storage in the stream system tend 

to modulate the reflection of high rates of rainfall for short intervals 

into high rates of runoff for corresponding intervals. It is important 

in these analyses not to overlook the fact that the computed discharge, 

particularly the highest discharge, includes debris, which is a complicating factor of unknown but probably substantial amount.
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS

2.8

2.4

0.2

0.1 0.3 0.4 0.5 

Runoff, in inches per hour

0.8

Figure 28.- Relation between maximum rates of precipitation and maximum rates of runoff 

during indicated periods of time for lowest rates of runoff.
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

0.2 0.3 0.4 0.5 

Runoff, in inches per hour

0.7 0.8

Figure 29.- Relation between maximum rates of precipitation and maximum rates of runoff 

during indicated periods of time for intermediate rates of runoff.
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 161

0.3 0.4 0.5 

Runoff, in inches per hour

0.8

Figure 30.- Relation between maximum rates of precipitation and maximum rates of runoff 

during indicated period of time for highest rates of runoff.
162 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

The difference may be due also, in part, to the fact that the rainfall rates over a given basin are estimated on the basis of the average 

rates at one, or at the most, only a few recording rain gages, located in 

or near that basin,*which method of procedure,, as has previously been 

noted, may tend to make the computed rainfall rates less reliable for intervals of 1 hour or less.

Lag between precipitation and runoff

The systematic relations found between rates of precipitation and 

rates of runoff suggest a comparison, between different drainage areas, 

of the times of their occurrence similar to the-comparison, furnished by 

figure 14, of the times of occurrence of maximum rates of precipitation. 

Figure 31 furnishes a comparison of the times of occurrence of maximum 

rates of precipitation and runoff in West Fork of San Gabriel River and 

Little Santa Anita Creek Basins and Fern Canyon Watershed No. 2.

The graphs representing runoff rates define periods of time which 

without exception are subsequent to those for the corresponding rainfall 

rates. The Interval between the times corresponding to the centers of 

mass of the rainfall and runoff occurring in comparable periods, such as 

1 hour or 2 hours, is denoted "lag". This term, as commonly used, is the 

time-difference in phase between salient features of rainfall and associated runoff. Table 20 shows, for the above-mentioned three basins and 

for Santa Anita Creek Basin, the time of occurrence of the center of mass 

of precipitation, of the center of mass of runoff, and of the lag as determined therefrom for selected periods ranging from 5 minutes to 24 

hours each.

In Fern Canyon Watershed No. 2, the lag in time of occurrence between the rainfall and the associated runoff appears to be generally from 

14 to 3 hours for periods of 12 hours and less, which seems to be rather 

excessive for a drainage area of only 0.063 square mile with.a maximum 

distance of water travel of about 0.4 mile from the divide to the gaging 

station. This apparently excessive lag tends to support the conciliaion 

that much of the runoff moved through subterranean channels, with the result that the flow was slower than the flow in surface channels and may 

have been subjected to the influence of ground-water storage. The indicated lag may have been due In part to the peculiarities of rainfall distribution. The rainfall involved In this comparison continued until about 

6 p.m. March 2, when it stopped almost completely as Indicated by the 

mass curves on figures 9 and 13.
Precipitation, Opid's 

camp and San Gabriel 

River dam No. 2

ecipitation Runoff 

a 5 \

\

10

11

\

4 6 8 10 12 m. 2 4 6

March 2, 1938 

West Pork of San Oabriel River

8 10 12m. 2 4 6

March 2, 1938 

Little Santa Anita Creek8 10 

Figure 31.- Time of occurrence of maximum periods of precipitation and runoff for basins of West 

and Fern Canyon Watershed No. 2.
lable 20.- Time of occurrence of center of mass of precipitation, center of mass of runoff, aai la

San Gabriel aai Los lageles Elver Basins

Stations

San Gabriel River Basin

West Fork of San Gabriel Elver 

Precipitation a/ 

Banoff 

Lag (in minutes)

Fern Canyon Watershed Bo. 2 

Precipitation V 

Banoff 

Lag (in minutes)

TrtJS jtantl?8 Elver Basin

Santa Anita Creek 

Precipitation £/ 

Banoff 

Lag (in minutes)

Little Sanjta Anita Creek 

Precipitation a/ 

Banoff 

Lag (in minutes)

IfaTlmnm per

Minutes

5

-

1.37pra 

4.00pm 

143

-

10

-

1.36pm 

4.02pm 

146

-

15

-

1.33pm 

4:01pm 

148

-

20

-

1.31pm 

4:01pm 

150

5.30pm 

4.10pm 

40

3. 30pm

30

1148pm 

4.15pm 

147

1.27pm 

4:01pm 

154

5<35pm 

4.15pm 

40

3.35pm 

4.15pm 

40

1

4.01pm 

146

1.38pm 

4.13pm 

155

3.36pm 

4«30pra 

54

3.36pm 

4.03pm 

27

2

1.00pm 

4.01pm 

181

1.58pm 

4.02pm 

124

3.04pm 

4i02pm 

58

3:04pm 

4:02pra 

58

3

12.40pm 

3.35pm 

176

1.34pm 

4.02pm 

148

3.28pm 

4il5pm 

47

3.28pm 

4.25pm 

57

1.0

3.3

15

1.5

4:0

12

3.

4.0

5

3.

3:

5

a Based on records for Opld's camp and San Gabriel Elver flood-oontrol dam Ho. 

b Based on record for San Dlmas Experimental Forest, Fern Canyon station, 

o Based on record for Hoegee's camp station.
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 165

Between 5t50 and 4 p.m. March 2, there was a sharp shower, direct 

surface runoff from which may have synchronized with the outflow from 

ground water from antecedent precipitation discharging Into the channel 

and so have produced the maximum discharge at the gaging station.

The lag on the West Fork of San Gabriel River appears to vary between 2 and 3 hours for periods of 6 hours and less. For longer periods 

than the maximum 6 hours, the lag Increases progressively to about 5 hours 

for the maximum 24-hour period, which probably indicates a greater influence of basin storage on the discharge.

Table 14 gives the travel distance from the center of the drainage 

area of the West Fork of Saft Gabriel River to the point of measurement as 

4.92 miles. If it is assumed that this represents the average travel distance for each particle of water In runoff, and that the lag represents tihe 

average travel time, for the maximum period of 30 minutes, this travel 

time would have been 147 minutes, which represents a mean velocity of 

2.95 feet a second. Mean velocities of similar magnitude may be determined for other maximum periods. Such velocities seem rather low for the 

average drainage basin slope of 47 percent. It Is believed that these 

apparently low rates of travel may be due to the passage of many of the 

particles of water through the underlying rock formations, and to the 

slower passage of others as surface runoff d"own minute channels on the 

mountain slopes before joining the larger tributaries.

It is probable that the peak discharge of the West Fork of San Gabriel River was caused in part by a heavy, short shower just before 4 p.m., 

the direct surface runoff from which combined with a large contribution 

of ground-water seepage. It seems likely that this sharp shower would 

have influenced the lag less for the longer periods.

On Santa Anita Creek, for which the center of the drainage area Is. 

about 2.41 miles from the gaging station, the lag for the maximum 30- 

minute period was 40 minutes. On assumptions similar to those previously 

made, the time of travel of the particles from the time of their precipitation to the time they passed the point of measurement would Indicate a 

velocity of 5.3 feet per second. On Little Santa Anita Creek the lag of 

40 minutes for the maximum 30-minute period would indicate a velocity of 

3.1 feet per second, which is comparable with the velocity indicated for 

the West Fork of San Gabriel River. In both the Santa Anita and Little 

Santa Anita Creek Basins, the maximum runoff was caused by the sharp 

shower which occurred between 3 and 4 p.m., and produced the maximum 

rates of rainfall for the storm period (see group B, Hoegee's camp, fig. 

15).
166 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The lag between rainfall and runoff ia a manifestation of the retardIng effect of the topographic and geologic characteristics of the basin . 

such as slope of the streams, roughness of channels, and vegetation 

cover on the time required for rainfall to become runoff. Observations 

seem to indicate that the greater the lag the less close will be the relation between rates of rainfall and runoff for the shorter periods of 

time, and the less responsive in increase will the stream flow be to the 

rainfall. Moreover, as previously pointed out, the lag as determined may 

embody conditions with respect to the distribution of rainfall and the 

concentration of runoff, which were peculiar to the storm and floods of 

March 1938.

Infiltration

It is shown elsewhere in this report (see tables 16 and 26) that the 

quantities of water retained In surface and ground storage during the 

floods of March 1938 In southern California were exceptionally large. 

The high rates of retention are attributed in large part to the high 

rates of infiltration that have been found to prevail during flood periods throughout much of the mountain area In Los Angeles and San Bernardlno 

Counties. Some interesting information concerning the characteristics of 

Infiltration Is available from data collected in the course of experiments 

by the United States Forest Service In the San Dimas Experimental Forest. 

Measurements of precipitation and direct surface runoff during the storm 

of March 1938 on experimental plots, each a fortieth of an acre in area, 

indicate extremely low rates of direct surface runoff or, conversely, extremely high rates of infiltration. The records of precipitation and 

runoff from three of a group of nine adjacent plots of the Fern Canyon 

series, showing greatest, medium, and lowest runoff, are shown in table 

21.

The plots are at an altitude of about 5,000 feet and have a slope of 

about 60 percent, which makes them comparable with areas at the headwaters of most of the streams in the San Gabriel and San Bernardino Mountains that are subject to excessive floods. They are comparable, also, 

in geology, slope, and vegetative cover, with many of the headwater areas 

in other'basins. The soil mantle on the plots is about 1 foot deep and 

overlies badly fractured bedrock. They have a fairly heavy and uniform 

growth of chaparral. Variations in soil mantle and the underlying rock 

structure, in addition to general tendencies toward inherent plot variability, are undoubtedly the cause of the main differences in the observed
BASIC DISCHARGE RECORDS IN RELATION TO BASIN CHARACTERISTICS 167

Table -81.- Precipitation and runoff for given periods on 1/40-acre 

plots in Fern Canyon

10 minutes

15

30

1 hour

2

3

4

6

9

12

Total, in Inches, 

Feb. 27 to Mar. 3

Precipitation

per hour

1.56

1.52

1.36

1.35

1.26

1.20

1.12

.98

.91

.79

20.44

Maximum runoff in inches per hour

Plot 349

0.0186

..0186

.0176

.0162

.0159

.0143

.'132

.0107

.0099

.0083

.17

Plot 341

0.0198

.0176

.0121

.0101

.0109

.0099

.0090

.0085

.0070

.0056

.08

Plot 345

0.0086

.0065

.0055

.0050

.0048

.0047

.0043

.0036

.0032

.0027

.06

runoff rates. For a total rainfall of 20.44 inches during the storm, 

these three plots showed a direct surface runoff of only 0.17, 0.08, and 

0.06 inch each, respectively. With an average rate of rainfall of 1.52 

inches an hour for a 15-minute period, the direct surface runoff amounted 

to less than 0.02 inch an hour. Observations made on plots at Tanbark 

Flats showed characteristics very similar to those of the plots at Fern 

Canyon.

Fern Canyon Watersheds Nos. 2 and 3 (see pi. 15) are less than half 

a mile from the Fern Canyon plots. Of these watersheds, No. 2 showed a 

maximum runoff of 0.69 inch an hour for a 15-minute period, and No. 3 

showed 0.33 inch an hour, maxima that are considerably higher than those 

for the plots.

Observations at the plots indicate a surface runoff of less than 0.2 

inch, but a considerably higher rate of infiltration than watersheds Nos. 

2 and 3, which, with a storm rainfall of 23 inches, produced a runoff of 

about 9 and 4 inches, respectively. (See table 16.) It appears that a 

considerable part of the precipitation that was absorbed by the soil 

mantle, as shown by the plot experiments, passed on through the underlying much-fractured rock and thence into the streams and that its movement 

was rather rapid. This procedure is. more pronounced for Watershed No. 2 

than Watershed No. 3. The geologic conditions which may account, in part, 

for this difference in rate of movement are discussed on page 334. The 

rate was undoubtedly influenced by the steepness of the land surface, the 

depth of the soil mantle, the nature and extent of rock outcrops, and the" 

amount of water already in storage within the formations.

The apparently rapid flow of a large part of the infiltrated water 

to the stream channel seems to introduce difficulty in the derivation of 

infiltration capacities which are of practical utility.

4S4T20 0-42-12
168 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA 

DETERMINATION OF FLOOD DISCHARGE

The method most commonly employed by the Geological Survey in the 

determination of stream discharge consists of the determination, first, 

of a stage-discharge relation or rating by means of current-meter measurements of discharge at various stages from low water to high water and 

the application of this rating to the records of stage. If the stagedischarge relation for a station has been determined throughout the range 

of flow, it is evident that if the stage at any particular time is known 

and normal flow conditions prevail, the rate of discharge past the station at that time may be ascertained by application of the rating. It is 

very difficult to determine the discharge during abnormal flood stages in 

most localities, and the accuracy of the result arrived at usually depends on surveys, analyses, and computations, by various more or less indirect methods, for extending the stage-discharge relation beyond the 

range covered by current-meter measurements.

The difficulties which make it practically impossible to obtain direct measurements of discharge or to define stage-discharge relations 

during flood periods at most stream-measurement stations in southern 

California have been discussed in the section on basic discharge records. 

Records of discharge during the floods of March 1938 have of necessity 

been determined by a combination of the methods that have been developed 

by the Geological Survey in connection with stream gaging and studies of 

other floods. Particularly helpful in this connection have been the 

checks upon estimates of discharge afforded by the relations between 

rainfall and runoff as developed from a study -of the basic discharge records and described in the next preceding section of this report.

Computation of peak discharge

Peak discharges were evaluated in a variety of ways suited to the 

conditions at the site and the kind of basic information that was available or could be found. Wherever possible, the results as determined by 

one method were verified by checking them with results as determined by 

other methods.

The discharges were determined by slope-area surveys and related 

methods based fundamentally on the application of the Chezy formula. 

They were also determined from data concerning flow over weirs and through 

contracted openings, by the extension of rating curves with the aid of 

various techniques, by analyses of reservoir records as previously described, and by various methods involving comparison of basic factors.
DETERMINATION OP FLOOD DISCHARGE 169

Peak discharges computed from a survey of pertinent conditions made 

subsequent to the peak are subject to errors introduced by unstable channels. Valley-floor streams usually nave beds composed of sand and light 

gravel. At many places in these streams there was considerable scour 

during the higher stages, and the scour was probably greatest at the time 

of the peak discharge. On these streams the bed was prodded with a round 

iron rod and the rod forced by hand to a comparatively firm bottom that 

was considered to have been the bottom of the section at the time of the 

peak discharge.

Streams in the mountain areas have steep slopes and consequently 

high velocities. Their beds are gsnerally composed of loose boulders and 

gravel, which are moved in large quantities because of the high velocities. These swift streams move from side to side in the canyons, depositing or removing debris first on one side of the channel and then on the 

other. Cross-sectional areas determined after the floods have subsided 

may or may not be the same as at the time of the peak discharge. Debris 

moving downstream may have raised the water surface locally until it was 

higher for smaller discharges than for the peak discharge. Turbulence 

may have caused splash or run-up marks on the banks higher than the controlling high-water levels. Because it is necessary to apply indirect 

methods of determination for such streams attempts were made to select 

reaches where these unfavorable influences would be least complicating.

Field data were obtainsd for certain streams in the San Bernardino 

and San Gabriel Mountains at places where channel conditions were extremely unfavorable, and it was found desirable to discard peak discharges 

computed from the data obtained at some of these places. A view showing 

typical channel conditions on these streams is presented in plate 16,A.

Slope-area determinations

Peak discharges were determined at many river-measurement stations 

and on miscellaneous streams by means of slope-area studies. Discharges 

were computed from measurements of the cross-sectional areas and slope by 

the use of formulas which have had extensive practical application. The 

formula generally used was the Manning formula, usually written as:

v . 1.486 R2/3 s| 

n

in which V = mean velocity in feet per second, n = coefficient of roughness, R hydraulic radius in feet, and S B friction slope.
170 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The selection of values of n has been guided by the results of the 

Survey's experience in the use of the slope-area method, and the values 

chosen were selected in the light of the few data available for streams 

in southern California.

The friction slope was generally computed from the hydraulic gradient 

of the peak stage as determined from high-water marks, on the basis of the 

difference in weighted velocity heads at the end sections. 15a For streams 

whose velocity at the downstream section was less than at the upstream 

section, it was assumed that there was a 50 percent recovery of the theoretical kinetic energy head. Cross sections were divided into parts to 

provide for variation in the hydraulic radii and coefficient of roughness.

As an example of the application of the slope-area method, the basic 

data used in determining the peak discharge of Lone Pine Creek near Keenbrook are shown in figure 32. A view of the reach is shown in plate 16,B.

On some streams reaches of channel were surveyed in which the changes 

in channel shape and slope made them unsuited to normal methods of analysis. The peak discharge was computed singly for each cross section on 

the basis of the Manning formula or the varied-flow equation given by 

Rouse. 16

Flow over weirs

The basic formula for the computation of flow over weirs is commonly 

expressed as Q = CLHn , in which Q = discharge in second-feet, C = coefficient for the weir, L = effective length of crest in feet, H = head in 

feet on the crest measured far enough above the weir to avoid surface 

draw-down, and n = the exponent of H. The exponent n may be assumed to 

be 1.5, and under this assumption the coefficient C will ordinarily vary 

with the head and with differences in slope of crest. The velocity of 

approach in the channel above the weir affects the discharge over the 

weir and practically increases the head on the crest by an amount equivalent to the corresponding velocity head.

15a Johnson, Hollister, The New York State flood of July 1935: 

U. S. Geol. Survey Water-Supply Paper 773-E, pp. 253-254, 1936.

16 Rouse, Hunter, Fluid mechanics for hydraulic engineers, p. 290, 

McQraw-Hlll Book Co., 1938.
DETERMINATION OF FLOOD DISCHARGE 171

N

\ 40 ">C^: ^.

o High-water mark

0 20 40 Feet " °

.--CMCO-"""^ Creek~°" f 

 <F&*. ~~-4

^' ^r ~T~- -I*;- ~ -

120 ^-~'_jrf 260 280

" ""^x^"^ ^"^

-« _ -'^- -Low-water channel 1 

.o^^ U-~^ Section B

^"^' *" " ^J^x __ J

Sketch map

40 120 160 200 240 

Feet along center of channel

280 320

. 41

Right channe 

A 14 sq.ft. 

W 11 ft. 

P 12 ft. 

R 1.17 ft.

ain channe 

A 270 sq.ft. 

W 55 ft. 

P 58 ft. 

R 4.65 ft.

42.3 

I I Main Right bank channel 

A 268 sq.ft 

58 ft. 

62 ft. 

4.32 ft.

Right channel 

A 5 sq.ft. 

W 7 ft.

7.1 ft.

0.70 ft.

Feet

Figure 32.- Sketch map, water-surface profiles, and cross sections of the slope-area 

reach of Lone Pine Creek near Keenbrook.
172 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

The basic formula was modified to make it conform to conditions peculiar to the places of application. For example,, if the crest of a weir 

was submerged, this submergence was considered in computing the discharge 

over the weir. The exponent n was generally taken as 1.5, and values of 

C were selected from data summarized in Water-Supply Paper 200, "Weir 

experiments, coefficients, and formulas," or from those contained in 

handbooks.

Flow through contracted openings

The peak discharge was_computed at some sections where the stream 

channel was constricted by bridge abutments or by natural rock formations. 

At these sections, the area of the cross section of the opening was much 

less than that of a cross section of the channel above, resulting in an 

increase in velocity through the contracted section. This increase in 

velocity could be produced only by converting head into velocity, and the 

head so used caused a sharp drop in the water surface through the opening. 

The velocity was computed by the formula, V = C V2 gh, in which V - velocity in feet per second, C = coefficient of section, g = gravity, and h - 

head at most contracted section (surface drop through opening plus velocity of approach).

The values selected for C have been based mostly on experiments by 

Yarnell. 17

Extension of rating curves

The rating curve showing the relations of stage to discharge may, under favorable circumstances, be extended to stages and discharges higher 

than the range defined by current-meter measurements. The most favorable 

conditions for the accurate extension of a rating curve are furnished by 

well-defined rapids or riffles below the gaging station at all stages, 

and a uniform increase of channel cross section as the stage increases 

without abrupt changes in area or the addition of overflow channels.

Many of the gaging stations within the area affected by the March 

floods were of necessity located where both the banks and the bed of the 

natural stream channel were composed of easily erosible sand or light 

gravel, so that there was not a permanent relation between stage and discharge .

17 Yarnell, David L., Pile trestles as channel obstructions? U. S. 

Dept. Agrl., Tech. Bull. 429, July 1934; Bridge piers as channel obstructions, U. S. Dept. Agri., Tech. Bull. 442, November 1934.
DETERMINATION OF FLOOD DISCHARGE 173

There were some channels, however, in which the process of scour and 

fill was less active. At these stations it is believed the rating curves 

can be extended with a fair degree of accuracy by assuming that nature, 

by scour and fill within the channel, maintains a rather definite relation between slope and elements of the cross section. This relation is 

obtained by plotting, to logarithmic scales, the mean depth against the 

mean velocity for each current-meter measurement. The rating curve may 

be extended to the peak stage by computing the mean depth from the cross 

section believed to have existed at this stage. The extension, of course, 

involves evaluation of the friction factor and slope through the range of 

stage. This method is further discussed in the succeeding section on 

"Discharge in unstable channels."

Discharge in unstable channels

For streams having unstable channels the relation between stage and 

discharge is generally variable, and the determination of discharge may 

involve the introduction into the process of one or more additional factors and the development of multiple rating curves. Conditions conducive 

to instability are prevalent in the alluvial channels of the streams of 

southern California, particularly during floods. It has been found useful on these streams to plot logarithmically mean depth against mean 

velocity for each discharge measurement.

It can be assumed that this relationship may be expressed as V - Cdn, 

in which V velocity in feet per second, C « a constant, d = mean depth 

in feet, and n the exponent of d. In channels in which the width is 

great compared to the depth, the hydraulic radius of the Manning formula 

should approach in value the mean depth, and the exponent of the mean 

depth should approach the value of the exponent of the hydraulic radius. 

The results of a current-meter measurement at the control section will 

define the constant C, which represents the C 1 *^6 s*) factor of the Manning formula. Assuming that this Constant is applicable for a wide range 

of stage, then it is possible to develop a rating curve for this control 

section that was applicable at the time the measurement was made.

Additional current-meter measurements made at the same site may show 

a different constant, indicating a change in slope or friction factor. 

Using each new measurement and its resulting constant, additional rating 

curves can be developed that embody cross section, slope, and friction 

factor at the time the measurement was made.
174 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

In the application of this method to determine flood discharges, advantage should be taken of all pertinent Information regarding the conditions of flow at the higher stages and of any determlnations^f discharge 

by other Indirect methods as previously discussed.

Computation of continuous records of discharge

The most accurate continuous records of flow during the flood were 

based on volumetric determinations of discharge Into reservoirs. The 

computations were made from records of stage In the reservoirs, taking 

Into consideration, also, the Information available concerning storage 

capacity and discharge through spillways and other outlet structures. 

The records of Inflow to these reservoirs and of flow at certain other 

stations are Included in a preceding section of this report, "Basic discharge records," in which the methods of determining them and their accuracy are discussed. The records in that section have been utilized in 

the analysis of basic relationships between rainfall and runoff.

Continuous records 'through the flood period were also available for 

a group of stations, principally on the valley floor, operated by the 

Corps of Engineers, United States Army, and the Los Angeles County Flood 

Control District. At these stations current-meter measurements of discharge were made at frequent intervals. For example, during the period ( 

February 28 to March 4, 1938, 18 measurements were made on Ballona Creek 

near Culver City and 44 on Los Angeles River at Los Angeles. Even at 

stations where frequent measurements were made, however, parts of the 

records are questionable because of unstable channel conditions.

At a large number of the gaging stations the records for the flood 

period were seriously deficient. At 26 stations the water-stage recorders 

and accompanying equipment installed by the Geological Survey were completely destroyed. Many water-stage recorders installed by the Los 

Angeles and Orange County Flood Control Districts were also destroyed. 

At these gaging stations all records made during and shortly prior to the 

major flood period were lost.

Several of the gage-house structures were battered and overtopped by 

the flood, which stopped the recorder clocks and caused the loss of subsequent records. The wells of many stations were filled with silt, making 

them inoperative during parts of the flood period. The scouring and filling of the stream beds at many stations made it impossible or very difficult to establish any relation between gage height and discharge. This 

is illustrated by figure 33, which shows actual cross sections of channel
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 16

3^^^%^^^^«^p^ 

'^&:'^J^.^& '3&yh^***;: - A!

^. EAST ETIWANDA CREEK NEATC ETIWANDA. 

Lookiag downstream at reach below falls and near mouth of canyon: a typical mountain stream channel.

B. SLOPE-AREA REACH ON LONE PINE CREEK NEAR KEENBROOK. 

Looking downstream.

DETERMINATION OF FLOOD DISCHARGE 175

tqf'
176 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

of the East Fork of San Gabriel River at the cableway at Camp Bonlta as 

determined several times during the flood period. At several rivermeasurement stations artificial masonry controls were badly battered and 

rendered ineffective. The destruction of highways also Interfered seriously in the work of obtaining needed data at gaging stations.

Every possible effort has been made to fill In missing records made 

during the flood so that wherever practicable complete records of discharge volumes may be available. All available information has been 

utilized to make these substituted records as reliable as possible. Many 

of the missing records were filled In and checked by comparing hydrographa 

for the stations to which they appertain with hydrographs for stations of 

like characteristics. The relations developed In the analysis of rainfall and runoff for the basic discharge records have also been utilized 

extensively In estimating missing records. A discussion of the procedure 

and an example of the derivation of flow for a gaging station with a period of missing record is discussed in the following section.

Derivation of discharge for periods of missing records

The general procedure for determining the discharge for periods of 

missing or unsatisfactory record was to prepare hydrographa based on all 

available data, including such discharges as were complied from fragmentary observations of stage, current-meter measurements, and slope-area 

and other similar determinations of discharge. These hydrographs were 

plotted on semllogarlthmlc paper, with the discharge expressed in Inches 

of runoff over the area or In second-feet per square mile in order that 

the data might be compared readily with those for adjacent or comparable 

areas.

In general, the records at the various gaging stations were complete 

and fairly satisfactory to the morning of March 2, although some had already been lost through the destruction of the recording-gage structures. 

Commonly, therefore, the problem resolved Itself into a determination of 

the discharge during the period of the main flood, on March 2, and during 

the period of recession until such time as observations could be resumed.

In many instances helpful information regarding the flow was obtained by translating the rates of rainfall for a given drainage basin, 

based on recording rain-gage records within or-near the basin for the 

maximum 24 hours, into rates of discharge by the application of relations 

determined from the basic discharge records. The method used In completing the missing record for City Creek near Highland is presented as a
DETERMINATION OF FLOOD DISCHARGE 177

typical example of the procedure. The available information consisted of 

a gage-height record continuing until about noon March 2, and the results 

of a slope-area determination of the peak discharge.

The isohyetal map indicates that the average precipitation over City 

Creek Basin (drainage area, 19.8 square miles) during the entire storm 

period was about 19 inches. This rainfall was distributed through the 

period on the basis of continuous records obtained from the recording 

rain gage at Del Rosa (altitude, 2,250 feet), located near the mouth of 

Strawberry Creek, about 5 miles southwest of the center of City Creek Basin. On this basis the precipitation for the basin was 11.2 inches for 

the maximum 24-hour period, or at a rate of 0.47 inch an hour; 8.5 inches 

for the maximum 12-hour period, or at a rate of 0.71 inch an hour; and 

proportionately less for shorter periods down to the maximum 15-minute 

period, for which the rate was estimated as 2.3 inches an hour. These 

rainfall rates are plotted on figure 34.

The relation between rates of rainfall and runoff for City Creek Basin are assumed to be very similar to those for the basins of Eaton, 

Dalton, Sawpit, Pacoima, and San Dimas Creeks as shown in figure 29. For 

this group, the maximum 24-hour rainfall ranged from 9.6 to 12.2 inches, 

the average being 11.0 inches.

On figure 29 is shown also an average curve of these relations for 

the basins above named, which was assumed to apply also to City Creek. 

By applying the assumed rates of rainfall to this average curve the corresponding rates of runoff were determined and used to define the runoff 

curve shown on figure 34. This figure is comparable with figures 25 and 

26.

The slope-area determination for City Creek near Highland indicates 

a peak discharge of 6,900 second-feet which is equivalent to 348 secondfeet to the square mile, or a rate of runoff of 0.54 inch an hour. This 

hourly rate is plotted on figure 34 as representing a discharge that 

lasted for 5 minutes. By this point and the other points representing 

rates of runoff, obtained as above described, a line Is defined that is 

assumed to show the rates of runoff for the City Creek station for periods of time ranging from 5 minutes to 24 hours.

On figure 35 are plotted the times of occurrence of the various 

maximum rainfall periods as observed for the recording rain gages at Del 

Rosa and Devil Canyon.
FLOODS OF MARCH 1936 IN SOUTHERN CALIFORNIA

7

O OJ 

rH O
DETERMINATION OF FLOOD DISCHARGE 179

Average preclpitation.based on 

Devil Canyon and Del Rosa record

March 1 March 2 March 3 March 4

Figure 35.- Time of occurrence of indicated maximum precipitation periods as obeerved

at Devil Canyon and Del Roea, and probable time of occurrence of runoff of City Creek,

 with discharge hydrograph of City Creek near Highland, March 1-4.
180 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

On the basis of the general knowledge of the behavior of streams in 

the region, the lag between rainfall and runoff on City Creek for the 

maximum 1-hour period was assumed to be about an hour. The beginnings of 

the maximum periods of more than 6 hours were within the period of the 

observed record. The lag for the 12-hour period is assumed to be 5 hours 

and is comparable with the data shown on figure 31.

On figure 36 is shown, also, the estimated hydrograph of City Creek 

for the period March 1-4. The record of discharge from midnight of February 28 to noon of March 2 was obtained from the gage-height record and 

a fairly well defined stage-discharge relation.

In the upper right hand part of the lower part of figure 35 is a 

curve that shows the rates of discharge for the maximum 24-hour period, 

ranged in the order of magnitude as derived from the data obtained from 

the runoff curve shown on figure 34. With this curve showing the rates 

of discharge and the curve in the upper part of figure 35 indicating the 

times of occurrence of maximum average rates for specified intervals, the 

hydrograph was completed through the maximum 24-hour period.

Table 22 furnishes a comparison, between City Creek and San Dimas 

Creek on the basis of the ratios of the maximum discharge and the maximum 

average discharge for selected periods to the discharge and average discharge for the maximum 24-hour period as well as the ratio of the maximum 

average discharge of each of the 14 areas given in table 13 to the average 

discharge for the maximum 24-hour period in that area. The values derived 

for City Creek seem reasonable on the basis of this comparison. The 

slight differences in storm pattern and topography between the basins of 

City and San Dimas Creeks may account for the higher ratio on City Creek 

of the maximum discharge to discharge for the maximum 24-hour period.

Table 22.- Ratio of maximum discharge for indicated periods to the

maximum 24-hour discharge for City and San Dimas Creeks and for the

average of 14 areas in southern California

S.tream

Santa Ana River Basin

City Creek

San Gabriel River Basin

San Dimas Creek

Average of 14 areas a

Drainage 

area

19.8

16.5

-

Peak

3.11

2.63

2.72

1 

hour

2.50

2.44

2.45

3

hours

2.33

2.38

2.22

6 

hours

2.01

2.06

1.92

12 

hours

1.52

1.62

1.48

18 

hours

1.25

1.26

1.19

a From table 13.
DETERMINATION OP FLOOD DISCHARGE 181

The discharge of City Creek for the period March 4-11 was estimated 

on the basis of a general study of recession characteristics as described 

below and a current-meter measurement on March 11.

On figure 36 are drawn retention curves for several of the stations 

listed in table 17. The characteristics of these curves shown on logarithmic projection seem to conform to a theory that the discharges following flood peaks, if so plotted, approximate a linear relation to the 

amounts of water retained as ground storage. 

20.0

17.5

15.0

12.5

10.0

8.0

Little IIISanta Anita 11Creek f-*'"

9 10

Figure 36.- Retention curves for certain stations in Santa Ana, San 

Gabriel, and Los Angeles River Basins.

Beginning with the retention in City Creek Basin at noon on March 3, 

computed from the hydrograph just developed, a straight line was drawn 

approximately parallel to the other lines, and the runoff for each day 

was then determined from the drop in this retention curve. These amounts 

of runoff appear reasonable and w$re checked by the current-meter measurement on March 11. The significance of retention is discussed at some 

length in a later section of this report.

The determination of the record by the foregoing procedure necessarily involves assumptions with respect to the factors entering into it, 

such as the rainfall rates that occurred on City Creek, the time of their 

occurrence, the selection of a suitable relationship between rainfall 

rates and runoff, and the estimate of the lag between rainfall and runoff 

in City Creek Basin. Also affecting the computed record are the possible 

complicating influences due to basing the fundamental rainfall-runoff 

records on discharge that includes more or less debris flow. The
182 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

procedure Involves to a large degree the application of the experience 

and knowledge of the authors, gained In their long-time observation of 

the runoff characteristics of streams in southern California.

From the records of discharge throughout the flood period as thus 

deduced, the mean dally discharge for each of the missing days may be 

readily computed and complete record thus be provided for publication.

The foregoing method and modifications of It for adaptation to varying circumstances, as well as other devices, have been used to fill in 

the discharge record for days for which this record Is missing. The description accompanying the discharge tables gives information regarding 

the methods used in completing the records. High accuracy cannot be 

claimed for the results, but they are believed to be trustworthy enough 

to be used in studying the general characteristics of flood runoff in the 

reg ion.

Consistency of determinations of flood discharge

Comparison of the intensity-duration relation for the runoff of City 

Creek Basin near Highland, as shown In figure 34, with the intensityduration relation for the runoff of other drainage areas, as shown in 

figures 25 and 26 and elsewhere, seems to demonstrate that the maximum 

runoff rates of City Creek Basin as Indicated by the rainfall-runoff 

study and also by the slope-area determination tend to be mutually confirmatory. Similar confirmation was obtained at several other places.

At the following gaging stations substantial differences were found 

between estimates of discharge obtained by rainfall-runoff studies and 

those obtained by slope-area and other methods: Devil Canyon Creek near 

San Bernardino, Waterman Canyon Creek near Arrowhead Springs, Cucamonga 

Creek near Upland, San Antonio Creek near Claremont, and Strawberry Creek 

near Arrowhead Springs. These differences reflect the difficulties Inherent In the determination of peak discharges under the existing conditions as well as the part played by personal Judgment In the interpretation of the data. The estimates of discharge as published in this report 

are intermediate between those obtained by rainfall-runoff studies and 

those obtained by slope-area or other methods. An evaluation of the 

maximum discharge of these streams has been made on the basis of the composite judgment of engineers of the-Geological Survey.

There was a wide discrepancy between the estimates of discharge of 

the Santa Ana River near Prado as obtained by different methods and different engineers. These estimates ranged from less than 80,000 to more
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 17

A. SAN GABRIEL RIVER NEAR AZUSA. 

In lower end of San Gabriel Canyon. Slope of channel about I percent.

B. CUCAMONGA CREEK NEAR UPLAND. 

Shelter is designed to withstand rocks falling from the canyon walls. Slope of channel about 4 percent.

RECONSTRUCTED GAGING STATIONS REPLACING STRUCTURES 

DESTROYED DURING THE FLOODS OF MARCH 1938.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 18

A. SAN ANTONIO CREEK NEAR CTAREMONT. 

In steep mountain canyon. Slope of channel about 12 percent.

B. DEEP CREEK IN EAR HESPER1A. 

At lower end of canyon in desert area. Slope of channel about 1 percent.

RECONSTRUCTED GAGING STATIONS REPLACING STRUCTURES DESTROYED DURING THE FLOODS OF MARCH 1938.
RECORDS OP STAGE AHD DISCHARGE AT STREAM-GAGING STATIONS 183

than 140,000 second-feet. The difficulties at this gaging station included that of the uncertainty as to the cross-sectional area of the 

channel, that of the definition of the slope of the water surface at the 

time of the maximum discharge, and other complications typical of the 

shifting channels found in the unstable alluvial material of flood plains 

on the valley floor. The maximum discharge adopted for publication in 

this report is 100,000 second-feet. Obviously this estimate is subject

to considerable error, and wherever it is used appropriate allowance

\ 

should be made for its possible inaccuracy.

Great effort was made to collect accurate and complete field data on 

practically all the larger streams in the area covered by the flood in 

order to better determine their maximum discharges. The surveys were 

made by engineers of the Geological Survey chosen either because they had 

long been familiar with the streams in this region or because of their 

long experience in studying floods in other sections of the United States. 

A large amount of time was spent, both in the field and office, in attempting to coordinate and reconcile results that were discordant because 

of the extraordinarily unfavorable conditions prevailing along these 

stream channels. A record of all the information collected, however, and 

the results of the computations are on file at the Los Angeles office of 

the Survey and are available to anyone who may wish to make further study 

of them.

RECORDS OP 'STAGE AHD DISCHARGE AT STREAM-GAGING STATIONS

One of the principal purposes of this report is to record the available information regarding the discharge of streams in southern California during the floods of March 1938 in more detail than appears In WaterSupply Papers 860 and 861, the reports on this region for 1937-38 published by the Geological Survey as parts 10 and 11 of its annual series 

on surface water supply of the Halted States. This information is useful 

In comparative studies of the characteristics of floods and in planning 

flood protection and control by means of reservoirs, levees, and channel 

Improvements. The records should also be helpful in the planning of future bridge and highway construction as well as in the design and layout 

of hydraulic and other structures that may have a relation to the channels of the streams or their flood plains.

The records published in this report are for streams on which floods 

occurred in March 1938 or which are adjacent to the margins of the storm 

area and therefore serve to define the extent of the floods. In this

454720 0-42-13
184 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

section are presented the available records for most of the stream-gaging 

stations in the flooded region. The records for a few stations have already been presented as basic discharge records. The latter were analyzed 

to bring out details that might lead to a better interpretation of the 

often meager data available at most stations.

Explanation of data

The data systematically collected at stream-gaging stations consist 

of recbrds of stage, measurements of discharge, and other technioa-1 information useful in determining the daily flow. The records of stage are 

generally obtained by water-stage recorders, which give a continuous 

graphic record of the fluctuations. Measurements of discharge are usually 

made with a current-meter according to methods outlined in standard textbooks on the measurement of stream discharge. Typical stream-gaging 

stations, equipped with water-stage recorder and measuring cable and car, 

are shown in plates 17 and 18.

Because of the unusually destructive character of the floods of 

March 1938, as already outlined, many of the regular stream-gaging stations were destroyed or so badly damaged that no record of stage was 

obtained. Furthermore, it was practically impossible during the flood 

period to obtain current-meter measurements in either the mountain or the 

valley-floor areas. Other difficulties in the determination of discharge 

have been discussed in the preceding section and at other places in this 

report.

In general the data presented for each stream-gaging station comprise a description of the station, a table of daily and monthly discharge 

throughout the 3-month period February to April 1938, and a table of 

stage and discharge at hourly or other indicated intervals, if these are 

available," generally from February 27 to March 4. The presentation of 

the data has followed a uniform plan as far as practicable.

The description of the station contains, in the first paragraph, 

information relating to the location of the gage and the approximate altitude of the stream channel at the gage. The second paragraph gives 

certain characteristics of the drainage area. The third paragraph, which 

relates to the gage-height record, gives a statement as to the type of 

record and the period for which a gage-height record was available. The 

fourth paragraph, entitled "Discharge record," contains information con- ' 

corning the method used to compute the discharge. If a gage-height 

record was available and the stage-discharge relation could be defined,
EXPLANATION OF DATA 185

Information Is given concerning the range to which the rating curve Is 

defined by current-meter measurements and the method used to extend the 

rating curve to the peak of the flood. The fifth paragraph, headed 

"Maxima," lists the discharge, time, day, and gage height, If available, 

of the peak flow during the March flood. Similar Information Is Included 

for the largest flood that occurred during the period of record preceding 

March 1938. The sixth and final paragraph, under the heading "Remarks," 

furnishes data concerning storage or diversions upstream from the station 

and other miscellaneous Information.

The table following each station description shows the mean daily 

discharge in second-feet, mean monthly discharge In second-feet, and 

monthly runoff in acre-feet, generally for the period February 1 to April 

30, 1938. This covers the flood period and sufficient time before and 

after to show the relation of flood discharges to the prevalent discharges 

and to give a general perspective of the March floods.

The table of gage heights and discharges at indicated times was designed to present the details of the rise and recession of the flood. It 

is accompanied by footnotes giving supplemental records of discharge if 

these are needed to define more accurately the subsidiary peaks or valleys 

In the hydrograph that would otherwise not be disclosed In the hourly or 

bihourly listing. For those stations for which there is little fluctuation in the hydrograph, mean values are sometimes used, as Indicated by 

bra*** showing the period for which the mean is given. The stages at indidated times were obtained from the water-stage recorders Insofar as 

such records were available. The discharges at indicated times were generally obtained from the gage heights by application of the rating table, 

usually allowing for corrections due to shifting-control.

The records are arranged in accordance with the regular plan used by 

the Geological Survey in its annual series of reports on the surface 

water supply of the United States. The only exception is that in the annual series, records for the part of the Great Basin that is In California 

(part 10) are published separately from those for the remainder of California (part 11), whereas in this report the Great Basin records follow 

Immediately after those for the south Pacific slope basins.

Reference should be made to the water-supply papers of the Geological 

Survey for other records of flow of many of the streams discussed In this 

report.

The records In this report are based on all the information available 

at the time of its compilation. Any revisions found necessary will be 

published In subsequent water-supply papers.
186 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORKIA

Tla Juana River BaaIn 

Cottonwood Creek at Morena Dam, Calif.

Location.- Lat. 32°41'00", long. 116°32'55", In SWi sec. 14 T. 17 S., R. 4 E., at

Morena Dam, 1-3/4 miles above junction with Hauser Creek. Altitude of stream bed, 

2,882 feet.

Drainage area.- 120 square miles.

gage-height record.- Gage read daily at 7 a.m.

Remarks.- Records of discharge computed from discharge over spillway, change In contents, leakage, evaporation, and direct rainfall on surface of reservoir. Altitude 

of top of spillway gates, 3,045 feet. Storage capacity, 67,211 acre-feet. Records 

furnished by City of San Diego Water Department.

Qage height, In feet, and contents, In acre-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

February

Feet

149.99

150.13

15O.15

150.21

150.29

150.31

150.31

150.32

150.33

150.41

150.43

150.67

150.71

150.73

150.76

150.78

150.81

150.82

150.92

150.95

150.97

150.98

150.99

151.00

(a)

151.01

151.09

151.50

Acre-feet

46,553

46,746

46,773

46,856

46,967

46,994

46,994

47,008

47,022

47,132

47,160

47,491

47,547

47,574

47 , 616

47,643

47,685

47,699

47,837

47,878

47,906

47,919

47,933

47,947

-

47,961

48,072

48,643

March

Feet

151.88

152.18

155.00

156.22

156.65

156.89

157.05

157.22

157.40

157.51

157.60

157.87

158.42

158.73

158.90

159.03

159.17

159.29

159.39

159,48

159.55

159.63

159.71

159.78

159.84

159.90

160.00

160.08

160.16

160.25

160.32

Acre -feet

49,179

49,606

53 , 680

55,494

56,137

56,503

56,748

57,007

57,282

57,450

57,587

58,000

58,848

59,328

59,591

59,831

60,232

60,576

60,832

61,119

61,320

61,549

61,778

61,978

62,150

68,321

62,608

62,755

62,902

63,068

63,197

April

Feet

160.38

160.41

160.45

160.49

(a)

160.55

160.59

(a)

160.66

160. 69

160.73

160.76

(a)

160.92

160.96

161.03

161.06

161.09

161.13

161.15

161.18

161.20

161.23

161.25

161.28

161.33

161.37

161.39

161.41

161.44

Acre-feet

63,307

63,363

63,436

63,510

-

63,620

63,694

-

63,823

68,878

63,952

64,007

-

64,302

64,375

64,504

64,559

64,615

64,688

64,725

64,780

64,817

64,873

64,909

64,96ft

65,057

65,130

65,167

65,204

65,259

February March April

Mean monthly discharge, In second-feet. .......... 53.3 247 48.3

a Unable to read gage owing to heavy wind.

Cottonwood Creek near Dulzura, Calif.

Location.- Lat. 32°40'45", long. 116°40'20", in OTfi sec. 22, T. 17 S., R. 3 B., at 

Barrett Dam, about 1 mile downstream from Junction with Pine Valley Creek, and 

about 17 miles northeast of Dulzura. Altitude of stream bed, 1,446 feet.

Drainage area.- 250 square miles.

Gage-height record.- Gage read dally at 7 a.m.

Remarks.- Records of discharge represent flow Into Barrett Reservoir, computed from 

discharge over spillway, change In contents, leakage, evaporation, and direct rainfall on surface of reservoir. Altitude of top of epillway gatee, 1,615 feet. 

Storage capacity, 42,796 acre-feet. Additional storage obtained by placing sandbags on spillway. Records furnished by City of San Diego.
TIA JOASA RIVER BASIN

Gage height, In feet, and contents, in acre-feet, 1938

Day

1

Z

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

February

Feet

160.02

160.14

160.21

160.28

160.35

160.39

160.44

160.45

160.50

160.59

160.63

160. 81

160.90

161.00

161.03

161.08

161.11

161.14

161.25

161.30

161.31

161.34

161.37

161.39

161.41

161.43

161.50

162.00

Acre-feet

35,501

35,595

35,651

35,706

35,761

35,793

35,832

35,840

35,879

35,950

35,982

36,124

36,195

36,274

36,298

36,338

36,362

36,386

36,473

36,513

36,521

36,545

36,569

36,585

36,601

36,617

36,673

37,072

March

Feet

162.56

163.20

169.20

169.59

169.32

169.19

169.09

169.05

169.05

169.01

169.00

169.10

169.38

169.29

169.17

169.10

169.07

169.05

169.01

169.00

168.99

168.98

168.96

168.94

168.93

168.95

168.97

168.94

169.95

168.94

168.95

Acre-feet

37,524

38,043

43,073

43,411

43,177

43,064

42,977

42,943

42,943

42,908

42,899

42,986

43,229

43,151

43,047

42,986

42,960

42,943

42,908

42,899

42,891

42,882

42,865

42,848

42,839

42,856

42,874

42,848

42,856

42,848

42,856

April

Feet

168.93

168.94

168.92

168.91

168.90

168.93

168.94

168.95

168.91

168.90

168.93

168.94

168.98

169.10

169.19

169.25

169.31

169.38

169.45

169.50

169.55

169.58

169.60

169.61

169.66

169.70

169.73

169.75

169.78

169.79

Acre -feet

42,839

42,848

42,831

42,822

42,814

42,839

42,848

42,856

42,822

42,814

42,839

42,848

42,882

42,986

43,064

43,116

43,168

43,229

 43,289

43,333

43,376

43,402

43,419

43,428

43,471

43,506

43,532

43,549

43,575

43,584

February March April

Runoff, in acre-feet............................... 2,060 13,040 5,560

Cottonwood Creek above Tecate Creek, near Dulzura, Calif.

Location.- Water-stage recorder, lat. 32°34'10'1 , long. 116° 45 '40", in sec. 27, T. 18 3., 

H. 2 E., half a mile upstream from confluence with Tecate Creek and 5& miles south 

of Dulzura. Altitude, about 580 feet.

Drainage area.- 316 square miles.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage -discharge relation defined by current-meter measurements below 540 second-feet; extended to peak stage on the basis of mean depth-mean velocity 

relation.

Maxima.- 1938: 

1936-37:

Discharge 

Discharge

2,360 second-feet 2»30 p.m. Mar. 3 (gage height, 9.07 feet). 

2,775 second-feet Feb. 7, 1937 (gage height, 9.65 feet).

Remarks . - Records good. Regulation at Barret t and Morena Reservoirs, 10 and 18 miles, 

respectively, above station.

Mean dally discharge, in second -feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

3.5

5

2.5

3.9

3.5

2.3

2.1

1.9

2.5

5

Mar.

120

281

1,460

1,040

631

427

326

298

283

238

Apr.

92

82

78

79

75

67

63

59

51

42

Day

11

12

13

14

15

16

17

18

19

20

Feb.

6

20

10

7

6

5.5

4.8

3.9

6

5

Mar.

219

497

606

517

397

328

292

259

219

192

Apr.

41

37

41

37

25

19

13

10.

8

7.5

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

3.S

3.2

3.0

2.8

2.5

2.3

22

47

382

Mar.

167

144

135

128

121

121

121

116

114

106

96

19,830

Apr.

7.5

6.5

6.5

6

7

7.5

6

5

4.2

6

33.0

1,960
188 FLOODS 07 MARCH 1938 IN SOUTHERN CALIFORNIA

Page height, in feet, and -discharge, In second-feet, at indicated time, 1988

I

1

2

3

4

3

6

1

8

9

10

11

N

1

2

3

4

5

6

1

8

9

10

11

M

Feet [Sec. ft.

February 27

>

2.12

2.88

2.50

2.70

3.13

7.8

16

29

44

92

Feet | 3«e. ft.

February 28

3.20

3.08

2.96

2.87

2.80

2.74

2.69

2.65

2.62

2.69

2.67

2.67

2.6*7

2.66

2.67

2.60

2.62

2.62

2.60

2.59

2.69

2.62

2.69

2.73

101

85

71

61

64

48

43

40

37

36

34

34

34

33

34

36

37

37

36

36

36

37

43

47

Feet See. ft.

March 1

2.78

2.80

2.85

2.93

3.36

3.36

3.38

3.43

3.60

3.73

3.68

3.67

3.74

3.67

3.67

3.48

3.38

3.30

3.23

3.16

3.12

3.07

3.02

2.68

62

64

68

67

124

124

128

136

165

190

180

178

192

178

160

144

128

116

106

93

90

64

78

73

Feet | Sec. ft.

March 2

2.98

2.68

2.99

3.03

3.04

3.07

3.09

3.13

3.30

3.42

3.48

3.64

3.60

3.75

.00

.17

.26

.27

.30

.60

5.00

6.10

6.50

7.75

73

73

74

79

80

64

86

62

116

135

144

154

166

194

247 286*

307

310

318

403

524

965

1,160

1.280

Feet | See. ft.

March 3

8.0C

8.16

7.75

7.20

6.70

6.36

6.10

6.20

6.18

6.10

6.26

7.40

7.60

8.80

9.00

8.70

8.46

7.85

7.16

7.00

6.96

6.85

6.76

6.70

1,620

1,600

1,700

1,420

1,170

1,000

890

936

828

860

666

1,520

1,620

2,220

2,320

2,170

2,040

1,740

1,400

1,320

1,300

1,240

1,200

1.170

Feet Sec. ft.

March 4

6.66

6.60

6.60

6.60

6.60

6.60

6.60

6.60

6.60

6.60

6.60

6.55

6.50

6.46

6.40

6.30

6.25

6.20

6.16

6.10

6.05

6.00

5.65

6.60

1,160

1,130

1,130

1,130

1,130

1,130

1,130

1,130

1,130

1,130

1,130

1,106

1,080

1,060

1,080

680

656

636

615

860

866

646

. 826

* 806

Supplemental record.- Mar. 3, 2i30 p.m., 9.07 feet., 2,360 sec.-ft.; Mar. 

6.66 ft., 710 sec.-ft.j 6 p.m., 5.24 ft., 562 aeo.-ft.

5, 6 a.m..

Tla Juana River near Dulzura, Calif.

Location.- Water-stage recorder, lat. 32 C 33'60", long. 116e 46'25", In aeo. 33, T. 18 

s., R. 2 B., half a mile downstream from confluence of Cottonwood and Tecate Creeks, 

and 6f milea aouth of Dulzura. Altitude, about 560 feet.

Drainage area.- 478 square milea, of which 62 aquare milea ia In Mexico. 

Page-height record.- Water-stage recorder graph.

Die ,rge record.- Stage-discharge relation defined by current-meter measurements below 

oow second-feet; extended to peak stage on baais of mean depth-mean velocity 

relation.

Maxima.- 1638: Discharge, 3,620 second-feet 11 a.m. Mar. 3 (gage height, 6.77 feet). 

1636-37J Discharge, 4,700 second-feet Feb. 7, 1637, (gage height, 6.60 feet).

Remarks.- Records good. Flow subject to regulation by storage in Morena and Barrett 

Reservoirs, operated by City of San Diego.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

6

6

7

8

6

10

Feb.

6

13

10

11

14

11

8.6

7

7.6

13

Mar.

263

610

2,650

1,180

800

650

428

384

367

314

Apr.

123

113

106

107

104

66

88

80

66

62

Day

11

12

13

14

15

16

17

18

16

20

Feb.

13

67

36

25

21

18

16

14

16

16

Mar.

286

652

732

665

496

406

354

314

277

247

Apr.

66

55

63

63

50

42

37

31

27

24

Day

21

22

23

24

25

26

27

28

28

30

31

Feb.

11

10

8.6

8.5

6.6

5.5

40

124

16.8

1,100

Mar.

227

206

160

176

164

164

167

156

154

146

131

441

27,140

Apr.

23

22

22

21

23

26

23

21

16

22

54.1

3,220
TIA J0ANA RIVER BASIN 189

gage height, in feet, and discharge, in second-feet at Indicated time, 1956

s

1

2

3

4

5

6

7

8

9

10

11

N

1

S

3

4

5

6

7

8

9

10

11

M

Festjsec.ft.

February 27

»1.56

I

^1.73

1

»1.81

1.93

> 14

>34

> 50

80

Feet | Sec. ft.

February 28

2.18

2.12

2.05

2.05

2.02

2.07

141

120

98

98

88

104

Feet | Sec. ft.

March 1

2.07

2.10

2.17

2.19

2.29

2.32

2.40

2.42

2.47

2.57

2. 66

2.64

2.64

2.63

2.61

2.58

2.55

2.49

2.46

2.43

2.39

2.37

2.36

2.34

124

134

160

168

212

2S6

271

283

314

381

446

430

430

423

409

388

367

3S8 .

308

289

265

253

247

S35

Pest | Sec. ft.

March 2

2.33

2.34

2.33

2.34

S.36

2.36

2.37

2.41

2.45

2.50

2.57

2.55

2.56

2.60

S.73

2.80

2.87

S.91

2.93

3.03

3.S7

3.68

3.88

4.20

230

235

230

235

247

247

253

277

308

334

381

367

374

402

502

564

627

663

681

780

890

1,170

1,330

1,620

Feet | Sec. ft.

March 3

4.80

4.97

5.32

5.55

5.45

5.40

5.46

5.53

5.50

5.65

5.77

5.68

5.27

5.32

4.85

4.90

5.15

4.83

4.62

4.50

4.37

4.33

4.38

4.32

2,B30

2,440

2,800

3,120

3,020

2,980

3,080

3,180

3,140

3,350

3,520

3,390

2,830

2,900

2,400

2,460

2,680

2,380

2,160

2,040

1,900

1,860

1,910

1,850

Feet | Sec. ft.

March 4

Supplen 

5:45 p.m.

mtal records.- Mar. 3, 2s30 p.m., 2,550.sec.-ft.; 4:15 p.m., 2,540 sec.-ft. 

, 2,540 sec.-ft.

Tia Juana River near Nestor, Calif.

Location.- Water-stage recorder, lat. 320 32'55B , long. 117°05'15H , on line between seca. 

3 and 4, T. 19 S., R. 2 W., 1$ miles south of Nestor, and 3 miles upetream from 

mouth. Altitude, 25 feet.

Drainage area.- 1,668 square miles, of which 1,198 square miles is in Mexico. 

Gage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

4,100 second-feet; extended to peak stage on basis of mean depth-mean velocity 

relation.

Maxima.- 1938: Discharge, 6,760 second-feet 8 a.m. Mar. 3 (gage height, 6.38 feet). 

1936-37: Discharge, 17,700 second-feet Feb. 7, 1937 (gage height, 8.20 feet).

Remarks.- Records good. Plow subject to regulation by storage in Morena and Barrett 

Reservoirs, operated by city of San Diego, and Rodriguez Reservoir, operated by 

Government of Mexico.

Mean daily discharge, In second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

221

439

4,950

3,010

1,640

1,090

680

618

601

412

Apr.

144

130

122

119

116

110

100

88

76

63

Day

11

12

13

14

15

16

17

18

19

20

Moan monthly discharge, in second

Feb.

0

0

0

0

3.3

3.5

3.7

3.9

3.9

4.4

Mar.

522

816

1,540

1,100

670

496

598

558

522

294

Apr.

59

57

61

67

63

49

42

56

31

28

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

5

4.4

3.5

2.8

1.7

0

14

4?

3.43 

191

Mar.

272

240

220

205

193

185

189

189

181

169

158

715 

43,990

Apr.

26

20

19

18

18

18

20

20

18

17

S8.S 

3,480
FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Gage height, in feet, and discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet Seo.ft.

March 1

2.93

2.93

2.99

3.01

3.02

3.04

3.06

3.08

3.10

3.13

3.16

3.17

3.22

3.34

3.45

3.52

3.56

3.58

3.58

3.57

3.58

3.61

3.63

3.63

85

85

100

105

108

113

122

127

134

144

154

158

177

230

288

328

352

364

370

364

370

391

405

405

Feet Sec.ft.

March 2

3.63

3.62

3.61

3.59

3.56

3.54

3.50

3.47

3.46

3.43

3.41

3.40

3.41

3.42

3.44

3.48

3.53

3.65

3.75

3.83

3.90

4.00

4.25

4.55

405

398

391

377

358

334

328

310

304

288

277

272

277

282

294

316

346

4£6

512

583

650

754

1,080

1,560

Feet Sec.ft.

March 3

5.15

5.37

5.63

5.95

6.05

6.15

6.25

6.38

6.30

6.10

5.95

5.90

5.95

5.90

5.67

5.50

5.30

5.35

5.55

5.90

6.20

6.17

6.05

5.97

2,880

3,470

4,200

5,220

5,560

5,920

6,300

6,760

6,480

5,810

5,280

5,110

5,280

5,110

4,370

3,890

3,330

3,470

4,030

5,110

6,160

6,060

5,640

5,360

Feet Sec.ft.

March 4

4,030

3,120

2,890

3,064

2,790

2,420

Campo Creek near Campo, Calif.

Location.- Water-stage recorder, lat. 32°35'20n , long. 1160 31 l 35n , in sec. 24, T. 18 

S., R. 4 E., at State highway about 3ff miles southwest cf Campo. Altitude, about 

2,180 feet.

Drainage area.- 84 square miles, of which 4 square miles are in Mexico.

Sage-height record.- Water-stage recorder graph except for period 3 p.m. Mar. 4 to 

12 m. Mar. 8, gage heights for which were estimated.

Discharge record.- Stage-discharge relation defined by current-meter measurements 

below 43 second-feet; extended to peak stage on basis of mean depth-mean velocity 

relation.

Maxima.- 1938: Discharge, 584" sscond-feet 1 a.m. Mar. 3 (gage height, 2.73 feet). 

1936-37: Discharge, 1,470 second-feet Feb. 6, 1937 (gage height, 3.80 feet).

arks..- Records good.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

11

13

7.5

9

10

6.5

5.5

4.8

6.5

9.5

Mar.

42

89

315

161

41

41

45

41

32

26

Apr.

14

12

12

12

12

11

10

9.5

9.5

9.5

Day

11

12

13

14

15

16

17

18

19

. 20

Feb.

13

24

15

11

9.5

10

9

8

15

11

Mar.

26

60

39

31

27

26

26

24

21

21

Apr.

9.5

10

17

18

14

11

9.5

8.5

9

8.5

Day

21

22

23

24

25

26

27

28

29

3031 '

Feb.

8.5

7

' 7

6.5

6

6

34

34

630

Mar.

18

18

17

17

16

19

23

18

21

18

15

2,650

Apr.

7

9

10

7.5

9

10

9.5

8.5

8.5

11

628
OTAY RIVER BASIN 191

Gage neight, in feet, and discharge, in second-feet, at indicated time, 1938

h

1

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet See. ft.

February 27

0.75

.78

.79

.83

.86

.90

.96

1.02

1.03

1.03

1.04

1.07

1.06

1.08

1.10

1.13

1.18

1.30

1.32

1.27

1.23

1.18

1.16

1.15

9.1

10.9

11.4

14

16

19

24

29

30

30

31

34

33

36

38

41

48

66

75

61

55

48

45

44

Feet | See. ft.

February 2S

1.13

1.12

1.12

1.11

1.10

1.08

1.06

1.05

1.03

1.03

1.02

1.02

1.03

1.03

1.03

1.03

1.06

1.11

1.10

1.09

1.08

1.07

1.06

1.06

41

40

40

39

38

36

33

32

30

30

29

- 29

30

30

30

30

33

39

38

37

36

34

33

33

Feet Sec.ft.

March 1

1.06

1.05

1.06

1.10

1.13

1.18

1.35

1.34

1.33

1.30

1.25

1.20

1.18

1.17

1.15

1.12

1.10

1.08

1.07

1.05

1.03

1.01

.98

,98

32

31

32

37

40

47

73

71

69

65

57

49

47

45

44

39

37

34

33

31

29

27

25

25

Feet Sec.ft.

March 2

0.99

.99

.99

.99

1.00

1.05

1.08

1.08

1.10

1.12

1.15

1.23

1.30

1.45

1.40

1.35

1.34

1.36

1.40

1.50

1.65

2.00

2.45

2.65

26

26

26

26

26

31

34

34

37

39

42

54

65

91

82

73

71

75

82

102

138

244

435

536

Feet Sec.ft.

March 3

2.73

2.48

2.33

2.17

2.16

2.16

2.18

2.25

2.35

2.48

2.41

2.33

2.20

2.10

2.07

2.05

2.01

1.97

1.94

1.91

1.87

1.86

1.76

1.70

584

450

376

309

304

304

313

342

385

450

415

376

321

281

269

262

248

234

223

213

200

197

167

151

Feet Sec. ft.

March 4

1.77

1.85

1.87

1.87

1.87

1.89

1.90

1.90

1.90

1.91

1.90

1.89

1.87

1.77

1.70

1.60

1.53

1.48

1.40

1.40

1.39

1.38

1.37

1.37

173

197

203

203

203

210

213

213

213

216

213

210

203

173

153

128

110

100

84

84

82

80

78

78

Otay River Baain 

Otay River at Savage Dam, Calif.

Location.- Lat. 32°36'40", long. 116°55'40n , in HWi sec. 18, T. 18 S., R. 1 E., at 

Savage Dam, at Lower Otay Reservoir. Zero of gage is 347.20 feet above mean sea. 

level. Altitude of stream bed, 347 feet.

Drainage area.- Area, 98 square miles; Average altitude, 1,535 feet. Maximum altitude, 3,755 feet. Average slope, 26 percent. Length of main stream channel, 15 

miles. Average slope of main stream channel, 4.1 percent.

gage-height record.- Sage read daily at 7 a.m.

Remarks.- Records of discharge represent inflow to Lower Otay Reservoir, computed from 

discharge over spillway, change in contents, leakage, evaporation, and direct rainfall on surface of reservoir. Altitude of top of spillway gates, 491 feet. Storage 

capacity, 56,314 acre-feet. Records furnished by City of San Diego Water Department.

Gage height, in feet,'and contents, in acre-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

February

Feet

139.93

139.95

139.92

139.89

139.91

139.90

139.86

139.83

139.81

139.78

139.76

139.83

139.83

139.79

139.76

139.74

139.73

139.72

139.68

139. 66

139.63

139.61

139.57

139.55

139.51

139.47

139.46

139.58

Acre^-feet

51,944

51,968

51,933

51,897

51,921

51,909

51,862

51,827

51,803

51,768

51,744

51,827

51,827

51,780

51,744

51,721

51,709

51,697

51,650

51,627

51,591

51,568

51,521

51,497

51,450

51,403

51,391

51,532

March

Feet

139.78

140.04

142.98

144.46

144.41

144.21

143.98

143.92

143.88

143.84

143.81

143.88

144.13

144.18

144.07

144.07

143.92

143.84

143.78

143.76

143.73

143.70

143.70

143.68

143.64

143.62

143 . 60

143.58

143.56

143.56

143.54

Acre-feet

51,768

52,075

55,666

57,550

57,486

57,228

56,922

56,846

56,795

56,745

56,707

56,795

57,125

57,189

57,047

57,047

56,846

56,745

56,669

56,643

56,601

56,567

56,567

56,542

56,491

56,466

56,441

56,415

56,390

56,390

56,365

April

Feet

143.52

143.51

143.49

143.45

143.41

143.40

143.38

143.36

143.28

143.28

143.26

143.26

143.26

143.25

143.23

143.23

143.22

143.21

143.19

143.18

143.18

143.19

143.19

143.20

143.20

143.21

143.22

143.22

143.23

143.25

Acre-feet

56,339

56,327

56,301

56,251

56,200

56,187

56,162

56,137

56,036

56,036

56,010

56,010

56,010

55,998

55,972

55,972

55,960

55,947

55,922

55,909

55,909*

55,922

55,922

55,934

55,934

55,947

55,960

55,960

55,972

55,998

February March April

Mean monthly discharge, in second-feet. ........... 15.1 282 4.32

Runoff, in acre-feet.............................. 840 17,340 257
FLOODS OP MARCH 1988 IS SOUTHERN CALIFORNIA

Sweetwater River Basin 

Sweetwater River at Sweetwater Dam, Calif.

Location.- Lat. 320 41'2011 , long. llVOO'SS", at Sweetwater Dam, in La Nacion grant, 6 

miles east of National City, San Diego County, and about 8 miles upstream from 

mouth. Altitude of stream bed, about 150 feet.

Drainage area.- Area, 181 square miles. Average altitude, 2,277 feet. Maximum altitude, 6,515 feet. Average slope, 29 percent. Length of main stream channel, 43 

miles. Average slope of main stream channel, 2.7 percent.

Page-height record.- Staff gage read daily between 7 and 8 a.m.

Remarks.- Records of discharge represent flow into Sweetwater Reservoir, computed from 

discharge over spillway, change in contents, leakage, evaporation, and direct rainfall on surface of reservoir. Storage capacity, 30,973 acre-feet. Records furnished by California Water and Telephone Company.

Gage height, in feet, and contents, in acre-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

26

26

27

28

29

30

31

February

Feet

81.44

81.51

81.59

81.64

81.70

81.76

81.81

81.83

81.86

81.91

81.94

82.06

82.19

82.24

82.26

82.29

82.34

82.36

82.40

32.42

82.45

82.47

82.48

82.48

82.49

82.49

82.54

82.72

Acre-feet

21,624

21,680

21,744

21,784

21,833

21,882

21,923

21,940

21,965

22,006

22,031

22,129

22,236

22,277

22,294

22,319

22,360

22,376

22,409

22,425

22,450

22,466

22,475

22,475

22,483

22,483

22,524

22,673

March

Feet

83.14

83.96

89.57

89.76

89.45

89.49

89.54

89.74

89.58

89.58

89.63

89.68

89.42

89.18

89.12

89.10

89.14

89.15

89.16

89.39

89.66

89.72

89.68

89.69

89.68

89.67

89.71

89.71

89.69

89.67

89.66

Acre -feet

23,026

23,719

28,934

29,127

28,812

28,853

28,903

29,107

28,944

28,944

28,994

29,045

28,782

28,540

28,478

28,458

28,499

28,509

28,519

28,752

29,025

29,086

29,045

29,055

29,045

29,035

29,075

29,075

29,055

29,035

29,025

April

Feet

89.68

89.73

89.75

89.72

89.70

89.69

89.70

89.68

89.68

89.69

89.70

89.70

89.70

89.73

89.74

89.73

89.68

89.68

89.71

89.75

89.76

89.74

89.72

89.73

89.75

89.76

89.77

89.75

89.74

89.74

Acre-feet

29,045

29,096

29,117

29,086

29,065

29,055

29,065

29,045

29,045

29,055

29,065

29,065

29,065

29,096

29,107

29,096

29,045

29,045

29,075

29,117

29,127

29,107 ' '

29,086

29,096

29,117

29,127

29,138

29,117

29,107

29,107

February March April

Mean monthly discharge, in second-feet. ........... 34.6 391 48.2

Runoff, in acre-feet.... .......................... 1,920 24,060 2,870

San Diego River Basin

San Diego River at El Capitan Dam, near Lakeside, Calif.

Location.- Lat. 32°53'0011 , long. 116°48'40'1 , in NEi sec. 7, T. 15 S. , R. 2 E., at El 

Capitan Dam, 1 mile downstream from mouth of Chocolate Creek, and 7 miles east of 

Lakeside. Altitude of stream bed, 553 feet.

Dra ge yea.- Area, 190 square miles. Average altitude, 2,905 feet. Maximum alt itude, 6,515 feet. Average slope, 38 percent. Length of main stream channel, 14.5 

miles. Average slope of main stream, 7.5 percent.-

Page-height record.- Oage read daily at 7 a.m,_

Remarks . - Records of discharge represent flow into El Capitan Reservoir, computed from 

discharge over spillway, change in contents, leakage, evaporation, and direct rainfall on surface of reservoir. Altitude of spillway, 750 feet. Storage capacity, 

116,500 acre-feet. Additional storage obtained by placing sandbags on spillway. 

Records furnished by City of San Diego Water Department.
SAN DZB90 RIVBR BA3XH 193

Gage height, in feet, and contents, in aore-feet, 1938

Day

1

2

3

4

e

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

3Q

31

February

Feet

177.65

177.75

177. SO

177.84

177.98

178.05

178.09

178.11

178.14

178.22

178.27

> 178.56

178.70

178.79

178.82

178.86

178.90

178.94

179.01

179.06

179.10

179.12

179.14

179.16

179.14

179.13

179.21

179. 84

Acre-feet

88,377

88,509

88,576

88,629

88,815

88,909

88,962

88,989

89,029

89,135

89,202

89,590

89,778

89,898

89,939

89,993

90,046

90,100

90,194

90,268

90,315

90,342

90,369

90,396

90,369

90,356

90,464

91,316

March

 Feet

180. 68

181.46

188.15

192.50

194.06

194.95

195.50

196.85

196.36

196.68

196.93

197.23

197.78

197.86

197.59

197.48

197.39

197.37

197.33

197.30

197.29

197.28

197.27

197.27

197.26

197.25

197.26

197.24

197.23

197.40

197.60

Acre-feet

" 92,460

93,530

103,024

109,497

111,877

113,249

114,102

114,647

115,444

115,945

116,338

116,811

117,680

117,807

117,379

117,206

117,065

117,052

116,969

116,921

116,906

116,890

116,874

116,874

116,858

116,842

116,858

116,827

116,811

117,079

117,395

April

Feet

' 197.77

197.87

197.92

197.99

198.07

198.10

198.08

198.05

198.08

197.99

197.97

197.96

197.96

198.04

198.06

198. OB

198.01

198.00

198.02

198.07

198.11

198.14

198.17

198.18

198.21

198.29

198.28

198.25

198.24

198.28

Acre-feet

117,664

117,883

117,908

118,013

118,140

118,188

118,156

118,108

118,081

118,013

117,981

117,966

117,966

118,098

118,108

118,061

118,045

118,089

118,061

118,140

118,804

118,851

118,899

118,316

118,363

118,490

118,474

118,486

118,410

118,474

February March April

Runoff, in acre-feet .....................%...... 4 ,780 42,250 5,110«

San Diego River near Santee, Calif.

Location.- Water-stage recorder, lat. 32«49 I 201', long. 117°03'25n , in Mission Gorge, 

In Bx Mission San Diego grant, 6 miles west of Santee, San Diego County. Altitude, 

about 205 feet.

Drainage area.- Area, 380 square miles. Average altitude, 2,070 feet. Maximum altifrude, 6,£l5 feet. Average slope, 38 peroent. Length of main stream channel, 40 

 iles. Average slope of main stream channel, 2.9 percent.

Sage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements 

below 4,570 second-feet; extended logarithmically to peak stage.

Maxima.- 1938: Discharge, 7,350 second-feet 2 a.m. Mar. 3 (gage height, 7.05 feet). 

1912-37: Discharge, 70,200 second-feet Jan. 27, 1916, by slope-area method.

Remarks.- Records good. Flow partially regained by El Capitan Reservoir, 26 miles 

upstream. City of San Diego diverts water from El Capitan Reaervolr.

Mean dally discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.6

.4

.4

.4

.4

.2

.2

.2

.6

.9

Mar.

496

1,700

3,770

925

470

295

200

189

165

100

Apr.

31

24

24

27

31

80

91

82

77

75

Day

11

12

13

14

15

16

17

18

19

20

Feb.

1.0

2.1

1.2

.9

.7

.9

.9

. .6

1.0

.6

Mar.

87

379

1,250

1,220

745

590

486

400

307

259

Apr.

65

60

68

75

75

75

77

77

26

14

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0.4

.3

.3

.3

.3

.2

5.5

24

1 AE>

90

Mar,

230

210

199

174

168

156

153

146

137

65

37

efui

31,140

Apr.

 18

11

13

13

84

68

69

SB

48

64

48.9

2,970
194 FLOODS OP MARCH 1938 IB SOUTHERN CALIFORNIA

Page height, in feet, and discharge, in second-feet, at indicated time, 1958

§

§

1

2

3

4

5

6

7

S

9

10

11

N

1

2

3

4

5

6

7

'98

10

11

M

Feet | Sec.ft.

February 27

0.13

.17

.19

.20

.21

.22

.23

.27

.30

.31

.32

.34

.34

.34

.41

.44

.49

.50

.50

.49

.49

.50

.60

.72

0.3

.5

.6

.7

.8

.9

.9

1.3

1.5

1.8

2.1

2.7

2.7

2.7

5

6.7

9.4

10

10

9.4

9.4

10

21

41

Feet Sec.ft.

February 28

0.70

.69

.68

.64

.62

.61

.60

.60

.59

.58

.58

.58

.58

.58

.58

.58

.58

.58

.58

.58

.58

.58

.60

.60

37 '35

34

27

24

23

21

21

20

19

19

19

19

19

19

19

19

19

19

19

19

19

21

21

Feet | Sec.ft.

March 1

0.60

.64

.75

1.11

3.00

2.40

2.40

2.31

2.21

2.92

2.80

2.50

2.37

2.31

2.25

2.17

2.10

3.02

1.95

1.8T7

1.79

1.73

1.69

1.65

21

27

47

132

480

710

710

656

596

1,100

1,000

780

692

656

620

573

535

491

455

415

375

349

332

315

Feet | Sec. ft.

March 2

1.63

1.63

1.68

1.69

1.75

1.95

2.10

3.18

2.30

2.50

3.09

3.01

2.95

3.35

3.73

3.68

3.54

3.41

3.48

4.32

5.70

6.45

6.50

6.50

307

307

328

332

358

455

535

579

650

780

1,250

1,180

1,120

1,490

1,900

1,830

1,680

1,550

1,620

2,560

4,690

6,050

6,110

6.110

Feet Sec.ft.

March 3

6.95

7.05

6.57

6.00

5.75

5.53

5.45

5.55

5.80

5.60

5.58

5.73

5.68

5.31

4.78

4.32

3.97

3.70

3.54

3.40

3.34

3.24

3.17

3.10

7,110

7,350

6,250

5,160

4,710

4,320

4,160

4,360

4,800

4,440

4,420

4,670

4,570

3,910

3,120

2,480

2,060

1,770

1,610

1,470

1,410

1,320

1,260

1,300

Feet | Sec. ft.

March 4

3.14

3.10

3.03

3.02

3.00

2.92

2.91

2.90

2.91

2.94

2.99

2.93

2.80

2.70

2.63

2.58

2.52

2.50

2.45

2.41

2.39

2.33

2.31

2,30

1,230

1,20O

1,130

1,120

1,110

1,040

1,030

1,020

1,030

1,060

1,100

1,050

944

871

822

787

745

731

698

674

662

626

614

608

Boulder Creek at Cuyamaca Reservoir, near Julian, Calif.

Location.- Lat. 32°59'15", long. 116°35'10", in KEi sec. 8, T. 14 S., R. 4 E., at 

Cuyamaca Reservoir, 7 miles south of Julian. Altitude of stream bed, 4,590 feet.

Drainage area.- Area, 12.0 square miles. Average altitude, 4,976 feet. Maximum altitude, 6,515 feet. Average slope, 20 percent. Length of main stream channel, 3.5 

miles. Average slope of main stream channel, 7.5 percent.

Page-height record.- Gage read daily at 7 a.m.

Remarks.- Records of discharge computed from* discharge over spillway, change in contents, leakage, evaporation, and direct rainfall on surface of reservoir. Altitude 

of crest of dam, 4,633 feet. Storage capacity, 11., 600 acre-feet. Records furnished 

by La Mesa, Lemon Grove, and Spring Valley Irrigation District. ~

Sage height, In feet, and contents, in acre-feet, 1938

T\A1r Day

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

February

Feet

30.62

30.83

30.83

30.92

31.12

31.12

31.12

31.12

31.12

31.21

31.21

31.37 

31.50

31.50

31.50

31.50

31.50

31.50

31.62

31.67

31.71

31.71

31.71

31.71

31.71

31.71

31.83

32.33

Acre -feet

7,565

7,738

7,738

7,806

7,978

7,978

7,978

7,978

7,978

8,047

8,047

8,185 

8,288

8,288

8,288

8,288

8,288

8,288

8,391 "

8,426

8,460

8,460

8,460

8,460

8,460

8,460

8,564

9,000

March

Feet

32.83

33.00

35.25

35.79

35.58

35.33

35.25

35.33

35.33

35.33

35.37

35.7,5 

35.*

35.42

35.33

35.42

35.37

35.42

35.42

35.42

35.42

35.42

35.4°.

35.42

35.42

35.46

35.46

35.46

35.50

35.50

35.42

Acre-feet

9,414

9,551

11,457

11,904

11,732

11,525

11,457

11,525

11,525

11,525

11,491

11,870 

11,732

11,595

11,525

11,595

11,559

11,595

-11,595

11,595

11,595

11,595

11,595

11,595

11; 595

11,629

11,629

11,629

11,663

11,663

11,595

April

Feet

35.33

35.33

35.37

35.37

35.37

35.37

35.37

35.37

35.33

35.33

35.33

35.29 

35.37

35.42

35.46

35.46

35.46

35.42

35.42

35.42

35.42

35.42

35.37

35.37

35.37

35.46

35.46

35.46

35.46

35.50

Acre-feet

11,525

11,525

11,559

11,559

11,559

11,559

11,559

11,559

11,525

11,525

11,525

11,491 

11,559

11,595

11,629

11,629

11,629

- 11,595

11,595

11,595

11,595

11,595

11,542

11,542

11,542

11,629

11,629

 11,629

11,629

11,663

February March April

Mean monthly discharge, in second-feet. .......... 33 116 16
SAN DIEGO RIVER BASIN 195

San Vleente Creek at Poster, Calif.

Location.- Water-stage recorder, lat. 32°54'401', long. 116°55'35n , in sec. 31, T. 14 

S., R. IE., naif a mile north of Foster. Altitude, about 750 feet.

Drainage area.- Area, 75 square miles.- Average altitude, 1,640 feet. Maximum altitude, 4,132 feet. Average slope, 36 percent. Length of main stream channel, 14 

miles. Average slope of main stream channel, 4.5 percent.

gage-height record.- Water-stage recorder graph except Pet). 1-10, 20-26, Apr. 1-18 and 

20-30.

Discharge record.- .Stage-discharge relation defined by current-meter measurements below 1,320 second-feet; extended to peak stage on basis of mean depth-mean velocity 

relation. Discharge for periods of missing gage-height record determined from 

current-meter measurements and comparable hydrographs of adjacent streams.

Maxima.- 1938:" Discharge, 5,270 second-feet 11 p.m. Mar. 2 (gage height, 5.59 feet). 

1915, 1916, 1936-37: Discharge, 16,600 second-feet Jan. 27, 1916, by slopearea method.

Remarks.- Records fair.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.2

.1

.1

.3

.2

.1

.1

.1

.2

.2

Mar.

433

1,380

1,790

545

872

160

133

154

138

143

Apr.

26

25

24

22

21

20

18

17

17

18

Day

11

12

13

14

15

16

17

18

19

20

Feb.

1.0

.2

.2

.2

.2

.2

.1

.1

.2

.2

Mar.

143

346

302

198

143

122

118

100

91

67

Apr.

19

20

23

20

17

16

14

12

11

10

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0.2

.2

.1

.1

.1

.1

65

123

S

ort

383

Mar.

58

52

49

42

40

34

35

35

38

34

29

OXX

14,330

Apr.

10

9

9

10

20

17

14

12

10

10

974

Gage height, In feet, and discharge, in second-feet, at indicated time, 1938

fc

S

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet j Sec. ft.

February 27

1.77

> 0.2

.343

Feet Sec.ft.

February 28

1.47

1.35

1.25

1.15

1.06

.95

.90

.93

.98

.97

.99

1.03

1.03

1.02

1.02

1.07

1.16

1.16

1.12

1.11

1.08

1.09

1.13

1.25

225

184

154

128

105

80

71

76

87

87

91

100

102

100

100

115

138

138

130

128

120

125

135

169

Feet | Sec. ft.

March 1

1.49

1.69

1.99

2.35

2.90

3.00

3.25

2.70

1.90

1.80

1.68

1.64

1.61

1.55

1.48

1.40

1.33

1.27

1.21

1.17

1.14

1.11

1.08

1.05

250

334

479

690

1,100

1,190

1,440

952

442

398

343

326

313

287

261

236

211

191

172

160

154

146

138

133

Feet Sec. ft.

March 2

1.03

1.01

.98

.98

1.00

1.10

1.19

1.27

1.41

1.74

'2.65

3.75

4.25

3.90

3.00

2.79

2.72

2.76

2.94

3.65

4.50

5.14

5.59

5.41

128

125

118

118

125

151

178

204

257

398

976

2,080

2,760

2,290

1,280

1,100

1,050

1,090

1,240

'2,010

3,200

4,340

5,270

4,920

Feet Sec.ft.

March 3

5.36

4.30

3.48

3.27

3.27

3.50

3.54

3.35

3.67

4.50

4.50

4.10

3.20

2.80

2.48

2.18

1.83

4,840

2,970

1,880

1,650

1,660

1,940

2,000

1,780

2,180

3,400

3,420

2,820

1,670

1,280

I

>1,020

1> 808

> 605

Feet Sec.ft.

March 4

1.63

1.70

1.93

2.09

1.84

1.70

1.52

1.27

 519

576

731

857

697

^ 622

> 542

> 426

1
196 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

San Plegutto River Baa In

Santa Ysabel Greek near Mesa Orande, Calif.

Loeatlgn.- Water-stage recorder, lat. 33 807'16", long. 116048'30", In HSiHWi »eo. 20, 

T. IE S., R. 2 E., half a mile upstream from confluence with Black Canyon Creek and 

4t miles southwest of Mesa Orande. Altitude, about 2,000 feet.

Drainage area.- Area, 68 square miles. Average altitude, 3,360 feet. Maximum altl- 

" tude, 8,877 feet. Average slope, 40 percent. Length of main etreau channel, 7.6 

7 miles. Average slope of main stream channel, 8.9 percent.

Sage -height record.- Water-stage recorder graph, except for period 4 p.m. Mar, 3 to 

12 m. Mar. 6, gage heights for whloh were Interpolated.

. Piaoaarge record . - Stage-discharge relation defined by current -meter measurements below 1,140 second-feet; extended to peak stage on basis of mean depth-mean velocity 

'';,. relation.

'.- 193 8 » Discharge, 8,000 second-feet 11(20 p.m. Uar. 2 (gage height, 7.30 feet). 

1912-28, 1936-371 Discharge, 21,100 second-feet Jan. 27, 1916.

Mean daily discharge, in second-feet, 1988

*T

1

8

3

4

8

6

7

8

9

10

Feb.

16

14

11

SO

26

17

13

13

14

22

Mar.

443

1,760

2,000

769

484

247

188

176

103

76

Apr.

68

65

66

68

86

79

76

72

63

60

Day

11

12

13

14

16

16

17

18

19

20

Feb.

88

66

54

26

26

26

22

19

32

20

Mar.

68

709

612

402

289

212

226

162

143

143

Apr.

64

61

76

76

64

46

40

38

34

34

Day

21

88

23

24

86

26

27

28

89

30

31

Feb.

18

16

16

16

14

15

163

196

36.2

1,960

Mar.

128

113 

103

94

94

103

103

98

108

98

82

330

20,310

Apr.

54

32

34

34

64

46

58

40

42

49

65.6

3,190

Page height, in feet, and discharge, In second-feet, at indicated time, 1958

I

1

2

3

4

5

6

7

8

9

10

11

X

1

2

3

4

6

6

7

8

9

10

11

K

Feet | Sec. ft.

February 27

 1.46

1.66

1.68

1.86

2.35

5.20

3.10

2.78

2.36

2.25

2.20

 6.6

14

26

72

588

1,010

934

671

388

312

276

Feet | Seo.ft.

February 28

2.16

2.10

2.06

2.00

2.00

1.96

2.00

2.00

2.06

2.06

2.06

2.00

2.00

2.10

2.20

2.30

2.20

2.15

2.10

2.13

2.11

2.18

2.10

2.13

240

208

169

138

158

113

138

138

189

169

169

138

138

208

276

350

276

240

208

226

212

240

206

226

Feet Seo.ft.

March 1

2.28

2.30

2.60

3.08

3.36

3.44

3.10

2.80

2.70

2.80

2.60

2.40

2.30

2.20

2.17

2.14

2.10

2.10

2.08

2.00

2.00

2.00

2.00

2.00

312

360

496

894

1,160

1,230

934

706

636

566

496

426

550

276

264

233

206

208

169

138

158

138

138

138

Feet | Sec. ft.

March 2

2.00

2.01

2.08

2.10

2.2C

2.50

2.4C

2.60

2.85

3.50

4.80

6.10

4.40

4.10

3.90

3.80

3.76

3.85

4.10

4.70

6.16

6.70

6.85

6.00

138

143

191

20S

276

380

426

666

741

1,280

2,420

3,300

2,290

1,800

1,690

1,580

1,620

1,650

1,910

2,680

3,360

4,270

6,840

4.840

Feet ] Sec. ft.

March 3

5.80

4.60

4.30

4.10

5.96

4.00

4.10

4.20

6.70

5.78

4.70

4.00

5.76

5.68

5.62

3.58

3.65

5.49

5.48

3.40

3.58

3.31

3.28

3.23

3,950

2,410

2,160

1,910

1,740

1,800

1,910

2,030

4,270

4,360

2,680

1,800

1,620

1,460

1,590

1,560

1,500

1,240

1,250

1,180

1,140

1,100

1,080

1.030

Feet | Seo.ft.

March 4

Supplemental record.- Mar. 2, 1U20 p.m., 7.50 ft., 8,000 sec.-ft.
SAN LDIS HEY RIVER BASIN

San Dlegulto River at Lake Hodges, Calif.

Location.- Lat. 33°02'55n , long. 117°07'25", In NWi see. 18, T. 13 S., R. 2 W., at Lake 

Hodges Dam, 54 miles southwest of Esoondldo. Altitude of stream bed, 200 feet.

Drainage area.- Area, 303 square miles. Average altitude, 1,690 feet. Maximum altitucLe, 4,132 feet. Average slope, 38 percent. Length of main stream channel, 37

miles. Average slope of main stream channel, 1.8 percent.

Sage-height record.- Staff gage read daily at 7 a.m.'

Remarks.- Records of discharge represent flow into Lake Hodges, computed from discharge 

over spillway, change in contents, leakage, evaporation, and direct rainfall on 

surface of lake. Altitude of spillway, 315 feet. Storage capacity, 37,530 acrefeet. Additional storage obtained by placing sandbags on spillway. Diversions for 

irrigation in San Pasquel Valley above Lake Hodges. Record furnished by City of 

San Diego Water Department*

Gage height, in feet, and contents, in acre-feet, 1938

Day

1 

2 

S 

4 

5

6 

7 

8 

9 

10

11 

12 

13 

14 

15

16 

17 

18 

19 

20

21 

22 

23 

24 

25

26 

27 

28 

29 

30 

31

February

Feet

109.09 

109.28 

109.39 

109.59 

109.73

109.90 

109.98 

110.05 

110.13 

110.20

110.30 

110.63 

111.02 

111.18 

111.29

111.40 

111.51 

111.59 

111.70 

111.85

111.94 

112.00 

112.04 

112.11 

112.14

112.17 

112.25 

. 113.51

Acre -feet

30,256 

30,474 

30,601 

30,832 

30,995

31,193 

31,287 

31,369 

31,463 

31,546

31,663 

32,055 

32,521 

32,714 

32,847

32,980 

33,114 

33,211 

33,345 

33,529

33,639 

33,713 

33,762 

33,848 

33,885

33,922 

34,021 

35,603

Mean monthly discharge, in secot

March

Feet

115.29 

116.08 

120.94 

117.22 

116.28

115.91 

115.72 

115.66 

115.67 

115.58

115.51 

115.52 

116.31 

116.13 

115.78

115.67 

115.62 

115.61 

115.57 

115.54

115.58 

115.48 

115.46 

115.60 

115.69

115.75 

115.78 

115.79 

115.76 

115.80 

115.77

id-feet

Acre -feet

37 , 917 

38,975 

45,933 

40,538 

39,247

38,746 

38,491 

38,410 

38,424 

38,303

38,209 

38,223 

39,288 

39,043 

38,571

38,424 

38,357 

38,343 

38,290 

38,250

38,303 

38,169 

38,143 

38,330 

38,451

38,531 

38,571 

38,585 

38,544 

38,598 

38,558

April

Feet

115.73 

115.67 

115.66 

115.65 

115.62

115 . 66 

115.71 

115.71 

115.71 

115.71

115.72 

115.72 

115.73 

115.85 

115.91

115.91 

115.89 

115.88 

115.81 

115.89

115.97 

116.04 

116.09 

116.11 

116.13

116.17 

116.15 

116.11 

116.06 

116.10

Acre -feet

38,504 

38,424 

38,410 

38,397 

38,357

38,410 

38,477 

38,477 

38,477 

38,477

38,491 

38,491 

38,504 

38,665 

38,746

38,746 

38,719 

38,706 

38,611 

'38,719

38,826 

38,921 

38,988 

39,016 

39,043

39,097 

39,070 

39,016 

38,948 

39,002

February March April

. . . . . . i

.................. 8,C

L45 1,147 110 

)50 70,600 6,530

San Luis Key River Basin

San Luis Rey River nsar-Bonsall, Calif.

Location.- Water-stage recorder, lat. 33°15'05", long. 117°14'55", in Jffii sec. 1, T. 

 US., R. 4 W., 'three-quarters of a mile downstream from highway bridge on FallbrookEscondldo road, and 3 miles southwest of Bonsall. Altitude, about 120 feet.

Drainage area.- Area, 514 square miles. Average altitude, 2,510 feet. Maximum altitude, 6,405 feet. Average slope, 25 percent. Length of main stream channel, 58 

miles. Average slope of main stream channel, 2.1 percent.

Page-height record.- Water-stage recorder graph.

Discha: 

low 

relation.

,rge record.- Stage-discharge relation defined fey current-meter measurements be- 

 2,360 second-feet; extended to peak stage on basis of mean depth-mean velocity

Maxima.- 1938: Discharge, 18,100 second-feet 1 a.m. Mar. 3 (gage height, 12.60 feet). 

 1912-18, 1929-37: Discharge, 16,700 second-feet Feb. 7, 1937. »

Remarks.- Records good. Regulation at Lake Henshaw, 41 miles upstream.
198 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

58

48

43

81

112

67

51

47

50

51

Mar.

2,060

4,040

9,660

2,180

1,110

757

608

591

475

394

Apr.

130

118

112

106

106

99

87

81

78

76

Day

11

12

13

14

15

16

17

18

19

20

Feb.

64

106

78

58

53

56

50

43

53

54

Mar.

345

1,310

1,140

739

505

439

401

341

294

266

Apr.

72

76 100

102

89

85

81

74

71

71

Day

21

22

23

24

25

26

27

SB

29

30

31

Feb.

43

42

42

38

36

35

116

a504

a74 2

a4,120

Mar.

246

229

193

172

178

190

164

159

162

148

136

QCft

58,770

Apr.

69

67

64

64

89

81

71

67

67

81

84 5

5,030

a Revised; supersedes figures published in Water-Supply Paper 861, p. 24.

Sage height, in feet, and discharge, in second-feet, at indicated time, 1958

uo

lx!

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet

Sec.- 

ft.

Feb. 27

 0.40

> .62

X 95

r

1.14

1.50

1.77

1.75

 45

81

}l56

1

211

337

452

444

Feet Sec.- 

ft.

Feb. 28

1.57

1.46

1.45

1.42

1.55

1.70

1.78

l;81

1.81

1.80

1.80

1.95

2.06

2.13

2.09

2.04

2.09

2.06

2.07

2.06

2.05

2.05

2.07

2.06

365

329

317

305

357

421

457

470

470

466

466

540

597

635

612

586

612

597

602

597

590

590

602

597

Feet Sec.-

ft.

Mar. 1

2.35

2.90

3.50

3.97

4.50

4.34

4.47

5.27

5.31

5.07

4.72

4.34

4.07

4.17

4.41

4.40

4.17

3.90

3.60

3.45

3.15

3.00

2.80

2.80

751

1,110

1,580

2,030

2,560

2,400

2,530

3,520

3,560

3,250

2,820

2,400

2,130

2,230

2,470

2,460

2,230

1,960

1,660

1,550

1,290

1,180

1,040

1,040

Feet

Sec.- 

ft.

Mar. 2

2.75

2.65

2.75

2.75

2.86

3.00

3.15

3.50

3.75

4.23

4.48

4.58

4.68

5.73

6.32

6.48

6.58

6.63

6.88

7.53

7.88

8.83

10.40

12.00

994

929

994

994

1,070

1,170

1,270

1,570

1,790

2,270

2,520

2,620

2,990

3,990

4,950

5,180

5,330

5,400

5,780

6,850

7,540

9,340

12,700

16,600

Feet

Sec.- 

ft.

Mar. 3

12.60

12.25

11.75

11.50

11.45

11.0

10.5

10.1

9.65

9.25

8.85

8.7

8.55

8.15

7.8

7.5

7.0

6.6

6.15

5.85

5.6

5.35

5.15

5.1

18,100

17,200

15,900

15,400

15,200

14,000

12,900

12,000

10,900

10,100

9,340

9,040

8,940

7,950

7,340

6,760

5,930

5,330

4,650

4,220

3,880

3,550

3,310

3,250

Feet Sec.- 

ft.

Mar. 4

4.95

4.63

4.65

4.52

4.4

4.32

4.35

4.21

4.37

4.26

4.23

4.35

4.28

4.17

4.07

3.93

3.88

3.90

3.68

3.65

3.5

3.5

3.5

3.45

3,050

2,660

2,680

2,540

2,420

2,340

2,370

2,230

2,390

2,280

2,250

2,370

2,300

2,190

2,090

1,950

1,900

1,920

1,700

1,670

1,550

1,550

1,550

1,510

Feet

Sec.- 

ft.

Mar. 5

3.33

3.17

3.2

3.05

3.05

2.95

2.8

2.75

2.76

2.75

2.80

2.75

1,390

1,260

1,280

1,170

1,170

1,100

993

961

961

954

987

954

San Luls Rey River at OceansIde, Calif.

Location.- Water-stage recorder, lat. 33°12'40", long. 117 0 22'40n , In NWi sec. 23, T. 

US., R. 5 W., half a mile above State highway bridge at Oceanslde. Altitude, 

about 20 feet.

Drainage area.- Area, 557 square miles. Average altitude, 2,334 feet. Maximum altitude, 6,400 feet. Average slope, 33 percent. Length of main stream channel, 68.5 

miles. Average slope of main stream channel, 1.9 percent.

Sage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 2,320 second-feet; extended to peak stage on basis of mean depth-mean velocity 

relation. Discharge computed by shifting-control method and based in part on 

comparison with discharge of San Luis Rey River near Bonsall.

Maxima.- 1938: Discharge, 16,500 second-feet 5:30 a.m. Mar. 3 (gage height, 10.77 

feet).

1912-14, 1916, 1929-37: Discharge, 95,600 second-feet Jan. 12, 1916.

Remarks.- Records poor, due to shifting control, 

diversions above station.

Storage at Lake Henshaw; numerous
SANTA HARGARITA RIVER BASIN 199

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

38

44

38

51

85

70

47

40

38

44

Mar.

2,000

2,860

11,300

2,650

1,480

1,060

798

674

568

465

Apr.

122

113

113

110

117

117

98

80

66

64

Day

11

12

13

14

15

16

17

18

19

20

Feb.

52

81

68

65

55

54

57

52

55

61

Mar.

390

1,160

1,140

613

462

402

421

421

391

330

Apr.

66

69

91

110

95

87

77

69

61

53

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

55

46

38

35

34

32

57

347

62.6

3,490

Mar.

301

262

213

193

166

200

161

151

161

156

137

1,022

62,850

Apr.

51

51

51

53

84

102

69

53

51

61

80.1

4,770

Gage height, in feet, and discharge, in second-feel:, at indicated time, 1938

w

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7 

8

9

10

11

M

Feet Sec. ft.

February 27

Feet Sec.ft.

February 28

4.41

4.46

4.70

4.94

5.01

4.99

4.94

4.85

4.82

4.83

4.91

4.97

5.02,

5.03

5.04

5.07

5.10

5.19

5.20 

5.22

5.22

5.26

5.25

5.22

114

136

210

310

345

340

315

274

270

265

305

335

360

365

376

393

409

463

475 

487

487

511

505

487

Feet Sec.ft.

March 1

5.27

5.38

5.45

5.47

5.97

6.35

6.52

6.55

6.56

6.64

6.93

6.91

6.75

6.55

6.34

6.26

6.36

6.37

6.28 

6.16

6.00

5.85

5.78

5.77

517

587

640

656

1,070

1,500

1,710

1,750

1,890

2,460

2,960

3,300

3,180

2,990

2,610

2,490

2,640

2,650

2,520 

2,340

2,090

1,880

1,660

1,520

Feet Sec.ft.

March 2

5.74

5.75

5.77

5.77

5.80

5.62

5.91

6.04

6.16

6.42

6.57

6.72

6.83

6.82

6.82

7:i7

7.48

7.55

7.64 

7.70

7.78

8.00

8.30

8.65

1,250

1,160

1,140

1,070

1,010

938

1,019

1,150

1,280

1,590

1,770

1,980

2,140

2,120

2,400

3,150

3,960

4,400

4,910 

5,400

5,960

6,850

8,000

9,450

Feet Sec.ft.

March 3

9.10

9.77

10.18

10.40

10.74

10.45

9.95

9.58

8.97

8.65

6.22

7.98

7.70

7.40

7.10

6.70

6.51

6.26

5.94 

5.68

5.46

5.31

5.17

5.11

11,200

13,100

14,400

15,200

16,400

16,000

15,500

14,900

14,100

13,900

13,300

12,500

11,900

10,900

10,000

9,800

9,600

8,800

8,000 

7,190

6,400

5,800

5,200

4,600

Feet Sec.ft.

March 4

>4.76

U.63

J

4.55

4,300

3,800

3,600

3,400

3,300

3,100

2,920

2,800

2,600

2,500

2,430

2,400

>2,320

U,150

I

4

>2,Q50

1

Supplemental record.- Mar. 3, 5:30 a.m., 10.77 ft., 16,500 sec.-ft.

Santa Margarita River Basin 

Temecula Creek at Nigger Canyon, near Temecula, Calif.

Location.- Water-stage recorder, lat. 33 0 29'40", long. 1160 59'00", in Pauba grant, at 

upper end of Nigger Canyon, a quarter of a mile downstream from Arroyo Seco, and 10 

miles east of Temecula, Riverside County. Altitude, about 1,350 feet.

Drainage area.- Area, 319 square miles. Average altitude, 3,490 feet. Maximum altitude, 6,200 feet. Average slope, 30 percent. Length of main stream channel, 26,5 

miles. Average slope of main stream channel, 3.4 percent.

Gage-height record.- Water-stage recorder graph, except Mar. 4 to 3 p.m. Mar. 6.

Discharge record.- Discharge estimated from hydrograph defined by current-meter 

measurements, gage-height record, and comparison with adjacent stations.

Maxima.- 1938s Discharge, 14,600 second-feet 10 p.m. Mar. 2,(gage height, 11.27 feet). 

1923-37: Discharge, 17,100 second-feet Feb. 16, 1927.

Remarks.- Records poor, due to extreme shifting of channel at high stages. Ho diversions above station. Results of some discharge measurements furnished by Santa 

Margarita Ranch.

454720 O - 42 - 14
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

23

22

35

95

50

28

18

17

20

24

Mar.

180

4,100

3,500

1,300

400

140

125

115

95

90

Apr.

42

39

44

34

30

30

30

30

30

36

Day

11

12

13

14

15

16

17

18

19

20

Feb.

43

79

69

65

62

55

46

41

43

33

Mar.

95

235

195

130

155

115

115

110

30

60

Apr.

37

38

38

36

33

29

28

26

28

27

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

25

21

16

16

16

16

35

50

38.1

2,120

Mar.

60

60

65

62

65

68

55

50

55

48

41

388

23,830

Apr.

27

26

25

23

30

18

17

19

26

30

1,800

Temecula Creek at Railroad Canyon, near Temecula, Calif.

Location.- Water-stage recorder, lat. 33°28'2511 , long. 117°08 I 3511 , in Temecula grant, 

at upper end of Temecula or Railroad Canyon, an eighth of a mile downstream from 

junction with Murrieta Creek, and lj miles south of Temecula, Riverside County. 

Altitude, about 950 feet.

Drainage area.- Area, 592 square miles. Average altitude, 2,663 feet. Maximum altitude, 6,200 feet. Average slope, 26 percent. Length of main stream channel, 41

miles. Average slope of main stream channel, 2.4 percent.

Gage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 9,220 second-feet. Discharge estimated from hydrograph based on current-meter 

measurements and Rage-height record, and by comparison with adjacent stations.

Maxima.-. 1938; Discharge, 21,700 second-feet (estimated) 10 p.m. Mar. 2 (gag'e height, 

 13791 feet).

1923-37: Discharge, about 27,600 second-feet Feb. 16, 1927.

Remarks.- Records poor, due to extreme shifting of channel. Flood flow not affected 

by diversions. Gage-height record and results of discharge measurements furnished 

by Santa Itargarlta Ranch.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

3

9

10

Feb.

18

11

13

27

18

12

11

11

19

23

Mar.

2,620

11,500

3,000

1,700

950

320

250

350

220

190

Apr.

60

59

58

50

51

50

44

41

46

40

Day

11

12

13

14

15

16

17

18

19

20

Feb.

42

46

25

19

15

12

12

13

21

18

Mar.

180

1,810

740

360

290

210

200

160

120

115

Apr.

35

40

61

54

47

31

23

25

25

25

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

16

14

12

12

13

14

130

450

37.4

2,080

Mar.

100

92

98

90

90

90

82

73

78

70

63

1,007

61,910

Apr.

32

29

28

27

35

27

21

27

30

44

39.0

2,320

Santa Margarita River near Fall Brook, Calif.

Location.- Water-stage recorder, lat. 330 24'05", long. IWIS'IO", in sec. 12, T. 9 

S., R. 4 W., 2 miles north of Fall Brook. Altitude, about 3,50 feet.

Drainage area.- Area, 645 square miles. Average altitude, 2,541 feet. Maximum altitude,6,300 feet. Average slope, 33 percent. Length of main etream channel, 50 

miles. Average slope of main stream channel, 2.2 percent.

Sage-height record.- Water-stage recorder graph.

Discharge record.- Discharge estimated from hydrograph based on current-meten measuremerits and gage-height record, and by comparison with adjacent stations.

Maxima.- 1933: Discharge, 28,000 second-feet (estimated) 11 p.m. Mar. 2 (gage height, 

14.0 feet).

1924-37: Discharge, about 33,100 second-feet Feb. 16, 1927.

Remarks.- Records poor, due to extreme shifting of channel. No diversions during 

flood period. Results of discharge measurements furnished by Santa Margarita 

Ranch.
SANTA MAROARITA RIVBR BASIN 201

Mean daily diecharge, in leoond-feet, 1938

Day

1

2

3

4

6

6

7

8

9

10

Feb.

30

23

20

48

30

21

20

22

40

43

Mar.

3,890

12,000

10,400

2,000

1,000

700

400

460

360

320

Apr.

92

92

90

80

79

76

68

66

70

64

Day

11

12

13

14

16

16

17

18

19

20

Feb.

80

88

46

30

26

22

20

22

30

20

Mar.

300

2,140

960

600

460

366.

300

270

240

200

Apr.

66

66

120

88

70

64

64

46

46

44

Day

21

22

23

24

26

26

27

28

29

30

31

Feb.

16

16

16

16

14

13

166

680

83.7

2,980

Mar.

166

166

160

146

140

136

130

126

126

113

110

1,249

76,660

Apr.

60

43

40

37

66

46

37

46

60

100

64.4

3,890

Santa Margarita River at Yaidora, Calif.

Location.- Water-stage recorder, lat. 33 e 14'40n , long. 117*22'60", in Santa Margarita 

'y Los Florei grant, 1 mile downstream from Ysldora, San Diego County, and about 2 

miles upatream from mouth. Altitude, about 15 feet.

Drainage area.- Area, 740 square milea

tude, 8,800 feet. Average elope, 31 percent

milei.

Average altitude, 2,327 feet. Maximum alti-

.wroent. Length of main atreaa channel, 66

Average slope of "main stream channel, 1.7 percent.

Page-height record.- Water-atage recorder graph.

Discharge record.- Diecharge estimated from hydrograph baaed on current-meter measurements and gage-height record, and by comparison with adjacent stations.

Maxima.- 1938t Discharge, 31,000 second-feet (estimated) 1 a.m. Mar. 3, (gage height, 

"' 18.70 feet).

1923-37« Discharge, 33,600 second-feet (estimated) Feb. 16, 1987.

.rice.- Records poor, due to extreme shifting of channel. No diversions during 

Tood period. Oage-helght record and results of discharge measurements furnished 

by Santa Margarita Ranch.

Mean daily discharge, In second-feet, 1938

Day

1

2

3

4

6

6

7

8

9

10

Feb.

44

48

36

61

66

43

36

33

66

60

Mar.

6,270

13,000

16,600

3,000

1,600

1,300

840

900

660

390

Apr.

126

117

111

107

104

101

100

98

96

94

Day

11

12

13

14

16

16

17

18

19

20

Feb.

80

240

100

80

70

60

43

36

60

66

Mar.

360

2,600

1,600

960

690

560

460

340

330

300

Apr.

92

90

126

136

104

88

83

79

76

74

Day

21

22

23

24

26

26

27

28

29

30

31

Feb.

60

40

36

34

30

28

200

976

94.2

6,230

Mar.

236

220

210

206

190

170

200

206

190

160

130

1,730

106,400

Apr.

70

60

77

66

80

80

66

66

60

80

89.7

6,340

Murrieta Oreelc at Temeoula, Calif.

Location.- Water-stage recorder, lat. 33e 29'00", long. 117°08'60", In Temeoula grant, 

o.e mile upstream from debouchment into Temeoula Creek and half a mile south of 

Temeoula, Riverside County. Altitude, about 1,060 feet.

Oral e area.- Area, 220 square miles. Average altitude, 1,710 feet. Maximum altituae, 4,eoO feet. Average slope, 23 percent. Length of main stream channel, 31 

miles. Average slope of main stream channel, 2.1 percent.

Page-height record.- Water-atage recorder graph.

Discharge record.- Discharge estimated from hydrograph based on current-meter measurements and gage-height record, and by comparison with adjacent stations.

Maxima.- 1938: Discharge, 16,800 second-feet (estimated) 8 p.m. Mar. 2 (gage height, 

 B7T feet).

1930-371 Discharge, 7,500 second-feet Feb. 16, 1932.

Remarks.- Records poor, due to extreme shifting of channel. Oage-helght record and 

several discharge measurements furnished by Santa Margarita Ranch.
202 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

.....

Feb.

5.0

4.0

2.8

6.0

4.7

2.8

2.4

2.3

7.0

8.0

t ^

Mar.

1,870

7,200

3,200

360

120

83

62

85

54

40

Apr.

11

9.0

8.5

8.0

7.5

7.5

6.5

5.5

5.5

5.5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

21

24

8.0

4.6

3.9

3^8

3.5

3.5

6.5

4.6

Mar.

33

950

250

105

71

48

45

39

29

25

Apr.

5.0

5.5

7.5

6.5

5.5

5.0

4.9

4.5

4.1

4.0

Day

21

22

23

24

25

26

27

28

29

30

31

Waft wonthly dljrfch&iige, ipf?«#«s8a*£«eti. <..*........,,... -.....''

BowK*, ta (USM-fee*. .....v.«., , f ..>..,,., .,.............:....

Feb.

3.5

3.4

3.2

3.2

3.0

3.0

68

320

" i«;i

1,060

Mar.

22

20

19

17

17

16

15

13

14

14

13

479

89,450

Apr.

4.1

4.0

3.8

3.8

5.0

4.5

4.1

3.8

3.7

5.0

6.SS

MB

San Juan Creek BaaIn

San Juan Creole near San Juan CapiaiywaRj,

Location.- Water-Stage recorder, Iftt. SS'Sft'SO"*, "ltais;*f!t&9&40t--i"is& Mission Vlejo 

grant, at Ortega State Highway Bridge, 2& miles east of San Juan Caplstrano, Orange 

County. Altitude, about 150 feet.

Drainage area.- Area, 110 square miles. Average altitude, 1,470 feet. Maximum altitude, 4,525 feet. Average slope, 30 percent. Length of main stream channel, 18 

miles. Average slope of main stream channel, 4.6 percent.

Sage-hej 

and ]

jtht record.- Water-stage recorder graph except 12 m. Feb. 28 to 2 p.m. Mar. 1 

a a.m. Mar. 2 to 12 m. Mar. 14.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 436 second-feet; peak discharge determined by slope-area measurement. Records 

from 12 m. Feb. 28 to 2 p.m. Mar. 1 and 9 a.m. Mar. 2 to Apr. 30 baeed on currentmeter measurements, slope-area measurement of peak discharge, and comparison with 

record of inflow to Santiago Reservoir.

Maxima.- 1929-37: 1938: Discharge, 13,000 second-feet about 10 p.m. 

Discharge, 8,300 second-feet Feb. 6, 1937.

Mar. 2.

Remarks.- Records poor.

Mean dally discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

18

10

10

14

9

9

9

8.5

8.5

8.5

Mar.

550

4,100

3,400

1,000

600

410

315

265

265

225

Apr.

77

74

71

68

67

63

61

54

53

52

Day

11

12

13

14

15

16

17

18

19

20

Mean monthly discharge, In secondRunoff, In acre-feet. .. i. .........

Feb.

11

47

15

10

8.5

8

7

7. '5

7.5

7

^Mar.

188

600

540

480

410

330

230

195

183

175

Apr.

51

50

50

50

50

47

44

41

38

39

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

7.5

8

8

8

8

8

10

41

11.8 

660

Mar.

170

160

150

139

115

115

112

115

9C

85

80

509 

31,320

Apr.

41

37

38

3,9

41

43

44

45

46

46

50.7 

3,010

Trabuoo Creek near San Juan Caplstrano, Calif.

Location.- Water-stage recorder, lat. 33°31'30", long. 117°40'15", In SW£ sec. 25, T. 

7 S., R. 8 W., at State highway bridge, 1& miles north of San Juan Caplstrano. 

Altitude, 200 feet.

Drainage area.- Area, 36.5 square miles. Average altitude, 1,770 feet. Maximum altltude, 5,680 feet. Average slope, 41 percent. Length of main stream channel, 20 

miles. Average slope of main stream channel, 5.2 percent.

Sage-height record.- Water-stage recorder graph except Mar. 3-4 owing to silting of 

well.

Discharge record.- Stage-discharge relation fairly well defined below 300 second-feet 

by current-meter measurements, and extended above on basis of slope-area determinations. Discharge for Mar. 3 and 4 was obtained by comparison with other streams.

Maxima.- 1938: Discharge, 4,400 second-feet Mar. 2. 

 1930-37: Discharge, 9,240 second-feet Feb. 6, 1937.

Remarks.- Records furnished by Orange County Flood Control District, through M. N. 

Thompson, chief engineer.
ALISO CREEK BASIN 203

Mean daily discharge, in aecond-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.1

0

.1

0

0

0

0

0

0

0

Mar.

254

1,480

820

331

245

195

156

113

92

85

Apr.

33

30

29

27

26

24

23

22

21

20

Day

11

12

13

14

15

16

17

18

19

20

Feb.

0.1

15

4.0

0

0

0

0

0

0

0

Mar.

79

215

211

182

169

152

138

115

103

92

Apr.

19

18

17

16

15

14

14

13

12

11

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

0

15

68

A Mar.

76

64

58

54

51

47

44

40

38

34

33

186

11,440

Apr.

10

10

10

10

27

19

12

- 11

12

22

18.2

1,080

Gage height, in feet, and discharge, in aecond-feet, at indicated time, 1938

tt 

&

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

»

Feet jsec.ft.

February 28

2.68

2.69

2.69

2.69

2.74

2.76

2.78

2.78

2.79

2.80

2.89

3.20

Feet Sec.ft.

March 1

3.18

4.45

4.15

4.47

4.20

4.07

3.95

3.85

3.75

3.46

3.40

3.40

3.36

3.30

3.26

3.22

3.20

3.18

3.16

3.15

3.15

3.15

3.16

3.38

91

720

550

730

580

500

440

390

340

220

180

180

170

140

120

110

95

91

86

84

84

84

86

180

Feet Sec.ft.

March 2

3.30

3.30

3.40

3.80

3.70

3.90

4.12

4.30

4.10

4.65

5.15

6.00

5.80

6.10

6.60

6.85

7.05

7.15

7.30

7.50

7.15

6.70

6.30

6.00

140

. 1'4Q

180

360

320

420

430

640

520

840

1,150

1,700

1,570

1,770

2,130

2,350

2,640

2,910

3,420

4,400

2,910

2,220

1,910

1,700

Feet See. ft.

March 3

5.78

5.5Q

5.31

5.12

4.98

4.80

4.69

4.53

4.42

4.31

4.20

4.12

4.02

3.91

3.86

3.78

3.70

3.65

3.58

3.50

3.47

3.40

3.36

3.32

1,570

1,410

1,300

1,200

1,120

1,030

980

900

840

790

740

710

670

620

600

570

540

520

490

460

460

430

420

400

Feet | Sec. ft.

March 4

/

Allao Creek Baa in 

Aliso Creek at El Toro, Calif.

Location.- Water-stage recorder, lat. 33°37'15", long. 117°41 I 2011 , in Canada de loa

Allsos grant, at Second Street Bridge at El Toro, Orange County. Altitude, 440 feet.

Drainage area.- Area, 8.5 square miles. Average altitude, 997 feet. Maximum altitude, 

2,430 feet. Length of main stream channel, 5 miles. Average slope of main stream 

channel, 7.5 percent.

Gage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined below 300 second-feet by measurements; extended above on basis of slope-area determination.

Maxima.- 1938: Discharge, 1,280 aecond-feet Mar. 2. 

 1930-37: Discharge, 1,950 aecond-feet Feb. 6, 1937.

Remarks.- Records furnished by Orange County Flood Control District, through M. H. 

Thompson, chief engineer.

Mean daily discharge, in second-feet, 1938 

Day

1

2

3

4

5

6

7

8

9

10

Feb.

9

0

.1

.8

0

0

0

0

8

0

Mar.

104

404

66

15

7

2.5

1.0

17

1.0

.7

Apr.

0

0

0

0

0

0

0

0

0

0

Day

11

12

13

14

15

16

17

18

19

20

Feb.

17

7

0

0

0

0

0

0

0

0

Mar.

0.2

46

26

' 7

5

3.0

3.0

3.0

4.0

. 5

Apr.

0

0

0

0

0

0

0

0

0

0

Day

21

22

23

24

25

26

27

28

39

30

31

Feb.

0

0

0

0

0

0

.1

39

2

QQ

161

Mar.

4.0

1.0

0

0

0

0

0

0

0

0

0

Ott A.

1,440

Apr. .

0

0

0

0

3.1

0

0

0

0

0

6
204 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

1~

w

1

2

3

4

5

5

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Oage height, in feet, and discharge, in second-feet, at Indicated time, 1938

FeetJ3eo.ft.

February 27

Feet | Sec. ft.

February 28

4.93

4.96

5.40

5.20

5.52

5.48

5.33

5.28

6.25

5.26

5.27

5.25

5.25

5.25

5.25

5.15

5.02

4.97

5.27

5.60

6.50

7.84

1

> 0.4

1

.1

44

18

54

46

26

18

13

12

11

7

5

5

5

1.0

.5

.1

7

44

180

480

Feet |3eo.ft.

March 1

6.50

9.60

6.90

5.70

5.29

5.08

4.98

4.84

4.74

4.63

4.90

190

1,050

310

100

55

39

36

29

27

23

> 15

56

Feet Sec. ft.

March 2

5.30

5.40

5.15

6.30

6.60

7.70

7.10

7.20

7.30

9.10

8.78

7.60

8.00

8.80

10.30

8.50

6.75

9.30

9.37

6.90

6.50

5.50

5.35

5.40

90

83

32

180

210

420

290

320

350

840

750

440

550

780

1,280

700

260

940

960

290

200

47

28

34

Feet [ 3eo. ft.

March 3

5.35

5.28

5.20

5.20

5.55

8.15

7.00

6.85

6.00

5.55

5.42

5.40

5.38

5.35

5.34

5.34

5.34

5.33

5.32

5.32

5*. 31

5.30

5.30

5.69

27

18

10

9

47

580

290

260

110

44

27

24

21

17

15

14

14

12

10

10

8

6

6

44

Feet |s«o.ft.

March 4

5.90

5,70

5.45

5.39

5.38

Santa Ana River Basin

4, T. 1

Santa Ana River near Mentone, Oalif.

Location.- Water-stage recorder, lat. 34°06 l 40n , long. iWOe'OO", in SWi aeo. . 

S., K. 2 W., near mouth of canyon, 0.4 mile upstream from Mentone power plant of 

Southern California Edison Co., and 3& miles northeast of Mentone. Altitude, about 

1,900 feet.

Drainage area.- Area, 144 square miles (excluding Bear Valley). Average altitude, 6,422 

feet.Maximum altitude, 11,485 feet. Average slope, 42 percent. Length of main 

stream channel, 28 miles. Average slope of main stream channel, 6.4 percent.

gage-height r.eoord.- Water-stage recorder graph except 9 a.m. Mar. 2 to Mar. 23.

Discharge record.- Stage-disoharge relation defined by current-meter measurements below 

900 second-feet prior to Mar. 2 and below 400 second-feet after Mar. 23. Maximum 

disoharge by slope-area method. Diecharge for maximum 24 hours determined from 

rainfall-runoff relation, using the records from recording rain gages at Devils 

Canyon and Del Rosa as a basis for distribution of the storm rainfall; discharge for 

Mar. 2-22 obtained by comparison with adjacent streams.

Maxima.- 1938: Disoharge, 52,300 second-feet about 7 p.m. Mar. 2.

 1596-1937: Disoharge, 29,100 second-feet Jan. 27, 1916, by slope-area method.

Remarks.- Records fair except those for Mar. 2-23, which are poor. Practically no release from Bear Valley Reservoir during flood period. Disoharge is for natural flow 

of the stream and includes flow in Southern California Bdison Co.'s canal and Greenspot pipe line; no flow in canal and pipe line Feb. 28 to Apr. 30.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

72

64

90

277

105

85

64

61

78

108

Mar.

979

15,500

8,080

2,550

1,550

1,000

800

670

600

550

Apr.

248

250

255

266

271

259

250

246

 250

255

Day

11

12

13

14

15

16

17

18

19

20

Feb.

119

207

126

108

86

76

75

67

100

85

Mar.

500

1,240

1,970

1,150

760

580

480

430

390

370

Apr.

2^4

250

280

255

250

248

257

268

330

379

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

70

71

71

62

63

63

129

611

114

6,330

Mar.

355

345

342

340

321

304

297

285

285

286

253

86,400

Apr.

431

440

424

400

379

338

352

352

355

347

18,150
SAHTA ANA RIVER BASIN

Oage height, In feet, and discharge, In second-feet, at Indicated time, 1938

Hour

 1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 28

2.76

2.90

3.05

3.10

3.16

3.40

3.70

3.95

4.00

3.95

3.95

3.88

3.82

3.72

3.68

3.65

3.62

3.58

3.56

3.54

3.52

3.50

3.50

3.75

343

385

438

455

476

530

690

815

840

815

815

770

730

674

650

630

618

602

594

586

578

570

570

670

Feet | Sec. ft.

March 1

4.15

5.60

5.70

5.75

5.70

5,50

5.00

4.80

4.70

4.50

4.36

4.25

4.12

4.00

3.90

3.85

3.80

3.78

3.76

3.73

3.71

3.69

3.66

3.65

865

1,650

1,720

1,760

1,720

1,580

1,280

1,160

1,100

990

920

865

800

740

690

670

650

642

634

622

614

606

594

590

Feet Sec. ft.

March 2

3.62

3.60

3.59

3.58

3.59

3.65

3.92

4.15

4.45

578

570

566

562

566

590

700

815

965

Santa Ana River near Prado, Calif.

Location.- Water-stage recorder, lat. 33°52'0511 , long. 117°40'2011 , In Lomas de Santiago 

grant , at Riverside-Orange County line, In lower Santa Ana Canyon, 3 miles downstream from Rlncon bridge, and 3 miles southwest of Prado, Riverside County. Altitude, about 400 feet.

Drainage area.- Area, 1,520 square miles (excluding Bear Valley and San Jacinto River). 

Average altitude, 2,494 feet. Maximum altitude, 11,485 feet. Average slope, 28 

percent. Length of main stream channel, 66.7 miles. Average slope of main stream 

channel, 3.1 percent.

Sage -height record . - Water-stage recorder graph except 4 p.m. Mar. 2 to Mar. 29. Staff 

gage read 6 to 10 times dally Mar. 9-29.

charge record.- Stage-discharge relation defined by current-meter measurements below

3,000 second-feet and extended above on basis of mean depth-mean velocity relation. 

Maximum discharge obtained from studies of results of slope-area determinations, 

mean depth-mean velocity relation, and a cross section made Mar. 5, 1938, together 

with comparison with maximum discharge of Santa Ana River at Santa Ana (see pp. 18S-183). 

Discharge for some periods estimated by comparison with Santa Ana River at Santa Ana.

Maxima.- 1938: Discharge, about 100,000 second-feet at 12:15 a.m. Mar. 3 (gage height, 

 17732 feet).

1919-37: Discharge, about 18,000 second-feet Feb. 16, 1927.

Remarks.- Records fair, except for the period Mar. 2-20, which are poor. Ho diversions 

during flood period. Slight regulation at Bear Valley Reservoir.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

186

146

130

170

144

110

108

106

162

196

Mar.

1,750

12,300

28,600

4,480

1,900

1,280

1,020

780

570

440

Apr.

326

290

295

290

302

326

295

235

199

224

Day

11

12

13

14

15

16

17

18

19

20

Feb.

195

324

180

149

141

132

128

128

146

132

Mar.

400

3,020

5,210

3,500

2,800

1,100

1,300

1,300

890

610

Apr.

240

272

302

29d

313

302

277 .

272

302

350

.

Day

21

22

23

24

25

26

27

28

29

30

31

Runoff, In acre-feet .........................................

Feb.

128

125

125

125

118

118

176

345

8,670

Mar.

480

430

410

410

420

410

410

400

380

470

450

154,600

Apr.

395

456

485

522

616

529

420 -

400

390

413

344

20,490
206 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Sage height, In feet, and discharge, In second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec. ft.

February 28

> 2.30

V

2.58

3.25

> 247

i

> 334

1

1

1

> 648

1

Feet Sec. ft.

March 1

3.60

4.25

3.82

3.55

3.65

3.95

4.20

4.65

4.70

4.65

4.70

4.75

5.00

5.50

6.00

6.00

6.20

6.00

5.35

4.65

4.20

3.90

3.55

3.35

870

1,360

1,030

840

905

1,120

1,320

1,620

1,760

1,620

1,760

1,810

2,070

2,650

3,300

3,300

3,600

3,300

2,470

1,720

1,320

1,090

840

720

Feet Sec.ft.

March 2

3.20

3.05

3.00

2.90

3.10

4.00

4.70

5.25

5.60

6.20

6.90

8.00

9.20

9.90

10.20

10.40

630

555

530

480

580

1,160

1,760

2,350

2,780

3,600

4,700

6,850

9,800

11,700

12,800

13,400

Santa Ana River at Santa Ana, Calif.

Location.- Water-stage recorder and concrete weir control, lat. 33°45 I 001', long. 117° 

54'20", in Las Bolsas land grant, an eighth of a mile above Fifth Street Bridge In 

Santa Ana, Orange County, and 2 miles below junction with Santiago Creek. Altitude, 

about 80 feet.

Sage-height record.- Water-stage recorder graph except Mar. 3-6 and Apr. 18-30, when 

stilling well was filled with silt.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 10,000 second-feet; extended to peak discharge determined by slope-area method. 

Discharge 7 a.m. Mar. 3 to Mar. 6 based on comparison with Santiago Creek at Santa 

Ana and current-meter measurements.

Maxima.- Fee~t). 1938: Discharge, 46,300 second-feet about 3 a.m. Mar. 3 (gage height, 10.2 

1923-37: Discharge, about 25,000 second-feet Feb. 16, 1927.

Remarks.- Records fair, except those for Mar. 3-6, which are poor. No diversions during flood period. Some regulation at Bear Valley and Santiago Creek Reservoirs.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

14

0

0

0

0

0

0

0

87

6

Mar.

991

8,590

20,300

5,070

2,100

1,500

1,370

920

470

300

Apr.

57

52

51

52

53

54

54

53

53

68

Day

11

12

13

14

15

16

17

18

19

20

Feb.

32

82

15

1.7

.3

.2

.1

3.0

30

28

Mar.

250

2,700

5,710

3,660

2,770

1,020

1,200

1,100

700

400

Apr.

71

70

68

64

60

56

52

45

41

39

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

10

0

0

0

1.0

.2

23

74

808

Mar.

350

200

180

170

170

160

150

140

110

80

60

2,029

124,700

Apr.

37

36

34

33

31

30

29

28

27

25

47.4

2,860
SANTA ANA RIVER BASIN 207

Oage height, in feet, and discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Seo.ft.

February 28

0.68

.65

.70

.80

.90

1.05

1.30

1.22

1.22

1.10

1.02

.94

.82

.77

.74

.80

.77

.74

.68

.68

.72

.78

1.00

1.50

18

16

21

33

53

90

194

158

158

109

84

64

46

44

43

55

48 ' 46

36

36

46

59

95

420

Feet Seo.ft.

March 1

1.70

2.10

2.30

2.30

2.22

2.15

2.00

1.90

1.75

1.65

1.60

1.65

1.77

1.80

1.80

1.80

1.78

1.88

2.10

2.14

2.20

2.22

2.20

2.05

700

900

1,270

1,270

948

800

540

420

275

206

176

206

388

420

540

540

668

984

1,750

2,210

2,450

2,530

2,450

1,880

Feet | Seo.ft.

March 2

1.92

1.78

1.70

1.65

1.68

2.00

2.40,

2.70

2.72

2.85

3.25

3.40

3.60

3.90

4.40

4.80

5.00

5.20

5.30

5.40

5.60

5.70

6.00

6.40

1,460

1,090

900

800

860

1,700

3,200

4,350

4,430

4,950

6,500

7,100

7,900

9,100

11,400

13 ,300

14,300

15,200

15,700

16,200

17,200

17,700

19,200

21,400

Feet SeoN.ft.

March 3

6.60

8.0

10.2

9.0

8.5

8.0

22,500

30,400

46,300

36,600

33,400

30,400

Mill Creek near Craftonville, Calif.

Location.- Water-stage recorder and concrete control, lat. 34°05 I 1511 , long. 117°02' 

25lt , in NEi sec. 13, T 1 S., R. 2 W., at mouth of canyon, below bridge on RedlandsBear Valley highway, and 5 miles northeast of Craftonville. Altitude, 2,950 feet.

Drainage area.- Area, 42.9 square miles. Average altitude, 6,805 feet. Maximum

altitude, 11,480 feet. Average slope, 41 percent. Length of main stream channel, 

12.6 miles. Average slope of main stream channel, 11 percent.

Sage-height record.- Record lost with the destruction of recorder shelter and oontrol on Mar. "57

Discharge record.- Maximum discharge obtained by slope-area method. Discharge for

maximum 24-hour period determined from rainfall-runoff relation using the Del Rosa 

, recording rain gage as a base for distribution of total storm precipitation. The 

remainder of the period was determined by comparison with records for Santa Ana 

River near Mentone.

Maxima.- 1938: Discharge, 18,100 second-feet Mar. 2.

1919-37: Discharge, 4,500 second-feet (estimated) Feb. 16, 1927.

Remarks.- Records poor. Discharge is for natural flow of the stream and includes 

flow in Mill Creek power canals Nos. 1, 2, and 3; no flow in canals Mar. 3 to 

Apr. 30.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

31

31

32

45

38

34

31

30

34

36

Mar.

346

6,300

2,820

1,080

920

690

580

580

460

350

Apr.

138

138

136

136

136

137

139

140

142

146

Day

11

12

13

14

15

16

17

18

19

20

Feb.

38

46

43

37

35

32

32

31

35

32

Mar.

350

360

570

350

240

200

180

170

160

155

Apr.

148

150

152

156

158

158

160

160

158

155

Day

21

22

23

24

25

26

27

28

29

50

31

Feb.

31

30

31

31

30

30

36

216

2,260

Mar.

152

150

148

146

145

144

142

140

140

140

140

36,590

Apr.

152

150

146

144

142

140

139

136

135

135

145

8,650
208 FLOODS OF MARCH 1936 IN SOUTHERN CALIFORNIA

Plunge Creek near Bast Highlands, Calif.

Location.- Water-stage recorder, lat. 34C 07'10", long. 117°08'30", In NB&NB& sec. 1, T.

18., R. 3 W., at mouth of oanyon at crossing at North Fork ditch siphon, 2 miles

northeast of East Highlands. Altitude, about 1,625 feet.

Dral ea.- Area, 16.9 square miles. Avsrage altitude, 4,036 feet. Maximum alti-

. 5,350 feet. Average slope, 38 percent. Length of main stream channel, 7.5 

miles. Average slope of main stream channel, 12 percsnt.

Qage-helgbt record.- Water-stage recorder graph except Mar. 3-11.

Dischargerecord.- Stage-discharge relation defined by current-meter measurements below 300 ssoond-feet; extended to 2,900 second-feet on basis of mean depth-mean 

velocity relation. Maximum discharge determined by slope-area method and checked 

by,rainfall-runoff study. Discharge for the maximum 24 hours determined,by rainfallrunoff studies; the rainfall was distributed on the basis of the Del Rosa recording 

rain gags record. Discharge Mar. 1-11 based on gage height, rainfall-runoff study, 

and comparative hydrographs.

Maxima.- 1938: Discharge, 5,340 second-feet about 6 p.m. Mar. 2 (gage height, 7.0 

feet).

1919-37: Discharge, 1,420 second-feet Feb. 16, 1927 (gage height, 3.8 feet).

Remarks.- Records good, except those fcr Mar.1-23, which are poor.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

22

17

35

75

27

15

11

9.5

14

17

Mar.

219

1,500

1,130

413

240

162

110

87

74

67

Apr.

32

31

28

26

- 27

23

20

18

17

16

Day

11

12

13

14

15

16

17

18

19

20

Feb.

36

53

31

23

20

16

14

13

26

16

Mar.

62

174

189

126

100

84

73

67

61

55

Apr.

13

12

32

24

20

19

16

15

14

14

Day

21

22

23

24

25

26

27

28

29

30

31

Runoff, in acre-feet. ........................................

Feb.

15

14

13

12

10

10

29

167

onr o

1,510

Mar.

53

50

45

46

44

42

42

40

42

38

33

1*7 A

10,850

Apr.

12

13

11

16

32

23

19

17

23

30

20.4

1,220

Gage height, in feet, and discharge, in second-feet, at Indicated time, 1958

a

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10 

11

M

Feet See. f.tFebruary 27

>0.73

>1.00

>1.40

1

> 14

LOD

] Ui91

Feet Sec.ft.

February 28

1.72

1.72

1.71

1.69

1.75

1.98

2.07

2.09

2.06

1.96

1.92

1.87

1.90

1.94

1.91

1.86

1.82

1.77

1.72

1.69

1.67

1.66 

1.80

2.15

144

144

142

138

150

193

211

215

209

193

182

172

178

186

180

170

163

153

144

136

135

133

159

228

Feet Sec.ft.

March 1

3.00

3.40

3.00

2.66

2.50

2.35

2.20

2.12

2.02

2.00

1.96

1.90

1.85

1.80

1.75

1.73

1.71

1.70

1.67

1.64

1.62

1.60 

1.58

1.56

435

555

435

346

305

271

238

221

201

197

189

178

169

159

150

146

142

140

135

130

126

123

119

116

Feet Sec.ft.

March 2

1.56

1.62

1.62

1.63

1.70

2.00

2.30

2.70

2.84

3.10

3.60

116

126

126

128

140

197

260

355

393

465

620

Feet See.ft.

March 3

Feet See.ft.

March 4 '

Supplemental record.- Mar. 1, 1:30 a.m., 605 see.-ft.
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to 

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to

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?

o 

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sV

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a

«

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?

rtR 

g

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act1

l-«

s00

%* 

is

?g

»*4

 4 »

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oo

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210 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Warm Creek near Colton, Calif.

Location.- Water-stage recorder, lat. 34°04'0011 , lonS- 117C 18'30", In San Bernardlno 

grant, at Colton Avenue Bridge, 1-J miles east of Colton, San Bernardlno County. 

Altitude, about 970 feet.

Page-height record.- Water-stage recorder graph prior to 6 a.m.-Mar. 2.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 1,250 second-feet. Discharge 6 a.m. Mar. 2 to Apr. 30 based on comparative 

hydrograph and five discharge measurements.

Maxima. 

1

.- 1938: 

920-37:

Discharge, 27,500 second-feet 7 p.m. Mar. 2. 

Discharge, 2,780 second-feet Dec. 21, 1921.

Remarks.- Records fair. Discharge Is for natural flow of stream and Includes flow In 

Meeka and' Daley canal; flow In canal Feb. 1-28 and Mar. 6 to Apr. 30 was 0.1 secondfoot or less and did not affect flood flow.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

98

36

77

172

36

36

36

35

55

34

Mar.

666

10,225

5,715

925

490

349

277

239

214

194

Apr.

101

102

103

104

105

107

108

109

110

109

Day

11

12

13

14

15

16

17

18

19

20

Feb.

112

94

61

53

47

47

45

47

53

44

Mar.

185

329

413

308

220

170

138

116

101

94

Apr.

108

107

1C6

105

104

102

101

100

99

98

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

45

45

46

45

44

45

105

448

4,050

Mar.

88

86

85

87

89

92

94

95

97

99

100

44,390

Apr.

97

96

95

94

93

91

90

88

87

85

100

5,960

Discharge, In second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

49

50

50

50

50

50

50

55

70

120

160

240

150

100

92

90

91

93

104

114

156

194

220

204

Feb. 28

184

163

157

163

224

305

370

488

498

407

416

524

750

822

828

768

641

562

524

486

377

354

349

522

Mar. 1

652 850'

1,140

1,260

1,360

1,270

1,130

975

853

782

702

637

572

494

434

352

316

270

254

237

232

228

226

225

Mar. 2

225

225

225

225

253

543
SANTA ANA RIVER BASIH 211 

Strawberry Creek near Arrowhead Springs, Calif.

location.- Water-stage recorder and broad-crested weir control, lat. 34°t0'45", long. 

Il7"15'55", In SEj sec. 11, T. 1 N., R. 4 W., upstream from Del Rosa Water Co.'s 

lower diversion dam, and half a mile south of Arrowhead Springs. Altitude, about 

1,650 feet.

Drainage area.- Area, 8.6 square miles. Average altitude, 3,520 feet. Maximum altitude, 6,150 feet. Average slope, 47 percent. Length of main stream channel, about 

4.8 miles. Average slope of main stream channel, 18 percent.

Gage-height record.- Water-stage recorder graph except 12 m. Mar. 2 to Mar. 15.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

500 second-feet; extended above on the basis of mean depth-mean velocity relation 

and levels of March 1938 and confirmed by rainfall-runoff data. Maximum discharge 

estimated by consideration of slope-area studies, rainfall-runoff studies, and 

knowledge of local conditions. Records for maximum 24 hours derived by rainfallrunoff study, using Del Rosa recording rain gage as a base for distribution of total 

storm precipitation.

Maxima.- 1938: Discharge, 3,360 second-feet 4 p.m. Mar. 2 (gage height, 5.30 feet). 

1919-37: Discharge, 492 second-feet Feb. 6, 1937 (gage height, 4.15 feet).

Remarks.- Records good except those for 12 m. Mar. 2 to Mar. 15, which are poor.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

12

6.5

26

50

19

12

9

8

14

12

Mar.

106

792

414

132

76

62

55

51

39

34

Apr.

22

20

20

20

21

19

18

17

17

17

Day

11

12

13

14

15

16

17

18

19

20

Feb.

13

18

14

11

10

9

8

8

11

8.5

Mar.

34

148

206

92

63

55

49

44

42

39

Apr.

17

18

22

19

17

16

16

14

14

14

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

7.5

7

6.5

6

5.5

5.5

12

63

14.0

778

Mar.

35

34

31

29

28

26

26

26

26

24

22

Ql A

5,630

Apr.

14

14

13

16

22

18

16

14

21

26

17.7

1,060

Cage height, in feet, and discharge, in second-feet, at indicated time, 1958

I

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec. ft.

February 27

1.54

1.57

1.67

1.85

1.85

2.27

5.5

6

8

14

14

42

Feet Sec. ft.

February 28

2.25

2.32

2.28

2.20

2.30

2.31

2.43

2.44

2.36

2.36

2.48

2. 62

2.62

2.70

2.74

2.60

2.54

2.46

2.43

2.40

2.39

2.42

2.80

3.14

40

47

42

35

35

45

56

57

49

49

62

81

81/

93

98

77

68

59

55

52

51

54

108

181

Feet Sec. ft.

March 1

3.50

3.55

3.28

3.10

3.02

2.95

2.85

2.79

2.72

2.66

2.59

2.56

2.54

2.50

2.48

2.43

2.41

2.38

2.36

2.34

2.32

2.29

2.28

2.27

275

295

223

175

157

146

115

111

99

89

78

74

71

66

63

58

55

52

50

48

46

43

42

41

Feet Sec. ft.

March 2

2.27

2.31

2.33

2.36

2.52

2.74

3.14

3.35

3.50

3.75

4.00

4.10

42

46

48

49

69

103

180

250

310

425

580

740

Feet Sec. ft.

March 3

-

Feet See. ft.

March 4
212 FLOODS OF J1AROH 1938 IN SOUTHERN CALIFORNIA

Waterman Canyon Creek near Arrowhead Springs, Calif.

Location.- Wate'r-stage recorder and broad-crested weir control, lat. 34C 11'35", long. 

117u l6'35", In SWtSWi sec. 2, T. 1 N., R. 4 W., 600 feet upstream from old toll

house, and 1 mile northwest of Arrowhead Springs. Altitude, about 8,125 feet.

Dral me area.- Area, 4.55 square miles 

ie, 5,400 feet. '

Average altitude, 3,620 feet. Maximum altiAverage slope, 50 percent. Length of main stream channel, 4.5 

milos. Average slope of main stream channel, 14 percent.

gage-height record.- Water-stage recorder graph, e.xcept 10 a.m. Mar. 2 to Mar.. 15.

Discharge record.- Stage-discharge relationship defined by current-meter measurements 

below 100 second-feet and extended to 500 second-feet on basis of mean depth-mean 

velocity relation. Oonorete control was destroyed during afternoon of Mar. 2. 

Maximum discharge estimated by consideration of slope-area studies, rainfall-runoff 

studies, and knowledge of local conditions. Discharge for the maximum 24-hour 

period determined from rainfall-runoff study, using the Del Rosa, Etiwanda, and 

Devil Canyon recording rain gage records as a basis for distribution of total storm 

precipitation. Discharge for the remainder of the period, Mar. 2-15, determined 

from retention study and comparison with nearby stations.

Maxima.- 1938s. Discharge, 2,350 second-feet about 4 p.m. Mar. 2.

1919-37! Discharge, 390 second-feet Feb. 6, 1937 (gage height, 4.10 feet).

Remarks.- Records good, except for the period Mar. 2-15, which are poor, 

small diversions for domestic supply above station.

Several

Mean daily discharge, In seoond-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

IS

3.1

26

21

7

5.5

4.8

4.3

2.9

1.3

Mar.

55

478

156

74

51

41

35

32

30

29

Apr.

12

12

11

11

12

11

11

10

10

10

Bay

11

IS

13

14

15

16

17

18

19

20

Feb.

8.7

11.5

8.5

6.5

5.5

5.5

4.8

5.5

6.5

4.8

Mar.

29

109

111

63

48

43

42

36

35

34

Apr.

9.5

10

12

10

9.5

9

9

8.5

8.5

8.2

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

4.5

4.3

3.8

3.8

3.6

3.4

13

38

B oo

456

Mar.

31

29

27

S5

S3

20

19

17

17

15

14

57.1

3,510

Apr.

7.5

7

7

8.5

12

9

8.5

9

10

9

9

rjn

579

Page height, in feet, and discharge, in seoond-feet, at indicated time, 1988

s

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet aeo.ft.

February 37

2.78

2.78

2.79

2.79

2.79

2.80

2.82

2.83

2.85

2.90

2.94

2.94

2.99

3.04

3.01

2.96

2« 93

2! 95

2.98

3.04

3.15

3.17

3.14

3.14

3.4

3.4

3.6

3.6

3.6

3.8

4.3

4.5

5

6.5

9

9

13

18

15

11

8.5

10

12

18

33

36

31

31

Feet Sec. ft.

February 28

3.15

3.12

3.09

3.15

3.23

3.21

3.15

3.13

3.33

3.34

3.37

3.36

3.35

3.32

3.20

3.18

3.16

3.13

3.16

3.18

3.26

3.50

3.50

33

27

SI

31

42

38

S7

24

60

62

68

65

62

51

25

22

20

15

15

17

18

-29

88

82

Feet See. ft.

March 1

3.65

3.70

3.47

3.51

3.52

3.51

3.52

3.50

3.50

3.50

3.49

3.48

3.47

3.46

3.45

3.44

3.43

3.42

3.40

3.41

3.43

3.41

3.40

3.37

120

134

60

65

65

62

62

57

57

57

54

51

49

46

44

42

40

38

35

36

40

36

35

29

Feet jseo.ft.

March 2

3.37

3.37

3.39

3.49

3.50

3.56

3.59

3.63

3.85

29

29

34

69

86

120

154

199

308

Feet See. ft.

March 3

Feet See. ft.

March 4
SANTA ANA RIVER BASIN 213

City Greek near Highland, Calif.

Location.- Water-stage recorder and concrete control, lat. 34°08 I 201', long. 117°11 I 251', 

in HW±SWi sec. 27, T. 1 N., R. 3 W., li miles northeast of Highland. Altitude, about 

1,520 feet.

Drainage area.- Area, 19.3 square miles. Average altitude, 3,330 feet. Maximum altitude, 6,350 feet. Average slope, 47 percent. Length of main stream channel, 7.6 

miles. Average slope of main stream channel, 12 percent.

Page-height record.- Water-stage recorder graph except 12 m. Mar. 2 to Mar. 11.

Discharge record.- Stage-discharge relation defined by current-meter measurements below , 

250 second-feet; extended to peak discharge determined by slope-area method. Discharge for the maximum 24 hours determined from rainfall-runoff relation, using the 

Del Rosa recording rain -gags record as a base for distribution of total storm prscipitation. Discharge Mar. 2-11 determined from retention study and comparison with 

adjacent stations.

Maxima.- 1938: Discharge, 6,900 second-feet 4 p.m. Mar. 2. 

1919-37: Discharge, 2,360 second-feet Apr. 5, 1926.

Remarks.- Records good except those for Mar. 2-10, which are poor. Discharge is for 

natural flew of the stream and includes flow in City Oreek Water Oo.'s canal.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

23

14

33

97

45

27

20

16

25

26

Mar.

255

i;990

738

264

208

160

144

96

80

78

Apr.

43

43

42

41

42

38

. 36

34

33

32

Day

11

12

13

14

15

16

17

18

19

20

Feb.

36

52

35

28

24

20

16

16

22

19

Mar.

74

338

491

336

240

194

1S5

126

108

96

Apr.

32

32

44

36

35

34

32

30

28

23

Day

21

22

23

24

26

26

27

23

29

30

31

Feb.

17

15

14

13

12

12

26

170

31.2

1,730

Mar.

86

78

70

64

60

55

54

54

58

61

46

221

13,580

Apr.

27

27

26

28

40

34

31

23

32

42

2,040

Discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

«

7

3

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

> 13

> SO

> 55

Feb. 23

103

103

104

107

107

124

166

186

182

175

177

186

205

230

228

224

208

196

177

168

168

157

206

290

Mar. 1

397

661

529

450

357

328

299

279

261

242

224

210

196

182

169

160

152

148

143

136

133

125

122

118

Mar. 2

122

126

128

130

147

251

322

427

600

741

1,100

2,600
214 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Devil Canyon Creek near San Bernardino, Calif.

Location.- Water-stage recorder and concrete control, lat. 34°12'05", long. 117°20'10", 

"in Muscuplabe grant, 7.3 miles northwest of San Bernardino, San Bernardino County. 

Altitude, about 1,800 feet.

Drainage area.- Area, 6.16 square miles. Average altitude, 3,560 feet. Maximum altituae, 5,350 feet. Average slope, 42 percent. Length of main stream channel, 4.5 

miles. Average slope of main stream channel, 13 percent.

Page-height record.- Water-stage recorder graph except 2 p.m. Mar. 2 to Mar. 7.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

80 second-feet; extended logarithmically to 600 second-feet. Stream divided above 

station during storm period, only part of the flow passing gage (data in table includes both channels). Maximum discharge estimated by consideration of slope-area 

studies, rainfall-runoff studies, and knowledge of local conditions. Discharge for 

the maximum 24 hours determined from rainfall-runoff study, using the recorde from 

the recording rain gages at Del Rosa, Etiwanda, and Devil Canyon to determine 

distribution of total storm rainfall.

Maxima.- 1938: Discharge, 3,320 second-feet about 4 p.m. Mar. 2.

1913-14, 1919-37! Discharge, 220 second-feet Apr. 7, 1926.

Remarks. - Records good except for the period Mar. 2-11, which are poor. City of San/ 

Bernardino diverts water above gage. There was no diversion during period of flood 

flow.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.1

.1

5.5

15.0

8.0

5.5

3.3

1.3

2.2

2.4

Mar.

48

495

359

137

60

46

40

36

34

32

Apr.

21

21

20

19

20

19

18

16

15

15

Day

11

12

13

14

15

16

17

18

19

20

Feb.

3.9

7

5.5

4.0

2.2

1.5

1.0

1.3

2.1

1.8

Mar.

31

143

141

70

50

48

48

44

42

39

Apr.

14

15

17

15

13

13

12

11

11

11

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

1.6

1.4

1.0

' .8

.7

.6

1.0

32

4.03

224

Mar.

37

36

33

32

29

28

27

25

25

23

23

4,480

Apr.

11

10

12

14

21

14

14

' .13

14

16

902

Page height, in feet, and discharge, in second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10 '11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec.ft.

February 28

2.00

2.04

2.10

2.23

2.38

2.46

2.51

2.51

2.52

2.55

2.66

2.75

2.82

2.82

2.82

2.78

2.75

2.73

2.70

2.68

2.67

2.71

2.83

2.92

8.5

9

11

14

19

28

24

24

25

27

35

43

51

51

51

45

42

40

' 37

35

34

36

47

57

Feet Sec.ft.

March 1

3.00

3.07

3.17

3.12

3.07

3.02

2.99

2.91

2.90

2.87

2.82

2.78

2.75

2.74

2.73

2.71

2.70

2.68

2.67

2.66

2.66

2.65

2.64

2.63 '

65

77

90

80

72

67

63

53

52

49

44

39

37

36

36

34

33

32

31

30

30

29

29

28

Feet | Sec.ft.

March 2

8.65

8.65

2.66

2.67

2.72

2.85

3.02

3.14

3.18

3.35

3.37

3.50

29

29

30

31

35

46

67

83

90

118

130

150

250

1,300
SANTA ABA RIVER BASIN 215

Lytle Creak near Fontana, Calif.

Location.- Two water-stage recorders, lat. 34°12'05", long. 117°26'50", in HWi sec. 6, 

5. IN., R. 5 W. (unsurveyed), a quarter of a mile below Lytle Creek power plant of 

Southern California Edison Co., and 7j miles north of Fontana. Altitude, about 

2,200 feet.

Drainage area.- Area, 47.9 square miles. Average altitude, 6,038 feet. Maximum altitude, 10,080 feet. Average slope, 45 percent. Length of main stream channel, 15.7 

square miles. Average slope of main stream channel, 9.4 percent.

gage-height record.- Graphs from two water-stage recorders of little value due to 

Inability to confine flow to channel near gages.

Discharge record.- Maximum discharge determined by slope-area measurement. Discharge 

ror the maximum 24 hours determined from rainfall-runoff studies, using the records 

from the recording rain gages at Camp Baldy and Etiwanda as a basis for distribution 

of the rainfall. Rainfall-runoff relation based on the record of Fern Canyon 

Watershed No. 2. The remainder of the record determined by current-meter measurements and daily estimates of flow made by the Fontana Union Water Co.

Maxima.- 1938: Discharge, 25,200 second-feet about 5 p.m. Har. 2.

1918-21, 1922-37: Discharge, about 5,300 second-feet Feb. 16, 1927.

Remarks.- Records poor. Discharge is for natural flow of the stream and includes flow 

in Fontana pipe line} no flow in pipe line Mar. 3-9.

Mean daily discharge, in second-feet, 1988

Day

1

2

3

4

5

6

7

8

9

10

Feb.

67

41

268

268

82

60

53

50

83

72

Mar.

1,020

8,96C

2,330

1,080

 83

692

600

550

550

502

Apr.

191

191

189

187

184

180

172

173

169

168

Day

11

12

13

14

15

16

17

18

19

20

Feb.

156

130

89

65

72

67

56

58

 58

60

Mar.

714

944

805

436

361

289

284

254

322

301

Apr.

168

166

166

164

164

160

156

153

151

152

Day

21

22

23

24

25

26

27

2829'

30

31

Feb.

56

54

54

51

49

49

156

830

6,300

Mar.

274

258

257

244

232

221

211

197

186

191

193

785

48,280

Apr.

155

158

160

161

175

177

168

174

178

184

170

10,100

Lytle Creek (east channel) at San Bernardlno, Calif.

Location.- Water-stage recorder, lat. 34°-05 l 50", long. 117°19 t 05", in San Bernardino 

grant, near Atchlson, Topeka & Santa Fe Railway bridge, a quarter of a mile upstream from lit. Vernon Street Bridge, at San Bernardlno, San Bernardlno County. 

Altitude, about 1,050 feet.

Page-height record.- Water-stage recorder graph prior to 3 a.m. Mar. 1.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 1,500 second-feetj.peak discharge determined by contracted-opening method. Discharge 3 a.m. Mar. 1 to liar. 4 obtained by comparison with Lytle Creek at Fontana, CaJon and Lone Pine Creeks near Keenbrook, and west channel of Lytle Creek at Colton, 

and liar. 4 to Apr. 30 by comparison with dally discharge of Lytle Creek at Foothill 

Boulevard (about 1 mile upstream) as furnished by the Fontana Water Co., and station on Warm Creek.

Maxima.- 1938t 1929-37: Discharge, 21,500 second-feet 7t3C p.m. Mar. 2. 

Discharge, 1,060 second-feet, Feb. 14, 1937.

Remarks.- Records poor.

4S4720 O - 42 - 15
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Mean daily discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

18

1.0

91

167

4.3

2.8

.5

.1

.7

2.2

Mar.

604

7,640

4,460

625

228

160

100

68

44

27

Apr.

20

19

18

17

17

17

17

17

19

20

Day

11

12

13

14

15

16

17

18

19

20

Feb.

77

41

3.8

.3

0

0

0

0

0

0

Mar.

32

103

119

74

54

56

43

38

27

12

Apr.

23

25

27

28

29

28

27

26

27

28

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

2.7

255

1,320

Mar.

24

20

22

27

30

33

34

33

30

. 26

22

29,390

Apr.

28

29

28

26

25

27

32

39

47

64

26.5

1,560

Discharge, In second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

February 87

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

6

18

24

36

February 28

50

50

50

50

50

70

140

220

200

190

350

600

940

860

650

450

320

210

16S

130

105

95

98

100

March 1

110

950

1,350

Lytle Creek (west channel) at Ccltcn, Calif.

Location.- Water-stage recorder, lat. 34°04 I 00B , long. 117°19 I 15", in San Bernardlno 

grant, at F Street near Colton Avenue, at Colton, San Bernardlno County. Altitude, 

about 980 feet.

Sage-height record.- Water-stage recorder graph except 2 p.m. Mar. 2 to 4 p.m. Mar. 3, 

and 5 a.m. Mar. 4 to Mar; 15.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 480 second-feet; extended logarithmically to peak stage. Records for periods of 

missing gage heights obtained from peak discharge computation and by comparison with 

east channel of Lytle Creek.

Maxima.- 1938: Discharge, 7,900 second-feet 7 p.m. Mar. 2. 

1929-37: Discharge, 20 second-feet Jan. 5, 1935.

Remarks.- Records fair except 2 p.m. Mar. 2 to 4 p.m. Mar. 3, and 5 a.m. Mar. 4 to 

Mar. 15, which are poor. Flood flow not affected by diversions.

Mean dally discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.6

0

.1

.1

0

0

0

0

.6

0

Mar.

6.2

2,180

817

27

1.6

.4

0

0

0

0

Apr.

0

0

0

0

0

0

0

0

0

0

Day

11

12

13

14

15

16

17

18

19

20

Mean monthly discharge, in second

Feb.

0.1

0

0

0

0

0

0

0

0

0

Mar.

0

0

0

0

0

0

0

0

0

0

Apr.

0

0

0

0

0

0

0

0

0

0

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

.3

.1

' 0.07 

3.8

Mar.

0

0

0

0

0

0

0

0

0

0

0

97.8 

6,010

Apr.

0

0

0

0

0

0

0

0

0

0

0 

0
SANTA ANA RIV5R BASIN 217

Discharge, In second-feet, at indicated time, 1958

Sour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

March 1

9.5

6.5

1.4

.5

62

29

12

7

5

4.2

3.7

2.4

1.7

.9

.3

.3

.2

.2

.1

.1

.1

.1

.1

.1

March 2

0.1

.6

4.7

4.7

9

14

16

10

8.5

10

16

12

1,200

2,250

March 3

280

216

158

172

192

170

118

88

72

March 4

47

36

34

49

41

Cajon Creek near Keenbrook, Calif.

Location.- Two water-stage recorders, lat. 34°16'50n , long. 117°27'50n , near north 

boundary of aec. 13, T. 2 N., R. 6V., 300 feet and 1,800 feet above mouth of Lone 

Pine Creek, and about 1 mile north, of Keenbrook. Altitude, about 2,620 feet.

Drainage yga.- Area, 40.9 equare miles. Average altitude, 3,960 feet. Maximum altltude, 6,917 feet. Average slope, 47 percent. Length of main stream channel, 13 

mllea. Average alope of main stream channel, 6.1 percent.

Page-height record.- Water-stage recorder graph at lower station except 10 a.m. Mar. 2 

to Mar. 11; at upper station except 2 p.m. Mar. 2 to Mar. 17.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 600 eeoond-feet; peak discharge determined by slope-area measurement. Discharge for the maximum 24 hours determined largely from a rainfall-runoff relation, 

using the Del Roaa and Devil Canyon recording rain gage records aa a basla for 

distribution of the storm rainfall. Discharge Mar. 2-15 baaed on rainfall-runoff 

studies, partial gage-height record, discharge meaaurementa and comparison with 

nearby streams.

Maxima.- 1938; Discharge, 14,600 second-feet about 5 p.m. Mar. 2. 

1919-37: Discharge, about 5,000 second-feet Dec. 20, 1921.

Remarks.- Reoorda good except those for Mar. 2-15, which are poor. No diversion or 

regulation above gage.

Mean dally discharge, In aeoond-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

52

11

83

112

29

22

18

16

73

41

Mar.

580

3,800

2,050

535

231

160

130

110

90

80

Apr.

26

24

26

24

22

21

21

21

21

21

Day

11

12

13

14

16

16

17

18

19

20

Feb.

322

77

34

25

21

18

17

19

23

17

Mar.

76

150

80

75

64

56

48

40

43

44

Apr.

22

22

20

19

17

14

13

12

12

12

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

14

13

12

11

11

10

76

533

61.0

3,390

Mar.

42

34

33

30

28

26

31

29

28

27

29

17,410

Apr.

11

11

11

11

14

12

11

11

13

12

16.9

1,010
218 FLOODS OF MARCH 1938 M SOtJTHBRH CALIFOHHIA

Gage height, In feet, and discharge, In second-feet, at Indicated time, 1938

»

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

1.70

2.50

3.00

11

46

140

t

Feet Sec. ft.

February 28

2.91

3.51

3.38

3.73

3.58

3.51

3.53

3.67

4.25

5.14

4.58

4.15

3.74

3.60

3.56

3.69

3.45

3.37

3.37

3.37

3.36

4.55

5.61

6.O9

119

345

280

460

385

350

360

435

730

1,320

900

680

482

415

400

465

345

305

305

305

300

895

1,510

1,790

Feet jSee.ft.

March 1

2,100

2,700

1,150

700

600

520

470

435

410

380

355

335

320

300

280

270

260

250

235

225

215

210

205

200

Feet Sec.ft.

March 2

200

200

205

210

230

380

1,500

2,000

2,400

2,500

2,500

2,250

2,700

3,300

Feet Sec.ft.

March 3

Feet Sec.ft.

March 4

Lone Pine Creek near Keenbrook, Calif.

Location.- Water-stage recorder, lat. 34°15'55", long. 117°27'55", In S«t aec. 12, T. 2 

K., R. .6 W., 50 feet upstream from Atehison, Topeka * Santa Fe Railway bridge, and 1 

mile north of Keenbrook. Altitude, about 2,630 feet.

Drainage area.- Area, 15.3 square miles. Average altitude, 4,700 feet. Maximum altitude, 8,500 feet. Average slope, 48 percent. Length of main stream channel, 10.2 

miles. Average slope of main stream channel, 11 percent.

Page-height record.- Record lost due to destruction of gage shelter and well.

Discharge record.- Maximum discharge obtained by slope-area measurement. Discharge for 

the maTlimim 24 hours determined from rainfall-runoff study; the average rainfall on 

the area was distributed on the basis of records from the Del Rosa and Devil Canyon 

recording rain gagea. Remainder of record determined from current-meter measurements 

and by comparison with record for Cajon Creek near Keenbrook.

Maxima.- 1938: 

1919-37:

Discharge, 6,180 second-feet Mar. 2.

Discharge, 810 second-feet (estimated) Dec. 19, 1921.

Remarks.- Records poor. Ho diversion or regulation above station.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

18

.7

10

9.5

1.3

1.1

.9

.8

12

8

Mar.

206

1,480

840

190

90

46

28

18

13

9

Apr.

5.5

5.5

5.5

6

5.5

5.5

5.5

5

5

5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

60

12

3.9

1.8

.9

.1.0

1.2

1.4

1.7

1.4

Mar.

7

34

8

5

4.7

4.5

4.2

3.9

3.8

3.7

Apr.

5

5

5

5

4.9

4.8

4.8

4.8

4.7

4.7

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

1.2

1.1

.9

.9

.8

.7

4.0

67

8.01

445

Mar.

3.5

3.4

3.4

3.3

3.2

3.2

3.4

3.7

4.2

4.7

5.5

98.1

6,030

Apr.

4.7

4.7

4.8

5

5

5

5

5

5

5.5

302
SANTA ANA RIVER BASIN 219

Day Creek near Etiwanda, Calif.

Location.- Water-stage recorder and broad-crested weir, lat. 34°11'00", long. 117°32' 

25 , in SWfc sec. 8, T. 1 N., R. 6 V., a quarter of a mile downstream from confluence 

of two main forks, and 6 miles north of Etiwanda. Altitude, about 2,940 feet.

Drainage area.- Area, 4.8 square miles. Average altitude, 5,208 feet. Maximum altltilde, 8,911 feet. Average slope, 52 percent. Length of main stream channel, 4.0 

miles. Slope of main stream channel, 28 percent.

Page-height record.- Record lost due to destruction of recording gage.

Discharge record.- Maximum discharge and discharge fcr the maximum 84-hour period obtained by rainfall-runoff studies, using records from Camp Baldy and Etiwanda recording rain gages aa basis for distributing the rainfall. Records liar. 4-11 obtained by use of retention curves; other records computed from eurrent-meter measurements and by comparison with nearby stations.

Maxima.- 1938: Diecharge, 4,200 second-feet Mar. 2.

1929-37: Discharge, 192 second-feet Feb. 11, 1936.

Remarks.- Records poor. No regulation or diversion above gage during flood period. 

Mean dally discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

11

7

50

49

29

19

13

11

16

19

Mar.

108

1,055

449

121

80

60

55

52

50

50

Apr.

31

31

30

29

28

27

27

26

25

24

Day

11

12

13

14

15

16

17

18

19

SO

Feb.

31

33

25

20

19

19

17

17

17

17

Mar.

50

130

180

78

63

55

50 

46

43

42

Apr.

23

22

23

24

23

18

17/

18

23

26

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

17

14

13

12

12

12

14

107

OO Q

1,270

Mar.

40

39

38

37

36

36

34

33

33

32

52

103

6,360

Apr.

25

25

83

23

20

20

20

20

20

22

1,410

Cuoamonga Creek near Upland, Calif.

Location.- Water-stage recorder and concrete control, lat. 34°10'15", long. 117°37'55", 

In HEi see. 17, T. 1 N., R. 7 W., 6 miles north of Upland. Altitude, about 2,550 

feet.

Drainage area.- Area, 10.1 square miles. Average altitude, 5,275 feet. Maximum altitude, 8,911 feet. Average slope, 54 percent. Length of main stream channel, 5 

miles. Average slope of main stream channel, 24 percent.

Gage-height record.- Water-stage recorder graph except Mar. 2 to Apr. 15.

Pis charge record.- Stage-discharge relation well defined below 100 eeoond-feet prior to 

March 2~Concrete control destroyed and station buried in debris on March 2. Maximum discharge estimated by consideration of slope-area studies, rainfall-runoff 

studies, and knowledge of local conditions. Discharge for the maximum 24 hours determined from rainfall-runoff study, using the records from Camp Baldy and Etiwanda 

recording rain gages as a basis for distributing the storm rainfall. Discharge Mar. 

4-11 obtained by use of retention curves.

Maxima.- 1938: Discharge, 10,300 second-feet about 3 p.m. liar. 2. 

1928-37: Discharge, 475 second-feet Feb. 11, 1936.

Remarks.- Records fair. No regulation or diversions above gage during flood period. 

Mean dally discharge, in second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

14

7

60

53

32

21

14

12

22

24

Mar.

223

2,120

719

266

149

122

109

81

68

68

Apr.

36

35

34

33

32

31

30

30

29

28

Day

11

12

13

14

15

16

17

18

19

20

Mean monthly discharge, in second

Feb.

43

46

33

25

20

20

18

17

18

16

Mar.

68

167

242

108

80

69

66

63

60

58

Apr.

28

27

28

29

30

23

19

20

29

29

Day

21

22

23

24

S5

26

S7

28

29

30

31

Feb.

14

13

12

12

11

11

16

222

29.5 

1,640

Mar.

55

53

51

49

47

45

43

42

40

39

37

174 

10,720

Apr.

29

26

24

25

21

21

21

21

22

22

27.1 

1,610
220 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Oage height, In feet, and discharge, In seoond-feet, at Indicated time, 1938

Hour

1

23 '

4

6

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

11

Feet

Febru

1.76

1.78

1.80

1.79

1.78

1.78

1.79

1.82

1.88

1.93

1.93

1.92

1.92

1.98

2.01

2.02

2.02

2.02

2.02

2.06

2.20

2.21

2.20

2.18

Sec.ft.

ary 27

11

12

12

12

12

12

12

13

14

16

16

16

16

17

18

18

18

18

18

19

23

23

23

22

Feet Seo.ft.

February 28

2.32

3.01

3.21

3.46

3.64

3.67

3.66

3.86

.00

.10

.02

.43

.26

.20

.00

.28

.95

.03

.07

.06

.31

.68

6.15

5.16

37

49

67

96

123

129

127

167

198

226

203

329

270

266

198

279

186

206

217

214

288

431

680

680

Feet | Seo.ft.

March 1

4.87

4.60

4.65

4.46

4.46

4.36

4.30

4.16

3.73

3.66

3.68

3.90

4.08

3.65

3.65

3.75

3.76

3.80-

. 3.78

3.78

3.69

3.65

3.64

3.72

520

366

418

336

336

302

286

240

140

126

130

176

220

126

126

144

144

154

160

150

132

126

123

138

San Jaolnto River near San Jaolnto, Oallf.

lat. 33°44'06n , long. 116°49'46n , In SBfc Bee. 13, T. 6 3., R 

, at highway bridge, Si miles southeast of San Jaolnto. Altitude, about 1,980 

feet.

Drainage area.- Area, 140 square miles. Average altitude, 6,250 feet. Maximum altltude, 10,800 feet. Average alope, 41 peroent. Length of main stream channel, 21 

miles. Average alope of main stream channel, 8.7 peroent.

Page-height reoord.- Staff gage read dally] .more frequently during flood period.

Discharge record.- Stage-discharge relation fairly veil defined by current-meter 

measurements below 200 second-feet; peak discharge la mean of a lope-area and contracted opening determinations. Discharge Feb. 28 to Mar. 4 baaed on gage-heights, 

current-meter measurements, and estimates of discharge furnished by Metropolitan 

Water Dlatriot of Southern California.

Maxima..- 1938: 

920-371

Discharge, 14,300 second-feet about 12 p.m. Mar. 2. 

Discharge, 46,000 second-feet (estimated) Feb. 16, 1927.

Remarks.- Records poor. Some regulation during flood at Lake Hemet; no diversions. 

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.6

16

4.6

46

35

28

17

13

13

37

Mar.

890

3,170

5,100

1,600

780

622

407

368

343

296

Apr.

134

128

128

128 

112

115

126

103

99

99

Day

11

12

13

14

15

16

17

18

19

2CH

Feb.

29

74

46

30

24

24

18

13

23

21

Mar.

366

2,070

1,280

940

666

550

494

444

374

368

Apr.

99

99

99

111

98

100

98

84

88

88

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

17

16

16

16

18

16

22

316

33.6

1,880

Mar.

366

356

174

162

163

153

170

167

167

146

140

748

46,670

Apr.

88

86

79

76

84

168

138

110

94

108

108

6,260
SANTA ANA RIVER BASIN 221.

San Jaclnto River at Railroad Canyon Reservoir, near Elslnore, Calif.

Location.- Water-stage recorder, lat. 530 41'40n , long. 1170 16'20", In

T. 6 S., R. 4 W., 3 miles east of Elslnore. Altitude, about 1,330 feet

Drainage area.- 709 square miles. 

Sage-he ipht record.- Water-stage recorder graph.

Inflow record.- Obtained from stage-capacity curve and operation records. 

Maximum.- 1938: Inflow, 3,150 second-feet about 8 p.m. liar. 2. 

Remarks . - Records furnished by Corps of Engineers, U. S. Army. 

Mean daily inflow, in second-feet, 1938

sec. 2,

Feb. 27

28

Mar. 1

2

Runoff,

.... 150

.... 150

.... 150

.... 1,340

in acre -feet

Mar. 3

4

5

.... 971

.... 1,820

.... 2,190

.. 13,430

Inflow, In second-feet, at Indicated time, 1938

Hour

1

2

3

4

 5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

March 2

150

200

230

260

300

400

475

575

725

900

1,100

1,160

1,350

1,500

1,650

1,900

2,150

2,500

2,900

3,150

2,980

2,400

2,100

1,900

March 3

1,800

1,650

1,500

1,400

1,300

1,200

1,130

1,100

1,000

900

800

750

700

660

650

630

620

625

640

670

700

740

780

800

March 4

900

1,000

1,050

1,140

1,250

1,350

1,430

1,530

1,620

1,690

1,760

1,850

1,920

2,000

2,100

2,170

2,250

2,300

2,400

2,450

2,500

2,580

2,630

2,650

March 5

2,600

2,500

2,370

2,250

2,150

2,100

2,100

2,050

2,030

2,000

1,900

1,880

March 6

1,850

1,750

1,700

1,620

1,620

San Jacinto River near Elslnore, Calif.

Location.- Water-stage recorder, lat. 33°39'45", long. 117°17'45", near east line of 

sec. 9, T. 6 S., R. 4 W., 2 mllee east of Elsinore, and 2& miles upstream from 

Elslnore Lake (low-water stage). Altitude, about 1,270 feet.

Drainage area.- Area, 717 square miles. Average altitude, 2,710 feet. Maximum altltude, 10,805 feet. Average slope, 34 percent. Length of main stream channel, 61.5 

miles. Average slope of main stream channel, 1.6 percent.

Page-height record.- Wt -r-atage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

1,790 second-feet; extended logarithmically to peak stage. Record verified by comparison with outflow from Railroad Canyon Reservoir lj miles upstream.

Maxima.- 1938: Discharge, 2,790 second-feet 2 to 4 a.m. Mar. 5 (gage height, 8.41 feet).

1916-37: Discharge, about 16,000 second-feet Feb. 17, 1927 (gage height, 11.8 

feet).

Remarks.- Records good. Storage at Railroad Canyon Reservoir and Lake Hemet; several 

divers ions for irrigation. Seepage from Metropolitan Water District's San Jaclnto 

tunnel was pumped into San Jacinto River above gage.
FLOODS OF MARCH 1938 IN SOOTHERS CALIFORNIA

Mean dally discharge, in second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

52

48

47

55

51

46

46

46

53

54

Mar. .

180

961

1,400

1,570

2,470

1,500

964

604

594

536

Apr.

126

115

103

88

79

81

78

78

74

59

Day

11

12

13

14

15

16

17

18

19

20

Feb.

59

66

59

56

54

52

51

52

58

53

Mar.

476

468

399

436

675

765

684

576

496

420

Apr.

49

47

45

53

68

75

,70

65

58

50

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

50

51

53

56

53

52

86

100 -

3,090

Mar.

371

324

288

252

220

194

169

149

143

141

136

599

36,820

Apr.

49

49

45

41

42

48

81

105

99

86

70.2

4,180

Gage height, in feet, and discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

Q

10

11

K

1

2

3

4

5

6

7

8

9

10

11

H

Feet

Ma]

4.20

4.22

4.30

4.52

4.70

5.20

5.70

6.90

7.42

7.88

8.19

8.04

Sec.ft.

rch 2

169

174

192

246

297

472

689

1,410

1,820

2,230

2,550

2,390

Feet Sec.ft.

March 3

7.92

7.70

7.44

7.18

6.92

6.71

6.50

6.29

6.14

6.02

5.92

5.84

2,270

2,070

1,840

1,630

1,430

1,270

1,140

1,020

930

860

806

760

Feet Sec.ft.

March 4

5.78

5.73

5.72

5.78

5.96

6.50

7.25

7.52

7.79

8.03

8.20

8.32

8.38

730

706

702

730

830

1,130

1,690

1,920

2,160

2,390

2,570

2,700

~

2,760

Feet

Ma]

8.41

8.41

8.37

8.33

8.26

8.19

8.11

8.03

7.93

7.84

7.75

7.66

Sec.ft.

'Oh 5

2,790

2,790

2,750

2,710

2,610

2,540

2,430

2,330

2,220

2,120

2,020

1,920

Elsinore Lake at Elsinore, Calif.

Location.- Staff gage, lat. 33°40'35", long. 117°21'30", in La Laguna grant, on northeast snore at Aloha Beach Club, Elsinore, Riverside County. Zero of gage is 1,200 

feet above mean sea level.

Sage-height record.- Staff-gage readings about once daily during flood periods.

Remarks.- Elsinore Lake overflows only during and after years of heavy rainfall. 

Temescal Creek is the high water outlet of lake. There was flow in creek during 

most of 1916 and the first half of 1917. A history of the lake is given in WaterSupply Papers 426, 429, and 441. Fart of record furnished by D. R. Crane, Elsincre, 

Calif.

Sage height, in feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

50.0

50.0

Mar.

51.0

51.1

52.4

52.9

53.7

54.5

55.0

55.4

55.6

55.8

Apr.

58.5

58.5

58.6

58.6

58.6

58. 6

58.6

58.6

58.6

58.7

Day

11

12

13

14

15

16

17

18

19

20

Feb.

50.3

50.4

Mar.

56.0

56.3

56.4

56.6

56.7

57.0

57.2

57.4

57.6

57.7

Apr.

58.7

58.7

58.7

58.7

58.7

58.7

58.7

58.7

58.8

58.7

Day

21

22

23

24

25

26

27

28

29

30

31

Feb. '

50.5

50.6

Mar.

57.8

57.9

58.0

58.1

58.2

«8.3

58.3

58.3

58.4

58.4

58.4

Apr.

58.8

58.8

58.8

58.8

58.8

58.8

58.8

58.8

58.8

58.9
SANTA AHA RIVER BASIN

Elainore Lake, capacity table*

Gage -height 

Tfeet)

45 

46 

47 

48 

49

Acre -feet

60,000 

64,500 

68,500 

73,000 

77,500

Gage -height 

Tfeet)

50 

51 

52 

53 

54

Acre -feet

82,000 

86,500 

92,000 

97,500 

102,500

Qage -height 

Tfeet)

55 

56 

57 

58 59'

Acre-feet

107,500 

112,500 

118,000 

124,000 

130,000

* From unpublished report by P. H. Albright, Elainore Valley Water Supply

Temescal Creek near Corona, Calif.

Location.- Water-atage recorder, lat. 33°50'30", long. 117°30'45", In El Sobrante de 

San Jaclnto grant, half a mile upstream from Blue Diamond Quarry, and 4 miles southeast of Oorona, Riverside County. Altitude, 730 feet.

Drainage area below Elsinore Lake.- Area, 157 square miles (924 square miles Including 

San Jaclnto River;.Average altitude, 1,451 feet. Maximum altitude, 5,680 feet. 

Average slope, 33 percent. Length of main stream channel, 22 miles. Slope of main 

stream channel, 4.1 percent.

Page-height record.- Water-stage recorder graph except Mar. 2-14.

Dlacharge record.- Stage-discharge relation poorly defined by current-meter measurementa 

below 100 second-feet; peak discharge determined by alope-area measurement. Discharge for maximum 24 hours determined from rainfall-runoff relation, using the 

Silverado and Riverside recording rain gage records aa a basis for distribution of 

the storm precipitation. Discharge Mar. 4-14 determined from one current-meter 

measurement and by comparison with nearby stations.

Maxima.- 1929-37: 1938: Discharge, 14,900 aecond-feet 7 p.m. Mar. 2. 

Discharge, 2,350 aecond-feet Feb. 6, 1937.

Remarks.- Recorda poor. Drainage area above Elsinore Lake did not contribute any runoff 

*during flood. Lee Lake dam failed In the late afternoon of Mar. 2.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7-

8

9

10

Feb.

4.0

9

7

7.5

6

5.5

6

7

7.5

8

Mar.

88

3,460

2,520

432

194

136

112

106

102

100

Apr.

100

88

82

84

91 .

87

72

68

65

64

Day

11

12

13

14

15

16

17

18

19

20

Feb.

8

8

6

7

7

6

5

5

5.5

4.4

Mar.

216

152

125

120

116

112

107

123

100

87

Apr.

64

55

50

46

46

46

47

48

46

49

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

4.4

4.4

4.0

4.0

4.0

4.8

10

11

6.29

349

Mar.

75

96

108

104

100

118

115

129

130

122

102

19,250

Apr.

46

46

42

42

39

33

24

22

28

25

54.8

3,260

Chlno Creek near Prado, Calif.

Location.- Water-stage recorder, lat. 33°53'40", long. 117°38'4011 , In El Rlncon grant, 

at Chlno-Rlncon road, 1 mile weat of Prado, Riveraide County. Altitude, 460 feet.

Drainage area.- About 176 square miles.

Sage-height record.- Water-stage recorder graph except 1 p.m. Mar. 2 to Mar. 21.

Discharge record.- Stage-discharge relation defined by currant-meter measurementa below 

300 aecond-feet; extended logarithmically to peak discharge determined by alope-area 

measurement of the main channel (5,000 sec.-ft.) plua estimated discharge of secondary channels. Discharge Mar. 2 to Apr. 30 computed by interpolating between discharge measurementa and by comparison with adjacent streams.

Maxima.- 1938: 1929-37: Discharge, 5,200 second-feet about 6 p.m. Mar. 

Discharge, 1,440 second-feet Jan. 1, 1934.

2.

Remarks.- Records fair. No diversion or regulation during flood.
224 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Mean daily discharge, In second-feet, 1938

Day

1

S

3

4

5

6

7

8

9

10

Feb.

78

32

21

50

21

13

11

9.5

47

67

Mar.

302

1,580

1,200

371

205

155

140

132

130

128

Apr.

13

11

9

8.5

8.5

9

8

6.5

6

6

Day

11

12

13

14

15

16

17

18

19

20

Feb.

47

96

29

20

19

17

15

14

19

16

Mar.

130

190

250

190

140

100

90

86

76

66

Apr.

6.5

7

7.5

8

8

8.5

8.5

8

8

8.5

Day

21

22

23

24

25

28

27

28

29

30

31

Feb.

15

14

14

14

14

13

42

89

1,700

Mar.

60

50

44

88

35

32

28

24

21

. 18

15

196

12,050

Apr.

9.5

11

13

14

15

14

12

10

9

10

558

Gage height, in feet, and discharge, in second-feet, at indicated time, 1938

W

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec.ft.

February 27

2.14

2.27

2.45

2.55

2.65

2.77

2.95

3.50

4.23

4.77

4.85

4.70

4.40

4.13

13

15

20

22

25

29

35

36

93

126

131

121

103

87

Feet | Sec. ft.

February 28

3.93

3.75

3.56

3.45

3.35

3.25

3.55

4.20

4.65

4.75

4.85

5.07

5.18

5.20

5.10

4.90

4.70

4.50

76

68

59

54

50

46

59

92

119

125

132

147 _

154

156

149

135

122

110

Feet Sec.ft.

March 1

4.60

4.70

5.00

6.20

7.30

7.90

8.40

8.62

8.50

8.25

7.90

7.60

7.40

7.30

7.20

7.00

6.77

6.51

6.30

6.15

6.05

5.90

5.75

5.60

116

122

142

237

345

411,

476

503

491

456

411

379

357

346

335

314

291

265

247

233

224

212

200

188

Feet Sec.ft.

March 2

5.48

5.35

5.25

5.15

5.25

5.75

6.20

7.30

8.20

9.30

10.85

11.00

10.90

178

168

160

153

160

199

238

346

452

593

835

858

900

1,000

1,200

2,200

3,500

5,200

4,400

4,000

3,600

3,200

2,900

2,700

Feet Sec.ft.

March 3

2,200

1,850

1,600

1,300

1,150

1,000

900

810

730

660

600

550

Feet Sec.ft.

March 4

510

480

440

410

380

350

330

310

290

280

265

255

San Antonio Creek near Claremont, Calif.

Location.- Water-stage recorder and concrete control, lat. 34°12'501', long. 117°40'0011 , 

in HWtSE-£ sec. 36, T. 2 N., R. 8 W., at highway bridge, half a mile above Southern 

California Edison Co.'s Sierra power plant, and 8 miles northeast of Claremont. Altitude, about 3,400 feet.

Drainage area.- Area, 16.9 square miles. Average altitude, 6,580 feet. Maximum altituae, 10,080 feet. Average slope, 49 percent. Length of main stream channel, 5.75 

miles. Average slope of main stream channel, 21 percent.

Gage-height record.- Water-stage recorder graph except 10 a.m. Mar. 2 to Mar. 29.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

125 second-feet; extended logarithmically to 900 second-feet. Concrete control was 

destroyed on Mar. 2. The stream changed its channel above gage, so that only a small 

part of the flood runoff passed the gage. Maximum discharge estimated by consideration of slope-area studies, rainfall-runoff studies, and knowledge of local conditions,. 

Discharge for the maximum 24 hours determined from rainfall-runoff study using Camp 

Baldy recording rain gage record as a basis for distribution of total storm precipitation ; for remainder of the period of missing record determined from measurements 

made by the Los Angeles County Flood Control District at the mouth of the canyon,from 

retention studies, and by a comparison with other streams.

Maxima.- 1938: 1917-37: Discharge, 21,400 second-feet about 4 p.m. Mar. 2. 

Discharge, 1,020 second-feet Dec. 19, 1921.

Remarks.- Records good except for Mar. 2-29, which are poor. Discharge is for natural 

flow of the stream and includes flow in Southern California Edison Co. 's canal; no 

flow in canal Mar. 2 to Apr. 30.
SANTA ANA RIVBR BASIN 226

Mean daily discharge, In second-feet, 1938

Day

1

2

3

4

6

6

7

8

9

10

Feb.

19

16

26

SO

27

23

22

20

28

26

Mar.

227

4,110

964

436

364

272

227

227

136

136

Apr.

126

125

130

140

140

140

150

150

150

140

Day

11

12

13

14

15

16

17

18

19

20

Feb.

52

35

25

24

26

26

25

24

26

25

Mar.

136

274

375

202

175

168

163

158

154

153

Apr.

140

130

130

125

120

115

110

105

102

98

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

25

24

24

24

24

24

26

119

OQ 1

1,620

Mar.

161

161

160

160

148

143

140

138

135

133

130

TAO

21,060

Apr.

94

98

90

97

86

82

80

78

76

75

113

6,760

Discharge, In second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

6

7

8

9

10

11

H

February 28

31

36

41

47

49

53

56

64

70

83

83

86

96

109

109

128

123

119

117

119

141

196

435

921

March 1

771

581

451

356

301

266

231

211

191

176

166

153

130

112

108

104

100

98

96

95

94

93

93

93

March 2

94

95

98

108

110

120

140

180

350

740

Santiago Creek near Villa Park, Calif.

Location.- Water-stage recorder, lat. 33* 49" 10", long. 117e 46'30B , in S»t sec. 13, T. 

4 S., R. 9 W., five-eighths of a mile below diversion dam of Serrano and Carpenter 

Irrigation Districts, and 1-3/4 miles northeast of Villa Park. Altitude, about 

420 feet.

Drainage area.- Area, 83.8 square ailes. Average altitude, 1,934 feet. Maximum altltude, 5,680 fest. Average slope, 43 percent. Length of main stream channel, 16.5 

miles. Slope of main stream channel, 6.0 percent.

Sage-height record.- Water-stage recorder graph except Fob. 

21-307

1-14, Mar. 4-6, and Apr.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 1,200 second-feet; extended above on basis of a slope-area measurement of the 

peak. Discharge for period of missing gage-height record bassd on discharge 

measurements and comparison with Santiago Oreek at Santa Ana.

Maxima.- 1938: Discharge, 5,200 second-feet 7 p.m. Mar. 2 (gage height, 6.87 feet). 

1920-37: Discharge, 11,000 second-feet Feb. 16, 1927 Tgage height, 8.4 feet), 

by slope-area method.

Remarks.- Records fair. Flow partly regulated by storage in Santiago Reservoir. 

Irvlne Company and Serrano and Oarp«nfcer Irrigation Districts divert above gage.
226 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

14

5

3.0

2.0

1.5

1.2

1.0

.9

.8

.7

Mar.

176

2,660

3,190

1,190

420

275

264

253

219

197

Apr.

68

68

62

62

62

54

44

32

36

54

Day

11

12

13

14

15

16

17

18

19

20

Feb.

0.7

.8

.8

.8

.8

.8

.6

.7

.9

.8

Mar.

186

583

1,030

646

442

322

281

253

214

197

Apr.

65

68

65

62

65

46

27

17

17

17

Day

21

22

23

24

25

26

27

28

29

30

31

Runoff, in acre-feet .......................................

Feb.

0.7

.6

.6

.5

.3

.3

1.4

13

1.97

109

Mar.

180

160

150

117

101

70

82

79

73

70

70

456

28,070

Apr.

10

9

8

6

15

12

10

8

8

7

 tgt i

2,150

Sage height, in feet, and discharge, in second-feet, at indicated time, 1958

w

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

0.52

.52

.52

.52

.52

.52

.52

.53

.56

.59

.62

.63

.64

.66

.66

.67

.68

.70

.72

.73

.75

.77

.89

.85

0.3

.3

.3

.3

.3

.3

.3

.4

.5

.7

.9

1

1.1

1.1

1.3

1.5

1.6

1.9

2.2

2.3

2.6

3.1

6.5

4.9

Feet Sec. ft.

February 28

0.83

.80

.80

.82

.91

.94

1.06

1.01

.96

.90

.89

.87

.85

.83

.82

.80

.79

.78

..77

.76

.77

.93

1.2S

1.94

4.4

3.7

3.7

4.2

7

8

15

12

9

6.5

6.5

5.5

4.9

4.4

4.2

3.7

3.5

3.3

3.1

2.8

3.1

10

41

281

Feet Sec. ft.

March 1

2.70

3.03

3.05

2.35

1.96

1.77

1.54

1.40

1.25

1.12

1.04

.97

.93

.88

.85

.81

.77 ".74

.70

.68

.68

.67

.68

.74

590

722

730

447

309

241

158

117

82

59

51

43

41

38

38

39

40

43

44

49

58

56

58

69

Feet Sec. ft.

March 2

0.85

.90

.94

1.30

2.00

2.57

2.77

2.79

2.95

3.40

3.93

3.84

4.03

4.35

4.80

4.90

4.90

5.73

6.27

6.22

6.27

6.20

6.18

5.93

96

109

139

287

750

1,230

1,410

1,430

1,590

2,050

2,650

2,570

2,750

3,080

3,580

3,690

3,690

4,600

5,200

5,120

5,200

5,100

5,080

4.820

Feet Sec. ft.

March 3

5.63

5.47

5.33

5.15

5.04

4.95

.87

.84

.77

.67

.56

.47

.37

.26

.09

.00

3.91

3.82

3.71

3.60

3.54

3.47

3.40

3.35

4,480

4,290

4,130

3,950

3,840

3,740

3,660

3,620

3,550

3,440

3,320

3,220

3,110

2,990

2,810

2,720

2,630

2,540

2,410

2,280

2,210

2,130

2,050

2.000

Feet | Sec. ft.

March 4

1,640

1,350

1,120

930

770

660

Santiago Creek at Santa Ana, Calif.

Location.- Water-stage recorder, lat. 33°46'00", long. 117°52'45", in Santiago de Santa 

Ana grant, at end of Baker Street, Santa Ana, Orange County. Altitude, about 120 

feet.

Page-height record.- Water-stage recorder graph except for low stages when water was below intake, and* Mar. 5-6, when intake was clogged by silt.

Discharge record.- Stage-discharge relation fairly well defined below 1,000 second-feet 

by current-water measurements; extended to peak etage on basie of mean depth-wean 

velocity relation. Shifting control corrections' used throughout. Discharge for 

periods of miss fag gage-height record based on discharge measurements and comparison 

with Santa Ana River at Santa Ana.

 1929-37i Maxima.- 1938: Discharge, 4,400 second-feet 8:30 p.m. Mar. 2 (gage height, 7.40 feet). 

Discharge, 3,270 second-feet Feb. 6, 1937 (gage height, 6.90 feet).

Remarks.- Records fair. Regulation at Santiago Reservoir.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

32

0

0

0

0

0

0

0

68

2.5

Mar.

340

1,990

2,320

1,060

650

300

151

149

116

69

Apr.

17

17

17

21

25

29

28

25

29

62

Day

11

12

15

14

15

16

17

18

19

20

Feb.

53

15

.5

.1

0

0

0

10

37

30

Mar.

54

254

660

500

333

208

166

136

111

91

Apr.

64

68

68

68

71

67

35

12

1.0

.5

Day

21

22

23

24

25

26

27

28

29

30

31

Runoff, in acre-feet. . .......................................

Feb.

10

1.0

.5

0

10

5

40

80

783

Mar.

74

71

67

61

55

47

43

39

34

28

25

20,220

Apr.

0

0

0

0

7

0

0

0

0

4.2

1,460
SANTA ANA RIVER BASIN 227

Gage height, in feet, and discharge, in second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

it

Feet Sec.ft.

March 1

2.70

4.30

3.00

2.65

2.40

2.00

710

1,460

830

690

600

465

380

300

240

190

180

170

>. 150

Feet | Sec.ft.

March 2

3.10

3.50

3.55

3.30

3.25

4.00

4.20

4.70

5.00

6.20

6.40

5.90

5.60

6.00

7.25

7.30

7.00

7.05

7.00

180

210

250

350

500

1,050

1,250

1,280

1,150

1,120

1,510

1,630

1,930

2,130

3,010

3,180

2,780

2,620

3,010

4,300

4,300

4,000

4,050

4,000

Pest | Sec.ft.

March 3

6.95

6.85

6.50

6.20

5.95

5.70

5.55

5.40

5.24

5.10

4.9

4.75

4.60

4.40

4.20

4.05

3.90

3.77

3.66

3.57

3.50

3.40

3.33

3.25

3,950

3,850

3,520

3,270

3,050

2,890

2,740

2,620

2,500

2,410

2,270

2,170

2,070

1,940

1,820

1,700

1,640

1,560

1,500

1,450

1,410

1,360

1,320

1,280

Feet Ssc.ft.

March 4

3.20

3.15

3.12

3.07

3.05

3.00

2.95

2.90

2.87

2.85

2.80

2.77

2.74

2.70

2.66

2.63

> 2.50

1,260

1,230

1,220

1,190

1,180

1,160

1,140

1,120

1,100

1,090

1,060

1,060

1,040

1,020

1,000

990

> 930

1 __ ________ , _________ Y.UU' ?t,UUU O.gO J.,SgU ________ ____

Supplemental record,- Mar. 2, 8:30 p.m., 7.40 ft., 4,400 sec. -ft.

Irvine Ranch drainage canal near Tustin, Calif.

", in San Joaquin grant 

Altitude, about 26

Location. - Water-stage recorder, lat. 330 40'30", long. llVSO'O 

at Lane Road Bridge, 5 miles south cf Tustin, Orange County. 

feet.

Drainage area.- 93 square miles.

Gage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge rslation fairly well defined below 2,200 second-feet 

by current-meter measurements, extended to peak on basis of slope-area:determlnatlons.

i

- 1938: Discharge, 5,710 second-feet Mar. 2 (gage height, 18.2 feet). 

930-37: Discharge, 5,020 second-feet Feb. 6, 1937.

Remarks . - Canal carries storm runoff from foothills, crosses ranch, and drains a small 

area between Tustin and the ocean. Reccrds furnished by Orange County Flood Control 

District, through M. N. Thompson, chief engineer.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

10

.1

0

7

0

0

0

0

15

2.2

Mar.

373

3,200

1,040

12

10

7

5

4.0

3.0

2.0

Apr.

0.5

.4

.4

.4

.3

.3

.3

.3

.3

.3

Day

11

12

13

14

15

16

17

18

19

20

Feb.

12

5

.3

.3

.2

.2

.2

.2

.1

.1

Mar.

1.0

146

98

6

5

4.0

3.0

2.0

1.0

1.0

Apr.

0.3

.3

.3

.3

.3

.3

.2

.2

.2

.2

Day

21

22

23

24

25

26

27

28

29

30

31

Runoff, In acre-feet .........................................

Feb.

0.1

0

0

0

0

0

1.8

30

154

Mar.

1.0

1.0

1.0

1.0

1.0

.9

.8

.7

.6

.5

.5

159

9,780

Apr.

0.2

.2

.2

.2

.2

.2

.2

.2.

.2

.2

0.27

16
888 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Page.height, In feet, and dle-oh*rge, in eecond-feet, at Indicated time, 1988

i

i

2

3

4

6

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

e

1011

vf

Feet] See. ft.

February 27

3.0

3.05

3.10

3.87

3.40

3.30

3.25

S^IQ

Feet Seo.ft.

February 28

4.10

4.35

5.00

4.45

4.25

4.10

3.90

3.78

3.75

3.60

3.60

3.55

3.45

.7.00

>

1> 7.0

1

25

33

61

39

33

89

23

20

20

17

17

> 15

934

Feet ( Sec. ft.

March 1

10.00

11.70

12.70

11.95

10.10

8.30

7.00

6.20

5.60

5.00

4.60

4.25

4.00

3.75

3.60

3.40

 3.00

1,010

1,600

2,040

1,700

1,050

590

340

210

130

71

49

37

29

22

17

> 12

Feet Seo.ft.

March 2

3.36

5.25

6.95

7.50

9.20

11.70

12.86

13.30

13.80

14.66

15.60

15.30

15.10

15.45

16.75

17.40

17.60

17.90

18.10

18.20

18.10

14

93

530

430

800

1,610

2,120

2,340

2,620

3,120

3,720

3,620

3,390

3,620

4,54,0

5,030

5,200

5,450

5,620

5,710

5,620.

6,450

5,110

4.660

Feet Seo.ft.

March 3

3,980

3,310

2,670

2,040

1,420

1,120

1,030

1,510

1,570

960

590

420

' 300

200

240

92

68

56

47

39

35

31

27

26

Feet 1 $eo.ft.

March 4

San Gabriel River BeeIn

Baat Fork of SKI Oabrlel River near Camp Bonlta, Calif.

 Location.- Water-Btage recorder, Zat. 34C 14'15 

V., R. 9 W., upatream from mouth of SUBanna 

Altitude, 1,500 feet.

34e l4 l 15*, long. 

Canyon,

117 0 49 I 10", in SHi aeo. 22, T. 8 

and 3 miles treat of Gamp Bonlta.

Drainage area.- Area, 91.4 square milea. Average altitude, 6,230 feet. Maximum altitude, 10,080 feet. Average alope, 54 percent. Length of main channel, 17.8 mllea. 

Average alope of main atream channel, 9.1 percent.

Qage-helght record.- Water-Btage recorder graph.

Discharge record.- Stage-dlaoharge relation defined by current-meter meaaurementa below 

21,300 aeoond-feet and extended to peak Btage on baaIs of mean depth-mean velocity 

relation.

Maxima.- 19361 Dlaoharge, 46,000 aeoond-feet Mar. 2 (gage height, 10.1 feet). 

1932-371 Dlecharge, 8,500 aeoond-feet Jan. 1, 1934.

Remarks.- Maximum discharge determined by the Geological Survey} other reoorda furniBhed by LOB Angelea County Flood Control District, through H. B. Hedger, Ohlef 

engineer.

Mean dally dlacharge, in aeoond-feet, 1938

Day

1

2

3

4

6

6

7

e

9

10

Feb.

79

60

188

299

186

184

110

108

123

186

Mar.

1,980

10,000

5,100

2,750

2,000

1,550

1,250

1,160

900

720

Apr.

350

345

340

340

350

340

330

320

3120

318

Day

11

12

13

H

15

16

17

IB

19

20

Mean monthly discharge, in second

Feb.

364

359

£72

1228

1«7

172

160

164

160

142

Mar.

620

2,100

1,860

1,400

1,1300

1,050

930

830

740

690

Apr.

310

305

295

290

280

270

205

265

1280

300

Day

21

22

23

24

25

26

27

28

29

30

31

-feet ...i...................

Feb.

137

137

127

132

137

132

182

1,270

212 

11,760

Mar.

640

600

570

540

5130

490

460

430

400

370

350

1,430 

87,630

Apr.

1395

286

280

268

271

264

836

238

838

238

894

17', 470
SAN GABRIEL RIVER BASIN 229

Discharge, In second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

M

February 27

130

^

132

134

137

142

163

168

174

180

198

236

242

264

264

February 28

284

396

850

1,180

,

1,430

1,310

2,120

1,550

1,520

1,670

1,650

1,940

1,760

1,850

2,400

3,480

March 1

4,400

4,630

4,340

3,150

2,040 __

1,510

2,000

2,510

2,180

1,260

1,270

1,300

1,400

1,380

1,650

San Sabriel River at Foothill Boulevard, near Azusa, Calif.

Location.- Water-stage recorder, lat. 34°08'1511 , long. 117°56'35", in Azuaa (Duarte) 

land grant, at highway bridge at Foothill Boulevard, 2 miles west of Azusa, Los 

Angeles County. Altitude, a bout 580 feet.

Drainage area.- Area, 230 square miles. Average altitude, 4,330 feet. Maximum altltude, 10,080 feet. Average slope, 43 percent. Length of main stream channel, 30 

miles. Average slope of main stream channel, 5.9 percent.

Sage-height record.- Water-stage recorder graph prior to 1:30 a.m. Mar. 3.

Dlacharge record.- Stage-discharge relation defined by current-meter measurements below 35,500 second-feetj extended to maximum discharge determined by slope-area 

method.

Maxima.- feet). 1938: Discharge, 61,800 second-feet 7:35 p.m. Mar. 2 (gage-height, 20.5 

1932-37: Discharge, 10,000 second-feet Jan. 19, 1933.

Remarks.- Records fair. Flow partially regulated by San Gabriel Elver flood-control 

dams Hos. 1 and 2 and Morris Dam. Water diverted near mouth of San Gabriel Canyon for Irrigation and spreading. Base data for Feb. 27 to Mar. 3 and entire record Feb. 1-26, Apr. 20, 27, and 29, furnished by Los Angeles County Flood Control 

District, through H. E. Hedger, chief engineer.

Mean dally discharge, in second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

27

12

154

118

58

37

30

26

42

50

Mar.

' 913

11,600

Apr. Day

11

12

13

14

15

16

17

18

19

20

Feb.

114

124

98

76

72

68

62

45

35

31

Mar. Apr.

*410

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

29

28

27

79

254

217

160

527

5,160

Mar. Apr.

«23

*17

* Discharge measurement.
230 FLOODS OF MA&CH 1938 IK SOUTHERN-CALIFORNIA

Page height, In feet, and discharge, In second-feet, at Indicated time, 19S6

»

1

2

3

4

5

er

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

6.00

6.01

6.02

6.02

6.04

6.09

6.10

5.79

5.66

5.64

5.55

5.50

5.49

5.49

5.48

222

224

227

227

235

254

258

154

118

113

91

82

78

78

74

Feet (See. ft.

February 28

5.51

5.66

5.96

6.41

 .88

6.99

6.93

6.97

6.96

6.92

6.92

6.79

6.69

' 6.60

6.55

6.58

6.84

7.48

7.88

78

113

207

402

708

793

746

769

761

730

730

635

566

501

464

483

656

1,220

1,710

Feet Sec. ft.

March 1

8.48

8.16

7.90

7.75

7.63

7.48

7.35

7.24

7.12

7.04

6.99

6.90

6.85

6.77

6.69

6.62

6.59

6.53

6.53

6.44

6.40

6.37

6.33

6.35

2,530

2,050

1,730

1,550

1,380

1,210

1,070

948

840

777

738

678

635

581

526

483

464

430

430

382

361

347

328

333

Feet | Sec. ft.

March 2

6.39

6.44

6.47

6.58

6.74

6.96

7.83

7.77

8.15

8.95

9.35

9.62

10.08

11.17

11.65

11.77

13.30

14.55

17.50

18.65

18.50

16.90

16.45

15.65

356

382

397

446

559

708

906

1,220

1,550

2,530

2,900

3,200

3,680

5,560

6,360

6,410

9,840

16,100

37,900

47,500

46,900

35,500

33,600

29.000

Feet | Sec. ft.

March 3

15.42 25,000

Feet Sec. ft.

March 4

Supplemental record.- Mar. 2, 7:35 p.m., 20.5 ft., 61,800 sec.-ft

San Gabriel River at Pico, Calif.

Location.- Water-stage recorder, lat. 340 00'20", long. 1180 04 I 05", in Paso de Bartolo 

grant, at Beverly Boulevard Bridge, half a mile east of Plco, Loa Angeles County. 

Altitude, about 180 feet.

Drainage area.- Area Indeterminate due to a natural split near Arrow Highway, which divides the San Gabriel River into two branches ; the west branch, known as the Rio 

Hondo, flows into the Los Angeles River; the east branch retains the name San Gabriel 

River.

Sage -height record.- Water-stage recorder graph except Mar. 4-6.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

12,700 second-feet; extended logarithmically to peak discharge on basis of a slopearea measurement of the peak. Discharge for period of missing gage-height record obtained from measurements and comparable hydrographs of adjacent streams.

Maxima.- 1938: 

1928-37:

Discharge, 22,700 second-feet 10:30 p.m. Mar. 2. 

Discharge, 22,000 second-feet Jan. 1, 1934.

Remarks . - Records fair. Flow partially regulated by San Gabriel River flood-control 

dams Nos. 1 and 2, Morris Dam, Big Dalton Creek, San Dlmas Oreek, Puddings tone, 

Live Oak Creek, and Thompson Oreek flood-control dams, and Puddingstone diversion 

dam. The City of Pasadena diverts water from the San Gabriel River at Morria Dam. 

There are also several diversions for irrigation. Records furnished by Los Angeles 

County Flood Control District, through H. E. Hedger, chief engineer.

Mean dally discharge, in second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

304

55

60

88

60

55

52

47

326

95

Mar.

2,040

11,400

6,080

3,190

1,420

1,030

916

1,270

2,030

1,050

Apr.

12

167

254

221

384

503

469

242

278

314

Day

11

12

13

14

15

16

17

18

19

20

Feb.

321

196

106

69

66

77

69

66

63

49

Mar.

615

1,020

759

704

597

386

203

254

278

221

Apr.

254

150

100

54

35

61

78

78

65

39

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

47

38

38

42

106

95

216

840

130

7,230

Mar.

121

115

176

314

384

384

134

78

121

140

70

1,210

74,380

Apr.

48

65

61

61

69

69

52

52

61

56

145

8,630
SAN GABfllBL RIVER BASIN

Page height. In feet, and discharge, ln second-feet, at Indicated time, 1938

h

1

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

11

Feet |3ec.ft.

February 27

Feet Sec. ft.

February 28

5.87

5.87

5.87

6.00

6.40

6.57

6.69

6.57

7.43

7.25

6.95

6.77

6.64

6.53

6.52

6.40

6.41

6.47

6.47

6.65

7.45

95

95

95

151

459

670

845

670

2,550

2,180

1,550

1,220

1,020

848

836

692

704

776

776

1,020

2,620

Feet Sec. ft.

March 1

9.00

9.30,

9.60

9.20

8.75

8.20

7.85

7.25

6.90

6.65

6.45

6.30

6.12

5.98

5.70

5.75

5,600

6,500

7,900

6,400

4,700

3,100

2,500

1,600

1,100

900

700

650

500

400

Feet Sec. ft.

March 2

5.76

5.78

6.10

6.70

7.57

8.60

9.45

9.90

10.12

10.85

10.52

10.05

10,20

10.08

9.90

10.55

11.45

11.35

11.00

11.25

11.02

400

400

800

2,000

. 4,200

7,400

9,800

9,800

13,400

14,200

11,800

10,700

11,400

lO'/OOO

11,400

16,400

19,200

17,400

16,400

18,300

20,300

22,000

20,000

il.600

Feet jsec.ft.

March 3

8,000

5,800

5,100

4,500

3,900

3,500

Feet Sec. ft.

March 4

San Gabriel River at Spring Street, near Los Alandtos, Calif.

Location.- Water-stage recorder, lat. 33°48 I 4011 , long. 118°05'3011 , in Los Alamltos

grant, at Spring Street Bridge, lj miles west of Los Alamltos, Orange Oounty. Altitude, about 22 feet.

Drainage area.- Area indeterminate due to a natural split near Arrow Highway, which divides the San Gabriel River into two branches; the west branch known as the Rio 

Hondo, flows into the Los Angeles River; the east branch retains the name of San 

Gabriel River.

Sage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation poorly defined; shifting-control correctlonsi used throughout period. Discharge Mar. 2, 3, 6, 8, and 11 determined by comparison with other stations. Maximum discharge determined by slope-area computation.

Maxima.- 1938: Discharge, 27,300 second-feet Mar. 2.

1928-37: Discharge, 15,000 second-feet Jan. 1, 1934.

Remarks.- See San Gabriel River at Plco for regulations and diversions. Maximum dlecharge determined by the Geological Survey; other records furnished by Los Angeles 

County Flood Control District, through H. E. Hedger, chief engineer.

Mean dally discharge, in second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

56

.8

0

3.0

0

0

0

0

156

75

Mar.

1,870

14,500

9,250

6,190

1,950

1,070

802

743

1,660

911

Apr.

5.5

0

5.5

35

95

210

248

270

166

188

Day

11

12

13

14

15

16

17

18

19

20

Mean monthly discharge, in second

Feb.

89

107

6

0

0

0

0

0

0

0

Mar.

248

690

416

440

312

202

142

112

109

112

Apr.

87

36

0

0

0

0

0

0

0

0

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

46

362

32.2 

1,790

Mar.

103

42

0

34

54

34

27

18

38

37

30

1,360 

83,600

Apr.

0

0

0

0

0

0

0

0

0

0

44.9 

2,670

454720 O - 42 - 16
232 FLOODS OF MARCH 1938 IN SOUEHERN CALIFORNIA

West Fork of San Gabriel River at Gamp Rincon, Calif.

Location.- Water-stage recorder, lat. 34*14'SO?, long. 117°51'50", near center of sec. 

19, T. 2 N., R. 9 W., a quarter of a mile above Gamp Rincon, and half a mile downstream from North. Fork of San Gabriel River. Altitude, 1,600 feet.

Drainage area.- Araa, 102 square miles. Average altitude, 4,260 feet. Maximum altitude, 8,840 feet. Average slope, 50 percent. Length of main atream channel, 14.4 

miles. Average slope of main stream channel, 8.7 percent.

Gage-height record.- Water-stage recorder graph except Mar. 2 to Apr. 4.

Discharge record.- Stage-diacharge relation fairly well defined. Discharge obtained 

by comparison with adjacent stations Mar. 2 to Apr. 4.

Maxima.- 1938: Discharge, 34,000 second-feet Mar. 2 (estimated). 

1927-37: Diecharge, 5,320 eecond-feet Jan. 1, 1934

Remarks.- Flow parti; regulated by flood-control dam upstream. Baee data and peak discharge for March and entire record for February and April furnished by Los Angeles 

County Flood Control District, through H. E. Hedger, chief engineer.

Mean daily discharge, in second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

136

69

322

448

231

151

117

102

166

181

Mar.

1,900

17,000

8,900

3,650

1,800

1,650

1,650

1,350

1,950

980

Apr.

330

330

320

315

320

302

276

241

212

180

Day

11

12

13

14

15

16

17

18

19

20

Feb.

598

441

280

218

179

156, 130-

139

151

126

Mar.

480

1,200

1,000

935

960

690

670

690

720

660

Apr.

177

186

186

182

164

164

158

156

152

150

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

115

111

108

106

102

100

197

1,310

12,890

Mar.

660

750

670

670

650

620

515

490

490

435

385

1,776

109,200

Apr.

144

140

135

146

150

142

132

122

130

124

196

11,640

Rogers Creek near Azusa, Calif.

Location.- Water-stage recorder, lat. 34°09'55", long. 117*54 '20*, in NWiNWi sec. 23, 

T. IN., R. 10 W. , half e mile above mouth of creek, and 2i miles north of Azuaa. 

Altitude, ebout 800 feet.

Drainage area.- Area, 6.4 square miles. Average altitude, 2,500 feet. Maximum altituda, 4,541 feet. Average slope, 50 percent. Length of main stream channel, 5.0

miles. Average slope cf main stream channel, 14 percent.

Page -height record.- Water-stage recorder graph except 7 a.m. Mar. Z to Mar. 15.

Diecharge record . - Stage-discharge relation defined by current-meter meaeuremente below 319 second-feet; extended logarithmically to peak die charge. Discharge for 

period of missing gage-height record determined from rainfall records, comparieon 

with nearby streams, and one discharge measurement.

Maxima.- 1938: Discharge, about 2,070 second-feet 4:30 p.m. Mar. 2. 

1917-37: Discharge, about 2,600 second-feet Apr. 7, 1926.

Remarks . - Recorde good except those for period of missing gage-height record, which 

are poor. Diversions above gage at times.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

11

5.5

131

50

20

11

9.5

9

18

16

Mar.

233

738

202

108

86

62

45

41

41

38

Apr.

15

15

15

15

15

15

15

14

14

13

Day

11

12

13

14

15

16

17

18

19

20

Feb.

54

42

23

19

17

9.5

8

8

8.5

7

Mar.

28

87

85

75

69

62

51

44

37

34

Apr.

13

14

14

12

11

11

10

9.5

9.5

9.5

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

6

6

5.5

4.9

4.9

4.7

8.5

212

26.1

1,450

Mar.

30

28

25

24

23

22

19

19

18

17

16

4,770

Apr.

9.5

9.5

9

9.5

10

9.5

9

8.5

9

9

11.7

698
3AH QABRIBL RIVBH BASIN 233

flag* height, in foot, and discharge. In second-feet, at indicated time, 1988

HOUF

1

2

3

4

6

6

7

8

9

10

11

H

1

2

3

4

6

6

7

8

9

10

11

11

Feet | 8«e. ft t

February 28

2.91

3.02

3.23

3.62

3.80

3.96

4.06

4.93

4.89

6.10

6.10

6.27

6.28

6.23

6.12

4.96

4.88

4.78

4.76

4.76

4.86

6.62

6.47

6.90

14

20

36

62

91

113

128

242

837

269

269

299

314

316

300

270

864

236

£87

220

226

306

442

601

Feet

Hi

6.96

6.67

6.34

6.97

6.97

6.67 ,

6.62

6.38

6.21

6.08

4.94

4.86

4.74

4.70

4.68

4.49

4.48

4.38

4.36

4.33

4.32

4.32

4.32

4.29

Seo.ft.

iron 1

612

461

391

336

336

892

272

264

233

218

201

190

177

172

169.

149

142

187

136

131

130

130

130

127

Feet i s*o. ft.

March 2

4.36

4.46

4.60

4.66

4.86

6*23

6.76

136

146

160

168

190

236

304

Plih Oreek near Duarte, Oalif.

Location.- Water-stage recorder, lat. 34*10*00", long. 117e 66'26n , in SWfcBWi sec. 16, 

T^IK., R. 10 1., three-quarter! of a ail* abort mouth of canyon, and 3 miles 

northeait of Duarte. Altitude, about 1,000 feet.

Drainage area.- Area, 6.6 square miles. Average altitude, 2,760 feet. Maximum altltude, e,3BO feet. Average slope, 46 percent. Length of main stream channel, 4.7 

miles. Average slope of main stream channel, 17.6 peroent.

Page-height record.- Recorder not in operation during flood. Daily staff-gage readings obtained after Mar. 16.

Discharge record.- Discharge prior to Mar. 16 estimated from current-outer measurements, rainfall records, and by comparison with nearby streams. Peak discharge determined from rainfall-runoff studies. After Mar. 16 discharge determined from rating curve defined by current-meter measurements.

Maxima.- 19381 Discharge, about 2,100 second-feet about 6 p.m. Mar. 2, from rainfallrunoff studies.

1916-371 Discharge, about 2,180 second-feet Apr. 4, 1926.

Remarks.- Records poor. Ho regulation or diversions.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

6

6

7

8

9

10

Feb.

19

9

140

69

83

12

11

10

20

18

Mar.

267

762

303

136

96

70

61

62

44

36

Apr.

24

23

23

20

22

20

19

19

19

18

Day

11

12

13

14

16

16

17

18

19

20

Mean monthly discharge, in second

Feb.

66

46

26

21

19

12

8.6

9

9.6

7.6

Mar.

33

90

80

68

68

62

49

46

46

41

Apr.

16

17

16

16

18

13

12

11

11

11

Day

21

22

23

24

26

26

87

28

89

30

31

Feb.

6.6

6.6

6

6.6

6.6

6

9

190

27.4 

1,620

Mar.

40

37

34

33

30

30

28

88

87

26

86

87.6 

6,390

Apr.

11

11

11

12

- 13

11

10

101111

16.8 

908
234 FLOODS OF MARCH 1958 IN SOUTHERN CALIFORNIA

Sawpit Creek near Monrovia, Calif.

Location.- Water-stage recorder and broad-crested weir control, lat. 34°10'20*, long.

 n7*r59'25", in MWjSWi sec. 13, T. 1 H., R. 11 W., 0.2 mile downstream from confluence of two main branches, and 2 miles north of Monrovia. Altitude, about 1,100 

feet.

Drainage area.- Area, 5.7 square miles. Average altitude, 3,050 feet. Maximum altltude, 5,390 feet. Average slope, 50 percent. Length of main stream channel, 3.6 

miles. Average slope of main stream channel, 14 percent.

Page-height 25-307 record.- Water-stage recorder graph Feb. 1-11 and Apr. 12, 16-23, and 

Discharge record.- Stage-discharge relation well defined within the range of use. Concrete control and station destroyed Mar. 2. Discharge for Feb. 12 to Apr. 11, Apr. 

13-15, and 24 determined from hydrograph based on records at flood-control dam and 

five discharge measurements.

Maxima.- 1938: Discharge, about 1,800 second-feet Mar. 2, computed on basis of Inflow 

to flood-control reservoir above gage.

1916-37: Discharge, about 8,000 second-feet Apr. 7, 1926, estimated from flow of 

Rogers Creek.

Remarks.- Records fair. Flow partly regulated by operation of flood-control dam about 

mile upstream.

Msan daily discharge, in second-feet, 1958

Day

1

2

5

4

5

6

7

8

9

10

Feb.

1.1

.5

11

19

9.5

8

5

8

10

1.5

Mar.

114

450

255

108

92

91

76

57

25

24

Apr.

15

13

15

15

12

12

12

12

11

11

Day

11

12

13

14

15

16

17

18

19

20

Feb.

14

11

11

10.5

7

5

4.5

3.5

1.8

1.4

Mar.

22

41

34

50

26

24

22

20

19

18

Apr.

10

10

10

10

10

9

9

9

9

9

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

1.0

.9

.8

.8

.7

.6

10

89

8.82

490

Mar.

17

16

18

14

15

15

15

15

14

14

15

55.7

5,500

Apr.

9

8.5

8

7.5

7

6

6

6

6

7

9.60

571

San Dimas Creek near San Dimas, Calif.

Location.- Water-stage recorder and broad-treated weir control, lat. 34°08 t 45n > long. 

 n7T6'55", In SWtNEi aeo. 25, T. 1 H., R. 9 W., at mouth of San Dimas Canyon, 3 

miles northeast of San Dimas. Altitude, about 1,245 feet.

Drainage area.- Area, 18.3 square miles. Average altitude, 3,130 feet. Maximum altltude, 5,558 feet. Average slope, 42 percent. Length of main stream channel, 7.5 

miles. Average slope of main stream channel, 10 percent.

Page-height record.- Water-stage recorder graph except Feb. 18-27 and Mar. 20-87.

Discharge record.- Stage-dischargs relation well defined below 250 seccnd-feet prior to 

Mar. 2j on Mar. 2 control was partly destroyed. Dlsohargs Feb. 18-27, Mar. 2-9 and 

£0-27, determined from outflow from flood-control reservoir.

Maxima.- 1938s Discharge, 4,250 second-feet 6 p.m. Mar. 2.

1914, 1916-37! Discharge, 2,950 second-feet February 1914.

Remarks.- Records good. Flow almost completely regulated by flood-control reservoir 

0.7 mile upstream.

Mean daily discharge, in second-feet, 1958

Day

1

2

5

4

5

6

7

8

9

10

Feb.

1.6

.5

1.7

2.0

1.2

.9

.7

.6

1.7

1.5

Mar.

281

1,540

750

540

210

110

96

65

62

42

Apr.

27

26

25

25

25

25

25

25

25

25

Day

11

12

15

14

15

16

17

18

19

20

Feb.

2.B

8

15

15

15

12

12

11

10

8

Mar.

56

88

115

127

117

95

90

47

93

70

Apr.

24

24

9.5

2.1

2.1

2.2

2.2

2.2

2.4

2.4

Day

21 22

23

24

25

26

27

28

29

30

31

Feb.

6

5

4

2

1

2

15

87

482

Mar.

57

57

53

49

48

46

59

53

33

35

32

9,230

Apr.

2.4

2.3

2.4

2.8

2.7

1.8

4.0

10

14

14

12. B

75.9
SAN GABRIEL RIVER BASIN

Dalton Creek near Qlendora, Calif.

Location.- Water-stage recorder and concrete control, lat. 34°C9 I 2011 , long. 117°49'50", 

In center of sec. 21, T. IN., R. 9 W., at Qlendora Irrigation Co.'s dam, a quarter 

of a mile above mouth, and 2$ miles northeast of Qlendora. Altitude, about 1,150 

feet.

Drainage area.- Area, 7.5 square miles. Average altitude, 2,440 feet. Maximum altltude, 3,686 feet. Average slope, 42 percent. Length of main stream channel, 5.0 

miles. Average slope of main stream channel, 10 percent.

Qage-height record.- Water-stage recorder graph except Feb. 25-27 and Mar. 24-28.

Discharge re cord.- Stage-discharge relation well defined by current-meter measurement* 

below 80 second-feet. Discharge Feb. 25-27 Interpolated. Discharge Mar. 2-7 determined by release from flood-control reservoir and computed runoff for area between flood-control dam and gaging station. Discharge Mar. 24-28 taken from comparative hydrograph based on four discharge measurements, release from flood-control 

reservoir, and estimated inflow between dam and gage.

.- 1938: Discharge, about 850 second-feet 5 p.m. Mar. 2 (gage height, 4.90 feet). 

1914, 1919-37: Discharge, 1,070 second-feet February 1914.

 ka.- Records good except those for Mar. 2-7, which are fair, 

.ocated about 1 mile upstream.

Flood-control dam

Mean dally discharge, In seephd-feet, 1988

Day

I

2

3

4

5

6

7

8

9

10

Feb.

0.9

.3

1.2

1.3

.9

.6

.4

.3

1.0

.8

Mar.

28

266

219

193

122

112

76

70

54

50

Apr.

9

8

8

8

8

7.5

7.S

7

5

3.1

Day

11

12

13

14

16

16

17

18

19

30

Feb.

2.3

3.0

' 2.4

2.2

1.7

1.0

.6

.5

.8

.4

Mar.

30

37

28

28

30

30

40

33

27

23

Apr.

3.0

2.7

2.3

1*8

1.6

1.6

1.4

1.3

1.4

1.4

Day

21

22

23

24

26

26

27

28

89

30

31

Feb.

0.3

.3

.3

.2

.2

.1

.1

14

1.36

76

Mar.

23

22

16

12

10

10

13

16

12

11

10

53.2

3,270

Apr.

1.6

1.4

1.4

1.6

2.6

2.6

2.1

1.4

1.5

1.6

3.68

213

Page height, in feet, and discharge, in second-feet, at indicated time, 1938

1

1

2

3

4

6

6

7

8

9

10

11

N

1

2

3

4

6

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

^

Feet Seo.ft.

February 28

2.32

2.32

2.32

2.32

2.28

2.25

2.25

2.23

2.18

2.17

2.16

2.16

2.25

2.47

2.50

2.65

0.1

.1

.1

.1

.1

.1

.1

.1

19

19

19

19

13

9.8

9.8

9.5

8.8

8.5

8.2

8.2

21

39

42

68

Feet Sec. ft.

March 1

2.60

2.44

2.47

2.46

2.44

2.45

2.40

2.41

2.45

2.46

2.46

2.48

68

30

34

33

30

31

24

26

31

33

33

38

Feet Sec. ft.

March 2

2.49

2.60

2.51

2.52

2.62

2.52

2.69

2.68

2.76

2.88

2.80

2.75

2.83

2.96

3.35

3.85

4.70

4.70

4.40

4.40

4.40

4.25

4.15

3.90

41

42

54

55

55

55

57

75

93

121

100

90

109

144

267

485

850

800

620

590

580

450

445

350

Feet See. ft.

March 3

2.95

2.80

2.69

2.60

2.51

2.47

2.42

2.38

2.37

2.36

2.41

2.40

2.38

2.39

2.50

2.41

2.57

2.60

2.48

2.52

2.56

2.55

2.51

3.85

255

255

252

242

201

170

190

213

215

213

197

182

177

172

229

187

183

218

214

208

204

200

300

405

Feet See. ft.

March 4

4.05

4.00

3.95

3.80

3.65

3.50

3.40

400

395

390

385

380

376

370

180

40

38

120

195

180

164

90

90

60

90

90

90

90

90

90

90
256 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Little Dalton Creek near Olendora, Calif.

Location.- Water-stage recorder, lat. 34°09'30n , long. 117°50'15", In SBj sec. 20, T. 

1 H., R. 9 W., 500 feet above mouth of Little Dalton Canyon, and 2 miles northeast 

of Olendora. Altitude, about 1,110 feet.

Drainage area.- 3.3 square miles.

Page-height record.- Water-stage recorder graph except 7 p.m. Mar. 2 to Mar. 12.

Discharge record.- Stage discharge relation defined by current-meter measurements below 

151 second-feet; extended logarithmically to peak discharge as determined by a slopearea measurement. Discharge for periods of missing record estimated from discharge 

measurements and records of inflow to flood-control reservoir on Dalton Creek.

Maxima.- 1938: Discharge, 960 second-feet 4:55 p.m. Mar. 2 (gage height, 5.9 feet). 

1914, 1929-37: Discharge, 1,020 second-feet February 1914.

Remarks.- Records fair. Small diversion above station. Record furnished by Los 

Angeles County Flood Control District through H. E. Hedger, chief engineer.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

2.0

.8

9.5

5.5

3.0

2.1

1.8

1.5

3.3

1.6

Mar.

81

381

105

66

30

23

18

18

17

12

Apr.

6.5

6

6

6

5.5

5

4.8

4.8

4.5

4.5

Day

11

12

13

14

15

16

17

18

19

20

Mean monthly discharge, In second

Feb.

6.0

5.5

4.2

3.2

2.6

2.4

1.9

2.1

2.6

1.8

Mar.

12

31

30

22

20

19

16

15

15

14

Apr.

4.3

4.3

4.3

4.1

3.8 *3.e

3.3

3.1

3.1

3.6

Day

21

22

25

24

26

26

27

28

29

30

31

Feb.

1.5

1.3

1.2

1.1

1.0

1.0

3.7

45

4.26 

236

Mar.

13

12

12

10

9.5

9

8.5

8.5

8

7.5

7

33.9 

2,080

Apr.

3.3

2.6

2.6

3.3

4.3

3.8

3.3

3.1

2.9

3.6

4.14 

246

Page height, In feet, and discharge. In second-feet, at Indicated time, 1938

w

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet) Sec. ft.

February 27

0.48

.50

.65

.57

.55

.53

.55

1.4

1.6

6.0

3.7

3.2

2.8

3.2

Feet Seo.ft.

February 28

0.72

.91

.95

2.03

1.30

1.31

1.25

1.15

1.36

.96

.96

1.12

1.65

2.05

2.36

8.3

17.8

19.7

148

46

47

42

33

52.0

34

23

19

19

30

87

149

205

Feet Sec. ft.

March 1

3.08

2.45

2.23

2.05

1.60

1.47

1.20

1.26

346

214

169

132

90

63

52

49

 44

39

35

24

18

15

19

Feet Seo.ft.

March 2

1.42

1.53

1.95

2.50

3.24

3.36

3.36

4.04

4.05

4.70

5.40

5.00

48

66

132

234

387

412

412

559

561

700

851

765

Feet | Sec. ft.

March 3

-

Feet Sec. ft.

March 4

Supplemental record.- Mar. 2, 4:55 p.m., 5.9 ft., 960 sec.-ft.
SAN GABRIEL RIVER BASIN & 

Walnut Creek near Baldwin Park, Calif.

Location.- Water-stage recorder, lat. 34°03'55", long. 117°59'00", In La Puente grant, 

at Oovlna Boulevard, near Baldwin Park, Los Angeles County. Altitude, about 335 

feet.

Drainage area.- 99 square miles.

Page-height record.- Water-stage recorder graph except 2 a.m. Mar. 3 to 12 m. Mar. 7. 

Gage heights estimated from occasional staff-gage readings for period of missing 

record.

Discharge record.- Stage-discharge relation defined by 13 current-meter measurements, 

made during period Feb. 27 to Mar. 3, up to 4,200 second-feet and extended above.

'Maxima.- 1938: 

1928-37:

Discharge, 4,290 second-feet 5 p.m. Mar. 2 (gage height, 

Discharge, 8,060 second-feet Jan. 1, 1934.

5.50 feet).

Remarks.- Records good. Flow partially regulated by Dalton, San Dimas, Puddingstone 

diversion, Puddlngstone, Live Oak, and Thompson Creek Dams. Some water diverted 

for Irrigation at Puddlngstone Dam. Records furnished by Los Angeles County Flood 

Control District, through H. E. Hedger, chief engineer.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

93

0

5.5

1.2

0

0

0

0

70

0

Mar.

443

2,580

517

253

117

123

45

124

110

89

Apr.

0.4

0

.2

.2

0

.2

.8

.8

.2

.2

Day

11

12

13

14

15

16

17

18id

20

Feb.

85

35

0

0

0

0

0

0

0

0

Mar.

36

94

35

99

89

103

89

45

64 '

86

Apr.

0

2.8

2.8

2.4

2.4

1.2

2.8

1.1

.6

1.1

Da*

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

20

406

25.6

1,420

Mar.

69

64

86

64

33

20

17

3.6

.8

.4

.4

10,900

Apr. .

1.4

2.8

2.8

0

.6

0

.1

0

0

.9

57

gage height, In feet, and discharge, In second-feet, at Indicated time, 1958

ftt

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7'

8

9

10

11

M

Feet) Sec. ft.

February 27

2.10

2.47

2.80

2.70

2.55

2.33

2.20

0

0

0

0

0

0

0

0

0

2.8

50

170

124

69

37

14

0

0

0

0

0

Feet Sec. ft.

February 28

2.38

2.80

2.92

3.30

4.40

3.90

3.25

2.90

2.53

2.40

2.30

2.24

2.22

2.25

2.32

4.12

4.38

0

0

0

0

61

283

385

795

2,370

1,510

665

342

79

44

18

12

7.5

11

17

1,420

1,790

Feet Sec. ft.

March 1

5.10

5.10

4.10

3.25

3.00

2.90

2.62

2.46

2.38

2.33

2. 29

2.22

2.20

2.14

2.18

2,900

2,950

1,400

474

310

251

125

75

56

43

35

24

20

13

18

Feet Sec.ft.

March 2

2.36

2.56

2.84

3.10

3.59

4.38

5.10

5.38

5.68

5.60

5.50

5.00

4.60

4.91

5.30

5.50

5.50

5.40

5.15

4.50

4.27

4.00

3.60

3.10

58

132

283

174

840

2,060

3,250

3,730

4,230

4,080

3,890

3,300

2,470

2,710

3,780

4,200

4,290

4,180

3,810

2,760

2,370

2,130

1,550

904

Feet Sec.ft.

March 3

3.00

2.96

2.91

2.85

3.34

2.91

2.74

2.45

2.31

2.27

2.24

2.30

2.21

2.23

805

790

740

705

1,300

1,110

615

378

283

251

220

271

185

193

Feet Seo.ft.

March 4
238 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

San Jose Creek near Whittier, Calif.

Location.- Water-stage recorder, lat. 34°01'25", long. 118°02'05", in Paso de Bartolo 

grant, at Workman-Mill road bridge, and about 3 miles north of Whittier, Los Angeles 

County. Altitude, about 230 feet.

Drainage area.- 85.2 square miles.

gage-height record.- Water-stage recorder graph except April 21-29.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 7,500 second-feet; extended logarithmically to peak discharge. Discharge for 

period of missing gage-height record based on current-meter measurements.

Maxima.- 1938: Discharge, 9,350 second-feet 4:40 p.m. liar. 2 (gage height, 10.3 feet).. 

1929-37: Discharge, 13,100 second-feet Jan. 1, 1934.

Remarks.- Flow partially regulated by Thompson Creek Dam. Several small diversions. 

Records furnished by Los Angeles County Flood Control District, through H. E. Hedger, 

chief engineer.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

156

6.0

4.4

31

2.4

.8

.8

.8

193

26

Mar.

769

4,380

505

115

32

9

3.9

3.9

4.4

3.9

Apr.

1.3

1.3

1.6

1.3

1.4

1.3

1.4

2.3

1.6

1.1

Day

11

12

13

14

15

16

17

18

19

20

Feb.

165

81

14.0

2.1

1.0

.8

.7

.7

.8

.8

Mar.

5.4

342

55

23

7

4.4

2.3

1.6

1.6

1.6

Apr.

1.6

8.3

2.3

1.8

1.8

2.3

1.3

1.1

1.6

1.8

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0.9

.9

.9

2.0

2.7

1.3

86

340

40.1

2,230

Mar.

1.6

1.6

1.6

1.6

1.6

1.6

1.8

1.4

1.6

1.3

1.3

OA1*

12,470

Apr.

1.8

1.9

1.9

2.1

2.1

2.2

2.2

2.2

2.3

2.3

I

rfQ

106

Page height, in feet, and discharge, in second-feet, at indicated time, 193S

s

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

FeetjSec.ft.

February 27

2.06

2.10

2.20

2.70

3.55

3.85

3.80

3.55

3.18

2.80

3.0

4.4

9

38

190

265

223

155

76

27

Feet Sec.ft.

February 28

2.68

3.40

3.95

4.05

4.00

4.18

4.10

4.33

4.10

3.55

3.30

3.90

6.10

6.90

12

125

293

337

329

406

378

496

406

205

145

290

1,670

2.410

Feet Sec.ft.

March 1

7.10

7.55

7.00

6.40

5.70

5.10

4.70

4.25

3.70

3.32

3.05

2.80

2.60

2.52

2.52

2,490

2,900

2,310

1,730

1,170

782

588

432

276

180

113

68

41

32

32

Feet Sec.ft.

March 2

2.52

4.05

5.00

6.40

7.30

7.80

9.40

9.75

10.25

9.00

8.50

8.20

8.40

9.40

9.50

8.90

8.20

7.50

5.30

4.75

32

424

936

2,190

3,300

3,960

6,940

7,580

8,880

6,120

5,160

4,600

5,060

7,080

7,380

6,180

4,800

3,630

1,190

896

Feet | Sec. ft.

March 3

4.55

3.60

3.30

3.55

4.26

3.92

4.10

4.00

3.52

3.40

3.32

3.00

2.90

2.93

2.88

872

515

355

488

968

724

850

780

471

405

365

225

187

198

181

Feet See. ft.

March 4

*

Supplemental record.- Mar. 2, 4:40 p.m., 10.3 ft., 9,350 sec.-ft.
SAN GABRIEL RIVER BASIN 239

Coyote Creek near Artesla, Calif.

Location.- Water-stage recorder, lat. 33°50'45", long. 118°03'30", In Coyote grant, on 

line between Orange and Los Angeles Counties, Just above Pacific Electric Railway 

bridge 2& miles southeast of Artesla. Altitude, about 35 feet.

Drainage area.- 110 square miles.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 3,580 second-feet; extended logarithmically to peak stage.

Maxima.- 1938$ Discharge, 4,000 second-feet 8 p.m. Mar. 2 (gage height, 12.15 feet). 

1929-37: Discharge, 4,190 second-feet Feb. 6, 1937 (gage height, 1C.1 feet).

Remarks.- Records good. No regulation or diversions. Records furnished by Los Angeles 

(County Flood Control Dietrict, through H. E. Hedger, chief engineer, and by Corps of 

Engineers, TJ. S. Army.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

7.5

22

4.0

4.4

7.5

6.5

2.2

1.2

131

149

Mar.

886

2,540

2,840

228

69

38

23

18

14

13

Apr.

2.2

2.0

2.2

2.0 2.0

2.2

2.4

1.9

1.4

1.3

Day

11

12

13

14

15

16

17

18

19

20

Feb.

37

94

32

11

4.4

2.4

1.8

1.2

1.4

1.9

Mar.

8.5

156

80

32

13

6

6

4.4

4.4

4.2

Apr.

1.3

1.2

1.0

.8

.8

.7

.6

.6

.5

.5

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

1.8

1.3

1.0

.8

.7

.6

8.5

109

23.1

1,280

Mar.

4.2

3.2

4.0

4.2

4.2

4.2

3.2

3.0

3.2

3.4

2.7

or>*7

13,930

Apr.

0.5

.5

.5

.7

1.3

1.6

1.0

.8

.8

1.4

1.22

73

Gage height, in feet, and discharge, in second-feet, at indicated time, 1938

w

l

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

3.45

3.46

3.47

3.55

3.59

3.71

3.79

3.83

3.84

4.18

4.45

4.54

4.55

0.3

.3

.3

.6

.7

1.0

2.9

4.2

4.5

25

53

64

66

Feet | Sec. ft.

February 28

4.55

4.51

4.45

4.32

4.30

4.70

4.95

5.10

5.13

5.15

5.14

5.95

5.11

5.05

5.05

5.13

5.55

66

60

53

39

37

88

130

160

166

170

168

162

150

150

165

265

Feet jsec.ft.

March 1

6.33

7.00

7.65

8.12

8.68

8.96

8.93

8.85

8.75

8.45

8.02

7.55

7.15

6.75

6.40

6.15

5.95

5.80

5.70

5.57

5.45

5.35

5.27

5.22

510

780

1,110

1,360

1,700

1,880

1,860

1,800

1,730

1,540

1,300

1,050

850

670

520

450

380

330

305

270

240

215

200

185

Feet | Sec. ft.

March 2

5.20

5.20

5.35

5.60

6.10

6.92

7.88

8.73

9.74

10.38

10.96

11.34

11.69

11.88

11.95

11.96

11.95

12.02

12.06

12.15

12.04

12.05

12.05

11.99

180

180

215

280

415

655

1,220

1,700

2,350

2,760

3,150

3,400

3,650

3,780

3,850

3,870

3,850

3,890

3,910

4,000

3,890

3,900

3,900

3.880

Feet | Sec. ft.

March 3

11.90

11.81

11.55

11.05

10.25

10.00

9.85

10.50

11.35

11.65

11.74

11.75

11.67

11.45

11.09

10.59

9.58

8.58

7.82

7.57

3,750

3,700

3,500

3,050

2,490

2,300

2,200

2,660

3,300

3,600

3,670

3,680

3,620

3,400

3,100

2,700

2,000

1,420

1,025

910

Feet Sec. ft.

March 4

6.80

6.54

5.86

5.71

5.60

5.50

5.29

5.29

5.18

5.08

4.98

4.89

4.79

4.73

4.89

605

500

310

275

245

220

178

178

156

137

120

105

90

82

7ft
240 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Brea Creek at Fullerton, Calif.

Location.- Water-stage recorder, lat, 33*52 "25", long. 117"55'40", in San Juan Cajon de 

Santa Ana grant, at Ford Avenue Bridge, at Fullerton, Orange County. Altitude, about 

250 feet.

Drainage area.- Area, 26.4 square miles. Average altitude, 800 feet. Maximum altltude, 1,476 feet. Average slope, 21 percent. Length of main stream channel, 16 

miles. Average slope of main stream channel, 1.5 percent.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation fairly well defined by measurements below 

250 second-feet and extended above on basis of slope-area determinations.

Maxima.- 1938: Discharge, 1,970 second-feet Mar. 2 (gage height, 9.55 feet). 

 1930-37S Discharge, 1,600 second-feet Oct. 17, 1934 (gage height, 7.60 feet).

Remarks.- Records furnished by Orange County Flood Control District, through II. N. 

Thompson, chief engineer.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

8.5

0

.6

.8

0

0

0

0

59

12

Mar.

157

944

22

1.8

.9

.5

.2

.1

.1

.1

Apr.

0

0

0

0

0

0

0

0

0

0

Day

11

12

13

14

15

16

17

18

19

20

Feb.

8

8.5

.4

0

0

0

0

0

.1

0

liar.

0.1

2.4

.4

.2

0

0

0

0

0

0

Apr.

0

0

0

0

0

0

0

0

0

0

Day21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

6.5

50

306

Mar.

0

0

0

0

0

0

0

0

0

0

0

36.4

2,240

Apr.

0

0

0

0

0

0

0

0

0

0

0

0

Gage height, In feet, and discharge, in second-feet, at Indicated time, 1938

s

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

0.90

.83

1.40

1.24

1.27

1.33

1.40

1.50

1.48

1.40

1.34

1.28

1.22

1.14

1.09

1.00

1.00

0

0

0

0

0

0

0

1.8

1.2

14

7.5

8.5

11

15

20

20

16

13

10

8.5

6

5

3.6

3.7

Feet | Sec. ft.

February 28

1.00

.96

.90

.86

1.05

1.86

1.90

1.90

1.83

1.82

1.82

1.83

1.77

1.73

1.72

1.69

1.62

1.60

1.56

1.60

2.05

2.40

2.55

3.10

3.9

3.4

2.8

2.4

5

50

54

54

49

49

50

50

47

44

44

42

38

36

34

37

74

113

136

230

Feet Sec.ft.

March 1

4.65

4.26

3.60

3.11

3.32

3.06

3.12

2.80

2.50

2.18

2.12

2.03

1.95

1.85

1.78

1.72

1.66

1.59

1.53

1.47

1.42

1.39

1.42

1.75

580

490

330

240

280

230

240

180

140

95

89

79

74

67

64

61

57

55

52

50

49

49

53

88

Feet Sec.ft.

March 2

1.90

2.12

2.20

3.00

5.00

6.93

6.60

5.80

6.38

6.79

6.30

5.78

6.40

9.00

8.70

6.80

8.50

7.32

5.90

4.50

4.10

3.60

3.00

2.38

62

90

102

280

870

1,450

1,350

1,100

1,280

1,410

1,260

1,100

1,280

1,910

1,860

1,420

1,830

1,560

1,140

720

600

450

280

140

Feet Sec.ft.

March 3

1.90

1.50

1.20

1.00

.82

1.60

1.92

1.50

1.17

.97

.93

1.00

.91

.80

.77

.73

.70

.68

.65

.62

.60

.58

.56

.53

62

35

22

14

9

40

64

35

21

13

12

14

11

8.5

8

7

6.5

6

5.5

5

4.6

4.3

4.0

3.5

Feet Sec.ft.

March 4
SAN OABRHSL RIVXR BASIN 841

Carbon Creek at Ollnda r Calif.

Location.- Water-stage recorder, lat. 33*83 "SO", long. 117°BO'40", In San Juan Oajon 

'de Santa Ana grant, at Oolden Avenue Bridge, It miles south of Ollnda, Orange County. 

Altitude, 368 feet.

DraiBaae area.- Area, 20.C square miles. Average altitude, 1,010 feet. Maximum altitune, i,7BQ feet. Average slope, 30 percent. Length of aaln stream channel, 9.5 

alles. Average slope of main stream channel, 1.9 peresnt.

stage

- Water-stage recorder graph to Mar. 1) no record thereafter. Peak

Eoodmarks.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

410 seoona-reet, and extended to peak stage on basis of slops-area determinations.

- 1938t Discharge, 1,760 second-feet Mar. 2 (gage height, 4.0 feet). 

930-37t Discharge, 788 seoond-feet Jan. 1, 1984.

Remarks.- Record furnished by Orange tfounty Flood Control District, through M. N. 

Thompson, chief engineer.

Mean daily discharge, in seeoad-feet, 1988

Day

l

8

S

4

5

6

7

B

9

10

Feb.

8.8

0

.2

1.0

0

0

0

0

7

3.8

Mar.

46

Apr. Day

11

IB

13

14

15

16

17

18

19

20

Mean monthly discharge, in second

Feb.

B

3.5

0

0

0

0

0

0

0

0

Mar. Apr. " r

81

88

88

84

85

8«

87

88

89

80

31

Feb.

0

0

0

0

0

0

8.8

16

1.56 

B6

Mar. Apr. .

Page height, In feet, and discharge, In second-feet, at indicated time, 1988

I

1

2

3

4

8

6

7

B

9

10

11

N

1

8

3

4

6

6

7

8

9

10

11

M

Fest|8eo.ft.

February 87

-0.86

.05

- .10

- .80

.80

.80

.18

.06

.06

.06

.01

.09

.17

.16

.21

.80

Feet Beo.ft.

February 28

-0.26

.10

.03

.06

.20

.30

.30

.89

.16

.IB

.80

.86

.88

.14

.09

.09

0

.10

.38

.38

.70

1.10

0

0

0

6.5

4.6

6.6

10

16

15

14

8.6

9.6

10

13

11

B

6

6

3.7

6.5

82

88

66

114

Feet |&eo.ft.

March 1

1.40

8.60

1.00

.68

.60

.43

.39

.34

.31

.89

.86

.83

.81

.80

.19

.18

.16

.16

.13

.18

.11

.11

.18

.86

164

466

99

63

38

86

88

IB

16

16

13

18

11

10

9.6

9.6

B.6

B.6

7.6

7

7

7

7

13

Feet &eo.ft.

March 8

Feet See. ft.

March 3

Feet | Sec. ft.

March 4
242 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 

Los Angeles River Basin

Los Angeles River near Van Nuys, Calif.

Location.- Water-stage recorder, lat. 34°09'30", long. 118°26'55", in Ex Mission San 

Fernando grant, on Van Buys BouleVard Bridge, about 2 miles south of Van Hays, Los 

Angeles County. Zero of gage is 635.75 feet above mean sea level.

Drainage area.- 157 square miles.

Page-height record.- Water-stage rscorder graph Feb. 1 to 2s30 p.m. Mar. 2j peak stage 

observed on staff gage.

Discharge record.- Stage-discharge relation defined by six discharge measurements made 

Feb. 27 to Mar. 2.

Maxima.- 1928-37! 1938i Discharge, 

Discharge.

11,600 aecond-feet 5 p.m. Mar. 2. 

7,380 second-feet, Jan. 1, 1934.

Remarks.- Flow slightly regulated by Chatsworth Reservoir, Upper and Lower San Fernando 

Reservoirs, Twin Lakes Dams, dam on tributary of Limekiln Creek, andEncino Reservoir. 

Peak discharge determined by the Geological Survey, other records furnished by Loa 

Angeles County Flood Control District, through H. E. Hedger, chief engineer. 

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

211

10

58

50

8.5

6.5

6.5

7

73

20

Mar.

974

5,870

Apr. Day

11

12

13

14

15

16

17

18

19

20

Mean monthly discharge, In second

Fsb.

477

45

11

9

8

8

7.5

8

10

7.5

Mar. Apr. Day

21

22

23

24

25

26

27

28

29

30

31

-feet.......................

Feb.

7

7

6.5

6.5

6

6

45

509

58.4 

3,240

Mar. Apr.

11

11

Qsge height, in feet, snd discharge, In second-feet, at Indicated time, 1988

S

1

2

3

4

5

6

7

8

9

10

11

H

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec.ft.

February 27

1.76

2.16

2.64

2.99

3.17

3.62

3.71

3.60

3.10

2.90

11

20

35

50

58

84

90

.90

105

94

83

70

63

57

54

50

45

Feet Sec.ft.

February 28

2.72

2.60

3.60

5.00

6.54

6.70

7.03

6.25

5.30

6.15

9.56

10.15

10.55

41

37

33

45

64

50

100

160

225

550

600

680

720

640

550

450

380

290

200

170

420

2,000

2,400

2,700

Feet Sec.ft.

March 1

5.00

5.47

5.85

6.15

6.39

6.45

6.59

6.65

6.03

2,900

3,080

3,100

2,700

2,450

2,150

1,500

800

540

400

320

280

250

220

180

160

150

140

130

120

100

100

110

170

Feet Sec.ft.

March 2

250

280

500

1,350

2,250

3,300

4,4JOO

4,900

6,100

6,700

6,900

7,500

9,600

10,700

Feet Sec.ft.

March 3

Feet Sec.ft.

March 4
LOS AHOELES RIVER BASIH 243

Los Angeles River neap Universal City, Calif.

Location.- Water-stage recorder, lat. 34°08'35", long. 1180 22->10" , In Ex Mission San 

Fernando grant, at Vineland AVenue Bridge, near Universal City, Los Angeles County. 

Altitude, about 550 feet.

Dra area.*- After leaving Its canyon, Tujunga Creek splits Into two normally dry

washes, one of which, known as Tujunga Wash, enters Los Angeles River upstream from 

this station and the other downstream. The drainage area of Los Angeles River, exclusive of Tujunga Creek Basin above the split (157 square miles), Is 245 square 

miles.

gage-height record.- Water-stage recorder graph 7 a.m. Feb. 27 to 8»50 a.m. Mar. 2.

Discharge record.- Stage-discharge relation defined by four current-meter and two float 

measurements, made during period Feb. 27 to Mar. 2, and a slope-area measurement of 

the peak.

Maxima.- 1938: Discharge, 37,700 second-feet Mar. 2.

1930-36: Discharge, 9,140 second-feet Jan. 1, 1934.

Remarks. - Records poor. Flow partially regulated by Tujunga Dam, Pacolma Dam, Halnes 

Debris Basin, Twin Lakes Dams, Chat a worth Reservoir, Tipper and Lower San Fernando 

Reservoirs, Encino Reservoir, and a dam on a tributary of Limekiln Creek. Records 

furnished by Los Angeles County Flood Control District, through H. E. Hedger, chief 

engineer, and by Corps of Engineers, TJ. S. Army.

Mean dally discharge, In second-feet, 1938

February 27 

February 28 

March 1

42 

589 

1,240

Oage height, in feet, and discharge, in second-feet, at Indicated time, 1998

m

l

2

5

4

5

6

7

8

9

10

11

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec. ft.

February 27

\

1.35

1.40

1.60

2.15

2.60

2.90

3.35

3.45

3.56

3.24

2.94

2.82

2.85

2.75

0

0

.1

.2

6

20

37

85

94

110

149

124

110

95

70

40

32

33

gy

Feet Sec. ft.

February 28

2.66

2.65

3.50

4.55

4.82

5.07

5.46

5.76

5.45

4.86

4.62

4.44

4.83

7.50

8,20

22

22

19

35

79

105

280

320

410

520

700

860

835

925

855

700

545

420

350

300

420

1,180

2,500

3.4SO

Feet Sec. ft.

March 1

8.18

8.06

7.95

7.42

6.60

6.05

5.55

5.20

4.97

4.64

4.26

4.26

4.26

4.86

3,700

3,400

5,500

3,100

2,650

2,400

2,030

1,500

1,070

750

580

480

425

360

280

245

240

240

240

240

Feet Sec.ft.

March 2

4.26

4.35

4.70

5.30

7.95

8.65

9.26

240

260

370

620

1,770

3,050

4,100

5,400

Feet Sec.ft.

March 5

Feet Sec.ft.

March 4

Supplemental record.- Float measurements Mar. 2, 9:30 a.m. 

26,300 sec. -ft.

13,400 sec. -ft.; 3:45 p.m.
844 FLOODS 07 MARCH 1938 IN SOUTHERN CALIFORNIA

Los Angeles River .at Los Angeles, Calif.

.- Water-stage recorder, lat. 34C 04'60", long. 118°13'35", in San Rafael grant, 

iieroa Street Bridge (formerly Dayton AvenueT, Los Angeles, Los Angeles County, 

lie upstream fromB Arroyo Seoo. Altitude, 298 feet.

Drainage area.- 510 square miles.

Qaga-halght record.- Water-stage recorder graph for most of period.

Discharge record.- Computed on basis of ourrent-meter measurements and area and velocity 

studies; 140 ourrent-meter measurements, ranging up to 22,000 seoond-feet, were made 

during period Feb. 1 to Apr. 3d, of which 44 were made during period Feb. 27 to liar. 

4. Peak discharge determined by slope-area method.

.- 19381 Discharge, 67,000 seoond-feet 10 p.m. Mar. 2. 

"929-371 Discharge, 22,000 seoond-feet Jan. 1, 1934.

Remarks.- Records fair. Regulation by Twin Lakes Dams, Ohatsworth Reservoir, Upper and 

Lower San Fernando Reservoirs, Snoino Reservoir,- Paooima Dam, and Tujunga Dam. Records except peak discharge furnished by Los Angeles County Flood Control District, 

through H. S. Eedger, chief engineer.

Mean daily discharge, in seoond-feet, 1958

Day

1

Z

3

4

5

6

7

8

9

10

Feb.

598

111

260

242

92

61

45

43

271

110

Mar.

2,300

27,900

8,210

1,790

930

650

600

900

800

770

Apr.

66

65

64

62

61

60

68

57

56

55

Day

11

12

13

14

15

16

17

18

19

20

Feb.

766

188

84

65

55

48

44

45

95

55

Mar.

800

1,320

1,190

800

540

360

340

370

350

350

Apr.

54

53

62

51

49

47

45

48

41

39

Day

21

22

23

24

26

26

27

28

29

30

31

Feb.

42

41

40

43

38

40

252

1,390

184

10,240

Har.

340

340

330

330

180

90

80

74

68

68

67

1,720

108,600

Apr.

38

37

37

37

37

37

37

36

36

50

48.7

2,890

Discharge, in seoond-feet, at indicated time, 1938

Hour

1

2

3

4

6

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

0

0

0

0

0

0

0

0

340

510

621

724

673

548

400

312

265

220

190

170

150

140

130

120

Feb. 28

115

880

330

580

1,000

1,800

2,500

1,390

1,680

1,880

1,440

1,160

1,100

1,120

1,170

1,090

900

850

800

680

1,070

3,120

4,050

6,600

Mar. 1

8,180

5,800

4,400

4,700

4,390

4,810

3,220

2,680

2,230

1,690

1,210

1,010

880

790

690

630

590

540

490

495

490

510

560

890

Mar. 2

1.140

1,100

2,000

3,500

6,200

8,100

10,900

15,600

19,100

25,000

17,700

14,900

22,800

30,600

36,000

44,800

46,500

67,000

36,000

Mar. 3

29,000

23,000

18,000

14,000

11,200

8,800

7,000

5,460

5,670

5,120

4,820

4,640

4,640

4,700

4,640

4,150

3,800

3,400

3,310

3,510

3,130

2,960

2,860

2,790

Mar. 4

2,700

2,540

2,600

2,500

2,320

2,130

1,860

1,750

1,810

1,800

1,810

1,650

1,560

1,450

1,430

1,550

1,420

1,330

1,380

1,370

1,400

1,360

1,300

1,230
L03 ANGELES RIVER BASIN 245

Los Angeles River near Downey, Calif.

Location.- Water-stage recorder, lat. 33°56'45", long. 118°10'25", in San Antonio 

grant, at Stewart and Gray Road Bridge, half a mile above Junction with Rio Hondo, 

and 8y miles west of Downey, Los Angeles County. Staff gages for slop« reading* 

500 feet upstream and downstream. After Mar. 4, gage moved 0.4 of a mile upstream 

to Firestone Boulevard Bridge. Altitude, about 100 feet at new site.

Drainage area.- 614 square miles.

Page-height record.- Water-stage recorder graph Feb. 1-16 and Apr. 11-30. Frequent 

staff gage readings during storm period Feb. 28 to Mar. 4. After 9 p.m. Bar. 2, 

readings taken at upstream slope gage.

Discharge record.- Stage discharge relation at Stewart and Gray Road defined by currentmeter measurements below 19,700 second-feet; extended to peak discharge on basis of 

slope-area determinations. Discharge Mar. 3-4 based on Manning formula and a cross 

section taken after flood. Occasional measurements during periods Feb. 15-87 and 

Mar. 5 to Apr. 11. Stage discharge relation at Firestone Boulevard defined by current-meter measurements below 988 second-feet.

Maxima.- 1938: Discharge, 79,700 second-feet 10 p.m. Mar. 2. 

1928-37: Discharge, 29,400 second-feet Jan. 1, 1934.

Remarks.- Records fair. Regulation at Pacoima Creek flood-control dam, Tujunga Creek 

flood-control dam, andDevils Gate dam on Arroyo Seco. Records except peak discharge furnished by Los Angeles County Flood Control District, through H. E. Hedger, 

chief engineer.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

1,580

200

525

418

130

80

78

71

518

140

Mar.

4,910

40,000

15,500

2,500

1,600

1,300

1,000

1,500

1,200

1,050

Apr.

82

75

70

64

59

54

50

44

39

34

Day

11

12

13

14

15

16

17

18

19

20

Feb.

1,300

330

235

180

115

68

56

60

110

80

Mar.

1,000

1,500

1,100

840

680

560

520

560

550

540

Apr.

30

27

26

39

29

31

27

26

22

34

Day

21

88

23

84

25

26

87

28

29

30

31

Feb.

55

42

39

37

39

41

400

2,750

20,170

Mar.

530

520

510

500

850

130

125

120

108

96

88

2,625

161,400

Apr.

29

28

21

26

39

52

52

42

48

81

AQ <*

8,580

Discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

February 28

320

540

670

800

1,400

2,600

3,700

5,400

7,300

5,100

4,000

2,900

2,200

1,530

1,300

1,330

1,330

1,200

1,040

940

2,900

5,000

7,300

10,000

March 1

16,700

18,500

12,000

8,300

7,100

6,300

7,100

6,000

4,600

3,700

3,2,00

2,750

2,200

1,750

1,720

1,600

1,450

1,400

1,320

1,230

1,160

1,080

1,000

1,300

March 2

2,400

2,900

2,800

4,500

10,300

16,300

20,700

25,000

35,000

37,000

38,000

36,500

35,000

40,000
246 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Los Angeles River at Long Peach, Calif.

Location.- Water-stage recorder, lat. 33°47'25", long. 118°12'20", in Los Oerritos 

grant, at State Street Bridge at Long Beach, Los Angeles County.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation poorly defined; shifting-control method used 

throughout period. Discharge Mar. 2-11 determined by comparison with adjacent 

stations.

Maxima.- 1938: Discharge, 99,000 second-feet Mar. 2.

1928-37: Discharge, 20,500 second-feet Feb. 14, 1937.

Remarks.- See Los Angeles River at Los Angeles for regulation. Record furnished by 

Los Angeles County Flood Control District, through H. E. Eedger, chief engineer.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

1,960

262

690

815

233

60

32

24

1,370

450

Mar.

7,090

50,000

30,000

8,000

5,400

3,900

3,800

4,400

4,800

4,100

Apr.

831

1,400

1,500

1,650

2,290

2,460

2,580

2,690

2,600

2,060

Day

11

12

13

14

15

16

17

18

19

20

Feb.

1,720

873

160

107

75

63

58

58

81

50

~

Mar.

2,300

2,630

2,880

2,370

2,150

1,900

1,420

1,420

1,630

1,130

Apr.

1,730

1,360

784

310

266

288

255

233

222

200

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

45

41

37

32

22

26

1,140

3,250

491

27,280

Mar.

1,060

986

914

1,140

1,190

1,210

1,130

1,130

1,080

1,050

980

4

QAO

303,800

Apr.

190

352

450

510

465

422

366

324

288

244

58,160

Browns Creek at Chatsworth, Calif.

Location. - Water-stage recorder, lat. 34°15 I 25", long. 118°35'45", in Ex Mission San 

Fernando grant, at Devonshire Street Bridge at Chatsworth, LQS Angeles County. 

Altitude, about 1,100 feet.

Drainage area.- 14.3 square miles.

Page-height record.- Water-stage recorder graph except Mar. 4-11.

Discharge record.- Stage discharge relation defined by current-meter measurements below 296 second-feet; extended by computations based on cross section at gage and 

mean depth-mean velocity relation. Discharge for period of missing gage-height 

record determined by discharge measurements and comparison with adjacent stations.

Maximum.- 1938: Discharge, 870 second-feet 10 a.m. Mar. 2 (gage height, 2.83 feet).

Remarks. - Records poor. Flow slightly regulated by Twin Lakes Dams. No diversions. 

Records, except for the period Mar. 1-3, furnished by Los Angeles County Flood Control District through H. E. Hedger, chief engineer.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

53

512

198

70

18

8

3.0

1.7

1.1

.8

Apr.

1.2-

1.1

1.0

.9

.8

.7

.6

.6

0

0

Day

11

12

13

14

15

16

17

18

19

20

Mean monthly discharge, in second

Feb.

17

.8

0

0

0

0

0

0

0

0

Mar.

1.7

26

7

8

7

6

3.0

2.5

2.4

2.3

Apr.

0

0

0

0

0

0

0

0

0

0

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

0

9

0.96 

53

Mar.

2.2

2.1

2.0

1.9

1.8

1,8

1.7

1.6

1.5

1.4

1,3

30.7 

1,890

Apr.

0

0

0

0

0

0

0

0

0

.4

0.24 

14
LOS ANGELES RIVER BASIN 247

gage height, In feet, and discharge, In second-feet, at Indicated time, 1936

«

1

2

S

4

5

6

7

8

9

10

11

N

1

2

S

4

5

6

7

8

9

10

11

M

Feet Sec. ft.

February 27

0.03

0

1.4

Feet Sec. ft.

February 28

0.06

.12

.14

.62

3.0

9

5.8

8

95

Feet Sec. ft.

March 1

0.29

.28

.23

.21

.21

53

49

38

30

27

Feet Sec.ft.

March 2

0.48

.82

2.62

2.83

2.45

2.81

2.17

2.44

1.95

1.60

1.30

1.08

77

170

794

870

719

859

817

712

529

402

296

225

Feet Sec.ft.

March 3

0.97

.93

1.04

1.04

.92

.87

.73

191

179

212

212

176

161

120

Feet Sec.ft.

March 4

Pacoima Creek near San Fernando, Calif.

Location.- Water-stage recorder, lat. 34°20'02", long. IIS^S'SS", In SE^NEi sec. 24, 

T. 3 H., R. 15' W. , 600 feet upstream from mouth of canyon, 0.2 mile below Pacoima 

flood -control dam, and 4 miles northeast of San Fernando.

Drainage area.- 27.9 square miles.

Remarks.- For records of discharge see Pacoima Creek at flood-control reservoir near 

San Fernando, outflow records.

Pacoima Creek at Mission Acres, Calif.

Location.- Water-stage recorder, lat. 34°13'40", long. 118°27'30n , in Ex Mission San 

Fernando grant, at Parthenla Street Bridge in Mission Acres, Los Angeles County, 3 

miles northwest of Van Nuys. Altitude, about 820 feet.

Drainage area.- 50.6 square miles.

Page-height record.- Water-stage recorder graph Feb. 1 to 3:40 a.m. Mar. 3; occasional 

staff-gage readings thereafter.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 1,270 second-feet; extended logarithmically to peak stage. After 3*40 a.m. 

Mar. 3 discharge estimated from outflow at Pacoima Dam and several current-meter 

measurements.

Maxima.- 1938: Discharge, 2,270 second-feet 3:40 a.m. Mar. 3. 

1929-37: Discharge, 477 second-feet Feb. 8, 1932.

Remarks.- Records poor. Flow partially regulated by Pacoima Dam. Small diversions 

'near mouth of canyon. Records, except peak discharge, furnished by Los Angeles 

County Flood Oontrol District, through H. E. Hedger, chief engineer.

Mean dally discharge, in second-feet. 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

' 6.5

0

5.5

.4

0

0

0

0

1.3

0

Mar.

34

470

Apr. Day

11

12

13

14

15

16

17

18

19

20

Feb.

12

0

0

3.7

1.5

0

0

0

0

0

Mar. Apr. Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

.6

26

114

Mar. Apr.

454720 0-42-17
248 FLOODS OF MARCH 1936 IN SOUTHERN CALIFORNIA

Page height, In feet, and discharge, In seoond-feet, at Indicated time, 19SS

1

1

2

3

4

5

6

7

B

9

1011

N

1

2

3

4

S

6

7

e

9

10

11M

Feet | Seo.ft.

February 27

2.63

2.63

2.80

2.60

2.94

2.96

2.87

2.80

2.77

2.73

2.68

0

0

0

0

0

0

0

0

0

0

.1

.1

6

5.5

.6

.1

0

0

0

0

0

0

0

0

Feet Seo.ft.

February 26

2.77

2.9S

2.93

3.04

3.03

3.10

3.20

3.25

3.20

3.13

3.05

2.98

2.92

2.88

2.85

2.95

3.00

3.44

3.55,

3.9(7

0

0

0

0

0

e

4

14

13

22

37

47

37

28

15

6

3 .

1

.5

5

10

69 lie

240

Feet 300. ft.

March 1

4.00

3.60

3.35

3.25

3.10

3.03

2.97

2.94

2.92

2.69

2.67

2.66

2.66

3.50

300

170

50

30

20

12

7

5

3

1

1

.5

/

0

5

76

Feet | Seo.ft.

Maroh 2

3.53

3.51

3.49

3.64

3.85

3.95

3.85

3.55

3.75

3.90

4.10

4.06

4.03

4.25

4.45

4.60

4.72

4.40

4.56

4.75

5.20

5.60

5.75

6.22

100

95

90

90

160

225

210

170

150

200

405

375

345

310

470

560

650

430

520

630

1,000

1,350

1,660

1.950

Feet | Seo.ft.

March 3

6.24

6.20

6.20

1,970

1,910

1,910

Feet | Sec. ft.

March 4

Supplemental record.- Mar. 3, 3t40 a.m., 2,270 seo.-ft.

Tujunga Oreek near Oolby Ranoh, Oallf.

Location.- Water-stage recorder, lat. 34e 16*10n , long. 116e 09*35n , 25 feet upstream 

from crossing of Idison Road, 300 feet downstream from Lucas Oreek, 3f miles west 

of Oolby Ranoh, Los Angeles County, and 4 miles upstream from Tujunga flood-oontrol 

dam No. 1. Altitude, 2,450 feet.

Drainage yea.- Area, 66.9 square miles. Average altitude, 4,510 fest. Maximum altltuae, 7,078 feet. Average slope, 40 percent. Length of main stream channel, 13.5 

miles. Average slope of main stream channel, 6.6 percent.

Page-height record.- Water-stage recorder graph except for Feb. 14-21 and Mar. 1-29.

Discharge record.- Stage-discharge relation fairly well defined. Discharge Feb. 

14-81 and Mar. 1-29 determined by comparison with adjacent stations.

Maxima.- 19361 Discharge not determined) occurred Mar. 2. 

1930-371 Discharge, 3,910 second-feet Feb. 8, 1932.

Remarks.- No regulation or diversion. Record furnished by Los Angeles County Flood 

Control District, through H. S. Hedger, ohlef engineer.

Mean daily discharge, In seoond-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

46

18

67

110

44

26

22

20

44

74

Mar.

870

8,200

1,600

690

450

330

255

205

175

150

Apr.

83

81

SO

77

72

66

66

65

65

65

Day

11

12

13

14

15

16

17

18

19

20

Feb.

517

20S

69

67

59

50

43

37

32

30

Mar.

130

580

390

285

240

210

195

180

165

150

Apr.

63

65

65

60

56

52

51

49

47

46

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

26

24

22

20

20

19

87

420

60.1

4,450

Mar.

. 140

130

125

120

115

110

106

102

98

66

84

636

33,060

Apr.

44

42

42

43

44

42

41

40

42

41

56.6

3,370
LOS ANOKLES RIVER BASIN 249

Tujunga Creek near Sunland, Calif.

Location.- Water-stage recorder, lat. 34°17 '55", long. 118e 16'10n , near center of eec. 

32, T. 3 N., R. 13 W. (unsurveyed), a quarter of a mile downstream from a partly 

constructed and abandoned dam, 2 miles upstream from mouth of oanyon, and 4 miles 

northeast of Sunland. Altitude, 1,600 feet.

Drainage area.- Area, 106 square miles. Average altitude, 4,220 feet. Maximum altitude, 7,078 feet. Average slope, 40 percent. Length of main stream channel, 21.5

miles. Average slope of main stream channel, 3.9 percent.

Sage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation fairly well defined below 1,7CO second-feet. 

Discharge Feb. 15, 16, Mar. 2, 3, 8-12, 14-30, and Apr. 8-20, obtained by comparison 

with record at flood-control dam.

Maxima.- 19381 Discharge 50,000 second-feet Mar. 2.

1916-37: Discharge, 8,500 second-feet Dec. 19, 1921.

Remarks.- Flow partly regulated by flood-control reservoir 5.4 miles upstream. Record 

TunTished by Los Angeles County Flood Control District, through H. E. Hedger, chief 

engineer.

Mean daily discharge,- in seoond-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

1 Feb.

38

22

98

79

62

50

46

42

38

24

Mar.

763

13,000

3,700

1,280

841

910

1,220

886

692

445

Apr.

159

157

154

150

168

190

186

140

105

105

Day

11

12

13

14

15

16

17

18

19

20

Feb.

206

147

96

86

94

48

62

59

46

69

Mar.

280

600

643

475

440

520

510

380

340

300

Apr.

105

105

105

105

90

49

48

38

31

27

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

68

66

67

68

64

62

50

206

73.7

4,090

Mar.

300

260

230

240

130

230

230

200

160

160

164

985

60,540

Apr.

27

26

24

28

30

24

22

21

23

40

82.7

4,920

Tujunga Creek near San Fernando, Calif.

Location.- Water-stage recorder, lat. 34°15 I 50H , long. 118°22'50", in Ex Mission San 

Fernando grant, at Stonehurst Avenue Bridge, about 3 miles southeast of San Fernando, Los Angeles County. Altitude, about 995 feet.

Drainage area.- 148 square miles.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

1,360 second-feet; extended to peak discharge on basis of a slope-area measurement of

the peak.

Maxima.- 1931-36: 1938: Discharge, 51,000 second-feet about 6 p.m. Mar. 2. 

Dlecharge, 3,750 eecond-feet (estimated) Jan. 1, 1934.

Remarks.- Records poor. Flow partially regulated by Tujunga Dam and by Halnes Debrisebi 

Basin. Reoorda furnished by Los Angeles County Flood Control District, through 

H. E. Hedger, chief engineer, and by Corps of Engineers, U. S. Army.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

1Q

Feb.

41

24

129

108

69

49

44

47

47

36

liar.

1,120

Apr. Day

11

12

13

14

15

16

17

18

19

20

Feb.

234

178

132

110

81

38

61

61

47

61

liar. Apr. Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

61

61

61

66

59

56

56

211

I7Q £

4,420

liar. Apr.
250 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Gage height, In feet, and discharge, In second-feet, at Indicated time, 1958

w

1

2

S

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec.ft.

February 27

Feet Sec.ft.

February 28

2.95

2.87

2.82

2.84

2.94

2.94

3.07

3.20

3.33

3.38

3.48

3.55

3.70

3.78

3.78

3.72

3.63

3.55

3.60

3.80

3.82

3.88

4.30

4.47

27

20

18

19

26

26

39

56

88

100

140

160

260

300

300

265

220

160

200

310

320

390

1,000

1.500

Feet Sec.ft.

March 1

5.20

5.20

4.40

3.95

3.77

3.62

3.56

3.50

3.44

3.35

3.35

3.38

3.29

3.26

3.26

3.28

3.30

3.31

3.31

3.32

3.33

..3.45

3.68

3.61

4,000

4,000

2,000

1,350

1,100

960

860

820

780

700

700

720

640

600

600

620

660

670

670

680

690

780

980

920

Feet Sec.ft.

March 2

3.68

3.70

3.72

3.78

3.88

3.96

3.95

4.25

4.62

5.00

5.50

5. 65-

5.65

8.20

9.10

9.15

8.50

980

1,000

1,050

1,120

1,220

1,360

1,350

1,750

2,600

3,400

4,900

5,600

5,600

20,400

27,500

27,700

22,500

Feet Sec.ft.

March 3

Feet Sec.ft.

March 4

Little Tujunga Creek near San Fernando, Calif.

Location.- Water-stage recorder, lat. 34°16'30n , long. 118°22'20n , In Tujunga grant, 

at Foothill Boulevard Bridge, 4 miles east of San Fernando, Los Angeles County. 

Altitude, 1,250 feet.

Drainage area.- Area, 21.0 square miles. Average altitude, 2,500 feet. Maximum altltude, 5,215 feet. Average slope, 38 percent. Length of main stream channel, 8.0 

miles. Average slope of main stream channel, 9.3 percent.

Gage-height record.- Water-stage recorder graph except Mar. 2 to Apr. 12.

Discharge record.- Stage-discharge relation fairly well defined. Discharge, Mar. 2 to 

Apr. 12, computed by comparison with adjacent stations; discharge, Apr. 12-30, obtained by Interpolation between discharge measurements.

Maxima.- 1938: Discharge, 8,500 second-feet Mar. 2.

1928-37: Discharge, 1,360 second-feet Jan. 1, 1934.

Remarks.- Records furnished by Los Angeles County Flood Control District, through H. £. 

Hedger, chief engineer.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

7

1.5

36

22

5.5

3.2

1.3

1.1

3.5

4.3

Mar.

209

1,300

750

275

123

93

76

62

51

45

Apr.

8.5

8

7.5

7

6.5

6.5

6.5

6.5

6.5

6.5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

71

28

15

9

7.5

6

4.1

4.6

3.8

1.7

Mar.

41

95

139

108

84

71

61

52

45

39

Apr.

6.5

6.5

6.5

6

6

6

6

6

6

5.5

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

1.4

1.3

1.1

1.0

1.0

.8

4.4

64

11.1

617

Mar.

34

29

25

22

19

16

14

12

11

9.5

9

126

7,770

Apr.

5.5

5.5

5.5

5.5

5.5

5

5

5

4.6

4.2

6.08

362
LOS ANGELES RIVER BASIN 251

Halnes Creek near Tujunga, Calif.

Location.- Water-stage recorder and concrete control, lat. 34°15'50", long. 118°16'15" 

In W^SWi sec. 17, T. 2 N., R. 13 W., 800 feet above mouth of canyon, and li miles 

northeast of Tujunga. Altitude, about 2,200 feet.

Drainage area.- Area, 1.2 square miles. Average altitude, 3,322 feet. Maximum altitude, 5,000 feet. Average slope, 71 percent. Length of main stream channel, 2.0 

miles. Average slope of main stream channel, 26 percent.

Qage-height record.- Water-stage recorder graph except Mar. 5, 6, and Apr. 3-7.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 3.2 second-feet; extended to peak stage by weir formula. Discharge Mar. 5, 6, 

Apr. 3-7, estimated.

Maxima.- 1938: Discharge, 265 second-feet 1:30 p.m. liar. 2 (gage height, 4.60 feet). 

1917-34, 1935-37: Stage, 11.0 feet Jan. 1, 1934 (discharge not determined).

Remarks.- Records fair. No diversion or regulation during flood period.

Mean dally discharge, in second-feet, 1938'

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0.3

0

1.4

.1

0

0

0

0

.3

.4

Mar.

8

70

30

12

6.5

4.3

3.4

3.1

2.1

1.6

Apr.

0.9

1.0

1.0

.9

.9

.9

.9

.8

.8

.8

Day

11

12

13

14

15

16

17

18

19

20

Feb.

4.0

.8

.2

0

0

0

0

0

0

0

Mar.

1.6

2.8

3.3

2.4

2.2

2.0

1.9

1.8

1.7

1.6

Apr.

0.8

1.0

1.0

.8

.6

.6

.6

.6

.6

.6

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

.1

5.5

0.47

26

Mar.

1.6

1.5

1.4

1.2

1.2

1.1

1.0

1.0

1.0

1.0

.9

348

Apr.

0.6

.6

.6

.6

.7

.7

.7

.7

.7

.7

45

Qage height. In feet, and discharge, In second-feet, at Indicated time, 1936

ft 1

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet [Sec.ft.

February 27

»

Feet Sec.ft.

February 28

1.20

1.20

1.30

1.79

1.53

1.60

1.62

1.57

1.74

1.70

1.85

1.83

1.77

1.70

1.61

1.59

1.60

1.59

1.59

1.75

2.70

2.35

2.50

2.74

0.1

.1

.4

3.9

1.4

1.9

2.1

1.7

3.2

2.8

4.6

4.3

3.7

2.9

2.0

1.9

1.9

1.9

1.9

3.4

26

14

19

29

Feet Sec.ft.

March 1

16

12

9.5

8

6.5

6

5.5

4.8

4.4

4.0

3.9

3.9

Peet 1 Sec. ft.

March 2

2.20

2.15

2.76

2.97

3.10

3.17

3.40

4.30

4.40

4.40

3.9

3.9

4.0

4.3

6.5

12

11

32

43

52

58

77

202

222

222

135

105

90

80

71

65

59

55

52

Feet Sec.ft.

March 3

47

42

38

34

31

28

26

24

22

20

19

18

Feet | Sec.ft.

March 4

15

14

12

11

10

9

Supplemental records.- Feb. 28, 11:30 p.m., 3.18 feet, 54 sec.-ft. 

m., 3.85 feet, 130 sec.-ft.; 1:30 p.m., 4.60 feet, 265 sec.-ft.

Mar. 2, 11:15
262 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Verdugo Creek at Del Valle Avenue, 0lendsle, Calif.

Location.- Water-stage recorder, lat. 34°ll'05n , long. 118°13'35", in San Rafael grant, 

at Del Valle Avenue, Olendale, Los Angeles County. Altitude, about 915 feet.

Drainage area.- 19.1 square miles.

Page-height record.- Water-stage recorder graph..

Discharge record.- Stage-discharge relation determined by computations of.discharge by 

Mann ing' s e quat i on; the channel is concrete lined and of uniform cross section.

Ima.- 1938i Discharge, 3,500 second-feet 2:12 p.m. liar. 2 (gage height, 2.10 feet). 

935-37s Discharge, 1,020 second-feet Jan. 5, 1935.

Remarks.- Records good. Basic data furnished by Los Angeles County Flood Control Distrlot, through-H. £. Hedger, chief engineer, and by Corps of Engineers, TJ. S. Army.

Mean daily discharge, in second-feet, 1938

February 27 

February 28 

March 1 

March 2

Runoff, in acre-feet

0. 

50 

40 

662

8

1,490

Gage height, in feet, and discharge, in second-feet, at indicated time, 1956

m

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

0

0

0

0

.04

.04

.06

.12

.15

.16

.16

.16

.13

.06

.06

.09

.05

.06

.04

.03

.03

.05

.03

.03

0

0

0

Q

.1

.1

.3

1.7

3.0

3.6

3.6

3.6

2.0

.3

.3

.7

.2

.3

.1

0

0

.2

0

0

Feet Sec. ft.

February 28

0.08

.09

.07

.22

.17

.21

.31

.28

.32

.38

.38

.36

.36

.32

.28

.22

.20

.18

.18

.22

.46

.87

.78

1.01

0.5

.7

.4

8

4.5

7.5

21

16

24

37

37

32

32

24

16

8

6.5

5

5

8

62

330

247

500

Feet | Sec. ft.

March 1

0.73

.62

.53

.47

.41

.38

.33

.30

.27

.85

.22

.19

.18

.17

.16

.15

.15

.15

.15

.16

.16

.16

.18

.27

207

134

90

65

45

37

25

19

15

12

8

5.5

5

4.5

3.6

3.0

3.0

3.0

3.0

3.6

3.6

3.6

5

15

Feet Sec. ft.

March 2

0.36

.28

.31

.58

.67

.68

.78

.84

1.22

1.53

1.07

1.32

1.52

1.90

1.88

1.40

1.18

.97

.85

.82

.73

.68

32

16

21

113

165

171

247

301

895

1,590

590

1,100

1,570

2,720

2,660

1,280

810

446

310

280

205

170

140

120

Feet | Sec. ft.

March 3

Feet | Sec. ft.

March 4

Supplemental record.- Mar. 2, 2:12 p.m., 2.10 ft., 3,500 sec.-ft.
LOS ANOELBS RIVER BASIN 853

Verdugo Greek at Qlendale, Calif.

Location.- Water-stage recorder, lat. 34C 09'25", long. 118°16'25n , In San Rafael grant, 

at Eetelle A vs., Olendale, Los Angeles County, 0.4 mile above junction with Los 

Angeles River. Altitude, about 465 feet.

Drainage area.- 22.4 square miles.

Page-height reoord.- Water-stage recorder graph except 4 p.m. 

gage readings Mar. 3 and 8.

Dls

Mar. 2 to Mar. 9. Staff

Ige record.- Stage-discharge relation defined by current- ster measurements Feb.

and Mar. 14 to Apr. 30. Discharge Feb. 27 to Mar. 2 and Mar. 8-13 computed by

Manning's formula, using coefficients based en current 

second-feet and lees. Discharge estimated Mar. 3-7.

Maxima.- 1938! 1935-37« Discharge, 4,500 second-feet 2t25 p.m. Mar. 

Dleoharge, 1,100 second-feet Mar. 30, 1936.

ster measurements of 110

2 (gage height, 2.9 feet).

Remarks.- Records good except those estimated, which are poor. Channel Is concrete 

lined and of uniform section and slope. Basic data for Feb. 27 to Mar. 13 and 

entire record for Feb. 1-26 and Mar. 14 to Apr. 30 furnished by Los Angeles County 

Flood Control District, through H. E. Hedger, chief engineer.

Mean dally discharge, in second-feet, 193S

Day

1

2

3

4

5

6

7

8

9

10

F9b.

33

3.5

18

31

8.5

3.8

2.5

1.6

23

6.5

Mar.

121

1,250

95

43

25

18

14

16

8

9.5

Apr.

0.4

.4

.4

.4

.4

.4

.4

.4

.4

.4

Day

11

12

13

14

16

16

17

18

19

20

Mean monthly discharge, in second

Feb.

59

13

3.8

1.6

.5

1.2

.5

.5

.6

.4

Mar.

17

38

27

11

9.5

9.5

13

8.5

6.5

4.5

Apr.

0.4

.4

.5

1.5

.8

.8

.6

.4

.4

.5

Day

21

22

23

24

26

26

27

28

29

30

31

Feb.

0.4

.4

.3

.3

.2

.3

12

140

13.1 

727

Mar.

2.0

1.2

1.2

.6

.5.6 '

.6

.8

.6

.6

.4

56.6 

3,480

Apr.

O.S

1.2

1.2

.8

.8

1.2

.8

.6

.5

.8

0.63 

38

Gage height, in feet, and discharge, In eeoondrfeet, at indicated time, 1938

n

1

2

3

4

5

6

7

8

9

10

11

N

1

Z

3

4

5

6

7

8

9

10

11

M

Feet Seo.ft.

February 27

0.06

.06

.15

.20

.19

.15

.15

.20

.35

.40

.46

.44

.38

.30

.30

.30

.31

.30

.29

.20

.17

.16

.16

.18

0.2

.2

2.3

5

4.2

2.3

2.3

5

23

32

46

.. 41

28

15

15

15

16

15

14

5

3

2.5

2.5

3.7

Feet Sec. ft.

February 28

0.18

.33

.32

.40

.39

.40

.71

.58

.65

.61

.62

.61

.57

.53

.47

.39

.35

.34

.33

.35

.65

1.35

1.19

1.48

3.7

19

18

32

30

32

149

86

117

98

103

96

82

68

49

30

23

21

19

23

117

900

650

1,160

Feet Seo.ft.

March 1

1.19

.97

.85

.75

.65

.58

.52

.49

.47

.45

.44

.42

.41

.41

.41

.41

.40

.40

.40

.40

.40

.40

.41

.52

650

385

243

171

117

86

64

55

49

44

41

36

34

34

34

34

32

32

32

32

32

32

34

64

Feet Sec. ft.

March 2

0.53

.52

.54

.87

1.06

1.12

1.36

1.44

1.76

2.37

1.71

1.82

2.14

2.50

2.51

2.05

68

64

71

258

480

515

920

1,080

1,740

3,180

1,640

1,860

2,600

3,500

3,520

2,410

Feet Sec.ft.

March 3

Feet Sec.ft.

March 4

Supplemental record.- Mar. 2, 2.25 p.m., 2.9 ft., 4,500 sec.-ft.
254 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Arroyo Seco near Pasadena, Calif.

Location.- Water-stage recorder and concrete control, lat. 34°13'2011 , long. 118°10' 

40", near north line of sec. 31, T. 2 N., R. 12 W., 1& miles above mouth of Millard 

Canyon, and 5& miles northwest of Pasadena. Altitude, about 1,400 feet.

Drainage area.- Area, 16.4 square miles. Average altitude, 3,692 feat. Maximum altltude, 6,152 feet. Average slope, 46 percent. Length of main stream channel, 6.6 

miles. Average slope of main stream channel, 14 percent.

Page-height record.- Water-stage recorder graph except 10 a.m. Mar. 2 to Mar. 28.

Discharge record.- Stage-discharge relation fairly well defined by current-meter 

measurements below 300 second-feet; peak discharge obtained by slope-area method. 

Discharge for tiie maximum 24 hours obtained from rainfall-runoff studies, and for 

the remainder of the period Mar. 2-28 by comparison with the inflow into Devils 

Gate flood-control reservoir, li miles downstream.

Maxima.- 1938: Discharge, 8,620 second-feet About 4 p.m. Mar. 2. 

1910-37: Discharge, about 5,630 second-feet Feb. 20, 1914.

Remarks.- Records fair. No diversions or regulation above gage. 

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

21

8.5

164

118

49

28

19

15

37

42

Mar.

565

2,700

808

261

208

178

158

143

125

112

Apr.

50

46

42

40

38

36

35

32

31

30

Day

11

12

13

14

15

16

17

18

19

20

Feb.

232

81

50

38

34

21

17

16

16

14

Mar.

108

158

152

147

135

125

117

109

102

94

Apr.

30

29

26

26

25

25

25

25

25

24

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

12

11

10

10

9.5

9.5

20

351

2,880

Mar.

87

80

73

72

71

70

69

68

64

58

54

14,420

Apr.

24

24

24

24

24

23

23

23

25

25

1,740

Discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feb. 27

9

9

9

9

10

10

10

11

14

19

24

26

27

30

32

32

33

37

36

35

33 ,.

32

31

30

Feb. 28

30

30

30

30

62

74

155

160

200

255

340

450

480

450

410

390

340

320

240

200

250

600

1,230

1,850

Mar. 1

2,000

1,400

1,080

940

820

740

680

620

554

490

440

390

335

300

255

230

215

195

178

170

165

162

165

210

Mar. 2

225

220

200

280

390

510

770

940

1,050

1,500
LOS ANQELES RIVER BASIN 255 

Santa Anita Creek near Sierra Madre, Calif.

Location.- Water-stage recorder, lat. 34*11'45", long. 118°01'05", In SW^SEi sec. 3 

(revised), T. IK., R. 11 W., at head of Hermits Palls, 4 miles northeast of Sierra 

Madre. Altitude, about 1,400 feet.

Drainage area.- Area, 10.5 square miles. Average altitude, 3,560 feet. Maximum altitude, 5,886 feet. Average slope, 47 percent. Length of main stream channel, 4.0 

miles. Average slope of main stream channel, 20 percent.

Sage-heIght record.- Water-stage recorder graph Mar. 18 to Apr. 30. Station was destroyed Mar. 2 Including the gage-height record for the period Feb. 1 to Mar. 2; 

station reestablished Mar. 18.

Discharge record.- Discharge Feb. 1 to Mar. 17 determined by comparison with Inflow into flood-control reservoir about half a mile below station. Stage-discharge relation 

fairly well defined Mar. 18 to Apr. 30.

Maxima.- 1938: Discharge, about 5,200 second-feet Mar. 2.

1916-37* Discharge, about 3,300 second-feet Apr. 7, 1926.

Remarks.- Records fair. No regulation or diversion above station.

Mean dally discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

17

8

43

63

31

19

14

12

21

24

Mar.

433

1,580

511

230

162

130

107

90

79

72

Apr.

36

34

33

33

33

30

28

26

25

25

Day

11

12

13

14

15

16

17

18

19

20

Feb.

60

60

42

28

25

19

17

16

14

12

Mar.

68

138

122

105

94

88

84

82

79

73

Apr.

25

27

27

25

24

23

22

21

20

 22

Day

21

22

23

24

25

26

27

28

29

30

31

Runoff, In acre-feet .........................................

Feb.

10

9

8.5

8

7.5

7

17

334

1,860

Mar.

67

62

57

54

52

48

45

44

42

40

37

157

9,670

Apr.

22

21

20

24

22

20

19

19

20

22

OA Q

1,480

Littie Santa Anita Creek near Sierra Madre, Calif.

Location.- Water-stage recorder, lat. 340 11 I 15", long. 118°02'35", near center of NW£ 

sec. 9, T. ^ H., R-. 11 W., 2 miles northeast of Sierra Madre. Altitude, about 2,200 

feet.

Drainage area.- Area, 1.9 square miles. Average altitude, 3,430 feet. Maximum altltude, 5,433 feet. Average slope, 50 percent. Length of main stream channel, 2.0 

miles. Average slope of main stream channel, 31 percent.

Sage-height record.- Water-stage recorder graph except Mar. 1-18.

Discharge record.- Stage-discharge relation fairly well defined below 60 second-feet. 

Discharge Mar. 1-18 obtained from records of inflow into flood-control reservoir 

about 1 mile below station.

Maxima.- 1938: 1916-37: Discharge, 536 second-feet Mar. 2.

Stage, 11.75 feet Apr. 7, 1926 (discharge not determined).

Remarks.- Records fair. No regulation or diversion above gage.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

1.7

1.1

5.5

8

3.6

2.6

2.0

1.6

2.2

2.6

Mar.

57

182

100

41

33

26

23

14

16

14

Apr.

10

10

10

10

10

7.5

6

6

6

6

Day

11

12

13

14

15

16

17

18

19

20

Feb.

5.5

6.5

7.5

4.0

3.3

3.1

2.7

2.5

2.4

2.0 '

Mar.

16

32

30

16

25

18

16

14

13

12

Apr.

6

6

6

5.5

4.9

4.7

4.2

3.9

3.6

3.4

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

1.6

1.5

1.4

1.3

1.3

1.2

2.0

42

243

Mar.

12

12

11

10

10

10

10

10

10

10

10

1,610

Apr.

3.3

3.3

3.0

3.0

2.7

2.7

2.6

2.6

2.6

2.6

5 07

314
856 FLOODS OF MAROH 1936 IN SOUTHERN CALIFORNIA 

Baton Greek near Pasadena, Oallf.

Location.- Water-atage recorder, lat. 34°11'40", long. 116°06"15", In SBfc sec. 8, T. 1 

H., R. IS W., at mouth of canyon, just upstream from Mount Wilson toll bridge site, 

and 4 miles northeast of Pasadena. Altitude, 1,830 feet.

Drainage, area.- Area, 6.5 square miles. Average altitude, 3,830 feet. Maximum altl- 

"tude, 6,156 feet. Average slope, 61 percent. Length of main stream channel, 4.0 

miles. Average slope of main stream channel, 83 percent.

Page-height Iht_____ record.- Water-stage recorder graph except Feb. 16 to Mar. 89; staff gage

read twice dally Mar. 21-29. Station destroyed Mar. 2 with loss of gage-height 

record for Feb. 16 to Mar. 8; station reestablished Mar. 81.

Discharge record.- Stage-discharge relation fairly mil defined below 100 second-feet, 

Discharge Feb. 16 to Mar. 89 obtained by comparison with the Inflow Into floodcontrol reservoir about 8 miles downstream.

Maxima.- 1936s 

' ,918!-37t

Discharge, 3,400 second-feet 5 p.m. Mar. Z. 

Discharge, about 1,360 second-feet Apr. 7, 1986.

'Ics.- Records good except those for Feb. 16 to Mar. 29, which are poor. Diversions 

above gage by Olty of Pasadena not Inoludsd In dally and monthly records.

Mean dally discharge, In second-feet, 1938

Day

1

8

3

4

5

6

7

8

9

10

Feb.

9

1.9

36

46

80

4.6

0

0

9

6.5

Mar.

148

836

868

111

82

70

63

58

50

37

Apr.

18

13

9

11

18

11

11

10

8

8.5

Day

11

12

13

14

15

16

17

16

19

80

Feb.

45

40

20

11

7.5 ' 6

18

5

5

3

Mar.

43

66

«6

60

51

45

40

35

39

35

Apr.

9

14

18

10

6.5

6

7

6

6

7.5

Day

81

82

83

84

85

86

87

86

89

30

31

Feb.

8

8

8

8

8

80

80

144

17.8

ORK

154

Mar.

38

86

86

84

83

84

84

83

88

16

17

79.0 

4,660

6

Apr.

6

7

6

5.5

5

4.5

4.6

4.5

3.6

4.5

8.48 

501

857
LOS ANQELES RIVER BASIN 257

Eaton Creek near El Monte, Calif.

Location.- Water-stage recorder, lat. 34°05'15", long. 118°03'55", in San Francisquito 

grant, at Sunset Avenue Bridge, near El Monte, Los Angsles County. Altitude, about 

288 feet.

Drainage area.- 18.4 squars miles.

Page-height record.- Water-stage rscorder graph and staff-gage readings.

Discharge record.- Defined by current-meter measurements .below 400 second-feet; extended, 

to peak discharge determined by slope-area method.

Maxima.- 1938: Discharge, about 2,300 second-feet 6 p.m. Mar. 2 (gage height, 9.0 

feet).

1930-37: Discharge, 2,180 second-feet Jan. 1, 1934.

Remarks.- Record poor. Partial regulation at Eatv>n Creek flood-control dam. The Pasadena Water Department diverts water just abovs Eaten Wash debris dam. Records 

except for the period Feb. 28 to Mar. 2 furnished by Los Angeles County Flood Control District, through E. E. Hedger, chief engineer.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

38

0

29

4.5

0

0

0

0

30

0

Mar.

200

770

251

138

92

100

62

23

34

44

Apr. Day

11

12

13

14

15

16

17

18

19

20

Feb.

18

3.5

0

0

0

0

0

1.1

2.6

0

Mar.

0

13

14

0

7.5

16

8

9.5

11

5

Apr. Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

18

107

8 QQ

499

Mar.

0

0

0

0

0

0

0

0

6

.8

0

CQ n

3,580

Apr.

\

0

0

gage height, In feet, and discharge, In second-feet, at Indicated time, 1938

w

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec. ft.

February 27

2.79

2.79

3.08

3.09

3.30

3.48

3.45

4.15

4.34

4.10

3.90

3.92

3.78

3.74

3.58

3.50

3.30

3.40

3.57

3.40

3.29

0

0

.6

.6

3.0

10

4.6

112

145

73

30

29

9

4.6

.2

0

0

0

.1

0

0

Feet Sec.ft.

February 28

3.31

3.65

3.91

4.02

4.35

4.30

4.02

5.93

5.07

4.90

4.35

4.25

4.12

4.26

5.42

5.35

5.67

0

.8

19

29

104

64

12

582

255

190

48

34

17

5

5

64

436

418

501

Feet Sec.ft.

March 1

5.31

5.25

5.30

5.32

5.32

5.35

5.35-

5.32

5.15

5.08

5.06

5.20

5.33

5.33

339

303

293

270

248

222

190

148

110

97

87

120

154

151

Feet Sec.ft.

March 2

5.50

5.45

5.48

5.70

6.10

6.30

6.50

6.66

6.75

6.70

6.28

6.21

7.31

7.00

7.70

8.90

6.20

9.00

7.60

6.65

6.61

6.66

6.32

5.58

199

181

187

255

392

463

J535

594

625

598

429

396

862

836

1,240

1,950

750

2,300

1,500

1,030

990

990

823

516

Feet Sec.ft.

March 3

Feet Sec. ft.

March 4
258 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Rubio Canyon Wash at Rosemead, Calif.-

Location.- Water-stage recorder, lat. 340 04'30", long. 118°04'35", In NWi sec. 19, T. 

IS., R. 11 W., at aiendon Way in Rosemead. Altitude, about 290 feet.

Drainage area.- 13.4 square miles.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 1,470 second-feet; extended logarithmically to peak atage.

Maxima.- 1938: Discharge, 2,700 second-feet 9 a.m. Mar. 2 (gage height, 2.55 feet). 

1930-37: Discharge, 2,070 second-feet Dec. 31, 1933.

Remarks.- Records good. Channel is concrete lined and of uniform section. Baae data 

Feb. 27 to Mar. 3 and entire record Feb. 1-26 and Mar. 27 to Apr. 30 furnished by 

Los Angeles County Flood Control District, through H. E. Hedger, chief engineer.

Mean daily discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

107

7.5

54

21

.1

.1

0

2.9

61

2.5

Mar.

101

815

59

10

6.5

2.5

6.5

14

2.1

1.2

Apr.

0.2

.2

.2

.2

.4

.4

.2

.1

.2

.2

Day

11

12

13

14

15

16

17

18

19

20

Feb.

69

9

.4

1.6

.1

0

0

4.1

10

0

Mar.

9

58

18

4.8

4.1

3.3

2.5

2.1

2.1

1.6

Apr.

0.2

1.1

4.8

1.6

.2

.1

.1

0

0

0

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0.8

.4

.2

0

0

0

86

322

07 i

1,510

Mar.

1.2

.8

.8

.4

.4

.4

.4

.4

.4

.2

.2

2,240

Apr.

0

0

0

2.3

4.1

.2

0

0

0

.4

35

Gage height, In feet, and discharge, in second-feet, at indicated time, 1938

I

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

0.04

.06

.32

.30

.26

.20

.27

.65

.70

.80

.70

.65

.52

.35

.26

.23

.18

.18

0.1

.3

60

53

40

25

44

220

252

325

252

220

148

70

40

33

20

20

Feet Sec. ft.

February 28

0.15

.55

.40

.45

.75

.53

1.15

1.31

.97

1.04

.48

.58

.60

.46

.30

.36

.30

1.25

1.71

1.28

1.80

15

163

90

113

285

152

625

796

460

525

127

180

190

117

52

74

52

730

1,300

760

1,420

Feet Sec. ft.

March 1

1.05

.62

.37

.28

.24

.20

.20

.50

535

200

78

50

35

25

25

137

Feet Sec. ft.

March 2

0.75

.50

.68

1.10

1.30

1.20

1.72

1.47

2.55

2.20

1.15

1.35

1.45

1.55

2.00

1.81

1.70

1.18

.85

.71

.55

.45

285

136

240

580

780

680

1,310

980

2,700

2,020

625

850

960

1,070

1,720

1,420

1,280

660

360

260

163

113

Feet | Sec. ft.

March 3

0.35

.28

.42

.90

.32

.26

.32

.20

.19

70

46

100

400

5.0

28

50

14

12

Feet Sec. ft.

March 4

0.18 10
LOS ANGELES RIVER BASIN 269

Alhambra Wash at Alhambra, Calif.

Location.- Water-stage recorder, lat. 34°03' 20", long. 118°05"Id", In Potrero Orande 

grant, about 250 feet above Short Street in Alhambra, Los Angeles County. Zero of 

gage is 243.8 feet above mean sea level.

Drainage area.- 14.5 square miles.

Gage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

456 second-feet; extended to peak discharge on basis of a slope-area measurement of 

the peak. Discharge Feb. 27 to Mar. 2, computed by Manning's formula and five 

current-meter measurements made during the period.

Maxima.- 1930-37: 1938: Discharge, 4,100 second-feet 9 a.m. Mar. 2, (gage height, 5.50 feet). 

Discharge, 4,890 second-feet Jan. 1, 1934.

Remarks.- Records fair. No regulation or diversion. Channel is concrete lined and

of uniform section and slope. Records furnished by Los Angeles County Flood Control 

District, through H. E. Hedger, chief engineer, and by Corps of Engineers, XT. S. 

Army. Discharge Feb. 27 to Mar. 2 computed by Corps of Engineers, XT. S. Army.

Mean daily discharge, in second-feet, 1938

Day

1

2

-,3"4

5

6

7

8

9

10

Feb.

177

.8

84

11

0

0

0

0

76

12

Mar.

101

803

30

.2

0

.8

S.I

7

0

0

Apr.

0

0

0

0

0

0

0

0

0

0

Day

11

12

13

14

15

16

17

18

19

20

Feb.

113

7

0

0

0

0

0

.4

4.8

0

Mar.

3.9

75

33

7

1.6

.4

.4

0

0

0

Apr.

0

0

0

0

0

0

0

0

0

0

Day

SI

22

S3

24

25

26

27

28

29

30

31

Runoff, in acre-feet .......................................

Feb.

0

0

0

0

0

0

178

56S

43.8

S,430

Mar.

0

0

0

0

0

0

0

0

0

0

0

S,110

Apr.

0

0

0

0

0

0

0

0

0

0

0

gage height, in feet, and discharge, in second-feet, at indicated time, 1938

h 

t

1

2

3

4

6

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

H

Feet Sec.ft.

February 27

0.40

.50

.58

.96

2.05

S.10

2.43

2.17

0

16

23

70

380

400

560

430

310 

260

285

S25

S03

197

ISO

156

170

Feet Sec.ft.

February 28

80

135

134

156

250

190

800

S.OOO

1,120

940

200

170

145

90

7S

65

59

55

53

52

800

S.300

1,600

3.650

Feet Sec.ft.

March 1

740

185

125

105

85

65

49

37

29

S2

18

15

12

10

9

7.5

7

6

5.5

5

4.7

4.4

4.2

4.8

Feet Sec.ft.

March 2

5.50

4.00

265

130

190

660

1,500

1,200

1,660 *

1,400

4,100

1,600

340

235

610

5SO

1,250

900

1,100

183

60

28

19

17

16

15

Feet Sec.ft.

March 3

14

IS

Feet Sec.ft.

March 4
860 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Rio Hondo near El Monte, Calif.

Location.- Water-stage recorder, lat. 34°05'351', long. 118°0l'55n , In San Franoisqulto 

grant, at Lower Asusa road bridge, li miles north of El Monte, Los Angeles County. 

Altitude, about 295 feet.

Drainage area.- A natural apiIt near Arrow Highway divides the San Gabriel River Into 

two branches. The west branch Is known as the Rio Hondo. The San Gabriel River 

drainage area above the split Is 230 square miles; the Rio Hondo drainage area from 

the split to Lower Azusa road is 54.9 square miles.

Page-height reeord.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

3,860 second-feet} extended logarithmically to peak discharge on basis of a slopearea measurement of the peak.

Maxima.- 1938s Discharge, 31,800 second-feet 9 p.m. Mar. 2 (gage height, 7.56 feet). 

1932-361 Discharge., 5,860 second-feet Jan. 1, 1934.

Remarks.- Records poor. Regulation by Santa Anita, San Gabriel No. 1, San Gabriel No. 

2, and Morris Dams. The City of Pasadena diverts water from the San Gabriel River 

and the City of Monrovia diverts water from Monrovia Creek; there are several diversions, for Irrigation. Records furnished by Los Angeles County Flood Control District, through H. E. Hedger, chief engineer, and by Corps of Engineers, U. S. Army.

Mean daily discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

64

0

76

62

32

13

10

11

36

11

Mar.

1,270

7,700

11,000

2,960

2,800

2,730

4,280

3,660

.4,510

2,200

Apr.

331

837

531

735

909

1,780

1,800

1,780

1,780

1,520

Day

11

12

13

14

15

16

17

18

19

20

Feb.

51

68

48

35

25

24

13

10

7

0

Mar.

1,230

1,550

1,990

1,720

1,390

1,050

780

1,200

1,460

1,120

Apr.

1,120

305

225

222

229

245

284

260

210

199

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

1.4

9

83

81

79

415

45.2

2,510

Mar.

596

290

773

1,010

986

986

996

986

986

986

674

8 1 9

'130,60

Apr.

225

241

237

222

117

.2

0

0

0

0

544

32,400

gage height, in feet, and discharge, in second-feet, at Indicated time, 1936

W

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet] Sec.ft.

February 27

2.51

2.52

2.54

2.65

2.73

2.53

2.28

2.17

2.16

2.16

2.15

85

88

96

130

170

98

43

30

28

30

28

Feet |Seo.ft.

February 28

2.17

2.29

2.70

3.16

3.45

3.21

3.10

3.07

3.05

3.07

2.98

2.95

3.00

3.40

3.60

3.60

33

50

190

440

900

610

500

460

440

460

380

360

400

860

1,200

1,200

Feet Sec.ft.

March 1

4.21

4.45

4.15

4.00

3.82

3.83

3.81

3.67

3.56

3.47

3.43

3.42

3.35

3.33

3.23

3.38

3,300

3,800

2,700

2,200

1,750

1,700

1,600

1,300

1,050

860

800

740

640

600

480

630

Feet Sec.ft.

March 2

3.28

3.30

3.49

3.67

3.92

4.06

4.06

4.12

4.25

4.20

4.30

4.45

4.72

4.96

5.07

5.38

6.03

6.14

6.02

5.90

7.56

6.94

6.71

6.41

520

526

730

1,000

1,450

1,800

1,800

1,900

2,300

2,100

2,400

3,100

4,000

g,300

6,000

8,100

13 , 600

15,000

14,000

13,000

31,800

24,000

21,500

18.000

Feet Sec.ft.

March 3

6.04

5.44

5.36

5.20

5.94

6.13

6.06

5.84

5.88

5.76

5.69

5.83

5.70

5.75

5.84

5.71

5.42

5.21

4.87

5.02

5.12

5.13

5.03

14,400

9,200

8,500

7,400

13,500

15,500

15,000

13,000

13,500

12,000

11,600

13,000

12,000

12,400

13,000

12,000

9,600

8,000

5,800

6,800

7,500

7,600

6.800

Feet | Seo.ft.

March 4

4.57

4.21

4.10

3.89

3.49

3.48

3.58

4,950

3,440

3,110

2,230

\

1,780

1,980

3,030
LOS AKQILES RIVER BASIN 261

Rio Hondo near Montebello, Calif.

ation.- Water-stage recorder, lat. 34.01'5511 , long. 118e 04'15", In Potrero Qrande 

grant, at Montebello oil field,'about 1,000 feet upstream from Mission Bridge, and 2 

miles northeast of Montebello, Los Angeles Oounty. Altitude, about 200 feet.

Drainage area.- A natural split near Arrow Highway divides the San Gabriel River Into 

two branches; the west branch Is known as the Rio Hondo. The San Gabriel River drainage area above the split Is 230 square miles; the Rio Hondo drainage area from the 

split to this station Is 113 square miles.

0age-height record.- Water-stage recorder graph except Feb. 1, Mar. 3-8, 9-11, 17, 21-

23, S6-29, Apr. 12-15, 28-30.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

8,800 second-feet; extended to peak discharge determined by slope-area method on 

basis of other discharge Information. Discharge estimated for days of missing record.

 1928-371- Maxima.- 1938: Discharge, 28,000 second-feet 11 p.m. Mar. 2 (gage height, 12.83 feet). 

Discharge, 11,800 second-feet Jan. 1, 1934.

Remarks.- Records fair. Flow partially regulated by Sierra Madre, Santa Anita, Sawplt, 

San Qabrlel Ho. 2, and Morris Dams. The Olty of Pasadena diverts water from Eaton 

Greek and from the San Qabrlel River; the Olty of Monrovia diverts water from Monrovia Greek; several diversions for Irrigation. Records furnished by Los Angeles 

Oounty Flood Control District, through H. E. Hedger, chief engineer.

Mean dally discharge, In second-feet, 1938,

Day

1

2

3

4

5

6

7

8

9

10

Feb.

560

72

335

187

66

54

62

76

345

65

Mar.

1,290

9,500

12,600

2,960

2,600

2,800

2,900

3,490

3,640

2,200

Apr.

556

1,120 .

968

1,320

2,040

2,240

1,960

1,760

1,720

2,010

Day

11

12

13

14

15

16

17

18

19

20

Feb.

364

230

163

125

80

63

49

46

60

11

Mar.

1,400

1,820

1,860

1,770

1,790

1,490

915

1,100

1,080

854

Apr.

1,300

325

250

250

269

259

232

172

207

241

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

25

32

34

38

96

110

419

1,520

189

10,490

Mar.

578

255

610

1,010

980

1,000

1,000

1,000

1,060

1,280

808

2 1 fiO

134,100

Apr.

332

300

280

249

122

30

26

28

31

34

fiQQ

40,920

Page height. In feet, and discharge, In second-feet, at Indicated time, 1938

n

l

2

3

4

5

6

7

S

9

10

11

K

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Seo.ft.

February 27

4.89

4.93

5.04

5.06

5.49

5.96

6.10

6.19

5.92

5.66

5.38

5.20

4.80

4.78

4.58

4.50

4.52

4.76

132

150

211

222

532

1,020

1,190

1,320

1,020

820

630

540

306

274

179

152

157

234

Feet Seo.ft.

February 28

4.81

5.35

5.20

6.06

5.65

5.55

7.75

7.57

7.59

6.45

6.15

5.68

5.77

5.50

5.35

5.33

5.15

5.05

5.50

7.45

7.95

8.19

200

200

600

500

1,100

900

700

4,000

3,600

3,800

2,000

1,400

1,200

1,300

1,000

800

700

600

500

500

1,400

3,600

4,100

4,400

Feet Seo.ft.

March 1

8.42

7.55

7.17

6.85

6.58

6.34

6.12

6.00

5.78

5.60

5.48

5.30

5.18

5.14

5.10

5.16

5,000

3,600

2,500

2,000

1,700

1,400

874

759

682

580

520

503

492

538

Feet Seo.ft.

March 2

6.15

5.96

5.85

6.85

7.90

8.45

8.80

9.29

10.13

9.57

8.82

8.07

8.82

8.91

9.94

10.15

10.77

10.65

10.30

10.02

9.97

11.62

12.83

1,300

1,200

1,000

2,500

4,700

6,300

6,700

7,300

10,000

8,500

6,000

4,300

7,000

7,700

12,000

13,000

15,000

16,000

13,000

12,000

12,000

18,000

28,000

24,000

Feet Seo.ft.

March 3

22,000

20,000

18,000

16,000

14,000

11,000

9,000

7,800

12,000

16,000

15,000

14,000

14,000

13,000

13,000

12,000

12,000

11,000

9,800

8,700

7,600

Feet | Sec. ft.

March 4
262 FLOODS OF MARCH 1933 IN SOUTHERN CALIFORNIA 

Rio Hondo near Downey, Calif.

Location.- Water-stage recorder, lat. SS'se^O", long. IIS'CO'SO", In San Antonio grant, 

at Stewart and Sray Road Bridge, half a mile upstream from confluence with Los 

Angeles River, and li miles west of Downey, Los Angeles County. Altitude, about 95 

feet.

Drainage area.- 140 square miles not Including San Sabrlel River above the split which 

forms Rio Hondo (see Rio Hondo near El Monte).

Sage-heIght record.- Water-stage recorder graph except 7 p.m. Mar. 2 to 9 a.m. Mar. 3. 

Maximum stage read on staff gage.

termlned by comparison with adjacent stations.

Maxima.- 1938: Discharge, 24,400 second-feet 1 a.m. Mar. 3 (gage height, 13.5 feet). 

" 1914, 1923-37: Discharge, 20,900 second-feet February 1914.

Remarks.- Records poor. Regulation at San Gabriel No. 1, San Sabrlel No. 2, Morris, 

Sawplt, and Santa Anita Dams, and Eaton Creek Debris Dam. The City of Pasadena 

diverts water from the San Sabrlel River, the City of Monrovia diverts water from 

Monrovia Creek; several diversions for Irrigation. Records furnished by Los 

Angeles County Flood Control District, through H. E. Hedger, chief engineer.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

3

9

10

Feb.

415

0

205

159

9

1.1

0

0

272

40

Mar.

1,870

11,100

12,700

3,690

2,690

2,500

2,520

?,780

3,520

2,§70

Apr.

444

908

800

1,110

1,750

1,930

1,700

1,400

1,340

 1,220

Day

11

12

13

14

15

16

17

18

19

20

Feb.

222

111

9

0

0

0

0

0

0

0

Mar.

1,210

1,630

1,850

2,050

1,820

1,380

788

997

968

707

Apr.

799

291

172

128

136

141

156

166

161

161

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

2.0

3.3

279

1,360

110

6,120

Mar.

544

158

456

824

800

752

728

800

788

812

831

132,600

Apr.

172

205

223

235

14

0

0

0

0

- .1

31,260

Page height, In feet, and discharge, in second-feet, at indicated time, 1938

M

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

H

Feet | Sec. ft.

February 27

6.20

7.05

7.59

7.66

7.45

7.13

6.88

6.65

6.48

6.30

6.25

6.16

6.05

225

695

1,180

1,220

970

675

560

365

290

215

200

173

140

Feet Sec. ft.

February 28

5.96

5.95

6.05

6.30

7.21

7.80

9.40

8.90

8.08

7.25

6.97

6.75

6.60

6.54

6.46

6.46

6.41

6.49

6.89

8.76

9.40

115

113

138

210

700

1,280

4,900

3,800

2,500

1,480

1,260

1,120

1,020

1,000

950

960

940

1,020

1,480

4,800

6.500

Feet Sec.ft.

March 1

10.05

9.55

8.77

8.03

7.65

7.37

7.13

7.01

6.91

6.80

6.70

6.64

6.57

6.53

6.56

6.54

6.41

6.36

6.33

6.39

8,600

7,100

5,000

3,400

2,750

2,300

2,000

1,850

1,750

1,500

1,310

1,180

1,090

1,030

1,040

1,010

870

790

730

730

Feet Sec.ft.

March 2

6.52

6.87

7.48

7.39

8.20

9.80

10.35

10.60

10.85

11.03

10.98

10.35

9.45

10.22

10.40

11.15

11.60

12.05

12.40

820

1,100

1,800

1,650

2,800

6,300

7,900

8,600

9,400

11,000

11,600

10,200

7,900

10,500

11,000

14,000

15,700

17,700

19,000

Feet Sec.ft.

March 3

13.50

9.10

24,400

9,700

Feet | Sec.ft.

March 4
RECORDS OF STAUE AND DISCHARGE AT STREAM-GAGING STATIONS 26

Ballona Creek Baain 

Centinela Creek near Culver City, Calif.

Location.- Water-stage recorder, lat. SS'SS'SS", long. 118023'05", in Aguaje de la 

Centinela grant, 25 feet south of Centinela Boulevard, "betweenCentinela Boulevard 

and Pacific Electric R. R., and 2-fc miles south of Culver City, Los Angeles County. 

Altitude, about 47 feet.

Drainage area.- 5.17 square miles.

Gage-height record.- Water-stage recorder graph Feb. 27 to 5 p.m. Mar. 2; staff gage 

reading at 12 m. Mar. 4.

Dlacharge record.- Stage-discharge relation defined by current-meter measurements below 580 second-feet; extended logarithmically to peak discharge determined by slopearea method.

Maxima.- 1938: Discharge, 1,900 second-feet 5 a.m. Mar. 2 

1932-37: Discharge, 1,590.second-feet Mar. 2, 1935.

height, 7.83 feet).

Remarks.- Records fair. No regulation or diversions. Records furnished by Los 

Angeles County Flood Control District, through H. E. Hedger, chief engineer, and 

by Corps of Engineers, U. S. Army.

Mean daily discharge, in second-feet, 1938

February 28 

March 1

267 

117

Sage height, in feet, and discharge, in second-feet, at indicated time, 1958 iw

1

2

3

4

5

6

7

8

9

10

11

N

1

2

5

4

5

6

7

8

9

1O

11

M

Feet | Sec. ft.

February 27

3.25

5.25

2.86

2.70

2.55

2.40

2.27

2.18

2.09

2.00

8.00

8.00

8.00

125

128

55

34

16

8

6

3

2

1

1

1

1

Feet Sec.ft.

February 23

2.00

2.00

2.00

2.00

2.50

4.50

5.74

5.74

4.25

2.75

2.68

2.61

2.60

2.59

2.58

2.57

2.57

2.56

2.55

3.50

5.10

5.00

6.55

6.17

1

1

1

1

13

480

950

950

395

41

34

21

20

19

18

18

18

17

16

185

695

660

1,285

1,120

Feet | Sec.ft.

March 1

4.50

2.76

2.76

2.76

2.76

2.75

2.75

2.75

2.75

2.74

2.74

2.74

4.00

4.70

3.60

480

41

41

41

41

40

40

40

40

39

39

39

320

550

210

Feet Sec.ft.

March 2

3.75

6.50

7.58

7.52

7.83

7.30

7.15

7.00

6.00

3.90

4.57

4.00

4.50

4.75

5.70

4.75

3.43

250

1,260

1,780

1,730

1,900

1,640

1,570

1,500

1,060

290

505

320

480

565

935

565

163

Feet | Sec. ft.

March 3

Feet Sec.ft.

March. 4

2.92 0

454720 0-42-18
264 FLOODS OF MARCH 1938 IN SOOTHBRN CALIFORNIA

Ballona Creek near Culver City, Calif.

Location.- Water-stage recorder, lat. 33 059'50", long. 118*24 '1C", in La Ballona grant, 

at aawtelle Boulevard Bridge, about li miles south of Culver City, Los Angeles 

County. Altitude, about- 40 feet.

Drainage area.- 112 square miles.

Page-height record.- Water-stags recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 18,000 second-feet j extended logarithmically to peak stage.

Maxima.- 1938s Discharge, 19,000 second-feet 9:40 a.m. Mar. 2 (gage height, 15.25 

Teet).

1928-37: Discharge, 11,300 second-feet Jan. 1, 1934.

Remarks . - Records fair. Records furnished by Los Angeles County Flood Control Distrlot, through H. 2. Hedger, chief engineer, except those for period Feb. 27 to 

Mar. 5, which were furnished by Corps of Engineers, IT. S. Army.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

a

9

10

Feb.

2,050

134

375

264

17

17

17

92

698

88

Mar.

1,21C

7,410

280

ICO

69

59

55

84

59

59

Apr.

9.5

10

12

12

12

11

12

12

12

13

Day

11

12

13

14

15

16

17

18

19

20

Mean monthly discharge, in second

Feb.

991

119

18

65

17

17

17

85

114

17

Mar.

362

605

251

108

103

89

86

72

68

56

Apr.

14

13

14

15

15

15

16

16

17

17

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

17

17

17

17

17

17

948

2,710

320 

17,800,

Mar.

46

36

27

22

20

19

18

16

12

9

9

368 

82,650

Apr.

18

18

17

30

180

18

16

16

16

83

22.6 

1,350

gage height, in feet, and discharge, in second-feet, at indicated time, 1958

M

1

2

3

4

5

6

7

a

9

10

11

N

1

2

3

4

5

6

7

a

9

10

11

M

FeetjSeo.ft.

February 27

2.61

2.60

8.60

2.91

4.35

3.96

3.58

3.48

6.50

7.40

7.40

7.80

6.60

6.10

5.40

5.07

4.95

4.45

4.07

3.58

3.24

3.12

3.05

3.01

170

168

168

230

683

526

386

374

2,080

2,820

2,820

2,630

8,100

1,700

1,880

1,020

965

788

565

404

305

277

861

258

Feet Sec. ft.

February 88

3.00

4.05

3.95

3.90

6.35

5.47

10.80

11.85

10.10

7.75

6.50

5.70

4.97

5.00

4.17

3.73

3.59

3.46

3.37

3.51

7.40

12.10

9.50

13.70

250

558

523

505

1,900

1,260

,7,770

8,640

6,470

3,190

8,020

1,410

976

990

603

. 449

407

368

341

383

8,820

.10,400

5,510

14.500

Feet jsec.f.t.

March 1

10.30

7.55

6.15

5.08

4.50

4.80

3.99

3.80

3.60

3.47

3.38

3.31

3,30

3.89

3.88

3.86

3.86

3.86

3.26

3.86

7.95

6,820

2,970

1,740

1,030

750

615

537

500

470

410

371

344

383

380

318

315

310

310

310

310

310

3.420

Feet Sec. ft.

March 2

8.35

7.30

7.33

11.05

14.00

12.70

14.30

14.58

14.70

14.85

12.00

9.80

10.60

10.85

10.2

8.52

10.95

8.89

7.48

6.58

5.98

5.55

5.20

3,890

8,730

2,770

8,840

15,300

11,800

16,200

17,000

17,300

17,700

10,800

 ,990

7,390

6,730

6,640

4,100

8,050

4,580

8,900

2,030

1,560

1,310

Ir 100

Feet Seo.ft.

March 3

Feet | Sec. ft.

March 4

Supplemental record.- Mar. 2, 9*40 a.m., 15.85 ft., 19,000 sec.-ft.
BALLONA CKEBK BASIN 866

Benedict Canyon storm drain at Culver City, Calif.

Location.- Water-stage recorder, lat. 34°01'23N , long. 118*23'00", in Rlnoon de los 

Bueyes grant, 400 feet south of Pacific Electric Railway, on east side of Wesley 

Street, Culver City, Los Angeles County. Altitude, about 96 feet.

Drainage area.- 6.96 square miles.

Page-height record.- Water-stage recorder graph.

Discharge record.- Discharge through 90-inch concrete pipe, computed by Ruttor's 

formula"

Maxima.- 1938s Discharge, 648 second-feet 7:10 a.m. Mar. 2 (gage height, 7.0 feet). 

1935-37! Discharge, 248 second-feet Feb. 12, 1936.

Remarks.- Record good. No regulation or diversions. Records furnished by Los Angeles 

County Flood Control District, through H. E. Hedger, chief engineer, and by Corps 

of Engineers, U. S. Army.

Mean dally diecharge, in second-feet, 1938

February 28 

March 1 

March 2 

March 3

Runoff, in acre -feet

128 

65 

308 

91

1,170

Gage height, in feet, and discharge, In second-feet, at indicated time, 1938

§

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7 

8

9

10

11

M

Feet Sec.ft.

February 27

1.00

1.00

1.00

.83

21

21

21

14

Feet Sec. ft.

February 28

0.8tL

.83

.90

.97

.98

5.08

3.50

2.90

2.00

2.00

1.98

1.90

1.58

1.1B 

1.18

4.35

3.60

4.60

5.10

13

14

17

20

20

482

269

191

87

87

85

78

55

30 

30

384

282

418

485

Feet Seo.ft.

March 1

2.50

1.97

1.94

1.71

1.47

1.27

1.15

1.14

2.50

140

85

81

64

48

35

29

28

140

Feet Seo.ft.

March 2

2.30

2.18

4.00

6.30

6.02

6.40

6.65

6.15

5.93

4.80

2.95

3.50

3.62

3.50

3.23

3.70

3.10

2.86

2.69 

2.53

2.40

2.30

2.22

2.18

117

104

337

617

592

624

640

605

583

445

197

269

285

269

234

295

217

186

164 

144

128

117

108

104

Feet Seo.ft.

March 3

2.16

2.14

2.12

2.12

2.09

2.03

2.01

1.90

1.72

102

100

98

98

95

90

88

79

64

Feet Seo.ft.

March 4

1.62 57

Supplemental record.- Mar. 2, 7:10 a.m., 7.0 ft., 648 sec.-ft.
266 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Topanga Creek BaaIn 

Topanga Creek near Topanga Beach, Calif.

Location.- Water-stage recorder, lat. 340 03'50n , long. 118°35'1011 , in Boca de Santa 

Monica grant, at highway bridge, 2 miles north of Topanga Beach, Los Angeles County. 

Altitude, about 270 feet.

Drainage area.- Area, 17.9 square miles. Average altitude, 1,355 feet. Maximum altltude, 2,477 feet. Average slope, 40 percent. Length of the main-stream channel,'6.4 

miles. Average slope of the main stream channel, 5.2 percent.

Sage-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 6,100 second-feet; extended above to slope-area determination of peak dIscharge.

Maxima.- 1938: Discharge, 7,960 second-feet 9:40 a.m. Mar. 2 (gage height, 11.20 feet). 

1930-371 Discharge, 4,510 second-feet Dec. 31, 1933.

Remarks.- Records, except those for Feb. 27 to Mar. 4, furnished by Los Angeles County 

Flood Control District, through H. E. Hedger, chief engineer.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

213

3.1

135

86

48

31

18

9

49

16

Mar.

501

2,670

269

101

63

46

36

36

33

33

Apr.

6

6

5.5

5.5

5.5

4.8

5

5

5.5

5.5

Day

11

12

13

14

15

16

17

18

19

20

Feb.

239

147

63

28

16

7

5

4.8

5

4.1

Mar.

49

213

209

81

53

34

21

21

22

22

Apr.

6

6

6

4.8

4.8

4.3

3.4

3.4

3.4

3.4

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

4.1

3.9

3.6

3.3

1.9

1.9

12

643

3,570

Mar.

23

23

23

21

16

13

11

10

9

7.5

5.5

9,270

Apr.

3.4

3.2

2.6

2.9

3.2

2.9

3.4

4.3

4.6

5.5

4.53

270

Discharge, In second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

H

Feb. 27

8.5

8.5

8.4

8.3

8.4

8.5

8.4

8.3

8.5

13

10

14

18

21

23

37

41

39

35

33

29

29

28

26

Feb. 28

28

29

35

55

113

136

302

449

935

1,730

1,140

793

546

370

278

219

185

173

200

355

1,120

2,940

1,890

2,810

Mar. 1

2,090

1,750

1,720

977

732

514

400

325

275

233

202

169

149

134

123

114

109

103

100

95

89

89

87

94

Mar. 2

134

206

259

679

1,700

2,410

4,370

4,160

5,580

7,020

4,950

4,525

6,490

4,840

4,490

3,590

2,420

l.,680

1,280

1,020

815

669

593

526

Mar. 3

464

414

376

345

334

339

355

307

294

278

252

240

238

224

217

208

202

189

181

175

167

162

158

155

Mar. 4

148

143

137

131

128

121

117

112

108

104

100

96

92

89

85

81

78

78

77

75

73

71

70

70

Supplemental record.- Mar. 2, 9:40 a.m., 11.20 ft., 7,960 

sec.-ft.
RECORDS OF STAGE AND DISCHARGE AT STREAM-GAQINQ STATIONS 

Malibu Creek Basin

Halibu Creek at Crater Camp, near Calabasas, Calif.

Location.- Water-stage recorder, lat. 34°04'30n , long. 118°42'10n , in SWi sec. 18, T. 

IS., R. 17 W., a quarter of a mile below Crater Camp, and 6 miles southwest of 

Calabasas. Altitude, about 460 feet.

Drainage area.- Area, 103 square miles. Average altitude, 1,226 feet. Maximum altitude, 3,050 feet. Average slope, 38 percent. Length of main stream channel, 17.5 

miles. Average slope of the main stream channel, 6.9 percent.

Page-height record.- Water-stage recorder graph except Mar. 3-8.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

1,200 second-feet and extended above to estimated maximum discharge. Record Mar- 3- 

8 obtained by comparison with adjacent stations and'one current-meter measurement

Discharge, 10,000 second-feet 1 p.m. Mar. 2 (gage height, 15.9 feet). 

Discharge, 9,650 second-feet Jan. 1, 1934 (gage height, 13.73 feet).

Maxima.- 1931-37: 1938s 

Remarks.- Records furnished by Los Angeles County Flood.Control District, 

H. E. Hedger, chief engineer.

Mean dally discharge, in second-feet, 1938

through

Day

1

2

3

4

5

6

7

8

9

10

Feb.

146

38

100

86

32

26

25

25

37

28

Mar.

1,960

5,090

1,600

609

330

250

190

150

123

98

Apr.

27

25

26

24

24

22

21

19

18

20

Day

11

12

13

14

15

16

17

18

19

20

Feb.

300

185

61

42

39

29

23

22

30

13

Mar.

103

835

809

509

299

190

135

109

96

87

Apr.

19

19

19

18

18

18

16

15

13

13

Day

21

22

23

24

25

26

27

26

29

30

31

 Runoff, in acre-feet .........................................

Feb.

11

12

12

12

12

12

19

612

3,950

Mar.

77

66

60

56

56

55

53

55

57

56

41

28,170

Apr.

14

14

14

13

13

13

12

12

12

11

1,040

Qage height, in feet, and discharge, in second-feet, at indicated time, 1938

a

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec.ft.

February 27

Feet | Sec. ft.

February 28

4.98

5.13

5.52

6.15

6.55

6.90

7.50

7.15

7.00

6.50

6.55

6.70

7.00

8.00

9.80

10.95

13.00

40

56

108

235

344

443

666

518

455

293

302

344

455

895

2,050

3,060

5,420

Feet j Sec. ft.

March 1

13.15

12.85

11.90

8.00

7.67

7.37

7.10

6.90

6.70

6.70

5,750

5,290

4,120

995

830

686

578

498

431

431

Feet [Sec.ft.

March 2

7.05

7.50

8.70

9.90

11.35

-is.oos

14.00

14.20

15.70

15.15

14.90

15.90

530

710

1,360

2,220

3,550

5,520

6,850

7,150

 9,640

8,710

8,300

10,000

9,300

8,200

7,200

5,200

4,000

3,300

2,800

Feet | Sec.ft.

March 3

Feet Sec.ft.

March 4
268 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 

Santa Clara River Baaln

Santa Clara River near Saugus, Calif.

Location.- Water-stage recorder, lat. 34025'42lt , long. 118035 l 23n , In San Francisco 

grant, on pier of old highway bridge, 3 miles vest of Saugus, Los Angeles County.

Drainage area.- 355 square miles.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation poorly defined. Shifting-control eorreetlons used throughout period. Discharge determined by comparison with adjacent 

stations Feb. 6-9, ia-26, Mar. 5-9, 17, 18. Discharge Mar. 22 to Apr. 30 determined 

by Interpolation between discharge measurements.

Maxima.- 1938: 1929-37: Discharge, 24,000 second-feet (estimated) 7130 p.m. Mar. 

Discharge, 3,870 second-feet Jan. 1, 1954.

2.

Remarks.- Slight regulation at reservoirs In Bouquet and Dry Canyons. Records furnished by Los Angeles County Flood Control District, through H. K. Hedger, chief 

engineer.

Meanjlally discharge, In second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

38

.4

58

11

5

4

4

4

4

4

Mar.

349

6,370

2,310

394

102

65

84

46

46

67

Apr.

51

44

37

30

24

18

11

11

11

11

Day

11

12

13

14

15

16

17

18

19

90

Feb.

175

20

1.5

1.4

1.3

1.2

1.1

1.0

1.1

1.0

Mar.

80

275

513

306

99

67

43

49

68

84

Apr.

11

10

10

10

10

10

10

10

10

9.5

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0.9

.8

.7

.6

.5

.5

2.0

113

908

Mar.

89

88

87

86

85

84

84

78

71

64

58

24,380

Apr.

9.5

9.5

9

9

9

9

9

8.5

8.5

8.5

14.6

869

Discharge, In second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

March 2

100

150

300

450

450

900

1,350

1,600

1,650

1,800

2,200

2,700

3,100

5,200

5,900

11,300

16,000

21,500

23,400

20,000

12,500

10,000

7,000

5,500

March 3

4,700

3,900

3,500

3,000

2,800

2,600

2,650

2,650

2,500

2,400

2,300

2,200

2,100

2,000

2,000

1,950

1,550

1,400

1,300

1,200

1,150

1,050

1,000

1,000

Supplemental records.- Mar. 2, 7.S30 p.m., 24,000 sec.-ft.
SANTA CLARA RIVER BASIN 269

Plru Creek* near Plru, Calif.

Location.- Water-stage recorder, lat. 34*25'30", long. 118°46'46n , In southern part of 

Tenesoal grant, about 1-3/4 miles northeast of Plru, Ventura County, and 2 miles upstream from Junction with Santa Clara River. Altitude, about 780 feet.

Drainage area.- Area, 438 square miles. Average altitude, 4,800 feet. Maximum altltude, B.BOO feet. Average slope, 35.5 percent. Length of main stream channel, 54 

miles. Average slope of main stream channel, 2.8 percent.

Page-height record.- Water-stage recorder graph except 18 m. Mar. 8 to 18 m. liar. 4.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

8,110 second-feet; extended logarithmically to peak discharge determined by slopearea method. Shifting-control corrections applied during period of record. Discharge from 12 m. Mar. 8 to 12 m. Mar. 4 and Mar. 13-81 determined from comparative 

hydrograph based on records of Santa Paula Creek near Santa Paula and Coyote Greek 

near Ventura.

Maxima.- 19381 Discharge, 35,600 second-feet ItSO p.m. Mar. 8. 

 1911-13, 1927-37J Discharge, 15,800 second-feet Feb. 9, 1938.

Remarks..- Records fair. Flood flow not affected by diversions, 

cooperation with Ventura County Water Survey.

Mean daily discharge, in second-feet, 1938

Station maintained in

Day

1

2

3

4

5

6

7

8

9

'10

Feb.

667

159

655

440

198

95

45

37

199

894

Mar.

5,510

13,140

4,960

8,110

1,560

1,150

774

748

678

618

Apr.

838

881

881

881

884

884

817

815

810

2C8

Day

11

12

13

14

15

16

17

18

19

80

Feb.

8,610

681

418

300

845

808

188

188

833

181

Mar.

655

1,530

819

760

700

680

550

58C

490

450

Apr.

198

195

198

801

194

165

150

138

133

186

Day

21

82

83

84

26

86

27

88

29

30

31

Feb.

160

150

130

187

180

111

114

1,610

376

20.910

Mar.

4CO

395

405

400

376

347

317

888

873

856

848

1,566

83,560

Apr.

185

184

184

118

187

186

118

180

120

126

170

10,150

gage height, in feet, and discharge, in second-feet, at indicated time, 1986

i

i

9

3

4

S

6

7

8

9

10

11

N

1

8

5

4

6

6

7

8

9

10

11M

Feet (Bee. ft.

February 27

Feet f Sec. ft.

February 28

3.00

3.13

3.45

3.55

3.65

3.93

3.82

3.98

4.03

4.08

3.96

3.98

3.97

3.93

3.98

4.08

4.19

4.53

5.20

6.80

7.10

134

177

337

484

606

1,100

964

1,880

1,680

1,610

1,580

1,550

1,640

1,490

1,480

1,610

1,850

8,340

3,600

5,460

7.650

Feet

Mai

6.70

6.46

6.25

6.00

6.15

6.80

7.16

6.70

6.25

5.94

5.65

5.45

5.85

5.10

.90

.66

.76

.66

.66

.61

.48

.44

.45

.48

Seo.ft.

oh 1

6,700

6,380

5,960

5,660

5,960

7,450

8,480

7,660

6,600

6,140

5,560

5,150

,960

,860

,680

,680

,590

,400

,380

,840

,310

,830

,850

.810

Feet Iseo.ft.

March 2

4.57

4.76

5.10

5.35

5.87

6.70

7.30

7.60

7.80

8.10

9.15

11.70

14.00

4,440

4,790

5,460

6,380

7,690

9,900

11,600

18,000

18,800

13,800

17,800

85,900

34,600

30,000

85,000

16,000

14,000

12,000

11,000

9,800

9,800

8,500

8,000

7.500

Feet | See. ft.

Maroh 5

7,000

6,600

7,500

6,800

5,800

5,400

4,300

3,600

3,600

3,300

3,000

8,700

Feet Iseo.ft.

Maroh 4

8,300

8,130

8,010

Supplemental record.- Mar. 8, USD p.m., 35,600 sec.-ft.
S70 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Seape Creek near Fillmore, Calif.

Location.- Water-atage recorder, lat. 34°26'55", long. 118°55'35", in NEi aeo. 12, T. 

4 N., R. 20 W., 0.1 mile downstream from Junction with Little Sespe Creek, and 34 

miles north of Fillmore. Altitude, about 590 feet.

Drainage area.- Area, 254 square miles. Average altitude, 4,040 feet. Maximum altltude, 7,480 feet. Average slope, 37 percent. Length of main stream channel, 44 

miles. Average slope main stream channel, 2.9 percent.

Sage-height 50"! record.- Water-atage recorder graph Feb. 1-11; no record Feb. 12 to Apr. 

Discharge record.- Stage-discharge relation defined by current-meter meaaurements below 

2,160 aeoond-f&et; extended logarithmically to peak discharge determined by slopearea method. Shifting-control corrections applied for period of record. Discharge 

for Feb. 12 to Apr. 30 determined from comparative hydrograph baaed on Santa Paula 

Oreek record, nine current-meter measurements, and slope-area determination of peak 

discharge.

Maxima.- 1938: Discharge, 56,000 second-feet about 2 p.m. Mar. 2. 

1927-37: Diacharge, about 34,000 second-feet Dec. 31, 1933.

Remarks.- Records'fair except those for Feb. 1-11, which are good. No diversions above 

gage. Station maintained in cooperation with Ventura County Water Survey.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

2,560

301

4,320

1,620

672

396

354

343

956

1,400

Mar.

3,800

14,840

7,090

4,110

2,920

2,350

2,120

2,080

1,840

1,600

Apr.

370

350

340

340

339

328

314

295

277

260

Day

11

12

13

14

15

16

17

18

19

20

Feb.

10,680

2,160

970

758

660

600

580

566

572

480

Mar.

1,810

4,410

3,000

2,100

1,600

1,290

1,110

960

880

820

Apr.

244

230

220

210

200

193

185

180

177

177

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

430

384

344

290

261

257

262

1,570

1 9 A1

68,920

Mar.

775

700

640

586

550

520

49C

460

435

418

398

2

1 co

132,300

Apr.

177

177

177

177

180

176

174

172

171

170

O'st'se

13,840
SANTA CLARA RIVER BASIN 271

Santa Paula <Jreek near Santa Paula, Calif.

Location.- Water-stage recorder, lat. 340 23'40", long. 119°04'3511 , near-east boundary

 of Ex Mission San Buenaventura .grant, 50 feet upstream from Santa Paula Water Works 

diversion dam, and about 3 miles north of Santa Paula, Ventura County. Altitude, 

about 650 feet.

Drainage area.- Area, 39.8 square miles. Average altitude, 3,220 feet. Maximum alti-

 tude, 6,704 feet. Average slope, 44 percent. Length of main stream channel, 10 

miles. Average slope of main stream channel, 11 percent.

Page-height record.- Water-stage recorder graph except 6 p.m. Mar. 2 to 6 p.m. Mar. 4,

 and 1 p.m. Mar. 12 to 1 p.m. Mar. 14. Gage heights interpolated 6 p.m. to 12 p.m. 

Mar. 2 and 1 p.m. Mar. 12 to 1 p.m. Mar. 14.

Discharge record.- Stage-discharge relation defined by current-meter measurements below

 676 second-feet; extended logarithmically to peak discharge determined by slope-area 

method. Shifting-control corrections applied to gage-height record. Discharge Mar. 

3 and 4 determined from comparative hydrograph.

Maxima.- 1938: Discharge, 13,500 second-feet 2 p.m. Mar. 2 (gage height, 10.56 f.eet).

 1927-37: Discharge, about 10,000 second-feet Dec. 31, 1933.

Remarks.- Records good except those for Mar. 2-4 and 12-14, which are fair. Flood flow 

not affected by diversion above gage. Station maintained in cooperation with Ventura County Water Survey.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

287

48

819

312

120

90

81

79

144

166

liar.

683

3,040

1,100

639

434

339

299

299

269

247

Apr.

90

81

79

79

77

72

68

66

61

61

Day

11

12

13

14

15

16

17

18

19

20

Feb.

771

384

201

155

108

95

95

90

98

88

Mar.

299

754

565

400

326

280

247

225

211

201

Apr.

59

58

53

48

45

44

43

42

42

45

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

85

81

77

66

62

61

66

410

10,190

Mar.

196

174

151

140

133

124

117

111

108

101

95

 XQrt

24,410

Apr.

44

44

43

45

51

44

42

39

43

44

55.1

3,280

Page height, in feet, and discharge, in seoond-feet, at indicated time, 1938

!

l

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

If

Feet | Sec. ft.

February 27

Feet Sec. ft.

February 28

2.58

2.58

2.59

2.63

2.75

2.64

2.95

3.12

3.07

3.07'

3.10

3.15

3.15

3.23

3.20

3.15

3.12

3.10

3.10

3.25

3.72

4.48

4.90

4.98

68

68

70

79

111

140

182

275

247

247

264

299

299

352

332

299

280

275

275

372

735

1,507

1,990

2.104

Feet Sec.ft.

March 1

4.50

4.22

4.05

3.95

3.85

3.75

3.70

3.65

3.60

3.55

3.50

3.46

3.42

3.40

3.38

3.35

3.33

3.31

3.30

3.28

3.26

3.28

3.32

3.40

1,540

1,230

1,060

960

865

778

735

692

650

610

570

538

506

490

478

455

441

427

420

406

393

406

434

490

Feet Sec.ft.

March 2

3.60

3.75

3.95

4.45

4.90

4.93

4.80

4.72

4.80

5.50

7.12

7.25

8.55

10.56

7.95

6.00

5.00

4.35

4.17

4.05

3.97

3.88

3.82

3.77

650

778

960

1,480

2,000

2,040

1,880

1,780

1,880

2,810

5,540

5,800

8,450

13,500

7,800

4,050

2,530

1,700

1,510

1,380

1,290

1,190

1,130

Ir 080

Feet Sec.ft.

March 3

1,060

1,030

1,350

1,550

1,780

1,500

1,160

1,120

1,180

1,210

1,150

1,OPO

1,060

1,030

1,000

970

950

920

900

880

860

840

820

800

Feet Sec.ft.

March 4

750

660

600

545
878 FLOODS OF MARCH 1936 IN SOUTHERN CALIFORNIA 

Ventura River BaaIn

Uatllija Oreek at Matlllja, Calif.

ooation.- Water-stage recorder, lat. 34°29'06n , long. 

~~~" R. 133 W., half a mile northwest of Matlllja.

119° 18'30", in NEj seo. 29, T. 

Altitude, about 970 feet.

area.- Area, 55 square miles. Average altitude, 3,630 feet. Maximum altl6,025 feet. Average slope, 47 percent. Length of main stream channel, 13.7 

Average slope of main stream channel, 6.6 percent.

Page-height record.- Water-stage recorder graph except 10 a.m. Mar. 2 to Mar. 4 and 

Mar. §8 to Sept. 30.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

800 second-feet; extended to slope-area determination of peak discharge. Discharge 

10 a.m. Mar. 2 to Mar. 4 and Mar. 28 to Sept. 30 based on 43 discharge measurements 

and comparative hydrograph.

Maxima.- 1938: Discharge, 15,900 second-feet 12:30 p.m. Mar. 2.

1927-37: Discharge, 7,000 second-feet Dec. 31, 1933 (gage height, 7.20 feet).

Remarks.- Records good, except those for Mar. 2-4, and Mar. 28 to Apr. 30, which are 

fair. No diversions above gage. Station maintained In cooperation with Ventura 

County Water Survey.

Mean dally discharge, in second-feet, 1936

Day

1

2

3

4

5

6

7

8

9

10

Feb.

427

66

516

266

155

111

90

81

235

319

Mar.

666

4,850

2,120

1,260

1,270

816

765

786

694

632

Apr.

170

160

150

147

143

137

129

122

116

112

Day

11

12

13

14

15

16

17

IS

19

20

Feb.

1,970

766

408

332

262

217

191

188

175

157

Mar.

792

1,660

1,350

616

544

480

445

412

377

356

Apr.

109

105

96

69

83

79

76

76

76

82

Day

21

28

23

24

86

26

27

26

S9

30

31

Feb.

143

134

123

115

113

113

111

410

293

16,260

Mar.

332

313

294

276

262

245

232

220

205

192

162

48,170

Apr.

62

62

82

66

95

66

66

83

83

79

103

6,150

Page height, In feet, and discharge, in second-feet, at Indicated time, 1936

n

1

2

3

4

5

6

7

 6

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec.ft.

February 27

Feet Sec.ft.

February 26

2.94

2.94

2.95

3.00

3.06

3.14

3.19

3.22

3.23

3.24

3.24

3.24

3.23

3.22

3.21

3.20

3.20

3.19

3.25

3.50

4.15

5.50

6.30

6.20

109

109

111

123

136

157

170

180

183

188

188

188

188

185

183

183

183

183

202

287

597

1,760

2,700

2.570

Feet Sec.ft.

March 1

5.60

5.20

4.95

4.80

4.55

4.40

4.35

4.35

4.40

4.43

4.43

4^46

4.30

4.15

4.10

4.07

4.02

3.98

3.92

3.89

3.93

3.95

4.05

4.20

1,940

1,500

1,270

1,140

948

840

808

608

856

880

888

910

793

694

670

654

626

597

561

538

561

573

626

712

Feet Sec.ft.

March 2

4.35

4.70

5.07

5.35

6.30

6.75

6.40

6.65

6.50

608

1,070

1,410

1,700

2,810

3,640

2,920

3,380

3,070

7,000

13,000

15,000

14,000

8,500

6,500

5,500

4,600

4,100

 3,700

3,400

3,100

2,800

2,700

2.550

Feet See. ft.

March 3

2,450

2,350

2,700

3,600

3,600

2,800

2,400

2,200

2,120

2,060

2,000

1,940

1,880

1,830

1,780

1,740

1,700

1,670

1,630

1,600

1,570

1,540

1,510

1.490

Feet Sec.ft.

March 4

1,420

1,310

1,230

1,180

Supplemental record.- Mar. 2, 12:30 p.m., 15,900 see.-ft.
VENTURA RZVBR BASIN 873

Ventura River near Ventura, Calif.

^.-Water-stage recorder, lat. 34C 20'55B , long. 119°18'20", in southeast corner 

Shta Ana grant, at highway bridge at entrance to Foster Memorial Park, a quarter

of a mile downstream from Ventura diversion dam and Coyote Oreek, and 6 miles north

of Ventura, Ventura County. Altitude, about 210 feet.

 ea.- Area, 187 square miles. Average altitude, 2,310 feet. Maximum altile, 6,025 feet. Average slope, 46 percent. Length of main stream channel, 23.7 

miles. Average slope of main stream channel, 5 percent.

Page-height record.- Water-stage recorder graph except 1 p.m. Mar. 2 to 9:30 a.m. Mar. 3. 

Peak gage height observed.

Dis _; record.- Stage-discharge relation defined by current-meter measurements below 

e,600 second-feet; extended to slope-area determination of peak discharge. Discharge 

1 p.m. Mar. 2 to 9:30 a.m. Mar. 3 based on hydrograph.

Maxima.- 1936: Discharge, 39,200 second-feet 2:15 p.m. Mar. 2 (gage height 19.2 feet).

1911-13, 1929-37: Discharge, 23,000 second-feet Dec. 31, 1933 Tgage height, 

14.6 feet).

Remarks.- Records good. Flood flow not affected by diversions, 

cooperation with VentUfa County Water Survey.

Mean daily discharge, in second-feet, 1936

Station maintained in

Day

1

2

3

4

5

6

7

6

9

10

Feb.

1,700

174

1,540

612

406

264

206

177

421

494

Mar.

2,690

17,950

6,970

2,770

1,660

1,300

1,100

1,310

1,020

682

Apr.

304

288

267

257

257

247

237

228

228

219

Day

11

12

13

14

15

16

17

18

19

20

Feb.

6,410

1,890

632

730

524

407

341

301

295

255

Mar.

1,190

5,840

3,060

1,880

1,480

1,170

1,010

848

746

652

Apr.

219

219

219

206

197

188

180

172

161

165

Day

21

22

23

24

26

26

27

28

29

30

31

Feb.

231

206

201

197

185

182

182

1,060

737

40,910

Mar.

592

541

510

478

449

421

400

381

363

344

321

1,953

120,100

Apr.

161

153

149

161

184

165

149

149

146

153

201

11,960

Page height, in feet, and discharge, in second-feet, at indicated time, 1958

W

1

2

3

4

6

6

7

8

9

10

11

N

1

2

5

4

5

6

7

8

9

10

11

H

Feet | Sec. ft.

February 27

Feet jseo.ft.

February 28

6*30

r

>6.50

6.59

6.58

6.56

6.54

6.52

6.52

6.51

6.59

7.00

8.70

10.45

11.65

185

J1

> 279

1

1

J

530

324

312

301

290

290

284

330

660

3,620

9,000

13,420

Feet Sec. ft.

March 1

11.70

10.80

9.85

9.20

8.75

8.38

8.16

8.00

7.85

7.80

7.72

7.60

7.50

7.40

7.30

7.15

7.05

7.01

6.98

6.95

6.95

6.95

6.97

7.05

13,600

10,270

6,950

4,970

3,780

2,870

2,380

2,060

1,790

1,700

1,570

1,380

1,290

1,150

1,020

832

722

680

651

622

622

622

642

722

Feet Sec. ft.

March 2

7.40

7.85

8.18

8.95

10.40

12.00

11.70

11.82

12.25

12.60

13.80

16.00

17.35

1,150

1,860

2,510

4,390

8,970

14,870

13,760

14,200

15,800

16,940

21,500

29,260

34,000

38,700

35,000

29,500

26,500

23,900

21,800

19,400

17,700

16,000

14,600

13,500

Feet Seo.ft.

March 3

8.48

8.40

8.30

8.20

8.10

8.10

8.10

8.08

7.84

7.75

.7.67

7.61

7.55

7.49

7.43

12,200

11,700

10,700

10,000

9,400

8,600

8,000

7,500

7,100

6,580

6,360

6,060

5,790

5,530

5,530

5,560

5,500

4,900

4,650

4,460

4,300

4,140

4,000

3.850

Feet | Sec. ft.

March 4

\

>7.35

)

\

>7.23

>

\

>7.12

)

\

[ 6.99

>

\

U.87

)"\

U.73

J

I. >6.63«

)

\

U.56

;

s

>3,660

)

1

>3,390

J

3,150

2,880

 j

U,620

J

N

^2,340

 >

\

^2,140

J

V

U,000

)

Supplemental record.- Mar. 2, 2:15 p.m., 19.2 ft., 39,200 sec.-ft.
274 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Coyote Creek near Venture, Calif.

Location.- Water-stage recorder, lat. 34°21 ! 20n , long. 119°18 l 50n , near southeast corner of Santa Ana grant, 200 feet downstream from highway bridge, half a mile upstream from junction with Ventura River, and 5j miles northwest of Ventura, Ventura 

County. Altitude, about 250 feet.

Drainage area.- Area, 41.1 square miles. Average altitude, 1,590 feet. Maximum altitude, 4,870 feet. Average slope, 34 percent. Length .of main stream channel, 11.0 

miles. Average slope of mainstream channel, 7.9 percent.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

525 second-feet; extended to slope-area determination of peak discharge.

Maxima.- 1938: Discharge, 11,500 second-feet 1:30 p.m. Mar. 2 (gage height, 12.00 feet). 

1927-32, 1933-37: Discharge, 5,600 second-feet Feb. 14, 1937.

Remarks.- Records good. No diversions above gage. Station maintained in cooperation 

with Ventura County Water Survey.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

465

54

303

254

100

51

36

28

96

91

Mar.

524

3,470

800

350

247

162

157

142

120

106

Apr.

34

32

31

28

27

27

27

27

26

25

Day

11ie

13

14

15

16

17

18

19

20

Feb.

663

271

131

104

71

61

50

44

51

37

Mar.

173

516

303

190

145

122

102

91

80

72

Apr.

25

25

24

24

23

22

21

20

- 19

18

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

31

30

26

25

21

20

20

328

6,870

Mar.

66

62

61

59

58

51

48

46

42

38

36

orro

16,740

Apr.

18

18

16

16

15

15

14

14

14

16

1,310

Gage height, in feet, and discharge, in second-feet, at indicated time, 1938

1

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

H

Feet [ Sec. ft.

February 27

Feet Sec.ft.

February 28

1.95

1.95

2.00

2.04

2.07

2.10

2.19

2.30

2.30

2.40

2.61

2.61

2.56

2.48

2.41

2.39

2.37

2.34

2.40

2.70

3.29

6.10

 6.49

6.00

19

19

22

28

32

36

47

62

64

79

118

118

99

93

80

79

76

71

82

145

338

2,320

2,720

2.270

Feet Sec.ft.

March 1

5.20

4.60

4.31

4.13

4.00

3.75

3.62

3.51

3.48

3.39

3.31

3.27

3.22

3.19

3.13

3.10

3.08

3.04

3.00

2. -99

2.97

2.98

3.02

3.41

1,550

1,080

896

788

713

578

514

463

449

409

373

357

338

326

303

291

284

268

257

254

247

250

264

418

Feet Sec.ft.

March 2

3.56

3.60

3.69

3.86

6.91

8.20

8.01

7.34

6.89

7.61

9.51

10.32

11.15

11.79

8.71

7.01

6.11

5.66

5.26

4.98

4.79

4.64

4.51

4.38

486

504

548

636

3,240

4,950

4,680

3,790

3,220

4,140

6,940

8,310

9,840

11,000

5,650

3,360

2,380

,1,950

1,600

1,370

1,280

1,110

1,020

938

Feet Sec.ft.

March 3

4.31

4.25

4.31

4.91

5.11

4.57

4.39

4.38

4.43

4.34

4.21

4.11

4.01

3.97

3.96

3.89

3.94

3.95

3.89

3.88

3.69

3.65

3.61

3.58

896

860

896

1,320

1,470

1,050

938

926

956

902

818

759

702

674

669

625

652

658

620

614

514

495

476

458

Feet Sec.ft.

March 4

Supplemental record.- Mar. 2, 1:30 p.m., 12.00 ft., 11,500 sec.-ft.
RECORDS OP STAGE AND DISCHARGE AT STREAM-GAGIMG STATIONS 

Santa Ynez River Basin

275

Santa Ynez River at Juncal Reservoir, near Honteclto, Calif.

Location.- Waiter-stage recorder, lat. 34°29'30lt , long. IIS'SO'SO", In sec. 28, T. 5 

N., R. 25 W. , at Juncal Reservoir dam, 8.5 miles northeast of Montecito. Altitude 

of stream bed, about 1,950 feet.

Drainage area.- Area, 16.0 square miles. Average altitude, 3,550 feet. Maximum altltuae, 6,025 feet. Average slope, 64 percent. Length of main stream channel, 5.2 

miles. Average slope .of main stream channel, 15 percent.

Sage -height record.- Water-stage recorder graph.

Discharge record.- Discharge computed from reservoir gage-height record, rainfall, 

evaporation, release, and overflow.

Maximum.- 1938: Mean hourly discharge, 4,160 second-feet Mar. 2.

Remarks . - No diversion during flood period. Record furnished by Montecito County Water 

 BTstrict.

Mean, dally discharge. In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

162

85

194

85

30

17

11

10

29

57

Mar.

272

1,240

467

197

116

89

119

185

125

87

Apr.

32

32

32

32

31

32

31

31

31

31

Day

11

12

13

14

15

16

17

18

19

20

Feb.

585

147

71

32

26

26

13

13

15

17

Mar.

78

509

293

159

124

97

75

61

47

42

Apr.

29

29

28

29

28

27

27

27

27

15

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

15

13

14

12

10

10

10

15

3,420

Mar.

38

47

49

41

38

37

34

35

32

30

25

155

9,500

Apr.

15

13

16

22

25

23

22

19

19

21 '

1,540

Discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

&

9

10

11

11

March 1

943

625

519

419

343

290

252

208

188

170

157

153

140

129

129

124

115

110

105

105

110

110

115

124

March 2

135

163

195

260

563

891

1,050

1,030

1,010

1,140

1,720

2,550

3,740

4,160

3,450

2,440

1,790

1,460

1,200

1,010

868

752

667

605

March 3

547

519

510

547

595

557

547

527

481

437

384

375

375

375

367

343

320

297

290

275

260

253

246

233

March 4

233

233

226

206

200

195

195

195

195

189

189 '

189

189

189

182

182

176

163

157

152

146

140

135

135
276 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Santa Ynez River near Santa Barbara, Calif 

location.- Water-stage recorder, lat. 340 31 I 40M , long. 119e 41'00tl , about on line between 

sees. 10 and 11, T. 5 N., R. 27 W., at Gibraltar Dam, 7 miles north of Santa Barbara. 

Altitude, about 1,200 feet.

Drainage area.- Area, 219 square miles. Average altitude, 3,400 feet. Maximum altltude, 6,828 feet. Average slope, 42 percent. Length of main stream channel, 17.5 

miles. Average slope of main stream channel, 6 percent.

Page-height record.- Water-stage recorder graph.

Discharge record.- Inflow computed from fluctuation In reservoir level.

Maximum.- 1938s Discharge (mean from 1:45 p.m. to 2 p.m.), 38,200 second-feet Mar. 2.

Remarks.- Records represent flow Into reservlor at Qlbralter Dam and are good. Regulation at Junoa1 Reservoir except during flood periods. Records furnished by City of 

Santa Barbara.

Mean da^ly discharge, In second -feet, 1938*

Day

1

2

3

4

5

6

7

8

9

10

Feb.

792

122

775

604

310

191

150

128

180

408

Mar.

1,390 **9,130

5,440

2,020

1,130

794

618

1,000

870

699

Apr.

222

216

210

203

201

198

188

180

174

168

Day

11

12

13

14

15

16

17

18

19

20

Feb.

4,400

1,630

552

406

351

276

247

244

252

207

Mar.

713

4,480

 2,620

1,560

1.100

835

669

562

491

450

Apr.

162

164

161

156

155

155

151

145

144

136

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

197

212

220

165

150

131

126

175

26,980

Mar.

405

340

334

328

312

300

280

267

259

248

231

1,286

79,090

Apr.

130

122

120

124

152

139

130

122

124

126

159

9,430

Discharges are for 24-hour period ending 6 p.m. of day Indicated. 

#* Mean discharge for calendar day Mar. 2, 11,300 second-feet.

Discharge, In second-feet, at Indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

March 1

489

467

431

526

582

641

718

March 2

781

895

1,290

1,870

2,830

4,600

6,170

6,940

7,390

8,790

12,800

21,300

31,300

35,200

29,500

22,200

16,900

13,800

11,700

19,300

8,340

7,370

6,630

6,020

March 3

5,600

5,320

5,100

4,930

4,300

4,660

4,490

4,280

4,120

4,020

3,330

3,740

3,590

3,460

3,350

3,230

3,120

2,990

Supplemental record.- Mar. 2, mean from 1:45 to 

2 p.m., 33,200 second-feet.
SANTA YNEZ RIVER BASIN 277

Santa Xhea River below Gibraltar Dam, near Santa Barbara, Calif.

Location. - Water-stage recorder, lat. 34°31'40", long. 119° 41 '00", about on line between BOOB. 10 and 11, T. 6 N. , R. 87 W., downstream from Gibraltar Dam, 7 miles

north of Santa Barbara. Altitude, about 1,800 feet.

Dra .- Area, 819 square miles. Average altitude, 3,400 feet. Maximum altl8 feet. Average slope, 48 percent. Length of main stream channel, 17.6

miles. Average slope of main stream channel, 6 percent 

Page -height record.- Water-stage recorder graph. 

Discharge

rat

- Discharge computed from rating of gate valve Feb. 

spillway, Feb. 8 bo Apr. 30.

18-17 and Mar. 1-6,

Maximum.- 19381 Discharge, 36,600 second-feet 8il6 p.m. Mar. 8.

Remarks.- Flow regulated by storage in reservoir and diversion to city of Santa Barbara; during flood period City of Santa Barbara diverted 149 acre-feet. No diversions from Gibraltar Reservoir Feb. 3-14 and Mar. 1 to Apr. 3. Records furnished 

by City of Santa Barbara.

Mean daily discharge, in second-feet

Day

1

2

3

4

6

6

7

8

9

10

Feb.

0

0

683

669

366

806

168

132

166

395

Mar.

1,360

«»8,630

6,960

8,160

1,170

821

632

981

888

714

Apr.

222

216

209

203

200

197

188

179

173

167

Day

11

12

13

14

16

16

17

18

19

20

Feb.

4,130

1,900

696

415

369

286

249

236

264

210

Mar.

696

4,320

2,730

1,610

1,130

863

683

670

497

464

Apr.

161

161

161

166

162

162

149

143

140

137

Day

21

22

23

24

26

26

27

28

29

30

31

Feb.

196

201

222

170

149

131

123

156

464

26,220

Mar.

410

346

333

330

316

301

283

268

269

249

234

I Q on

79,430

Apr.

129

120

117

121

163

137

129

.120

123

129

168

9,400

1938*

* Discharges are for 84-hour period ending 6 p.m. of day indicated.

** Mean discharge for calendar day Mar. 8, 10,900 second-feet.

Discharge, in second-feet, at indicated time, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

6

6

7

8

9

10

11

M

March 1

660

627

606

606

616

650

686

March 2

646

696

796

1,100

1,660

2,470

4,160

6,930

6,740

7,270

9,160

14,000

24,800

34,800

33,400

20,100

20,200

16,500

13,800

11,200

9,620

8,290

7,400

6,680

March 3

6,110

6,690

6,380

6,170

4,980

4,840

4,690

4,830 '

4,320

4,190

4,060

3,910

3,780

3,630

3,610

3,400

3,280

3,170

Supplemental record.- Mar. 2, 2H6 p.m. 

second-feet.

SB,600
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 

Santa Ynez River near Santa Ynez, Calif.

Location.- Water-stage recorder, lat. 34°35'20n , long. 120°01 I 25", in Canada de los 

Pinos grant, at San Harcos Road Bridge, 4 miles souttiaaat of Santa Toe z, Santa Barbara 

County. Altitude, about 500 feet.

Drainage area.- Area, 435 square miles. Average altitude, 2,890 feet. Maximum altltude, 6,828 feet. Average slope, 34 percent. Length, of main stream channel, 41.5 

miles. Average slope of main stream channel, 3 percent.

Sage-height record.- Water-stage recorder graph.

Dlacharge record.- Stage-discharge relation defined by current-meter measurements below 3,360 second-feet and by float measurements up to 34,100 second-feet; extended 

logarithmically to peak stage.

Maxima.- 1938: Discharge, 43,700 second-feet 6 p.m. Mar. 2 (gage height, 17.9 feet).

1929-31, 1932-37: Discharge, 7,990 second-feet Feb. 6, 1937 (gage height, 

10.67 feet).

Rei larks.- Records good. The cities of Santa Barbara and Monteclto divert water above 

gage. Flood flows affected by regulation at Slbralter and Junea1 Reservoirs.

Mean dally discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

796

172

1,490

2,040

974

441

278

197

265

728

Mar.

2,800

17,910

9,140

4,210

3,250

2,470

2,940

3,280

2,520

2,180

Apr.

535

509

488

463

473

428

400

380

366

356

Day

11

12

13

14

15

16

17

18

19

20

Feb.

9,700

3,400

1,660

1,250

1,010

766

591

491

496

478

Mar.

2,130

9,180

6,120

4,120

3,190

2,380

1,920

1,600

1,390

1,260

Apr.

343

343

348

325

309

289

281

266

254

242

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

386

356

331

335

294

269

254

421

1,067

59,240

Mar.

1,170

1,030

958

894

810

750

715

679

644

600

572

2 QQA

184,100

Apr.

224

214

203

217

277

250

200

183

193

193

-I! 0

18,950

Page height, in feet, and discharge, in second-feet, at indicated time, 1958

53

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet) Sec. ft.

February 27

Feet | Sec. ft.

February 28

4.79

4.80

4.62

4.83

4.84

4.84

4.84

4.84

4.85

4.86

4.87

4.88

4.89

4.89

4.89

4.91

4.94

4.97

5.02

5.12

5.30

5.87

6.90

7.69

248

254

263

266

269

272

272

275

278

285

288

294

298

301

301

311

324

338

360

402

462

785

1,590

2.460

Feet Sec.ft.

March 1

8.02

8.20

8.66

8.34

8.04

7.82

8.04

8.74

9.14

8.98

8.59

8.32

7.99

7.82

7.64

7.46

7.34

7.20

7.09

7.01

6.90

6.87

6.85

6.84

2,908

3,180

3,960

3,430

2,980

2,690

3,010

4,110

4,840

4,540

3,860

3,430

2,910

2,660

2,420

2,200

2,060

1,900

1,790

1,700

1,590

1,550

1,540

1.510

Feet Sec.ft.

March 2

6.85

6.88

6.95

7.12

7.40

7.71

8.24

8.89

9.79

10.61

12.50

14.20

15.80

16.35

16.00

15.75

16.70

17.90

17.20

15.60

14.65

13.60

12.65

12.10

1,520

1,560

1,610

1,780

2,060

2,410

3,120

4,150

5,900

7,840

16,840

24,400

32,100

34,900

33,100

31,800

36,900

43,700

39,700

31,000

26,400

21,400

17,400

15,2pO

Feet Sec.ft.

March 3

11.69

11.40

11.44

11.70

11.34

11.12

10.74

10.54

10.54

10.56

10.40

10.30

10.19

10.14

10.04

9.94

9.80

9.60

9.56

9.49

9.36

9.30

9.20

9. OK

13,600

12,400

12,600

13,600

12,200

11,400

10,100

9,420

9,420

9,480

9,000

8,700

8,370

8,220

7,920

7,620

7,250

6,750

6,650

6,480

6,150

6,000

5,750

K r SRO

Feet | Sec. ft.

March 4

8.94

8.84

8.80

8.74

8.69

8.64

8.54

8.54

8.50

8.52

8.50

 8.42

8.34

8.34

8.30

8.30

8.30

8.25

8.24

8.22

8.18

8.15

8.14

A.1A

5,130

4,940

4,840

4,260

4,620

4,540

4,330

4,350

4,260

4,330

4,280

4,140

3,980

4,000

3,920

3,940

3,940

3,870

3,850

3,830

3,750

3,720

3,700

S -75(1
SANTA YNEZ RIVER BASIN 279

Santa Ynez River near Lompoo, Calif.

Location.- Water-stage recorder, lat. 34°38'30", long. 120°25'50n , near boundary of La 

Mission Vleja de la PurlsIma grant, at highway bridge, lj milee east of Lompoc, Santa 

Barbara County. Altitude, about 100 feet.

Drainage area.- Area, 790 square miles. Average altitude, 1,884 feet. Maximum altltude, 6,828 feet* Average slope, 28 percent. Length of main stream channel, 71 

miles. Average slope of main stream channel, 1.7 percent.

Page-height record.- Water-stage recorder graph except 9 p.m. Mar. 2 to 4:30 a.m. Mar. 3.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 5,050 second-feet and by float measurements below 37,600 second-feet; extended 

logarithmically to peak stage. Shifting-control corrections used throughout the 

period. Discharge estimated 9 p.m. Mar. 2 to 4:30 a.m. Mar. 3.

Maxima.- 1938: Discharge, 50,100 second-feet 4 a.m. Mar. 3 (gage height. 28.10 feet).

1906-18, 1925-37: Discharge, 41,800 second-feet Jan. 25, 1914 (gage height, 

13.0 feet, former site and datum).

Remarks.- Records good. The cities of Santa Barbara and Monteclto divert water above 

gage. Flood flows affected by regulation at Glbralter and Juncal Reservoirs. 

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

643

746

992

2,190

1,940

1,100

628

441

522

738

Mar.

2,590

8,150

24,760

7,050

4,160

3,180

2,670

2,960

3,050

2,980

Apr.

726

679

646

620

601

588

562

531

506

493

Day

11

12

13

14

15

16

17

18

19

20

Feb.

6,330

15,010

3,520

2,220

1,540

914

1,040

855

791

766

Mar.

2,970

4,890

6,620

4,740

3,830

3,430

2,420

2,210

2,010

1,970

Apr.

475

444

434

428

422

417

400

379

358

342

Day

21

22

23

24

25

26

27

28

29

30

31

Runoff, In acre-feet.. .......................................

Feb.

694

623

542

485

458

398

355

463

1,676

93,110

Mar.

1,680

1,460

1,190

1,150

1,090

1,020

955

895

858

812

774

3,501

215,300

Apr.

337

318

288

293

313

322

303

288

279

298

436

25,960

gage height, in feet, and discharge, in second-feet, at Indicated time, 1938

8»

1

2

3

4

5

6

7

S

9

10

11

M

1

2

3

4

5

6

7

8

9

10

11

K

Feet Sec. ft.

February 27

Feet Sec. ft.

February 28

12.10

12.09

12.09

12.09

12.09

12.09

12.08

12.08

12.08

12.08

12.08

12.08

12.08

12.08

12.08

12.08

12.08

12.09

12.15

12.17

12.35

13.70

14.50

15.44

339

334

334

334

334

329

324

324

324

324

324

324

324

324

310

300

290

285

295

280

355

1,180

1,740

2.610

Feet Sec.ft.

March 1

15.44

15.00

14.58

14.20

13.88

13.70

14.00

14.65

15.14

15.33

15.30

15.22

15.45

15.75

16.00

16.25

16.43

16.42

16.37

16.51

16.76

16.92

17.15

17.21

2,580

2,120

1,720

1,420

1,180

1,040

1,220

1,680

2,090

2,250

2,200

2,090

2,300

2,570

2,820

3,120

3,360

3,400

3,360

3,570

3,920

4,150

4,5PO

4,620

Feet Sec.ft.

March 2

i?.32

17.56

17.50

17.33

16.97

16.91

16.97

16.95

17.10

17.17

17.39

17.81

18.10

18.58

18.83

18.67

18.35

18.47

18.63

19.12

20.00

4,830

5,230

5,180

5,000

4,520

4,510

4,680

4,720

5,030

5,210

5,600

6,380

6,980

7,910

8,500

8,180

7,620

7,880

8,360

9,490

11,700

18,700

23,000

28.000

Feet | Sec.ft.

March 3

28.10

27.43

26.35

25.25

24.05

23.50

23.10

22.85

22.73

22.63

22.35

22.25

22.00

21.55

21.17

20.82

20.70

20.55

20.38

20.18

20.00

32,000

39,000

46,700

50,100

45,600

39,000

32,900

27,000

24,500

22,700

21,600

20,900

20,500

19,400

19,000

18,000

16,300

15,000

13,800

13,400

13,000

12,400

11,800

11.300

Feet Sec.ft.

March 4

20.05

19.85

19.60

19.40

19.20

18.90

18.20

17.50

17.13

16.80

16.50

11,300

10,600

9,900

9,350

8,600

8,100

6,720

5,920

5,560

5,270

4,960

454720 O - 42 - 19
280 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 

Santa Maria River Basin

Cuyama River near Santa Maria, Calif.

long. 120-16'45", in Suey grant, at

ay bridge, 3~mlles upstream from Alamos'Creek, and 10 miles northeast of Santa 

Maria, Santa Barbara County. Altitude, about 610 feet.

Drainage area.- Area, 902 square miles. Maximum altitude, 7,488 feet. Length of main 

stream channel, 76 miles.

Sage-height record.- Water-stage recorder graph except 6 a.m. Feb. 6 to Feb. 12 and 9 

a.m. Mar. 3 to Mar. 9. Maximum gage height determined from high-water marks in gage 

well.

Discharge record.- Stage-discharge relation defined by current-meter measurements be- 

'low 4,370 second-feet) extended logarithmically to peak discharge determined by

 lope-area method. Shifting-control corrections used through the period of record.

Discharge Feb. 6-12 and Mar. 3-9 based on comparable hydrograph of Huasna River

near Santa Maria.

.- 19381 DiBQharge, 17,300 teoond-feet 9 a.m. Mar. 3 (g*ge height, 16.6 feet). 

'929-371 Discharge, 5,220 second-feet Feb. 6, 1937 (gage height, 7.60 feet).

Remarks.- Records fair except those for Feb. 

diversions above station.

6-12 and Mar. 3-9, which are poor. No

Mean daily discharge, in second-feet, 1933

Dar

i

2

3

4

5

6

7

8

9

10

Feb.

73

48

326

157

134

115

100

94

200

428

Mar.

114

325

5,350

2,120

800

400

290

37B

290

220

Apr.

71

74

72

69

76

68

64

6C

59

66

Day

11

12

13

14

15

16

17

18

19

20

Feb.

2,92C

992

326

246

144

104

87

76

87

78

Mar.

220

962

1,24C

690

615

400

332

290

256

232

Apr.

56

58

62

62

58

65

51

49

47

44

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

74

71

68

68

66

64

64

72

260

14,440

Mar.

204

183

159

146

129

119

104

96

90

78

72

542

33,320

Apr.

43

39

38

51

69

64

51

46

58

57

57.6

3,430

Huasna River near Santa Maria, Calif.

Location.- Water-stage recorder, lat. 35°01'20", long. 120°19<20", in Suey grant, half a 

mile upstream from junction with Ouyama River, and 8 miles northeast of Santa Maria, 

Santa Barbara County. Altitude, about 600 feet.

Drainage area.- Area, 119 square miles. Average altitude, 1,371 feet. Maximum altitude, 3,186 feet. Average slope, 31 percent. Length of main stream channel, 22 

miles. Average slope of main stream channel, 22 percent.

Page-height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 1,080 second-feet; extended to peak discharge determined by slope-area method. 

Shifting-control corrections used throughout the period.

Maxima.- March 1938t Discharge, 1,190 second-feet 5 p.m. Mar. 2 (gage height, 4.47 

Feet).

1929-February 19381 Discharge, 11,400 second-feet 10*20 a.m. Feb. 11, 1938 

(gage height, 11.26 feet).

Remarks.- Records fair. No diversions above station.
SALTON SEA BASIN 281

Mean dally discharge, in second-feat, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

304

143

597

427

243

163

127

105

193

340

Mar.

271

546

910

615

427

334

377

490

334

264

Apr.

69

55

52

48

51

47

44

43

42

42

Day

11

12

13

14

16

16

17

18

19

20

Feb.

4,630

986

493

552

395

306

240

218

252

173

Mar.

261

929

1,156

640

467

363

295

243

212

190

Apr.

.40

39

39

36

36

35

33

32

30

30

Day

21

22

23

24

35

26

27

28

29

30

31

Feb.

147

123

101

87

74

64

59

78

415

23,050

Mar.

169

157

139

135

121

111

97

89

83

72

64

341

20,950

Apr.

28

26

25

38

40

36

30

30

35

35

38.2

2,270

Page height, In feet, and discharge, 'In second-feet, at Indicated time, 1938

I

1

2

3

4

6

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec.ft.

February 27

Feet Sec.ft.

February 28

>1.71

1.72

1.73

1.75

1.75

1.82

2.88

2.85

> 59

62

63

66

66

77

344

334

Feet | Sec. ft.

March 1

2.73

3.02

2.95

2. 98

2. 89

2.84

2.80

2.75

2.70

2.65

2.59

2.58

2.54

2.52

2.50

2.47

2.45

2.44

2.41

2.39

2.37

2.35

2.36

2.35

292

399

375

391

359

341

327

310

292

276

258

255

243

237

231

222

218

215

208

202

198

192

195

192

Feet Sec.ft.

March 2

2.35

2.39

2.41

2.41

2.40

2.44

2.50

2.52

2.51

2.55

2.87

3.20

3.35

3.78

4.15

4.32

4.47

4.24

4.14

3.92

3.79

3.68

3.60

3.60

192

202

208

208

205

215

231

237

234

246

352

484

552

765

982

1,090

1,190

1,050

982

850

776

720

680

680

Feet Sec.ft.

March 3

3.65

3.72

3.68

3.80

3.84

3.90

3.95

4.07

4.14

4.10

4.12

4.18

4.17

4.37

4.35

4.30

4.25

4.15

4.05

4.02

4.00

3.95

3.87

3.80

705

740

720

782

804

838

868

940

982

958

970

1,010

1,000

1,130

1,120

1,080

1,050

.988

928

910

898

868

82Q

782

Feet Sec.ft.

March 4

Salton Sea Basin

Palm Canyon Creek near Palm Springs, Calif.

Location.- Water-stage recorder, lat. 33*44'55", long. 116°32'15N , In Si sec. 11, T. 

5 S., R. 4 E., three-quarters of a mile upstream from Murray Oanyon Oreek, and 6 

miles south of Palm Springs post office. Altitude, about 700 feet.

Drainage area.- 94 square miles.

Page-height record.- Water-stage recorder graph except Mar. 15-30.

Discharge record.- Stage-discharge relation fairly veil defined below 30 second-feet; 

extended above by mean velocity-mean depth relation. Discharge Mar. 15-30 obtained 

by comparison with Mill Creek near Craftonvllle and Santa Ana River near Mentone.

Maxima.- 1938: Discharge, 2,380 second-feet 10 p.m. Mar. 2 (gage height, 4.43 feet). 

1930-37: Discharge, 3,850 second-feet Feb. 6, 1937 (gage height, 5.60 feet).

Remarks.- Records good. No regulation or diversion above gage.
282 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Mean daily discharge. In second-feat, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

12

6.5

3.9

11

11

5.5

4.2

3.6

4.5

5.5

Mar.

106

731

813

224

77

50

41

38

31

26

Apr.

15

15

15

15

14

13

13

12

12

12

Day

11

12

13

14

15

15

17

18

19

20

Feb.

5.5

10

6

4.8

4.5

4.5

3.9

3.3

4.2

3.6

Mar.

16

125

82

34

26

22

20

19

18

17

Apr.

12

12

14

15

13

13

12

11

11

10

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

3.1

2.8

2.6

2.6

2.4

2.4

9

22

5

QQ

327

liar.

16

16

16

16

16

16

16

16

16

16

16

86.8

5,340

Apr.

10

10

9.5

9.5

13

13

10

9.5

9.5

9.5

2.2 1

719

Discharge, in second-feet, at Indicated tims, 1938

Hour

1

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

 9

10

11

H

March 1

19

21

30

100

248

238

202

183

175

148

130

123

112

100

95

89

84

77

72

69

66

62

59

58

March 2

56

55

54

54

56

64

70

86

150

366

491

533

658

616

501

599

741

1,012

1,900

2,200

2,210

2,380

1,840

1,460

March 3

1,120

1,000

936

825

754

721

862

1,050

1,080

1,260

1,110

1,000

862

804

754

664

628

570

544

528

522

496

470

440

Mojave River Basin

Deep Creek near Hesperla, Calif.

Location.- Water-stage recorder, lat. 34°20'30", long. 117°13'40", in SEi sec. 18, T. 

3 N., R. 3 W., naif a mile upstream from confluence with West Fork of Mojave River, 

and 8 miles southeast of Hesperia. Altitude, about 3,050 feet.

Drainage area.- Arsa, 137 square miles. Average altitude, 5,850 feet. Maximum altitude, 8,5OO feet. Average slope, 38 percent. Length of main stream channel, 21.6 

miles. Average slope of main stream channel, 4.5 percent.

Page-height record.- No record.

Discharge record.- Discharge Feb. 1 to Apr. 20 computed on basis of discharge measurements and studies of flow at other stations ia the Mojave River Basin; April 21-30 

by standard methods at temporary station a quarter of a mile downstream. Maximum 

discharge determined by slope-area method.

Maxima.- 1938: Discharge, 46,600 second-feet liar. 2.

1929-37: Discharge, 7,900 second-feet Feb. 9, 1932.

Remarks.- Records poor. Storage in Lake Arrowhead. No diversion during flood period.
MOJAVE RIVER BASIN 283

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

100

340

530

1,230

370

160

60

40

250

265

Mar.

2,850

12,000

5,700

1,900

1,200

880

740

600

550

530

Apr.

240

240

260

290

305

290

250

235

240

235

Day

11

12

13

14

15

16

17

18

19

20

Feb.

730

560

295

190

160

98

52

38

155

74

Mar.

550

2,200

2,700

2,100

1,600

1,550

1,375

1,210

960

850

Apr.

225

215

240

235

240

380

360

300

280

260

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

50

43

41

36

30

30

490

3,100

18,880

Mar.

760

620

510

430

420

420

380

350

350

300

300

93,000

Apr.

235

218

190

178

250

278

191

155

159

167

14,560

Mojave River at lower narrows, near Vlctorvllle, Calif.

Location.- Water-stage recorder, lat. 34034'25n , long. 117°19'10", In SWjSEi sec. 29, 

T. 6 N., R. 4 W., 500 feet upstream from bridge on U. S. Highway No. 66, and 3 miles 

northwest of Vlctorvllle. Altitude, about 2,640 feet.

Drainage area.- 530 square milea. . 

Page-height record.- Water-stage recorder graph except 7:30 p.m. Mar. 2 to Mar. 29.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 10,300 second-feet; peak discharge determined by slope-area method. Discharge 

Mar. 2-29 determined from discharge measurements and studies of flow at other stations In the Mojave River Basin.

Maxima.- 1938: Discharge, 70,600 second-feet 7:30 p.m. Mar. 2 (gage height, 16.70 

feet).

1930-37: Discharge, 12,500 second-feet Feb. 9, 1932.

Remarks.- Records fair except those for Mar. 2-29, which are poor. Storage at Lake 

Arrowhead and Lake Gregory. Ho diversions during flood.

Mean dally discharge, In second-feet, 1958

Day

1

2

3

4

5

6

7

8

9

10

Feb.

47

48

50

48

50

48

49

52

50

53

Mar.

4,350

 16,000

10,000

3,000

1,800

1,300

1,100

960

850

800

Apr.

330

330

365

403

440

416

342

319

330

309

Day

11

12

13

14

15

16

17

18

19

20

Feb.

54

288

166

120

102

90

75

64

73

107

Mar.

780

3,000

4,200

3,400

2,400

2,200

2,050

1,850

1,400

1,200

Apr.

297

285

330

319

323

405

376

303

271

271

Day

21

22

23

24

25

26

27

28

29

30

31

Runoff , In acre-feet . .........................................

Feb.

77

64

60

61

57

55

65

2,660

169

9,390

Mar.

1,050

890

760

620

580

530

485

430

410

354

354

2

0OQ

137,100

Apr.

245

221

187

176

226

360

303

215

159

209

17,980
264 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

sec. 51, 

about 2,090 feet.

Mo Java River at Barstow, Calif.

Location.- Water-stage recorder, lat. 34°54'25", long. 1170 01'2011 , In 

 T. 10 N. , R. 1 W., on U. S. Highway No. 91 at Barstow. Altitude,

Page -height record.- Water-stage recorder graph.

Discharge record.- Stage-discharge relation defined by current-meter measurements below 

5,200 second-feet; extended to peak discharge determined by slope-area method. Discharge Mar. 4-11, 20-31 determined from discharge measurements and studies of flow 

at other stations In the Mojave River Basin. Discharge for Apr. 1-30 determined by 

Interpolation between measurements.

Maxima.- 19381 Discharge, 64,300 second-feet 2 a.m. Mar. 3 (gage height, 8.60 feet). 

1930-37t Discharge, 8,300 second-feet Feb. 9, 1932.

Remarks . - Records fair. Storage at Lake Arrowhead and Lake Gregory. No diversions 

during flood.

Mean dally discharge, In second-feet, 1938

Day

1

2

3

4

5

6

7

8

9

10

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

3,070

3,720

18,100

3,200

1,850

1,250

1,050

920

820

770

Apr.

290

285

280

275

270

265

260

255

250

245

Day

11

12

13

14

15

16

17

18

19

20

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

730

1,600

4,000

3,500

2,240

2,060

1,890

1,920

1,350

1,140

Apr.

240

236

232

228

224

220

216

212

208

204

Day

21

22

23

24

25

26

27

28

29

30

31

Feb.

0

0

0

0

0

0

0

0

0

0

Mar.

900

757

680

580

520

460

410

360

340

320

300

1,962

120,600

Apr.

200

197

198

199

200

201

202

203

204

205

13,690

Page height, In feet, and discharge, In second-feet, at Indicated time, 1958

h

w

l

2

3

4

5

6

7

8

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet | Sec. ft.

February 27

Feet Sec. ft.

February 28

Feet Sec.ft.

March 1

2.50

2.65

2.90

2.90

3.13

3.05

3.25

3.22

3.05

3.15

3.17

3.15

3.10

3.25

3.55

3.90

4.15

4.25

4.35

4.13

3.95

3.89

3.85

3.75

415

610

1,070

1,070

1,650

1,430

2,020

1,920

1,430

1,700

1,760

1,700

1,560

2,020

3,200

5,000

6,600

6,800

7,710

6,320

5,400

5,100

4,950

4,450

Feet Seo.ft.

March 2

3.67

3.50

3.55

3.45

3.35

3.35

3.37

3.32

3.34

3.27

3.18

3.20

3.37

3.30

3.40

3.40

3.50

3.65

3.64

3.55

3.70

4.00

4.35

4.90

4,050

3,250

3,500

3,040

2,680

2,680

2,760

2,600

2,680

2,400

2,120

2,190

2,840

2,600

3,000

3,040

3,500

4,300

4,250

3,850

4,600

6,480

8,480

12,600

Feet Sec.ft.

March 3

6.65

8.60

7.90

7.00

6.45

5.95

5.65

5.45

' 5.40

5.35

5.25

5.08

4.91

4.75

4.60

4.45

4.34

4.22

4.11

4.00

3.90

3.83

3.80

3.75

31,800

64,300

50,800

36,800

29,400

23,000

19,700

17,700

17,200

16,700

15,800

14,200

12,700

11,400

10,300

9,250

8,480

7,640

6,870

6,200

5,700

5,350

5,200

4.950

Feet | Sec. ft.

March 4
MOJAVE RIVER BASIN 886

West Fork of Mojave River near Eesperia, Oalif.

Looation.- Water-stage recorder, lat. 34°20 t 20w , long. 117°14 t 3511 , In SBj sec. 13, T. 

3H77 R. 4 W. , at highway bridge, half a mile upstream from confluence with Deep 

Oreek, and 7 miles southeast of Hsaperia. Altitude, about 3,050 fset.

Drainage yea.- Area, 74.6 square miles.

tune, 6,150 feet. Length of main stream channel, 12.5 miles, 

strsam channel, 3.7 percent.

Average altitude, 4,270 feet. Maximum altiAverage slope of main

Gage-height record.- Water-stage recorder graph except 11 a.m. Mar. 2 to Mar. 14.

Discharge record.- Stags-discharge relation defined by current-meter measurements below 

8,060 second-feet; extended logarithmically to maximum discharge determined by 

slope-area method. Discharge for period of missing gage-height record determined 

from discharge measurements and studies of flow at other stations In the Mojave 

River Basin.

Maxima.- 1938s .Discharge, 26,100 second-feet Mar. 2.

1930-37: Discharge, 6,000 second-feet Feb. 8, 1932.

Remarks.- Records good except those for Mar. 2-14, which are poor. Storage at Lake 

Gregory.

Mean daily discharge, in second-feet, 1938

Day

1

2

3

4

5

6

7

6

9

10

Feb.

67

197

287

603

212

106

71

54

151

160

Mar.

2,090

7,000

3,300

1,100

700

520

410

360

330

310

Apr.

178

164

161

158

164

147

126

125

114

111

Day

11

12

13

14

15

16

17

16

19

20

Feb. 37~5

298

174

122

103

89

67

52

106

79

Mar.

330

1,300

1,600

1,200

844

740

660

560

480

429

Apr.

106

102

150

114

108

102

98

91

78

88

Day

21

22

23

24

25

26

27

26

29

30

31

Feb.

64

56

56

50

43

43

264

1,410

1 Q9

10,640

Mar.

366

324

275

235

232

232

214

201

201

187

187

pry ft

53,470

Apr.

74

74

70

67

171 

128

102

66

90

174

IIP

7,000

Gage height, in feet, and discharge, in second-feet, at indicated time, 1936

I

1

2

3

4

5

6

7

6

9

10

11

N

1

2

3

4

5

6

7

8

9

10

11

M

Feet Sec. ft.

February 27

0.87

.87

.87

.95

1.03

1.12

1.28

1.57

1.85

2.20

2.65

3.00

3.27

3.30

3.32

3.35

3.30

3.25

43

43

43

52

62

74

98

148

208

298

446

582

695

715

730

745

725

705

Feet Sec. ft.

February 26

3.20

3.10

3.15

3.22

3.40

3.65

3.66

4.15

4.40

4.50

4.60

5.10

5.60

5.94

5.70

5.52

5.18

4.83

4.60

4.35

4.16

4.05

4.10

4.50

690

646

666

710

600

930

1,040

1,210

1,370

1,430

1,500

1,870

2,220

2,440

2,290

2,170

1,950

1,740

1,600

1,460

1,340

1,280

1,310

1,550

Feet Sec. ft.

March 1

6.00

7.75

8.70

9.33

8.20

6.75

6.00

5.70

5.43

5.15

4.85

4.67

4.47

4.36

4.25

4.15

4.05

3.95

3.85

3.75

3.65

3.60

3.55

3.50

2,480

3,780

4,540

5,050

4,130

3,020

2,460

2,290

2,120

1,940

1,750

1,650

1,530

1,470

1,400

1,340

1,260

1,220

1,170

1,120

1,070

1,040

1,010

' 990

Feet Sec. ft.

March 2

3.43

3.38

3.39

3.42

3.58

3.66

3.95

5.00

6.25

7.10

7.70

940

920

925

940

1,020

1,070

1,220

1,840

2,660

3,220

3,710

Feet Sec. ft.

March 3

Feet Sec. ft.

March 4
286 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA 

SUMMARY OF FLOOD DISCHARGES

In table 23, "Summary of flood discharges," are assembled the results of the determinations of maximum flood discharges at stream-gaging 

stations and other places on streams in southern California. For convenience, several gaging stations that are plotted on the isohyetal maps 

are included, although the maximum discharge at those stations was not 

determined. The table gives the following information: (l) Map reference 

number, to aid in locating the place where the discharge was determined, 

as plotted on plates 11, 12, and 13; (2) name of stream and place where 

discharge was determined; (3) latitude and longitude of place of measurement; (4) approximate 'altitude of place of measurement as determined from 

topographic maps; (5) drainage area, in square miles, tributary to the 

stream at the place where discharge was determined; (6) period of record 

which conforms to period of operation of the station given only for existing stream-gaging stations; (7) date and magnitude of the maximum 

discharge recorded prior to the March 1938 floods, that is, during the 

period of record given in the preceding column; (8) day and hour, if 

known, and rate in second-feet, total and per square mile, of the maximum 

discharge in March 1938; (9) a brief notation as to the method used in 

determining the maximum discharge.

Water-Supply Papers 391 (pp. 89-91) and 447 (pp. 544-550) give, 

among other data, tables of estimated flood discharge of streams in the 

vicinity of Los Angeles, Calif., during the storms of January and Febru-r 

ary 1914. At that time, under the direction of J. B. Lippincott, of the 

board of engineers for flood control, Los Angeles County, sections were 

selected and data collected for computing flood flow. The summary of 

flood discharges as given in this report (table 23) is primarily concerned with records made since continuous and systematic stream-gaging 

was inaugurated, and therefore the estimates of flood discharge from the 

storms of January and February 1914 were not generally considered in the 

preparation of the table. A summary of information concerning floods 

prior to the general period of record is given in the section of this report on "History of floods in southern California". (See pp. 385-394.)

The methods employed are described in detail in the section of this 

report entitled "Determination of flood discharge". (See pp. 168-182.) 

The basic data used in determining the discharges are filed in the Los 

Angeles office of the Geological Survey, where they may be examined.
SUMMARY OF FLOOD DISCHARGES 887

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288 FLOODS OF MARCH 1938 ITS SOUTHERN CALIFORNIA

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22

23

24

25

26

27

28

29

30

31

32

33

34

Arroyo San Onofre Basin

Arroyo San Onofre near San

Onofre

San Juan Creek Basin

San Juan Creek near San

Juan Capistrano Jfe/

Tratuco Creek near San

Juan Capistrano si/

Aliso Creek Basin

Aliso Creek at Si Toro £/

Lacuna Oreok Basin

Laguna Creek at Laguna

Beaoh

Santa ^3& ^iver Basin

Santa Ana Biver near Hentone

Santa Ana Biver at Riverside Harrows, near

Arlington

Santa Ana Biver near Frado

Santa Ana River at Santa

Ana

Bear Creek, inflow to Bear

Valley Reservoir near

Pine Knot Jfe/

Mill Creek near Craftonville

Plunge Creek near East

Highlands

San Tlmoteo Creek near

Badlands -

33 23 20

33 30 50

33 31 30

33 37 15

33 32 40

34 06 40

33 58 00

33 52 05

33 45 00

34 14 30

34 05 15

34 07 10

34 01 55

117 32 50

117 37 40

117 40 15

117 41 20

117 47 00

117 06 00

117 26 30

117 40 20

117 54 20

116 58 35

117 02 25

117 08 30

117 12 30

100

150

200

440

25

1,900

690

400

80

6,700

2,950

1,625

1,260

39.8

110

36.5

8.5

8.8

d 144

845

el, 520

-

42.2

42.9

16.9

118

^

1929-38

1930-38

1930-38

_

1896-

1938

1929-38

1919-38

1923-38

_

1919-38

1919-38

1926-38

Feb. 6, 1937

Feb. 6, 1937

Feb. 6, 1937

_

Jan.27, 1916

Feb. 7, 1937

Feb.16, 1927

Feb.16, 1927

-

Feb.16, 1927

Feb.16, 1927

Feb. 6, 1937

1

1

2

a Occurred Mar. 3. 1

b Records furnished by Corps of Engineers, U. S. Army.

o Beoords furnished by Orange County Flood Control District.

d Ex

e Ex
290 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

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52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

San Jaointo Elver near

Elslnore

Elslnore Late at Elsinore

(inflow) Jj/

Temesoal Creek near Corona

Chino Creek near Chino

Chino Creek near Prado

San Antonio Creek near

Clarenont

San Antonio Creek near

Chino

Santiago Creek at Santiago

Reservoir, near Villa

Park (inflow) i/

Santiago Creek near Villa

Parki/

Santiago Creek at Santa Ana

Irvine Banoh drainage oanal

naar Tug tin &J

San Gabriel River Basin

East Fork of San Gabriel

Elver near Carap Bonita

San Gabriel Biver at floodcontrol reservoir So. 1,

near Azasa (inflow) £/

San Gabriel Biver at Morris

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Inflow i/

Outflow

San Gabriel Biver at Foothill Boulevard, near

Aznsa Ji/

33 39 45

33 40 35

33 50 30

33 56 50

33 53 40

34 12 50

34 01 35

33 47 00

33 49 10

33 48 00

33 40 50

34 14 15

34 12 15

34 10 25

34 08 15

117 17 45

117 21 30

117 30 45

117 40 05

117 38 40

117 40 00

117 43 40

117 43 35

117 46 30

117 52 45

117 51 30

117 49 10

117 51 20

117 52 50

117 56 35

1,270

1,200

730

530

460

3,400

760

680

420

120

26

1,500

1,200

950

580

717

798

g!57

88*2

176

16.9

36.7

62.5

83.8

-

93

91.4

202

211

230

1916-38

_

1929-38

-

1929-38

1917-38

-

-

1920-38

1929-38

1930-38

1932-38

.

-

1894-

1938

1932-38

Feb.17, 1927

-

Feb. 6, 1937

-

Jan. 1, 1934

Dec.19, 1921

-

-

Feb. 16, 1927

Feb. 6, 1937

Feb. 6, 1937

Jan. 1, 1934

-

-

Jan. 18, 1916

Jan.19, 1933

1

1

4

1

b Records furnished by Corps of Engineers, U. S. Army.

o Records furnished by Orange County Flood Control District.

f Occurred liar. 5.

g Area below EL

h Hecords furnis

i Records furnis
292 FLOODS OF MARCH 1938 IS SOUTHERN CALIFORNIA

d of nation

o 4» $ C

N M «

8800 tO

00 O

8* S

1 B.

Pk Pk

as

sso> o>

I &

o> o> l-l l-l

ft t- fl II'

<W 0

hog

o 5

CM CM 

O> O>

t- in to

"S S

§ tO 00i

ft l-l

in CM

8 81 9 8

O O 115

00 00 SSfl S

tO O

w o

l£) O*

IO in

§§ 9

8§ 3 

SB S

S

ICJ 

M

S S S

n i

place and rmination

'* . ^*^.

"

oj rt It O 

C5 O

4f>llfp*f

Jjrs*$a*» <Hp5fj<api-ifi

M M 3 rH tsq fi 8

O 44 VI O *4 O W

i-ii-jfio fcgo £

O O +> ««H fi 4* O

^ H «« £« O »H i! «J rH

hh+>h >CCjh O

I +> -rt 

I R OJ .H H0»«

W CO f ______5; 

e- oo o> o

b -e £* !

00 Cy ® F3

<D ta >rt

000*1^0

on "^* ® 

0) - « h <D h

o o h 2 o

a e

*> 4J g *> 

 H Pi R «H <

CM*

'S "8 ^

s^l i S ra 83 SSil
80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

West Fork of San Dimas

Greek near San Dimas jj/

Dalton Greek at floodcontrol reservoir near

Glendora (inflow) h/

Dalton Creek near Glendora

Little Dalton Creek near

Glendora &/

Walnut Creek near Baldwin

Park h/

Live Oak Creek at floodcontrol reservoir near

La Verne (inflow) ,h/

San Jose Creek near Whittier h/

Thompson Creek at floodcontrol reservoir near

Claremont (inflow) h/

Coyote Creek near Artesia Jj/ ,h/

Brea Creek at Full art on £/

Carbon Creek at Olinda $J

Los Angeles River Basin

Los Angeles River near Van

Buys h/

Los Angeles River near

Universal City Jj/ h/

Los Angeles River at Los

Angeles i/

Los Angeles River near

Downey ,h/

Los Angeles River at Long

Beaoh h/

34 10 10

34 10 10

34 09 20

34 09 30

34 03 55

34 07 45

34 01 25

34 08 30

33 50 46

%

33 52 25

33 53 20

34 09 30

34 08 35

34 04 50

33 56 45

33 47 25

117 46 15

117 48 30

117 49 50

117 50 15

117 59 00

117 44 45

118 02 05

117 42 30

118 03 30

117 55 40

117 50 40

118 26 55

118 22 10

118 13 35

118 10 25

118 12 20

1,600

1,565

1,150

1,110

335

1,430

230

1,582

35

250

352

636

550

298

88

-

1.66

4.49

7.5

3.3

99

2.30

85.2

3.91

110

26.4

20.0

157

_

510

614

_

 .

1929-38

1919-38

1929-38

1928-38

1936-38

1929-38

1932-38

1929-38

1930-38

1930-38

1928-38

1930-38

1989-38

1928-38

1928-38

_

Jan. 1, 1934

February 1914

February 1914

Jan. 1, 1934

Feb. 6, 1937

Jan. 1, 1934

Feb. 9, 1932

Feb. 6, 1937

Oct. 17, 1934

Jan. 1, 1934

Jan. 1, 1934

Jan. 1, 1934

Jan. 1, 1934

Jan. 1, 1934

Feb. 14, 1937

j 

1

1

8

3 

13

4

1

7

9

22

29

20

b Records furnished by Corps of Engineers, U. S. Arny. 

c Records furnished by Orange County Flood Control District* 

h Records furnished by Los Angeles County Flood Control District.
table 23.- amaaary of flood dischargee Con

So. 

on nap 

(pl.ll. 

12, 13)

96

97

98

99

100

101

102

103

104

106

106

107

108

Stream and place 

of determination

PACIFIC SLOPS BASHTS Con.

Lqa, Ancelea Blver Baai,n 

Con.

Browns Oreek at Ohatsworth

h/

Paooima Oreek at floodoontrol reservoir near

San Fernando (inflow) i/

Paooima Oreek near San

Fernando h/

Paooima Creek at Mission

Acres Jt/ ]}/

Tujunga Oreek near Colby

Banch Jt/

Tujunga Creek at floodcontrol reservoir near

Sunland (inflow) j]/

Tujunga Creek near Sunland Ji/

Tujunga Oreek near San

Fernando .b/ h/

Wttle Tujunga Oreek near

San Fernando Jj/

Halnes Oreek near Tujunga

Terdugo Oreek at Del Tall*

Avenue, Glendale Jj/ J]/

Terdugo Oreek at GlendaleJ/

Arroyo Seoo near Pasadena

latitude

0 t ft

34 16 26

34 20 00

34 20 02

34 13 40 *

34 18 10

34 17 30

34 17 55

34 16 60

34 16 30

34 15 50

34 11 06

34 09 26

34 13 20

longitude

0 1 if

118 36 46

118 23 46

118 23 56

118 27 30

118 09 36

118 11 10

118 16 10

118 22 50

118 22 20

118 16 15

118 13 36

118 16 26

US 10 40

Altitude

1,100

1,650

1,650

820

2,450

2,104

1,600

995

1,260

2,200

915

465

1,400

Drainage 

area

( 0..

ml.)

14.3

27.8

27.9

50.6

66.9

81.4

106

148

21.0

1.2

19.1

22.4

16.4

Period 

of 

record

1929-32

1936-38

1927-38

1916-38

1929-38

1930-38

1931-38

1916-38

1931-38

1928-38

1917-38

1936-38

1936-38

1910-38

Maximum discha

previously kno

Date

Feb. 9, 1932

Jan. 1, 1934

February 1914

Feb. 8, 1932

Feb. 8, 1932

Jan. 1, 1934

Deo.l», 19X1

Jan. 1, 1934

Jan. 1, 1934

Jan. 1, 1934

.

Jan. 5, 1935

Uar.30, 1936

Feb.20, 1914

J
109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

Arroyo Seco at Devils Gate

Dam, near Pasadena (inflow) v

Santa Anita Creek near

Sierra Madre

Santa Anita Creek at floodoontrol reservoir near

Sierra Madre (inflow) V

Little Santa Anita Creek

near Sierra Madre

Little Santa Anita Creek at

flood-control reservoir

near Sierra Madre (inflow) .h/

Eaton Oreek near Pasadena

Baton Creek at floodcontrol reservoir near

Pasadena (inflow) V

Baton Creek near £1 Uontej/

Hubio Canyon Wash at Rpsemesd Taf

Alhambra Wash at Alhambra

Rio Hondo near El Monte

Jj/ ~bl

Rio Hondo near MontebelloJ^

Rio Hondo near Downey Jj/

Bpllnno CrQBk Basin

Centinela Creek near Culver

CltyVV

Ballona Oreek near Culver

Oity V V

Benedict Canyon storm drain

at Culver City V 4/

34 11 10

34 11 45

34 11 10

34 11 15

34 10 40

34 11 40

34 10 05

34 05 15

34 04 30

34 03 20

34 05 36

34 01 55

33 56 40

33 58 35

33 59 50

34 01 23

118 10 30

118 01 05

118 01 10

118 02 35

118 02 40

118 06 15

118 05 30

118 03 55

118 04 35

118 05 10

1J.8 01 55

118 04 15

118 09 50

118 23 05

118 24 10

118 23 00

1,000

1,400

1,100

2,200

1,110

1,230

840

288

290

244

295

200

95

47

40

95

30.6

10.5

10.8

1.9

2.39

6.5

9.48

18.4

13.4

14.5

-

_.

-

5.17

112

6.96

_

1916-38

1932-38

1916-36

-

1918-38

_

1930-38

1930-38

1930-38

1932-38

1928-38

1928-38

1932-38

1928-38

1935-38

February 1914

Apr. 7, 1926

Jan. 1, 1934

Apr. 7, 1926

-

Apr. 7, 1926

.

Jan. 1, 1934

Dec. 31, 193!$

Jan. 1, 1934

Jan. 1, 1934

Jan. 1, 1934

February 1914

liar. 2, 1935

Jan. 1, 1934

Feb.12, 1936

1

1

2

1

a Occurred Mar. 3.

b Records furnished by Corjs of Engineers, U. S. Amy.

h Records furnished by Los Ang

J Mean for 1 hour.
Table 23. Summary Of flood discharges Continue

No* 

on map 

(pl.ll. 

12, 13)

125

126

127

128

129

130

131

132

133

134

135

136

i

Stream and place 

of determination

PACIFIC SLOPE BASINS Con.

Topanga Creek Basin

Topanga Creek near Topanga

Beaoh b/

Malibu Creek Basin

Malibu Creek at Crater Camp

near Calabasas «b/

Oalleguas Creek Basin

Calleguas Creek near Oanarlllo

Happy Oarnp Creek at Moorepark

Arroyo Oonejo near Oamarillo

Honda Barranca at Berylwood

Boad, near Somia n/

Honda Barranca at Perking

Boad, near Somia a/

Santa Clara Biver Basin

Santa Clara River near

Ravenna

Santa Clara River near

Saugus b/

Santa Clara Kiver near

Santa Paula

Agua Duloe Creek near Lang

Sand Creek near long

Latitude

0 t it

34 03 50

34 04 30

34 10 40

34 17 10

34 12 15

34 17 22

34 16 05

34 26 20

34 25 42

34 19 40

34 26 30

34 23 20

Longitude

c » « 

118 35 10

118 42 10

119 02 30

118 51 30

118 55 00

119 02 32

119 02 55

118 18 35

118 35 23

119 04 36

118 19 55

118 25 05

Altitude

270

460

55

590

460

562

349

2,030

_

210

1*960

1,755

Drainage 

area 

(s%.

mi.)

17.9

103

249

12.0

35.1

1.35

2.86

116

355

1,533

29.5

7.4

Period 

of 

record

1930-38

1931-38

_

-

_

.

_

1929-38

-

_

-

Maximum dlsobarge 

previously known

Date

Dec. 31, 1933

Jan. 1, 1934

_

-

_

-

_

Jan. 1, 1934

-

_

-

Sec

ft

4,5

9,6

_

-

_

_

_

3,8

-

-
137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

Bouquet Creek near Saugus

San Franoiiqnito Cnwsc near

Castaio Creek near Castaio

San Hart Inez Chiquito Creek

near Del Valle

Piru Creek near Piru

Pole Creek at Fillmore

Sespe Creek near Fillmore

Santa Paula Creek near

Santa Paula

Adams Creek near Santa

Paula

7/heeler Creek near Santa

Paula

Aliso Creek near Santa

Paula

Harraon Creek near Saticoy

Hall Creek Basin

Hall Creek at Ventura

Ventura River Basin

Matilija Creek at Matilija

Ventura Hiver near Ventura

Senor Creek near Ojai

San Antonio Creek near Ojai

Gridley Creek near Ojai

Coyote Creek near Ventura

Santa Ana Creek near OakCanada del Diablo near

Ventura

34 31 55

34 31 15

34 32 40

34 25 05

34 25 30

34 24 30

34 26 55

34 23 40

34 20 40

34 20 05

34 19 45

34 17 30

34 16 40

34 29 05

34 20 55

34 28 10

34 25 25

34 28 05

34 21 20

34 23 45

34 18 35

118 26 25

118 31 55

118 37 40

118 39 25

118 45 45

118 54 25

118 55 35

119 04 35

119 06 10

119 08 25

119 09 10

119 11 55

119 15 50

119 18 30

119 18 20

119 12 05

119 15 30

119 12 20

119 18 50

119 20 25

119 19 05

1,990

1,490

830

930

780

630

590

650

310

335

340

450

110

970

210

1,150

580

1,100

250

435

205

q 21.2

40.5

77.7

4.8

432

7.8

254

39.8

8.4

8.0

12.5

3.4

5.4

55

187

5.7

33.9

3.6

41.1

11.3

4.7

_

-

_

-

1911-13

1927-38

_

1927-38

1927-38

-

-

_

-

-

1927-38

1911-13

1929-36

-

-

-

1927-32

1933-38

-

_

_

-

_

-

Feb. 9, 1932

..

Deo.31, 1933

Deo.31, 1933

-

-

^

-

-

Deo.31, 1933

Deo.31, 1933

-

-

-

Feb. 14, 1937

-

15,

84.

10.

7,

23,

5

h Beoords furnished by Los Angeles County Flood Control District. 

a Becords furnished by U. S. Soil Conservation Service. 
298 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

It Det fl « 

0 0

-H 0s)

. *

O 4* 0

8 5 A

o o

«3 in

 » » 

CD tO CO to to *

O O

o o

1 i i

CM «D «*

. »

a s

 

Q *>

M **

S 8 O» CO

 g n

r-l r-l iH r-l

«

3!

O O

o o

10 O

51 «

r-l ON 10

go

« CM 

r-l r-l

8 8

r.s
166

167

168

169

170

171

172

173

THE GRfiiT BASQT

Salton Sea Basin

Whitewater Elver above

Whitewater

Whitewater Eiver near

Indian Wells

San Sorgonio" River near

Banning

Palm Canyon Creek near

Palm Springs

Mojave Eiver Basin

Deep Creek near Hesperla

Mojave Elver at lower

narrows, near Victorville

Mojave River at Baratow

WesC ForX of Mojave Eiver

near Hesperia

33 58 55

33 42 55

%

33 67 05

33 44 55

34 20 30

34 34 25

34 54 25

34 20 20

116 39 20

116 18 20

116 52 45

116 32 15

117 13 40

117 19 10

117 01 20

117 14 35

2,100

85

2,740

700

3,050

2,640

2,090

3,050

51.4

526

21.2

94

137

530

_

74.8

^

_

_

1930-38

1929-38

1930-38

1930-38

1930-38

_

-

Feb. 6, 1937

Feb. 9, 1932

Feb. 9, 1932

Feb. 9, 1932

Feb. 8, 1932

3,

7,

12,

8,

6,

a Occurred Mar. 3. t Mean for 1

j Mean for 1 hour. u Slope-area 

r Records furnished by Montecito County Water District. v Occurred M

s Records furnished by City of Santa Barbara. 
300 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF

By Harold V. P'eterson

Introduction

In a region in which the structures are as diverse and the topographic and geologic contrasts as sharp as they are in southern California 

it is evident that any attempt to discuss the relation between flood runoff and the physiographic and geologic features on an areal basis, must 

be a generalization. Stream flow resulting from rain falling on a drainage basin represents the combined influence of many factors, chief among 

which are distribution, rate, and amount of rainfall, antecedent rain, 

climate, shape of the drainage area, condition of the channel, and the 

ability of the surface mantle and underlying bedrock to absorb and to retain the rain. Geology has an important bearing on the last-named factor, 

because the type and texture of the surface mantle and the character and 

structure of the underlying bedrock are the result of geologic agencies 

and processes. Soil conditions often determine the type and extent of 

vegetal covering, which has an important influence on the rainfall-runoff 

relation, although the climate of the region has a far-reaching influence 

on this relation as well as on stream development.

As rain falls on^the surface of the ground, it is disposed of in 

three ways: it may be evaporated, it may be absorbed by the soil mantle, 

or it nay run off as surface flow. Of the rain that becomes runoff from 

any particular area, a part may evaporate from the open water surface and 

the remainder may flow by devious routes to the ultimate drainage channel 

or be partly or entirely absorbed into available subsurface storage along 

the route. The storage capacity of the surface mantle and the underlying 

formations and the rate at which absorption will take place are factors 

that affect the rainfall-runoff relation. Both are largely determined by 

the geologic characteristics of the drainage basin. Runoff studies of 

many southern California streams indicate that geologic features exert 

considerable influence on both ordinary and flood flows, and no doubt 

most of the other streams of the region also, are affected by the geology 

of their drainage basins, although the relationship is not so obvious nor 

so easily recognized.

The southern California region consists of a series of mountain 

ranges representing great upfaulted or upfolded blocks of the earth's 

crust. The intervening valleys occupy depressed segments filled with
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 301

debris eroded from the surrounding mountains. Surface features affecting 

runoff throughout this region range from steep outcrops of practically 

impervious unweathered rock to almost level surfaces underlain by thick 

deposits of highly permeable alluvium. In areas of the first type practically all the rain that falls will become runoff, but in areas of the 

second type the permeable material will absorb all the rain and prevent 

runoff. Between these extremes are gradations, which vary according to 

the topography, character of the surface mantle, and condition of the 

subsurface bedrock.

Physiographic features of the region are youthful in character. The 

steep mountain ranges rise abruptly from the relatively flat valleys. 

Streams within the mountain area occupy deep V-shaped canyons separated 

by sharp narrow ridges. The canyon walls are, as a rule, extremely steep, 

their slope In many places being only slightly less than the angle of repose of the materials covering them. Mechanical weathering is the 

dominant factor in rock disintegration and is instrumental in maintaining 

the steep and rugged form of the mountain area. This process is constantly acting to supply loose material susceptible of being transported 

by stream action.

Erosion within this mountain area and deposition on the floors of 

the adjacent valleys are proceeding at an active rate. The great alluvial cones found at the mouths of practically all the canyons are products 

of these processes. Owing to the seasonal or cyclic character of the 

storxoa common to the region, erosion and deposition do not occur at regular intervals; instead, dry periods, during which many of the stream beds 

are being aggraded, alternate with flood periods, when great quantities 

of water transport the already disintegrated and loosened debris from the 

mountains to the valleys. This sharp contrast In both quantity of flow 

and debris load causes unstable channel conditions, especially over the 

cone area, with the result that streams often overflow and shift their 

positions during heavy storms. The recurrence of this shifting of the 

streams with its accompanying deposition of debris over a long period of 

year* has, of course, been responsible for the natural development of the 

oones.

The floors of the alluvium-filled valleys represent the flood plains. 

They consist of a wide expanse of nearly flat lands that merge into the 

gently sloping oones near the valley margin. The streams, as a rule, are 

not established in permanent courses but occupy shallow channels out In 

the aoft, unoonsolldated valley fill. In times of flood they overflow
302 FLOODS OF MARCH 1938 IK SOUTHERN CALIFORNIA

and spread, often forming new channels, with the partial or complete 

abandonment of the old. Wide shifting is known to have occurred on the 

Santa Ana, Los Angeles, and San Gabriel Rivers within historic times, and 

a repetition of this action is possible on these and other streams during 

any future major flood. Efforts to confine the streams are successful 

only to the limit of capacity of levees or other flood-control structures, 

and once their capacity is exceeded, as It was in many localities during 

the flood of March 1938, the flow is essentially uncontrolled.

Owing to the torrential nature of the storms common to the region, 

coupled with the unstable character of the stream beds and the low relief 

of the valley floors, floods in southern California are a greater potential source of damage than In areas where the stream channels and flood 

plains are well defined and. easily distinguished.

In the following discussion the purpose has been to outline briefly 

the main geologic features of the region and to point out what appear to 

be some of the relations between these features and the runoff from rainfall. Some of the relations seem well-defined and easily recognized, but 

others are indistinct or obscured by other factors. Neither the time nor 

the opportunity was available to make detailed field investigations on 

any phase of the subject, and as a consequence only general aspects of 

the relations are herein considered. Information covering the general 

geology of the region has been obtained largely from publications of the 

Geological Survey of the Department of the Interior, the Division of 

Water Resources of the State of California, and the University of California. Other reports and studies relating to the subject have been made 

available by the Los Angeles County Flood Control District. For convenience in discussion, the region has been divided Into districts, each of 

which is characterized by similarity of topographic and geologic features.

San Diego area 18

That part of western San Diego County extending from the crest of 

the main mountain range west to the Pacific Ocean and from the international boundary north to the Orange County line is naturally divided into 

two physiographic and topographic units. To the east lie the mountain 

highlands, and to the west the narrow coastal belt characterized by dissected terrace formations that terminate at the ocean in a line of sea 

cliffs. "

18 See also Ellis, A. J., and Lee, C. H., Geology and ground water 

of the western part of San Diego County, Calif.: U. S. Geol. Survey WaterSupply Paper 446, 1919.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 303 

Mountain highlands 19

The mountains of the San Diego area belong to the Peninsular Range, 

which extends southeast from the Santa Ana Range through the peninsula of 

Lower California. In the higher, eastern part the general altitude of 

the range is more than 3,000 feet above sea level; in the western part it 

is 500 to 1,500 feet above sea level. The highest peaks rise to altitudes 

of about 6,000 feet. The topography, as a rule, is that of a mature, 

eroded surface. Slopes are gentle to moderately steep, and the main 

streams have cut to or near a graded surface.

Within the mountain highlands are several broad valleys, the most 

notable being Cajon, Santa Maria, Green, Escondido, Poway, San Jose, and 

San Felipe Valleys. In general, each is partly or completely surrounded 

by hills or mountains, and their floors are level or gently rolling, occasionally broken by low hills or knobs of granite. Their isolated position and the remoteness of most of them from any large river channel 

indicate that these valleys were formerly a part of an old peneplained 

surface.

Some faulting has occurred within the mountain highlands. Two faults 

have been mapped by Ellis,^*"* both apparently southeast extensions of the 

Elsinore fault systems. One of these strikes southeast from the town of 

Temecula. The upper part of the San Luis Rey River, above the Pala Indian 

Reservation, follows the line of this fault. About 8 miles to the northeast a rather prominent northeastward-facing scarp extending from Fauba 

Valley to San Jose Valley marks the line of a second fault parallel to 

the first. The upper part of Temecula Creek flows along the course of 

this fault for a distance of about 15 miles. Farther west several lines 

of topographic expression indicate the presence of faults, but definite 

evidence of their existence is not available.

The broken character of the crystalline complex, which allowed pronounced weathering and deep disintegration, is undoubtedly due to strains 

in the earth's crust that were contemporary with faulting, but the sharp 

structural breaks between mountains and valleys and the gravel-filled 

troughs common to the San Bernardino and San Gabriel Ranges are not found 

in the San Diego area. Certain surface and subsurface conditions created

19 See also Sauer, Carl, Land forms in the Peninsular Range of California as developed about Warner's Hot Springs and Mesa Grander Calif. 

Univ., Pub. in Geography, vol. 3, no. 4, pp. 199-290, 1929; Miller, W. J., 

Geomorphology of the southern Peninsular Range of California: Geol. Soc. 

Am. Bull., vol. 46, pp. 1535-62, October 1935.

20 Ellis, A. J., and Lee, C. H., op. cit., pi. 3.
304 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

by faulting no doubt have some effect on the flood runoff, but definite, 

evidence of a relationship between the structural features and runoff is 

lacking.

Coastal belt

A narrow belt underlain by sedimentary rooks of Eocene age and 

younger follows the ooaat line and extends eastward a distance of 5 to 20 

miles. As previously noted, it consists largely of level or gently rolling broad-topped terraces dissected by streams. North of the Otay River 

these terraces slope toward the sea from an altitude of 500 feet along 

the eastern margin of the belt to 300 feet near the coast. South of the 

river they slope in the opposite direction and range in altitude from 550 

feet at the coast to 500 feet 4 miles inland. Structural deformation appears to be responsible for this contrast.

The terraces, locally called mesas, are capped by a shallow reddishbrown soil oontaining mixtures of partly weathered sand, gravel, and clay. 

The underlying formations consist of well-consolidated marine sediments, 

including sandstones, shales, and conglomerates. For the most part both 

the surface and subsurface deposits are rather tight and impervious, a 

condition that permits only a small amount of absorption and consequently 

a small yield of water from underground sources.

River valleys

The Tia Juana, Sweetwater, San Diego, San Dieguito, and San Luis Rey 

Rivers all head near the summit of the Peninsular Range and flow southwest 

or west to the ocean. The Otay River occupies a small basin that heads 

near Lyons Peak, which is several miles west of the main divide. The 

Santa Margarita River has out beyond the divide and drains a large area 

between the Santa Ana and San Jacinto Ranges.

As with other features of the San Diego area, the regimen of the 

streams has been controlled to a large extent by oscillation of the land. 

Within the mountain highlands the streams have out deep gorges with steep 

side slopes, but the valleys are generally wide and their floors are 

graded, indicating that at one time the land surface was considerably 

higher than at present. Subsequent sinking and filling on the valley 

floors resulted in the present conditions. The fill consists of alluvial 

deposits of sand, gravel, and clay, in which sand predominates. Within 

the coastal belt a similar condition prevails. The sides of the valley 

are steep, although comparatively low. The floors are wide and flat.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 305

Near the coast most of the streams are partly drowned, giving rise to 

marshy tidelands of considerable extent.

The valley fill ranges in thickness from a thin layer to more than 

100 feet. In some reaches of the canyons, especially in the higher mountain areas, the stream beds are narrow and the bedrock crops out at the 

surface. Commonly, however, the valleys are wider both above and below 

the canyons and the bedrock is buried under alluvial fill. Differential 

movement in the earth's crust appears to be responsible for this condition. The few available well logs that show the total thickness of 

alluvium in the valley fills indicate that the deposits range in depth 

from 60 to 150 feet in the Tia Juana, Sweetwater, and San Diego River 

Basins, to more than 200 feet in the San Luis Rey and Santa Margarita 

River Basins. Much of this fill is favorable to the storage of water, 

and a large part of the agricultural development in San Diego County has 

taken place on these valley lands, from the subsurface reservoirs of which 

water for irrigation is pumped.

Effect of geology on flood runoff

The greater part of the San Diego area is characterized by geologic 

features favorable to the absorption of rainfall. The widespread distribution in the mountain highlands of deeply weathered and disintegrated 

granite, with its granular and porous soil covering, is especially favorable to this action. The moderate slopes and limited extent of outcrops 

of the bare rock likewise facilitate absorption. The quantity of rainfall 

that such an area will absorb is not accurately known, nor can the rate of 

absorption be definitely stated. It is known, however, that storms of 

moderate intensity and duration produce little runoff unless they have 

been preceded by substantial amounts of rain.

Large supplies of ground water have been developed in the granite 

residium in a number of the upland valleys and flatter slopes. In the 

vicinity of Fallbrook, for example, a group of wells sunk into the disintegrated granite yields eufficient water to support a considerable acreage 

of citrus groves. Similar conditions exist in a number of other localities, indicating that a large part of the mountain area has surface and 

subsurface characteristics favorable to the absorption of rainfall.

Conditions over the coastal belt generally are less favorable to 

rainfall absorption. Except in areas covered by recent alluvial deposits, 

the soils are shallow, in most areas not exceeding 12 to 18 inches in 

depth. They tend toward the compact clayey type and are underlain by a
306 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

tight, partly or completely cemented subsoil, which merges into impervious 

marine sediments below. Such surfaces are likely to yield large runoff 

from rains, because their retentive capacity is limited to a part of the 

pore space of the upper few inches.

The river valleys, with their extensive alluvial deposits, have a 

large capacity for subsurface storage and hence should contribute materially to the reduction of runoff peaks. However, two factors tend to 

prevent this reduction. The first is the factor of time: peak flows last 

only a few hours as a rule and the amount of percolation that can take 

place during such a short period is necessarily relatively small. The 

second is the factor of available storage space: in many of the valleys 

no attempt is made to utilize the subsurface water supplies, so that in 

some places the ground water stands within a foot of the surface during 

most of the year, and in many areas where pumping is practiced the water 

table is lowered only a few feet during the irrigation season. The net 

result is a relatively small reduction of flood flows. This condition is 

probably responsible, in part, for the high stream flows that result from 

rains that have been preceded by heavy storms. The small available storage is filled by the runoff from the earlier storms, leaving no capacity 

for retention of subsequent flows. The effect of antecedent precipitation 

is carried over from one season to the next and may extend over two seasons, as is indicated by the following table prepared by Charles H. Lee 

on the basis of his investigations in this area. 21 (See table 24.)

Table 24.- Average depth of precipitation, in inches, required to produce 

runoff on certain streams in the San Diego area

Stream

San Luis Rey

Santa Ysabel

River near Pala

Creek near Ramona

San Diego River at diverting dam

Sweetwater River at Sweetwater dam

First year

after year

with less

than 90

percent of

average

rainfall or

second year

after one

with 70

percent or

less

6.7

7.6

8.5

11.3

Following an

average year

(90 to 110

percent of

average

rainfall)

4.3

4.9

5.3

7.8

Following a

year with

more than

110 percent

of average

rainfall,

except

second year

after one

with 70

percent or

less

1.4

3.7

3.1

5.7

21 Ellis, A. J., and Lee, C. H., Geology and ground waters of the 

western part of San Diego County, Calif.: U. S. Geol. Survey WaterSupply Paper 446, p. 97, 1919.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 307

It is not clear whether the water retained from wet years is distributed over an entire drainage basin or is confined to its alluvial 

valleys, but it is probable that the whole basin is affected.

In general, geologic conditions are such that runoff from the Tia 

 Juana, Otay, Sweetwater, San Diego, San Dieguito, San Luis Rey, and Santa 

Hargarita Rivers will be affected approximately as follows: in the part 

of the area underlain by the granite, light and moderately heavy rains 

occurring early in the rainy season will be largely absorbed by the surface mantle, and any water that reaches the streams will probably percolate into the alluvial fill of the river beds. On the mesa lands of the 

coastal belt, runoff is likely to follow all except the lightest storms. 

Heavy and intense late-season storms, especially if preceded by other 

heavy rains, are likely to produce flood flows from the mountain areas, 

and such flows will probably not be reduced by absorption in the river 

channels. Heavy precipitation in the preceding year will cause greater 

runoff from all parts of the area and from storms of all types.

San Bernardino mountain area 22

The San Bernardino Mountains include the eastern part of the great 

uplifted mountain block that extends from the Salton Sea depression norttiwest to the Santa Clara River Valley. The San Andreas fault cuts diagonally through the block near its central part, forming Cajon Pass, which 

has been adopted as the dividing line between the San Bernardino Range on 

the east and the San Gabriel Range on the west.

The San Bernardino Range is bounded on the south by that part of the 

San Andreas fault which extends southeastward from Cajon Creek through 

Potato Canyon and San Gorgonio Pass. The remarkably straight southwest 

front of the mountains is the dissected scarp of this fracture. San Gorgonio Pass is considered to be a graben associated with this same faulting, 

the depressed block forming the divide between the San Bernardino and San 

Jaclnto Ranges. On the north side of the San Bernardino Range, less 

spectacular but nevertheless distinct fault lines and escarpments mark 

the boundary between the mountains and the Mojave Desert. Thus the mountain mass consists of a great block of the earth's crust pushed up several 

thousand feet between two lines of faulting.

22 See also Vaughan, F. E., Geology of San Bernardino Mountains 

north of San Gorgonio Pass: California Univ., Dept. Geol. Sci., Bull., 

vol. 13, no. 9, pp. 319-411, 1922. Eckis, Rollin, Geology and ground 

water storage capacity of valley fill: California Dept. Public Works, 

Water Resources Div., Bull. 45, 1934; Noble, L. F,, Excursion to the San 

Andreas fault and Cajon Pass: 16th Internat. Geol. Gong. Guidebook 15, 

pp. 10-21, 1932.
308 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The structural features associated with the foundation of the range 

have caused two distinct and contrasting types of topography steep north 

and south boundaries and a comparatively subdued plateau area that forms 

the interior of the range. This plateau area, which includes Bear Valley 

and the part of the Santa Ana drainage basin above Seven Oaks, is 10 to 

15 miles wide, and about 30 miles long. The subdued topography, gentle 

slopes, and extensive open valleys indicate that it may formerly have 

been a partly peneplained area uplifted with the mountain range. North 

of this plateau the surface slopes sharply to the level of the desert, 

and south of it to the upper Santa Ana River Valley. Here the streams 

and washes have cut deep gorges into the frontal scarps, resulting in the 

characteristic rugged terrain common to the mountain boundaries.

Geology of the San Bernardino Range

Information concerning the distribution of rock types in the San 

Bernardino Range is incomplete, but the general extent of the various 

formations and their effect on the rainfall-runoff relation may be outlined. The most widespread formation found in the mountain area consists 

of a coarse crystalline granite locally intruded by dikes of siliceous 

porphyry. One large mass of this granite extends from Cienaga Seca and 

Rattlesnake Creeks eastward to the limits of the range; another mass extends south and west from Big Meadows and Santa Ana Canyon to the faulted 

sections along the southern boundary; and a third mass extends west from 

Bear Lake, which is north of the crest of the range, to Cajon Pass. In 

certain areas along the stream beds the granite is buried under fan deposits of unconsolidated alluvium. One such area parallels the Santa Ana 

River between Big Meadows and Seven Oaks; and others occur in Bear Valley, 

along Holcomb Creek, and in Millard, Hathaway, and Protrero Canyons. 

These deposits represent remnants of a formation that formerly extended 

across the canyon floors when the range was at a considerably lower altitude. Subsequent uplift and rejuvenated stream action have caused partial 

erosion, leaving the remainder of these deposits as benchlike features 

flanking the stream beds.

Associated with the granite are widespread masses and belts of contorted schists and gneisses of variable character. The largest mass 

extends south from the San Bernardino and San Gorgonio Mountains to San 

Gorgonio Pass and the mouth of Whitewater River. Another mass follows 

the crest of the range west from Bear Creek Gorge to Cajon Pass and occupies practically all the area between the San Andreas and Cleghorn
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 309

faults* The metamorphio rooks are intruded in many places by granite, 

with the foliation commonly extending through the granite.

Sedimentary rooks including limestone and quartzites of carboniferous 

age OP older, make up much of the range on the desert side east of Arrastre and Rattlesnake Creeks. These rocks are folded and faulted, and in 

many places are intimately associated with the adjacent schistose and 

granitic formations. One belt of quartzlte extends north from Cienaga 

Seoa and Sugarloaf Mountain across Broom Flat and Baldwin Lake. Holcomb 

Valley, northwest of Baldwin Lake, is surrounded by exposures of limestone 

and quartzite*, with younger alluvium occupying its central parts..

Deposits of shale, sandstone, and conglomerate of Tertiary Age or 

younger occupy narrow belts and wedges along the San Andreas fault below 

Cajon Pass and San Gorgonio Pass. East of Devil Canyon the fault block 

between the San Andreas and Mission Creek faults consists largely of a 

coarse-grained arkose sandstone and conglomerate. The upper reaches of 

the Oajon Creek Basin, including the area north of the San Andreas fault, 

are underlain by coarse-grained sandstone interbedded with small deposits 

of shale and impure limestone. This same formation appears between Cleghorn Mountain and Horsethlef Canyon and the flanks of the mountains along 

the Mojave Desert. The position of these isolated sedimentary blocks Is 

due to fault movements, and the beds as a rule are highly distorted and 

displaced. Dips up to 70° are not uncommon, and some of the strata are 

overturned.

Much of the major faulting in the San Bernardino Range is confined 

to the south-border areas and is a part of or closely associated with the 

San Andreaa fault system. The Mission Creek fault is one of this group. 

Its scarp lies a few miles to the north of and parallel with the San Andreas fault, and it extends from Devil Canyon through Mill Creek and the 

headwaters of the Whitewater River into Mission Creek. The spectacular 

box canyon at the head of Hill Greek appears to have resulted from stream 

erosion along this break. There is evidence that ssveral other faults, 

whose strikes range from east to northeast, branch off from the Mission 

Greek fault. Most of these appear to be Inactive and their effect on the 

topography has been largely obliterated by erosion. On the north side of 

the range several faults are known to strike northwest from the mountain 

area into the desert, but their influence on runoff is probably not significant.
310 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Between Waterman Canyon and Lone Pine Canyon several lines of faultIng that strike east and southeast branch off from the San Andreas system. 

One line cuts through Waterman Canyon and Is the source of the hot springs 

known as Arrowhead Hot Springs, while another branches off at Cable Canyon 

and cuts through Devil Canyon about l£ miles from Its mouth. The complex 

structure found In the lower part of Lone Pine Canyon and reaching through 

Cleghorn Canyon Into the West Fork of Mojave River has resulted from movement along the San Andreas and Cleghorn faults.

In addition to the major faulting In the San Bernardlno mountain 

area, practically the whole of the mountain surface Is broken by Innumerable closely spaced Intersecting fractures and Joints. Although this 

faulting action was probably not so severe as that affecting the San Gabriel Range, nevertheless It Is of major Importance In Its effect on 

runoff. Each break offers opportunity for the absorption and retention 

of rainfall. It likewise Is conducive to weathering and the creation of 

a residual covering, because fractured and jointed surfaces are subject 

to deep disintegration and rock decay due both to the weakened condition 

of the bedrock and to the accessibility of percolating waters.

Effect of the geology on the runoff

Several geologic features of the San Bernardino Mountains have notable effect on the runoff. There are, for example, considerable differences 

in the types of soil mantle covering the different formations. Generally, 

the metamorphic rocks are more resistant to weathering than the granites, 

and in the main they form steeper slopes and are covered with a shallower, 

more altered, and less pervious mantle, which in turn supports a lighter 

growth of vegetation. Bedrock fractures, although prominent, do not exhibit the deep disintegration found in the granites, and as a consequence 

there is less opportunity for percolation of rainfall. Runoff from such 

areas is, therefore, likely to be at a maximum. The unconsolidated fan 

deposits found in places along the rivers and in some of the upland valleys are, on the other hand, exceptionally well situated to absorb large 

quantities of rain, and runoff from these areas should be at a minimum. 

The granite areas, with their deep mantle of granular soil and heavy vegetal covering, and the areas of older sedimentary rocks, blanketed with 

extensive accumulations of talus, will show runoff characteristics between 

these extremes.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 311

Faulting has an influence on runoff for a number of reasons. The 

recently formed fault scarps are generally very steep, their soil mantle 

is shallow, and rock outcrops are common. These factors, unfavorable to 

rainfall absorption, are somewhat offset by the deep gravel deposits generally found in the beds of the streams that have eroded their channels 

along fault lines. Some water probably percolates to considerable depth 

along fault lines, but the amount may be too small to have any noticeable 

effect on direct runoff.

Streams draining the San Bernardino Range may be divided into two 

classes those that drain the interior parts of the range and those that 

drain only the steep frontal area surrounding the range. The Santa Ana 

and Mojave Rivers belong to the first class; while many smaller streams 

and washes, each of which debouches independently upon the desert or valley floor, make up the second class. Mill, Cajon, and Lone Pine Creeks 

have drainage basins that have been materially affected by faulting, and 

they will be discussed separately.

Mojave River

The basin of the Mojave River includes all the northwest part of the 

San Bernardino mountain area and extends from the divide west of Bear 

Lake to Cleghorn Mountain. Although this drainage area is extensive, 

most of the flow from it originates in a belt a few miles wide just north 

of the divide. The rainfall diminishes rapidly from this belt to the 

northern edge of the plateau, where desert conditions are prevalent.

In the northern part of the basin the streams have cut deep gorges, 

but these are separated by wide stretches of flat or gently rolling 

tablelands. The country rock is predominantly a massive coarse-grained 

granite, closely jointed and fractured. It weathers to a coarse porous 

mantle that is only slightly altered. Vegetation is scattered and sparse. 

Generally, conditions are those characteristic of a non-wa^er-producing 

area. The shallow side washes and the lack of erosion channels indicate 

a scanty runoff, and it is unlikely that this area produces runoff in any 

considerable amount except during the most intense storms.

In the upper part of this drainage basin, near the crest, there id a 

marked change in both topography and surface covering. The canyons change 

to open valleys with subdued divides and gentle slopes, and in many places 

they widen to form broad flats in which the ground-water table is near 

the surface and marshy conditions prevail. The country rock which includes both schist and granite, is generally buried under a thick soil

454720 0-42-21
312 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

mantle. Observations In dam excavations and road cuts show that the 

mantle may be from 5 to 30 feet deep In the valley areas and somewhat 

less on the side slopes. In section It ranges from a fine loam at the 

surface through a well-decomposed somewhat clayey subsoil to the disintegrated bedrock below. The area Is well forested with pines, except on 

the higher ridges, where a heavy growth of chaparral thrives.

The prevailing type of soil mantle has a large capacity for absorbing water, but apparently the Infiltration takes place slowly. Drainage 

likewise Is slow, as Indicated by the prevalence of seeps and springs in 

road cuts and in favorable spots along the slopes, many of which flow until late In the summer. Marshlands remain saturated throughout the year. 

The amount of flood runoff from such areas Is* largely controlled by the 

Intensity of the rainfall and the amount of antecedent rain. So long as 

the rain falls at a rate that does not exceed the rate at which infiltration will take place and ground storage remains available, there la likely 

to be little surface runoff, but as the rainfall increases and the ground 

storage becomes filled only a part of the water Is retained and runoff 

takes place. Again, If the antecedent rainfall has been sufficient to 

partly or completely fill all the ground storage, runoff can be expected 

from any storm. This was substantially the condition during the storm of 

March 1938. Most of the heavy precipitation of the 1936-37 season had 

been In the form of snow, and much of the water had been retained as 

ground'water, as indicated' by the prevalence of springs, seeps, and marshlands throughout the area during the late summer of 1937. Rains prior to

the storm of March 1938 may have been sufficient to practically fill the

» 

remaining storage space, and therefore the high Intensities of the March

storms were especially effective In producing the disastrous floods.

Santa Ana River

The drainage basin of the Santa Ana River above Mentone may be 

roughly divided Into an upper and a lower part, distinguished mainly by 

their topographic differences. The lower third of the basin, which includes the area between the valley floor and Flllrea Flat and Bear Valley, 

has a rugged terrain characterized by the deep V-gorges of the river and 

Its larger tributaries, exceptionally steep to precipitous slopes, narrow 

ridges, and an almost total absence of flat or moderately sloping lands. 

The country rook consists of schist and gneiss intruded'by coarse granite, 

both types being Intensely fractured and jointed. The netamorphio rooks
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 313

break down to a compact, well-altered, somewhat clayey type of soil, 

which, on the south slopes is usually shallow and capable of supporting 

only a light growth of vegetation, but on the north slopes is somewhat 

deeper and carries heavier vegetation. Such areas produce practically no 

talus accumulation and only a small amount of rock litter. The granites, 

on the other hand, weather to a coarse granular soil of considerable 

depth, on which rock litter is prevalent and vegetation as a rule is 

heavy.

The upper two-thirds of the basin, including most of the Santa Ana 

River Valley above Filirea Flat and all of Bear Valley, is in the high 

plateau region already described. With the exception of a few steep 

slopes leading from the higher mountains and ridges, the topography is 

mature and characterized by subdued ridges and broad open valleys.

Both Bear Valley and the lower part of the Santa Ana River Valley 

above Filirea Flat are underlain by fan deposits. In Bear Valley a considerable part of these deposits is submerged under the Bear Valley 

Reservoir and hence has no visible effect on the rainfall-runoff relation. 

Along the south bank of the Santa Ana, however, they occupy a bench ranging in width from a few hundred feet to more than a mile and extending 

from Big Meadows to Filirea Flat. Smaller fan deposits a-lso occur along 

the north side of the river at the mouth of Cienaga Seca Creek, between 

Holcomb Creek and Convers Flat, and at Filirea Flat. These deposits consist largely of unconsolidated coarse gravel, boulders, and sand, and 

their permeability is shown by the result of spreading operations being 

carried on by the Bear Valley Irrigation Co. at Barton Flat. This company 

has succeeded in increasing the summer flow in some of the tributaries of 

the Santa Ana River by spreading several thousand acre-feet of the spring 

runoff from South Fork.

The country rock along the mountain slopes above the bench south of 

the river consists of schist and gneiss intruded by granite. At lower altitudes the surface mantle is. a deep, much disintegrated, but somewhat 

rocky soil. These lower areas are covered with trees. On the hljjher ( 

reaches near the summits of San Bernardino Peak and San Gorgonio Mountain 

and the ridge connecting the two, vegetation is sparse and the slopes are 

fflantled with a disintegrated but unaltered rock litter. North of the 

river sedimentary rocks, consisting of quartzlte with minor amounts of 

limestone, crop out along the steep south flanks of Sugar loaf Mountain 

and the ridges leading from the mountains to the east. The quartisite.
314 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA *

breaks down Into blocky fragments, occasionally forming talus slopes of 

angular rock particles almost devoid of fine material. West of Sugarloaf 

Mountain the country rock Is granite, and the slopes are covered with a 

shallow, porous mantle formed by the disintegration of this rock. All of. 

the area except the quartzlte talus slopes support a moderately heavy 

growth of brush.

In any generalization regarding the effect of geology on the flood 

runoff from the Santa Ana River Basin the relative Influence of the two 

parts of the basin must be considered. Because argillaceous types of 

shallow soil cover most of the steep slopes of the lower part, percolation 

Is restricted and ground storage is limited. This part of the drainage 

basin Is, therefore, likely to show some runoff after any except light or 

moderate rains occurring early in the rainy season. If antecedent rains 

have been sufficient to fill the larger part of the pore space in the 

soil, its-retentive capacity is limited and the runoff is likely to be 

substantially increased. Under these conditions, rains of high intensity 

and long duration are practically certain to furnish runoff of flood proportions. These were the prevailing conditions during the storm of March 

1938, and it is probable that a large part of the Santa Ana River flood 

that followed that storm originated on these slopes.

" With extensive subsurface storage available in the upper reaches of 

the drainage basin, only the larger storms are likely to produce runoff 

in any great amount. The belt of alluvial deposits that parallels the 

Santa Ana River on the south between Seven Oaka and Big Meadows shows evidence of only a small amount of runoff from the storm of March 1938. The 

opposite or north side of the river yielded considerable runoff from the 

same storm. No extensive deposits of porous material are found along the 

south slopes of Sugarloaf Mountain. The light vegetation and the comparatively tight quartzlte bedrock of those slopes appear to favor copious 

runoff. The flood waters that damaged Seven Oaks and other resorts along 

the river appear to have originated on these quartzite slopes. Convers 

Flat, Filirea Flat, and Big Meadows are alluvial-fill areas providing 

considerable ground-water storage, and no doubt they acted to reduce the 

runoff to some extent. The porous granite slopes west of Sugarloaf Mountain would have a similar effect.

The records indicate that the direct runoff resulting from the storm 

of March 1938 was proportionately less along the Santa Ana River than 

along any of the neighboring streams. The subsequent summer runoff was 

likewise less and the retention correspondingly greater. The fact that
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTIHG FLOOD RUHQFF 315

the Santa Ana River is the only stream in the immediate vicinity that has 

belts of alluvium along its upstream drainage area appears to explain the 

condition adequately. These areas absorb water readily and apparently

yield it slowly, the carry-over perhaps extending from one season to another or even longer.

In considering the runoff from an entire drainage basin, such as the 

Santa Ana River above Mentone, the geologic factors may effect a balance 

between those areas that will yield almost complete direct runoff) from 

rainfall and those that will absorb most of the rainfall and yield it 

mainly from subsurface sources. Where geologic formations produce tight, 

nonabsorbent surfaces, such as rock outcrops or impervious clay soils, the 

flood peaks will be at a maximum and the drainage will be rapid, tut where 

geologic formations produce surfaces that favor rapid infiltration, the 

flood peaks will be reduced and the draining process will extend over a 

longer period. The parts of the Santa Ana River Basin possessing characteristics favorable for retention of water have a tendency to show a

smaller flood peak and higher subsequent runoff than other parts £>f the

i 

basin. ,

Mill Creek

Although Mill Creek drains a part of the frontal area, it shows a

I 

rainfall-runoff relation differing materially from that of the other

streams. Both the flood runoff and the summer runoff from its basin are 

consistently higher than from neighboring basins. Geologic features appear to be, in a large measure, responsible for this difference.

Mill Creek is a typicajL structural stream, and from its headwaters, 

Just south of San Gorgonio Mountain, to a point about 2 miles norltheast 

of the Crafton Hills it has excavated its canyon along the line of the 

Mission Creek fault. About 2 miles above its mouth the stream tulrns 

abruptly to the southwest, leaves the fault line, and cuts through the 

narrow block separating the Mission Creek and San Andreas faults, entering 

the Santa Ana Valley about 2 miles east of Mentone.

For about five-sixths of its length the creek is flanked on 

by a steep, precipitous fault scarp that is only slightly eroded

the

and dissected by a few steep, narrow gorges. Most of the tributaries entering

I 

from this side pass over waterfalls or steep cascades or flow dow|n steep,

shallow rock-floored washes. The slopes on the opposite side of the 

stream are considerably less precipitous in the lower parts of the basin 

but become steeper upstream, especially above High Creek, where they form 

the south wall of the box canyon. '
316 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The bedrock north of the canyon consists of granites, schists, and 

gneisses. The granites appear to predominate in the lower part of the 

canyon, and the metamorphic rocks in the upper reaches. The rocks of both 

types are only slightly disintegrated, rock exposures are common, and the 

mantle, if present, is shallow and rocky. Vegetation is sparse.

The high, steep ridge on the south that separates the basins of Mill 

and Potato Creeks, is made up largely of granite, although parts of it 

are underlain by a hard, coarse-grained, well-consolidated sandstone, designated by Vaughan 23 as the Potato sandstone. A wedge-shaped mass of 

the same material occurs north of the creek below the point where the 

canyon leaves the fault line near Morton Peak.' Both the sandstone and 

granite have weathered on the moderate slopes, to fairly deep, granular 

mantles, which support a heavy growh of vegetation. The upstream steeper 

slopes are barren.

Mill Creek Canyon is floored by coarse gravel and boulder alluvium. 

The deposits range in width from 200 feet above Fall Creek to a quarter 

of a mile or more In certain sections near the mouth of the canyon. The 

thickness of this alluvial fill is not known, but it is probably 100 fe*t 

or more. The many seeps and springs that originate in the fill are evidence of its pervious character and account for the comparatively large 

summer flow.

The rainfall-runoff relation in Mill Creek Basin may be interpreted 

from its geologic features. Within the northern part of the basin, where 

steep slopes, shallow soil mantles that support only sparse vegetation, 

and large exposures of rock, are characteristic, all storms are likely to 

furnish rapid runoff. Features such as these-are especially prominent 

east of Fall Creek, and there is evidence in the canyon that a large part 

of the floodwaters of March 1938 originated in washes draining from this 

area. In the box canyon at the head of the basin, both sides furnished 

heavy runoff. In contrast, the southern part of the basin, with its 

dense vegetation and porous mantle, would probably have little or no runoff from any but heavy storms. It is possible that the storm of March 

1938 produced some runoff from this area but from surface appearances 

most of the rain that fell here was absorbed.

23 Vaughan, F. E., Geology of San Bernardino Mountains north of San 

Oorgonio Pass: California Univ., Dept. Oeol. Scl., Bull., vol. 13, No. 9 X 

pp. 319-411, 1922.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 317

The summer flow In Mill Creek seems to come largely from the alluvial 

fill in the channel. A few streams on the north, including Fall, Mountain Home, and Town Creeks, have their sourcea on the high slopes of the 

San Bernardino Mountains and are perennial, but their contributions account for only part of the flow. All the streams draining from the south 

ordinarily dry up during the summer. The opportunity for infiltration 

presented by the flood waters flowing over several miles of the porous 

fill in Mill Creek channel favors a large absorption during storm periods 

with subsequent draining out during spring and summer.

i 

The frontal streams

The frontal area of the San Bernardino Mountains may be defined as 

the steep belt surrounding the range and forming the transition between 

the high and oomparatively level interior plateau and the lowlands of the 

Santa Ana Valley and the Mojave Desert. It extends from San Gorgonlo 

Pass on the southeast around through Cajon Pass on the west to Burns Canyon on the northeast.

Of the streams that drain this frontal area only those debouching 

into the upper Santa Ana River Basin have flood problems that are of 

economic importance. The north frontal washes draining the belt between 

Oa jon Pass and Biirns Canyon are subject to periodic and at times I intense 

and spectacular floods. They debouch, however, onto a sparsely settled 

or uninhabited desert area, and their geologio features are not here discussed. ;

From Cajon Pass to the Santa Ana River the south front of tide San 

Bernardino Range represents the disseoted soarps of the San Andreas and 

associate fault systems. A number of streams have established drainage 

basins on the mountain front, eaoh of these empties Independently onto 

the valley floor. For the most part, they are typioal consequent streams 

that have oarved their pattern on the uplifted mountain blook. tn general, the area is characterized by steep slopes and narrow ridges, rugged 

in places, with bedrock outcrops, deep main gorges with shallower, 

steeper tributary gorges arranged in dendritic patterns. A medium to 

heavy growth of chaparral and brush covers the area except on rooky 

patches and on some of the steepest slopes, where the soil mantle is too 

shallow and unstable to support plant growth. j

The bedrock of the frontal area consists mainly of schists and 

gneisses intruded by dikes and large bodies of massive coarsely Crystalline granite. The location and extent of the intruded granite rocks are
318 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

not accurately known, but outcrops have been observed In the lower parts 

of Devil and Waterman Canyons and In the upper reaches of Strawberry 

Creek. It is probable that a detailed examination would disclose these 

rocks In other parts of the area. Minor exposures of sedimentary rocks 

are also found in the area, distributed along the north side of the San 

Andreas fault. From Cable Canyon a narrow belt of nonmarine sandstone 

and conglomerate, half a mile to a mile wide, extends west along the 

fault line Into Cajon Canyon. Another belt of rocks of the same type extends east from Devil Canyon and forms the block that separates the San 

Andreas and Mission Creek faults. Both the sedimentary and crystalline 

rocks are closely fractured, although the sedimentary deposits, being 

rather poorly consolidated, show little surface evidence of this weakness. 

The surface mantle ranges in character from a deep granular, much disintegrated and altered soil in the more level areas, which are underlain by 

the granite formations, to the shallow clayey types of soil found on the 

steeper slopes, which are underlain by the metamorphic rocks. Occasional 

small outcrops of bare rock are found on the steepest slopes. Accumulations of talus are rare, and the stream beds are, for the most part, 

swept clean of debris.

The frontal area is similar in many respects to the lower part of 

the Santa Ana River Basin and the rainfall-runoff relationship of the two 

areas is comparable. Light rains are retained, but as ground storage is 

limited, owing to the shallowness of the soil covering and the lack of 

talus deposits, intense storms cause rapid runoff and flashy floods with 

sharp peaks, followed by rapid recession as the storm ends. The summer 

flow is small and is limited to the larger streams. The smaller streams 

are dry except during short periods following substantial rains.

Cajon Creek

The headwaters of Cajon Creek and most of its drainage basin are In 

a wide valley lying between the San Andreas fault and the summit of the 

San Bernardino Range and known locally as the Cajon Ampitheatre. Faulted 

and tilted sedimentary rocks, predominantly sandstones of Miocene and 

Pliocene age, underlie most of the basin, and thick gravel deposits of 

Pleistocene age overlie the sandstones along the rim to the north, formIng a series of Infacing bluffs. Nearly half of the basin Is blanketed 

under deposits of alluvial gravel. These follow the main stream channel 

and extend In a flngerlike pattern over the lower depressions of the 

basin.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 519

Southeast of this basin, in the vicinity of Cleghorn Mountain and 

between Cleghom Canyon and the San Andreas fault, the country rcjck consists of granite, schist, and gneiss. These resistant rocks forni steep 

slopes, many of them showing rock exposures, and the remainder aa.Ij 

partly covered by a thin veneer ^Sf sandy and rocky material. Beljow the 

point where Cajon Creek crosses the San Andreas fault at the moutjh of 

Lone Pine Canyon, the stream Is flanked on the south by a low r!4ge of 

schist and granite and on the north by a belt, a mile or so wide,j of low 

ridges and mounds lying between the channel and the fault. These ridges 

and mounds are capped by gravel deposits that are apparently remnants of 

old terraces. Below Cable Canyon, the canyon widens as the wash enters 

the upper reaches of the broad, flat alluvial cone.

The Influence of geology on the rainfall-runoff relation in iCaJon 

Creek Basin appears to be restricted to the ability of the porous) alluvial 

gravels to absorb the runoff from the surrounding impervious fomtatfons. 

The exposed sedimentary rocks in the upper basin appear as steeply tilted 

blocks, the Inclined strata, in many instances forming steep dip slopes 

that are almost devoid of any covering. In localities where the slopes 

are less steep the mantle covering usually consists of a very thin layer 

of porous sand. The underlying bedrock, though well jointed, may! be considered as too impermeable to have any appreciable effect on rundff. The 

granite and metamorphlc formations found In Cleghorn Canyon and l)n the 

steep northeast escarpment of the San Andreas fault which parallels the 

lower part of Cajon Canyon are also characterized by a thin soil mantle, 

sparse vegetation, and considerable areas of bare roek slopes. Tjhese 

areas can be expected to yield a high runoff from any but light Sains.

The many local floods which are common in this vicinity originate on these

t 

slopes, and, although they are'flashy and spectacular at particular points,

their effect Is not widespread, because their waters are usually absorbed 

by the porous gravels of the lower stream bed. Under ordinary storm conditions it appears that all runoff would be absorbed by the" gravels an*

that only during long intense rains would flood conditions prevail! over

i 

the entire stream.

Lone Pine Creek

Lone Pine Creek Is unusual among the streams of the immediate mountain area in that It not only shows very little runoff from individual 

storms but it also requires a longer period in draining out. Geological 

conditions appear to be responsible for this behavior. The stream follows
320 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

the line of the San Andreaa fault for ita entire length, and ita drainage 

baa in haa the long narrow outline typical of structural basins. Although 

thia basin ia 10 milea in length, ita maximum width doea not exceed 2 

milea. In common with other areaa along the fault in thia vicinity, opposite a idea of the valley ahow diaaimiletr rook formationa. The ridge on 

the south is composed of Pelona schist, the formation which ia found alao on 

the north aide of Lytle Creek and ia deaoribed In connection with that 

stream. The relatively gentle slopea of thia ridge are mantled with a 

fine-textured micaceous soil that oarriea a small amount of rock litter 

but no talua aooumulationa. Although the surface ia covered by a moderate growth of brush, there ia evidence of oonaiderable eroaion, and many 

of the shallow aide waahea are floored on bedrock.

Rooka found in the ridge along the oppoaite north flank of the canyon 

include both sedimentary and granitic typea. For aeveral milea upstream 

from the mouth of the canyon at Cajon Creek, the ridge ia made up of sedimentary rook broken into a aeriea of complex fault blooka. A wellconsolidated arkoaio sandstone ia the predominating type. North of theae 

faulted structures, the ridge oontinuea aa a narrow wedge of only slightly 

weathered granite. Both the sedimentary and granitic alopea have characteristics unfavorable to the retention of rainfall. The aoil mantle ia 

thin and aoattered, being interrupted by many small areaa of expoaed rook. 

Vegetation ia aparae and oonaiata mainly of aoattered clumps of stunted 

bruah.

The floor of the valley ia covered with depoaita of alluvial fill 

throughout moat of ita length. On the aouth thaae depoaita extend well 

up on the alopea, but on the north there ia a sharp line of demarcation 

between the comparatively level floor of the valley and the ateep sandstone and granite alopea. A oroaa aaotion of the fill aa expoaed in a 

recently eroded waah near the mouth of the canyon shows it to be composed 

of unconsolidated gravel and sand, with many thin beds of micaceous silt. 

Tn* depth of the fill at this point is about 60 feet, but inasmuch as the 

exposure occurs near the ridge several hundred feet aouth of the fault 

line and at a point of rising ground water, this depth cannot be considered as representative of the entire valley. Recent action along the 

San Andreas fault has affected the fill structure. The sag pond near the 

mouth of the canyon, known locally as Lost Lake, and several low ridges 

and scarps farther up the valley appear to be the results of movement 

along the fault line.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFFJ 321

The comparatively low flood runoff from storms falling on thu Lone 

Pine Creek Basin may be attributed to the absorptive capacity of "he 

gravels in the valley floor, but the reason for the slow draining I out ia 

not entirely clear. One possible explanation is that recent fault action 

may have formed a series of isolated pervious pockets in the fill. Slow 

drainage from these pockets would furnish a stable flow to the stream for

long periods. It is possible also that water may escape along thfc fault

i

and appear at the surface at points outside the drainage area. Sipme observers believe that water passes through the complex fault linesjat the 

mouth of the canyon, moving from the Lost Lake area into Cajon Cr^ek at a 

point above the Cajon Creek measuring station. Again it may be that the 

presence of lenses and beds of the fine micaceous silts in the fill has 

some effect on runoff. These saturated beds would yield water at slow 

rates for long periods. There is no visible evidence to support ifuiy of 

these assumptions, and it may be that the stream's behavior is dui& to a 

combination of all of them. j

Upper Santa Ana Valley |

I The southwest front of tehe San Bernardino Range is flanked bjr the

eastern part of the upper Santa Ana Valley. Structurally this part of the 

valley is a buried fault block depressed between the San Andreas and San 

Jacinto faults. On the northeast aide the boundary is sharply defined by 

the straight-line contact between the valley alluvium and the crystalline 

rock of the mountains. The San Jacinto fault has a less distinct^ though 

definite, surface expression in the low escarpment that marks the south

bank of Lytle Creek. It is well known that this escarpment, known locally

j

as the Bunker Hill Dike, acts as a barrier to underground flow.

The valley floor is a broad alluvial plain whose slopes converge toward the intersection of Warm Creek and the Santa Ana River near Oolton. 

At the front of the mountains the streams have built up a series of, alluvial cones that extends eastward from Lytle Creek to the Santa Ana River.

From Devil Canyon to the Santa Ana River the cones coalesce to foirm a eoni

tinuous upland bench broken at the valley margins by the intercon^.1 depressions. Near their apexes the slope of the cones is from 150 jbo 250 

feet to the mile, but it gradually decreases until at the lower end of the 

valley floor it is 25 to 50 feet to the mile. The upper parts of the cones 

have been dissected and the parent streams occupy well-defined channels. 

Lower down these channels are broader and divide to form a network of 

gravel-strewn washes, dry except during periods of high stream flow.
322 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

The valley fill consists of unconsolidated sands, clays and gravels 

in many places more than 1,000 feet deep. There is little or no evidence 

of sorting or classification of materials except along the stream courses. 

There the deposits reflect the changing gradients from the relatively 

steep alluvial cones to the fi^at valley lands, with coarse materials predominating in the area near the mountains and fine silts and clays 

predominating in the adjoining low lands. This sorting is by no means 

regular, however, for accumulations of coarser debris in the valley fill 

occur throughout its extent. In the vicinity of San Bernardino several 

of these more pervious beds are capped with partly impervious clay blankets near the surface, and this clay covering together with the barrier 

formed by the San Jacinto fault, is responsible for the well-known San 

Bernardino artesian basin.

The Santa Ana Valley is an important source of underground water in 

southern California. The capacity of the basin to absorb additional water 

no doubt exceeds the runoff from any single storm or series of storms 

likely to occur, but the opportunity for absorption is limited by the rate 

at which percolation can take place during the usually short periods of

 ^

high runoff. Ordinarily the water of streams entering the valley is entirely absorbed within a few miles beyond the mountains. Because of their 

low flow the streams seldom spread to any great extent, and the absorption 

takes place along a single channel area. As the runoff increases the 

streams tend to spread and occupy additional channels and washes, thus Increasing the area over which absorption can take place. During the larger 

floods the streams, unless artificially restricted, spread and occupy a 

large part of the cone area; percolation thereby is naturally increased 

and peak flows are proportionately decreased. The cones at the mouths of 

the Santa Ana River, City Creek, and Plunge Creek are especially well 

situated to absorb additional water by this process. The relatively short 

period of the flood flows seldom more than a few days limits the amount 

of flood water actually percolating underground.

San Gabriel mountain area

The San Gabriel Mountains and the valleys flanking them on the south 

form two distinct physiographic and geologic units. The mountain area 

characterized by high, sharp tirests, deep canyons, steep and precipitous 

slopes, and sharply dissected boundaries, is in direct contrast to the 

broad, gently sloping valleys beyond. The economic value of the tillable 

lands in these valleys is due to this contrast, for without the mountains
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFFJ 323

to induce precipitation from the moisture-laden air masses moving {eastward 

from the Pacific Ocean and thus develop streams, the fertile valley lands 

would be nothing more than a desert. At the same time this contrast is 

responsible for a flood hazard that increases in gravity as the population 

increases and the lands become more valuable.

San Gabr.iel Mountains

The San Gabriel Mountains represent the western part of the great uplifted block of which the San Bernardino Range is the eastern par^;. In

I 

extent the San Gabriel Mountains reach from Cajon Pass on the east to San

Fernando Pass and the Santa Clara River on the west and northwest, and

from the Mojave Desert on the north to the Santa Ana, San Gabriel^ and

i 

San Fernando Valleys on the south and southwest. Within this are^i the

mountain tops range in altitude from 3,000 feet in the foothills ^outh of

the Santa Clara River to more than 10,000 feet at San Antonio Peak, near

i 

the northeast edge of the range. The main crest of the range follows an

irregular line nearer to the north boundary than the south boundary, but

i 

there is a secondary, parallel crest of slightly lower altitude extending

along the south edge of the mountains and forming the ridge between the. 

East and West Forks o/ San Gabriel River and the valley.

A narrow belt of more subdu«d topography occurs just south of the 

main divide, extending from Charlton Flats on Tujunga Creek to Pine Flat 

on the North Fork of San Gabriel River. This belt ranges in altijbude from 

3,000 to 6,000 feet and is considered to be the uplifted segment pf an 

ancient land surface. Although its topographic features are similar to 

those found in the plateau region of the San Bernardino Mountains], the 

total area of the San Gabriel belt is much less extensive. It is probably 

sufficiently large, however, to exert an influence on flood runoff, as its 

topography,'geology, and vegetation are all favorable to the rapid, absorption of rainfall.

The main streams draining the San Gabriel Range have cut deep Vgorges, and most of these are at or near grade. There is evidence of 

some aggrading in the stream channels, particularly in the lower Reaches 

of the San Gabriel, Tujunga, and Arroyo Seco Canyons. The channels of 

most of the other streams are swept clean. Tributaries to the main rivers 

and creeks are numerous, with the result that the mountain topography is 

a complex network of steep canyons and sharp narrow ridges.
324 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 

Geology of the mountain area 24

Igneous and metamorphie rooks are the predominant types of rook formations found within the San Gabriel Mountains. Alluvial deposits flank 

the range on the south at the elevation of the stream valleys and on the 

north at the level of the desert, and a few scattered remnants of old alluvial stream terraces are found in belts and patches along some of the 

stream channels. A small area of sedimentary rocks consisting largely of 

sandstone and conglomerate of Tertiary age crops out in the uplifted fault 

block south of the San Gabriel fault between Tujunga Canyon and Pacoima 

Wash. With these exceptions no unmetamorphosed deposits of sedimentary 

origin are found within the mountain area.

The metamorphic rocks have the greatest areal extent. They consist 

mainly of a complex mass of granitic and dioritic schists and gneisses 

with occasional lenses of quartzite and altered limestones, some of which 

are more than a hundred feet in width. This aggregation has been intruded 

by large masses of crystalline granitic rocks, and the whole mass has in 

turn been cut by sharply defined dikes of aplite and diabase. In typical 

sections of gneiss the bands vary from a few inches to a foot in width, 

the lighter bands being composed of quartz and feldspar, the darker ones 

usually including biotite and hornblend. Much of the schist has a ribbonlike structure. Parting along the foliation planes in both the gneisses 

and the schists is not common in the unweathered rock, but as weathering 

increases the formations show a tendency to part along these planes and 

thus give rise to talus and litter composed of fist spalls.

The igneous rocks consist chiefly of granite's, granodiorites, and 

diorites, but there is a large area of anorthosite in the northwestern 

part of the range, extending from the upper Tujunga and Pacoima Basins to 

Soledad Canyon. The igneous rocks show considerable variation in texture 

and structure, which is, in turn, reflected in the type of mantle they produce. The granite at the head of Eaton, Rubio, and MiHard canyonstia 

coarsely crystalline and disintegrates to a deep, loose, granular soil.

24 See also Eekis, Rollin, Geology and ground-water storage capacity of valley fill: California Dept. Public Works, Div. Water Resources 

Div., Bull. 45, 1934; Hill, M. L., Structure of the San Gabriel Mountains 

north of Los Angeles, California: California Univ., Dept. Geol. Sol., 

Bull., 19, no. 6, pp. 137-170, 1930; Noble, L. P., The San Andreas rift 

and some other active faults in the desert region of southeastern California: Carnegie Inst. Washington Year Book, No. 25, pp. 415-428, 1926; 

Miller, W. J., Geology of the western San Gabriel Mountains of California: 

California Univ., Pub. in Math, and Phys. Soi., vol. 1, no. 1, pp. 1-114, 

1934.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 325

The granodioritea and anorthosites in the western part of the range have 

a similar texture but produce only shallow mantles of granular particles 

containing considerable rock litter. On the other hand, the diojfites, 

which outcrop at the head of the North Fork of San Gabriel River j in the 

vicinity of Mount lalip and Mount San Antonio, are fine-grained and denae 

and weather alowly to blocky fragments only slightly disintegrated.

Details concerning the distribution of the various rock formations, 

so far aa they are known, will be discussed in connection with the descriptions of the individual drainage basins.

Faulting

The northeast boundary of the San Gabriel Range follows the trend of 

the well-known San Andreas rift. Toward the east the fault line cuts 

' through the flank of -the range and is reflected in the long, narxjow depressions of Lone Pine Canyon and Swarthout Valley. West of Swaijthout 

Valley the boundary of the range swings several milea south of the fault, 

forming a broad reentrant between Rock Creek and the mouth of Leonis Valley. Beginning at the latter locality the fault again cuts the flank of 

the range,' passing northwestward through the narrow Leonis Valley and Pine 

Canyon sections. On the south of the range, the irregular but sharp 

boundary between the valley and mountain areas is formed by the Sierra 

Madre fault systems. In addition to these major faults, the interior part 

of the range is out into a series of blocks by other faults whose displacements vary from a few feet to hundreds of feet.

Many of the larger faults in the interior part of the range lare reflected in the topography, because the weakened fracture planes are 

especially susceptible to stream erosion. The great canyon of the East 

and West Forks of San Gabriel River has been eroded along the line of the 

San Gabriel fault. The courses of Papoima and Tujunga Creeks havje been 

determined in part by fault lines. Lytle Creek follows the line of the 

San Jaointo fault. Several of the frontal streams along the south flank 

of the range, notably Sawpit, Dalton, and San Dimas Creeks, have had their 

courses determined in part by arcuate faults branching off from tfie Sierra 

Madre system. La CaSada and Tujunga Valleys occupy a narrow fault graben 

that separates the Verdugo and San Rafael Hills from the main San Gabriel 

Range.
326 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

Minor faults and fractures are so numerous that it is inadvisable, 

in a report such as the present one, to attempt to discuss their location 

or movement. Their combined effect has been to convert the entire range 

into a weakened and fractured mass. Miller writes: 25

Still another feature should be mentioned here, namely, the high 

degree of minor fracturing of the whole San Gabriel region of 1,200 

square miles. The writer has never 3een another area of comparable 3ize 

so remarkably fractured. # * # It would seem that, during the uplift of 

the vast San Gabriel block of crystalline rocks, the whole mass was subjected to stresses which, in part at least, found relief in the development of countless fractures running in all directions.

Effect of geology on flood runoff

The San Gabriel Mountains possess two contrasting characteristics 

that affect the runoff from rainfall. The first is the very steep topography, which would ordinarily be expected to produce a large volume and 

high rate of runoff; the second is the exceptionally porous nature of the 

greater part of the mountain surface, which acts as an absorbent and tends 

to reduce direct runoff. The actual runoff from both ordinary and floodproducing storms represents a balance between these influences. Another 

unusual condition is the apparent lack of direct surface runoff in certain 

areas, even under the most intense rains, although the total discharge 

from such areas is substantial and the elapsed time between the peak rainfall on the drainage basin and the peak discharge in the river channel at 

the gaging station is practically the same as would normally be expected 

in areas where direct surface runoff takes place. The explanation of this 

seeming contradiction is probably to be found in certain geologic and 

physiographic characteristics. Except where rock surfaces are exposed, 

the mountain area is for the most part covered with a mantle of disintegrated but only partly altered rock particles, which ranges in depth from 

a few inches to several feet. On steep slopes this material shows a tendency to creep, with the result that the mass is continually being disturbed, the fine particles are buried and the coarse particles remain near 

the surface. Plants establish their root systems in the finer subsurface 

layers and deposit their litter at the surface, where it mingles with 

the coarser rock fragments. When it rains this surface functions as an 

absorbent, and water enters the mantle. Some of this water percolates, to 

a considerable depth, and the remainder moves about through the myriad of

25 Miller, W, J., Geomorphology of the southwestern San Gabriel 

Mountains of California: Calif. Univ., Dept. Geology, Bull. 17, No. 6. 

pp. 203-4, 1928.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 327

pore openings in the mixture of coarse fragments and litter and eventually 

eacapea into the many gullies and canyons leading down the slopes* During intense storms, auch aa those prevalent in March 1938, it ia likely 

that moat of the rain water remains under ground for only a short period 

and reappears almost immediately as stream flow, yet there is relatively 

little evidence of erosion except in the channels of streams that drain a 

large area, where a concentration of water is to be expected. In many of 

the drainage basins, the general surface shows little effect of erosion 

and the vegetal litter and soil particles are undisturbed, yet the floora 

of the stream channels are cut to bedrock.

Streams draining the San Gabriel Mountains may be divided into two 

general groups those that drain the steep frontal slopes, and those that 

have cut through the frontal scarp and drain the interior of the range. 

Streams of the first group include Deer, Cucamonga, San Antonio, San Dimes, 

Dalton, Rogers, Fish, Sawpit, Santa Anita, Eaton, and Millard Creeks and 

Arroyo Seco and many smaller streams. Although the courses of many of

these streams show the influence of faulting, they are for the most part

i 

typical consequent streams developed on the frontal scarp of the range

and are characterized by steep slopes, many tributaries arranged {in a 

dendritic pattern, and fanshaped watersheds. Tujunga and Pacoima Creeks 

and San Gabriel River belong in the second group. These are characterized 

by larger watersheds of irregular outline, main stream beds of low gradi9

ent, following fault lines over a large part of their courses, and 

tributaries of high gradient that generally enter the parent stream at 

right angles.

San Gabriel River

Although the courses of the East and West Forks of San Gabriel River 

follow the line of a recognized fault, it is doubtful if this structural 

feature has any significant influence on flood runoff. The canyon does 

not appear to have any of the characteristics of a fault graben, and although the zone of fracturing seems to be fairly wide, the surfade features of the zone are not materially different from those of the jareas 

flanking it. Type of country rock, depth and stage of disintegration and 

overlying vegetal cover appear to be the controlling factors in t|he relation of runoff to rainfall. j

A belt of rocks consisting mainly of diorite gneiss intruded by 

masses of granodiorite and diorite extends along the East and We$t Forks 

of San Gabriel River from the head of Cow Canyon to the head of the West

454720 O - 42 - 22 -
328 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Fork. North of this belt, which includes the larger part of the drainage 

basins of Devil Canyon, Bear Creek, and North Fork of San Gabriel River 

and the part of the East Fork of San Gabriel River above Laurel Gulch, 

the country rock is predominantly granodiorite. A small outcrop of mica 

schist is found in the vicinity of Vincent Gulch and Prairie Fork at the 

head of East Fork of San Gabriel River, and the Crystal Lake region is 

buried under material that In some ways resembles morainal deposits. 

West of Chileno Canyon and south of the West Fork of San Gabriel River, 

the underlying bedrock is predominantly diorite and granodiorite; these 

are part of the same intrusive mass that appears throughout the Sawpit, 

Santa Anita, and Eaton Creek Basins.

Several features that influence the rainfall-runoff relation and the 

behavior of flood flows over certain areas appear to be traceable to the 

type of the underlying bedrock. One noticeable example is the sharp contrast between the north- and south-facing slopes along the West Fork of 

San Gabriel River. On the north-facing slopes south of the river the

granodiorite and diorite are weathered to deep granular soils that oon-

>

tain considerable humus and support a heavy growth of chaparral and conifers. Much of this area lies in a zone of heavier than ordinary rainfall, 

as noted in the section on local rainfall characteristics, p. 49. There 

are practically no exposures of bedrock, and the stream channels are, for

the most part, only slightly eroded, indicating that even during the storm

of March 1938 the runoff was not excessive. In contrast to this condition 

the south-facing slopes north of the river, underlain by gneisses and 

schists, show unmistakable evidence of heavy runoff. Here the planes of 

sohistosity stand almost vertical and the rook breaks down to small, angular, flat fragments only slightly disintegrated or decomposed. The soil 

covering is thin and finely granular. Steeper slopes show many areas devoid of soil covering, and the whole region is out into a network of 

shallow washes and gullies, each of which is almost invariably eroded to 

bedrock.

A similar contrast, though perhaps not so distinct, is apparent along 

the north-facing slopes south of the East Fork of San Gabriel River. The 

resistant metamorphio formations found north of the West Fork of San Gabriel River continue eastward into the valley of East Fork. The bedrock 

of the prominent, bold slopes along both the north and south flanks of 

the river is of this type. There slopes are bare or thinly mantled with 

soil, the vegetation is sparse, and the washes are rook-floored, all of
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFFJ 329

which features indicate a heavy runoff. About 2 miles south of the river 

the bedrock changes to a deeply disintegrated and well-altered schist. 

The schist is exposed in the upper part of Horse Canyon and in rojad cuts 

along the divide between San Dimas and Dalton Creeks and the San Gabriel 

River. Rounded ridges, moderate slopes, deep soil, and a heavy growth of 

brush characterize the area, all of them evidences of a comparatively 

light runoff.

The granodiorite that underlies most of the northern part ofl the San 

Gabriel River Basin is commonly of porphyritic texture and consists of 

white or light-colored plagioclase feldspar and quartz through which crystals of biotite and hornblende are scattered. The biotite and hdrnblende 

constitute only 1 to 5 percent of the total volume. Although the granodiorite is somewhat disintegrated by weathering, it shows little jevidence 

of decomposition, and the thin rocky to sandy mantle contains verjy little 

clay. The lower slopes are covered by coarse talus deposits of medium 

depth. Vegetation is sparse on the steeper slopes but is somewhajt thicker 

over flatter areas. At the head of Devil Canyon and on the slopejs of 

Mount Waterman, Mount Is lip, and other observed places, the gullies and 

washes have all been eroded to bedrock. In most areas the larger tributary channels have been similarly eroded. The high runoff and ccjncentration of flow in the West Fork of San Gabriel River during the storm of 

March 1938 appear to have resulted from the rain that fell on the; thinly

protected slopes of the Bear Creek, Devil Canyon, and Trail Fork Basins.

Precipitation during the same storm seems to have been sufficient! to saturate the talus accumulations as well as the soil mantle. Storms that do 

not provide enough water to saturate the soil will ordinarily give little

runoff. |

I

The formation at the head of the East Fork of San Gabriel Rj|ver appears to be a part of the Pelona schist described by Noble, 6 whl|ch occurs 

between the San Andreas and Lytle Creek faults. The formation re|adily 

disintegrates to particles of dustlike fineness and produces a deep mantle

of fine, compact soil, which would probably show high runoff fro4 any but

i 

light rains. Farther south, in the basins of Iron Fork and Soutti. Fork of

Iron Fork, the rock is decidedly more resistant, and weathering h]as produced great quantities of only slightly disintegrated rock slabs. These 

basins, for the most part, are devoid of soil or vegetation, and their 

surface would furnish direct runoff from any storm.

26 Noble, L. P., Excursion to the San Andreas fault and Cajon Pass: 

16th Internat. Geol. Gong. Guidebook 15, p. 12, 1932. 1
530 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The floor of the valley of North Fork of San Gabriel River is covered 

with a heterogenous mixture of angular rock fragments, soil, and litter 

that has the appearance of a glacial deposit. Crystal Lake occupies a 

lower depression in the characteristically hummocky surface of the area. 

The head of the canyon is a cirquelike amphitheatre considerably modified 

by erosion. Slopes surrounding this amphitheatre are steep to precipitous; many of them showing rock outcrops, and the remainder are mantled 

by shallow coverings of coarse rock fragments and talus. Several springs 

of substantial flow occur along the south margin of the alluvium above 

Sycamore Flat, Indicating that these deposits are highly pervious. It Is 

probable that in moderate storms much of the runoff from the surrounding 

area is absorbed, but when rainfall Is Intense the steep slopes of the 

amphitheatre must yield almost complete runoff, and from appearances only 

a part of this flow infiltrates to the subsurface storage. The wide, 

deeply eroded wash that crosses the area indicates a high runoff from the 

storm of March 1938, and it is probable that any storm of similar intensity lasting more than a few hours, will yield a proportionately high 

runoff.

Tujunga and Pacolma Creeks

The basins of Tujunga and Facolma Creeks have for the most part, 

neither the altitude nor the sharp, rugged topography characteristic of 

the San Gabriel Range farther east. Underlying rock formations are in 

part responsible for the difference. A belt composed of gneiss and 

schist occupies the south front of the range, forming an areal link between the granite and dlorite that occur in the vicinity of Echo Mountain 

and Mount Wilson and the sedimentary rocks that crop out in the head of 

Flacerita Canyon. This belt covers the lower part of Facolma Wash and 

the part of Tujunga Creek Basin south of an irregular line running from 

the mouth of Trail Canyon to Mount Josephine. The gneiss and schist have 

been Intruded by several wide dikes and other Irregular masses of dlorite 

and granodlorite, but in both its topographic form and the character of 

its mantle this belt resembles the belt of similar rocks north of the San 

Gabriel River. Sharp, craggy ridges, steep slopes, narrow V-shaped canyons, a thin, rock-littered mantle, and many rock outcrops are characteristic features.

On the north side of this metamorphlc belt the country rock is of a 

distinctly different character. Pacolma Creek Basin is underlain by dlorite and anorthoslte. The bedrock in the upper reaches of Tujunga Creek
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTIHG FLOOD RUNOFF 331

Basin consists of granodiorite, diorite, and anorthosite. These rocks are 

less resistant than the metamorphic types and have weathered to subdued 

ridges and somewhat open stream valleys. The moderately deep mantle covering them consists of rather finely disintegrated particles that grade 

almost imperceptibly into the intensely fractured parent rock. On the 

higher slopes this covering is perceptibly thinner, and there are occasional outcrops of rock, but on the more level surfaces and in the valley 

areas it increases in thickness, forming heavy accumulations of rather 

compact, well-altered clay soils. Vegetation is sparse on the steeper 

slopes but moderately heavy on soil-covered reaches. Both the surface 

and subsurface characteristics of this formation are favorable to the absorption of rainfall in small amounts, and for this reason light to 

moderate storms of short duration seldom produce increased stream flow. 

However, in intense storms, especially those of long duration, the comparatively shallow mantle along the slopes would probably reach saturation 

and, in that event, with deductions limited to the water that might percolate to the cracks and fissures of the bedrock, the runoff would be 

high. The impervious nature of the clay-filled valley soils would also 

contribute to high runoff from intense storms. These features probably 

account for the flashy floods shown by the streams under heavy precipitation.

The frontal streams

The frontal streams of the San Gabriel Range are similar to those of

the San Bernardino Range in that they drain only the steep mountain frcnts,

* 

in contrast to the larger streams that cut into and drain the interior of

the range. The San Gabriel frontal streams include Cucamonga, San Antonio, 

San Dimas, Dalton, Rogers, Fish, Sawpit, Santa Anita, Eaton, and Millard 

Creeks and Arroyo Seco and many other small streams. Their basins as a 

rule are fan-shaped, the stream and its tributaries commonly forming a 

dendritic pattern. Considerable variation both in type of bedrock and in 

nature of soil and vegetal covering is found in the frontal area, which 

in turn accounts for a noticeable difference in runoff characteristics.

The bedrock in the frontal area between Lytle Creek and the San Gabriel River Is almost exclusively mstamorphic, the predominating type being a 

diorite gneiss in which the gneissic bands are almost vertical and trend 

in an east-west direction, parallel with the range. The bands in general 

range in width from a fraction of an inch to 3 or 4 inches, but a few
332 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

widen to approximately a foot. In many areas the bands are very narrow 

and have a rlbbonllke appearance. The formation has been considerably 

shattered and broken.

The main stream channels have cut directly across the trend of this 

banding, forming deep canyons with steep walls, and this steepness, comblnded with the structural arrangement of the bedrock, which exposes only 

the edges of the bands, has prevented the formation of a deep mantle. 

Such soil as does exist consists largely of a thin blanket of disintegrated bedrock with a small amount of clay and considerable rock litter. 

Many of the slopes are almost devoid of soil, but are covered by shallow 

talus accumulations of small, flat rock fragments. Side washes and gulllea are generally floored with bedrock. The vegetation Is moderately 

heavy to sparse.

The areas drained by Etlwanda Creek, Day Canyon, Deer Canyon, a large 

part of Cucamonga Canyon and the lower part of San Antonio Creek Canyon 

all show these features. The runoff from such areas depends to a large 

extent on the characteristics of the storm that produced It. Both the 

soil mantle and the talus slopes are highly absorbent, but their retention 

capacity Is low. They act, however, In carrying the water to the cracks 

and fissures of the underlying bedrock. In Intense storms the rainfall 

Is likely to exceed the retention capacity of both the mantle and the bedrock, and then the excess must appear as runoff, the amount of which will 

be In direct proportion to the amount of rainfall. This water accumulates 

In the many side washes and gullies, where the increased flow has removed 

all debris and cleaned the channels to bedrock. Drainage from the watersheds is rapid, and all these streams, with the exception of San Antonio 

Creek, show only small amounts of summer runoff.

San Antonio Creek Basin differs from the basins of the adjacent 

streams to the east in that it has a substantial summer runoff. Naturally, 

much of the ordinary summer flow can be attributed to the snowfall along 

the higher slopes of San Antonio Peak, but certain geologic conditions 

also favor this runoff. North of an east-west line crossing the saddle 

at the head of Cattle Canyon, which is about the line of the eastward extension of the San Gabriel fault, the bedrock changes from the metamorphic 

types already described to slightly altered granodiorite and diorite. 

Jointing in these formations is more widely spaced, and the rock breaks 

down to coarse angular, blocky fragments. Rock exposures are common along 

the higher slopes, but the lower slopes are blanketed with heavy accumulations of talus. The upper reaches of the tributary stream channels are
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 333

eroded to bedrock but the lower parts, extending for some distance above 

the confluence with the main stream are floored with coarse angular alluvium.

In the vicinity of the old Toll House and extending upstream to about 

the mouth of Icehouse Canyon the bed of San Antonio Creek consists of 

gravel deposits. These range from about 200 feet to nearly a quarter of 

a mile in width. Above Icehouse Canyon the gravels are confined to a 

narrow belt along the stream channel. The thickness of these deposits Is 

not known, but in one area above Icehouse Canyon more than 100 feet Is 

exposed.

With storm precipitation in the form of rain, as in March 1938, these 

gravels act as an equalizing influence, absorbing a part of the direct 

runoff from the surrounding region, to be released later. The extensive 

talus deposits along the slopes and in the lower reaches of the side 

streams would act in the same way. It is evident that with storms of 

high Intensity similar to that of March 1938 only a part of the runoff is 

retained, but with moderate rains it appears that only minor amounts of 

runoff would escape. The remarkably consistent summer flow of San Antonio

*

Creek indicates a long period of carry-over, extending from one season to 

another or perhaps longer.

The bedrock throughout the greater part of the San Dimas and Dalton 

Creek Basins is a soft, well-disintegrated, and partly decomposed darkcolored schist with occasional areas of unaltered granite. The formation 

weathers to rounded ridges, broad canyons, and moderately steep slopes. 

The surface mantle is a granular and porous soil containing many partly 

disintegrated grains of quartz and feldspar and a small amount of rock 

litter. It varies in thickness from 1 or 2 feet on the slopes to 20 feet 

or more on the rounded ridges and in the flat areas. Observations in 

road cuts and other places where the subsurface material is exposed show 

that the soil mantle merges almost Imperceptibly into the shattered, welldisintegrated, underlying bedrock. There are practically no accumulations 

of talus, very few exposures of rock, and most of the area included in 

the two basins is covered with a moderate to heavy growth of chaparral.

The amount of runoff from rain falling on this type of watershed depends in a large measure on the rate of rainfall and on the amount of 

antecedent precipitation. Although the degree of porosity of the mantle 

is high, its rate of absorption is necessarily limited by the small pore 

openings and does not approach that prevailing in the coarse rocky soils 

of other drainage areas. Drainage likewise takes place slowly. Light to
334 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

moderate rains will seldom yield an appreciable amount of runoff unless 

they have been preceded during the season by an average or greater than 

average amount of precipitation. The floods of 1914, 1916, and 1938 show 

an aggravated stage of these unfavorable conditions, an intense storm of 

several hours duration occurring in a season of unusually high antecedent 

rainfall. Under these circumstances, the porous but relatively impermeable subsoil and disintegrated bedrock were probably near saturation 

before the storm occurred, and absorption during the rain was limited to 

the available pore space in the top few inches of the mantle. Although 

there was copious stream flow during the storm of March 1938, only a small 

part of it appeared as direct surface flow, as shown by the observations 

of the United States Forest Service on plots in the San Dimas Experimental 

Forest.

The various drainage basins between the San Gabriel and Arroyo Seco 

Canyons are underlain mostly by diorite and granodiorite. Occasional 

narrow belts of schist and gneiss are found closely associated with and 

paralleling the fault lines, but with these exceptions the rock is unaltered and retains most of its original crystalline texture. In most of *

the basins the rock is intensely fractured and disintegrated to a depth 

of several feet. Partial decomposition at the surface has produced a 

granular soil mantle carrying large quantities of rock particles. Some 

of the steepest slopes in the mountain region are found in this area, yet 

there are few exposures of rook, and the slopes are generally covered 

with a medium to dense growth of vegetation. Large accumulations of talus 

are lacking. The main stream channels are generally floored with bedrock 

in the upper reaches but are covered with alluvium near the valley. In 

Arroyo Seco Canyon these deposits form the aquifers for a number of 

springs and seeps. Runoff characteristics in this area are similar to 

those in the San Dimas and Dalton Creek Basins, with the amount of runoff 

depending to a large extent on the rate and duration of the rainfall and 

the amount of antecedent rainfall.

The effects of geologic conditions on the rainfall-runoff relationship are evident in the contrast between this area of granitic rocks and

the area underlain by metamorphic rocks just north of the San Gabriel

< 

River. These two areas receive comparable amounts of rainfall, both have

southward-facing slopes, and the topography is similar, yet owing to the 

difference in the bedrock there is a notable difference in the type and 

thickness of the soil mantle, in the density of vegetation, and consequently in the runoff characteristics. On the other hand, a comparison
PHYSIOGRAPHIC AMD GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 335

of the sane San Gabriel area with the Cucamonga Creek and lower San Antonio Canyon drainage basins, shows a marked similarity in topography and 

surface features and a very close relationship in runoff characteristics. 

These two areas are underlain by metamorphic rocks of the same general 

type*

In addition to the absorption that takes place over the mountain area 

of the frontal drainage basins flood peaks are further reduced by percolation in the extensive cone structures developed at the mouth of each 

stream. Two conditions, however, mitigate against the full influence of 

percolation as a factor first, the short duration of flood flow, and 

second, artificial restriction of the stream channels. Any unfavorable 

alteration of these conditions such as speeding up the flow by diverting 

the stream to lined conduits or further increase in the practice of channel confinement will, by reducing percolation in the coarse gravels of the 

cone, tend to increase the amount of flood water reaching the valley floor.

Lytle Creek

The characteristics of flood runoff in this basin appear to be materially influenced by both the structural formation of the canyon and the 

type of underlying bedrock. The lower part of the main stream and the 

Middle Fork follow the line of the San Jacinto fault, and the upper reach 

of the stream above Glen Ranch follows the line of the Loma Linda fault. 

It is probable that the canyon above Glen Ranch occupies a depressed fault 

slice, although the evidence of a double line of faulting is hidden under 

alluvial fill.

The movement along these faults has been of sufficient magnitude to 

cause unlike formations to appear on opposite sides of the canyon throughout practically its entire length. The long narrow ridge to the northeast 

which forms the divide between Lytle Creek Basin and Cajon and Lone Pine

Creek drainage basins is composed of Pelona schist, a formation which

27 Noble describes as being "composed chiefly of bluish-gray quartzsericite-albite schist but includes beds of chlorite schist, actinolite 

schist, greenstone, quartzite, and limestone". The rock disintegrates 

readily, forming a mantle of fine, compact soil that supports a heavy 

growth of brush. Slopes throughout this area are moderately steep, with 

rounded ridges and shallow washes. There are practically no extensive 

exposures of rock and talus accumulations are almost unknown, but many of
336 FLOODS OF MARCH 1928 IN SOUTHERN CALIFORNIA

the washes show bedrock floors. The upturned edges of the schista may be 

observed In these channels. Southwest of the fault the country rook Is 

largely dlorlte gneiss and granodlorlte. Hetamorphlo types are exposed 

from the mouth of the canyon to a point above Glen Ranch, but northwest 

of this point the predominating rook Is a fine-grained crystalline granodlorlte, the same formation as that found In the headwaters of San Antonio 

Creek. In fact, conditions along the west side of the Lytle Creek Basin 

are similar In many ways to those In the upper San Antonio Creek Basin. 

Heavy accumulations of angular talus cover the lower slopes whereas the 

higher slopes show many areas of thin mantle or bare rook.

The opposite sides of the canyon show a distinct dissimilarity In 

conditions of runoff from rainfall. Although the slopes underlain by the 

Felona schist are well covered, It Is apparent that they would yield a 

high proportionate runoff from Intense storms. The very fine micaceous 

soils have a high porosity and high retention oapaolty but an exceptionally low permeability. Percolation to the subsurface storage would, 

therefore, be extremely slow, and the surface runoff would be Increased. 

On the other hand, the coarse talus accumulations common to the, opposite

sides of the canyon favor absorption of rainfall In large quantities. The *

topographic expression of this dissimilar behavior Is clearly shown In the 

fill above Olen Ranch. Throughout this part of the canyon, where the 

width of the alluvium ranges from about 500 feet to more than a -quarter of 

a mile, the northeast margin of the fill Is 20 to 30 feet higher "khan the 

southwest margin. Moreover the stream channel, which would normally be 

expected to occupy the lowest depression, follows a course near the top 

of the fill close to the schist slopes. The lower depression shows little 

evidence of stream flow, but the higher watercourse Is a wide, much-eroded 

wash. This condition apparently results from high runoff and-movement of 

debris from the schistose slopes, In contrast to low runoff and slight 

erosion from the opposite side. This behavior would probably prevail only 

In storms of high Intensity. Under light to moderate rains, It would appear that the heavy vegetal covering on the schistose slopes would delay 

surface flow long enough to allow percolation of the water to underground 

storage.

In addition to high direct runoff from heavy storms, Lytle Creek also 

furnishes a substantial summer flow. Part of this flow no doubt comes 

from water retained In the extensive talus deposits of the southern slopes, 

but It Is likely that a larger part has Its source In the extensive porous 

gravel deposits of the canyon. These deposits extend through almost the
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 337

entire length of the stream and range In width from a few hundred feet to 

nearly half a mile. All of the tributaries empty on the deposit, and many 

of them have built small alluvial cones flanking the main stream. The 

probable fault-slice structure of the canyon above Glen Ranch appears to 

be especially well suited for storage, as shown by the substantial amounts 

of water that rise to the surface between Glen Ranch and the mouth of 

Middle Fork of Lytle Creek, where the main stream cuts through a block 

separating two lines of faulting. Contributions from the Middle and South 

Forks of Lytle Creek are mainly from talus deposits, as these streams have 

only small amounts of channel gravel. It is likely that a considerable 

part of the early summer flow originates in melting snow on the northeast 

slopes of the San Antonio Peak ridge, percolating through the gravel fill 

of the canyon.

The valleys 28

San Fernando and San Gabriel Valleys, and the west half of the San 

'Bernardino Valley flank the San Gabriel Range on the south, and each of 

the streams draining from the mountain area south of the crest passes 

through one of them in its course to the Pacific Ocean. In topography 

and structure the valleys are slmilar--each represents a depressed segment of the earth's crust buried under deposits of alluvial fill, and each 

has a comparatively flat surface that slopes gently away from the base of 

the mountains. From the standpoint of their influence on the flood flow 

of streams, the important feature of the valley structures is the great 

depth and porous character of the alluvial cones, which occur at the 

mouths of all canyons and washes, and of the widespread valley fill. The 

cones extend in an almost continuous coalescing belt from the mouth of 

Arroyo Seco Canyon to the mouth of Cajon Canyon. Naturally the height of 

the individual cones and the distance they extend into the valley floor 

vary with the size and drainage area of the parent streams, but their internal structure is similar. Coarse gravel and boulders predominate near 

the apexes of the cones, fine silts and clays are the chief constituents 

at their outer edges, and material of Intermediate texture occupies their 

central zones. This distribution, however, is by no means regular, for,

28 See also Mendenhall, W. C., Groundwater and irrigation enterprises in the foothill belt, southern California: U. S. Geol. Survey 

Water-Supply Paper 719, 1908; Eokis, Rollin, Geology and ground-water 

storage capacity of valley fill: California Dept. Public Works, Water 

Resources Div., Bull. 45, 1934.
338 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

as the cones are the result of deposition by streams in all stages of 

flow, there has been constant shifting of deposition zones, with the result that many types and textures of debris are indiscriminately distributed throughout the mass of the cone. This heterogeneous collection of 

debris is, as a rule, very porous, and its effect on flood flow is limited 

by the rate at which water can percolate during the comparatively short 

duration of the flood. Confining the stream to a single channel or otherwise restricting its lateral spread over the cone naturally reduces the 

absorption area, and infiltration ia correspondingly reduced. Distributing the water over the ground, on the other hand, augments percolation.

The coastal plain 29

An intermediate belt of low hills and mountains, including the Santa 

Monica Mountains, the Repetto Hills, the Puente Hills, and the northwestern part of the Santa Ana Mountains, separates the San Fernando, San 

Gabriel, and San Bernardino Valleys from the coastal plain. The Los Angeles, San Gabriel, and Santa Ana Rivers enter this plain through gaps 

cut through the mountainous belt, and each has deposited a low, broad alluvial cone at the southern base of the hills. From the base of the cones 

the surface slopes gradually to the Pacific Ocean as a flood plain broken 

only by occasional hills and low mesas and the isolated San Pedro Hills, 

which rise abruptly at the coast line in the southwestern part. The flood 

plain is about 50 miles long, extending from Santa Monica to Newport 

Beach, and 12 miles wide, spreading from the ocean to the hills.

Oscillations In sea level, together with some differential land movement, have left the surface somewhat uneven. Some areas are well above 

the level of present deposition and are being actively eroded, whereas 

others are below that level and are being aggraded. The higher surfaces 

coincide with segments of the earth's crust that have been uplifted by 

faulting or folding, and the lower surfaces occupy the troughs between 

the uplifted blocks. The Beverly-Newport uplift, extending southeast from 

Beverly Hills to Newport Beach, and the Santa Fe Springs-Coyote Hills uplift, extending from the subdued Santa Fe Springs dome to the much higher 

Coyote Hills, several miles farther east, are the most prominent of these 

areas of uplift. Between them are broad troughs filled with several hundred feet of Pleistocene and Recent alluvium. Where the streams have cut

29 See also Kckis, Rollin, Geology and ground-water storage of valley fill: California Dept. Public Works, Water Resources Div.; Bull. 45, 

1934.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 339

through the uplifted segments, they occupy deep, well entrenched channels, 

but across the troughs, in which the underlying formation is largely alluvial fill, the channels are usually unstable and shallow, most of them 

less than 10 feet in depth. There is considerable evidence to show that 

the streams have, in the past, meandered over a large part of the trough 

area. It is known, for example, that within historical time the Los Angeles River has reached the ocean through Ballona Creek. During the same 

period the San Gabriel River has shifted several times between its present 

channel, the bed of the Rio Hondo, and the former course of the Los Angeles River. The Santa Ana River, also, has occupied several channels 

within an area extending from Anaheim Creek to Newport Bay. Thus the 

lower part of the coastal basin is in reality a flood plain fed by the 

flows of these rivers, and in times of high flood discharge it is not unusual to find free intermingling of their waters in a sheet spreading 

across the lowlands between Anaheim, Nigger Slough, and the ocean.

Before the arrival of man and the restrictions he imposed on the 

streams by building various bridges, dikes, and other confining structures, 

it is probable that none of the streams had stable channels but that they 

meandered over the wide flat plains, as in fact, they do today in places 

where natural and artificial channels are inadequate to carry the runoff.

In the coastal plain conditions favoring the infiltration of .water 

to underground storage are less favorable than in the upper Santa Ana, 

San Gabriel, and San Fernando Valleys. The material making up the alluvium represents the outwash from small streams draining the predominantly 

sedimentary formations of the surrounding hills plus contributions of fine

debris from the three letter rivers. As a consequence, the channel bottoms are covered with fine, f poorly assorted gravel and sand that includes

a substantial proportion of clay and silt. Much of the surrounding area 

is covered with a surface mantle of heavy clay soil. Under these conditions it is apparent that the capacity for absorbing flood water is 

limited and that the greater part of the water must escape through some 

channel to the ocean.
340 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Santa Clara. Ventura. Santa Ynez, and Santa Maria drainage basins z ®~

The basins of the Santa Clara, Ventura, Santa Ynez, and Santa Maria 

Rivers differ materially in geologic structures and rock types from those 

of the streams that drain from the San Gabriel Range. Basin characteristics, including shape, slope, and topography, as well as mantle covering 

and vegetation reflect this difference. The influence that such factors 

exert on flood runoff from rainfall is likewise shown to some extent.

The country rock of the area is .predominantly sedimentary. Small 

outcrops of igneous and metamorphic rocks are found along the west edge 

of the San Gabriel Range in the headwaters of the Santa Clara River, and 

again along the foothills of the San Rafael Range, reaching from Zaca 

Creek, southwest of Lookout Mountain, to the neighborhood of Little Pine 

Mountain, but these are comparatively unimportant in their effect on flood 

runoff. The exposures of extrusive andesite and basalt found in the Santa 

Susana Mountains and the western part of the Santa Monica Mountains are 

too limited in areal extent to have any appreciable effect on the rainfallrunoff relation in the area. Of the sedimentarj rocks, sandstone, conglomerate, and shale predominate, and impure limestone and siliceous shale 

occur in smaller amounts. For the most part, the shales weather to 

rounded hills with gentle slopes, and the harder sandstones, conglomerates, 

and siliceous shales appear as steep ridges and cliffs. The mantle covering is largely residual and varies in thickness and texture with the slope 

of the terrain and the type of the underlying formations. Sandstones and 

conglomerates weather to coarse porous mantles, shallow on the steep

slopes and thicker on the gentler ones, but shale forms an almost Imper-

 -ijfc 

vious, compact covering on any slopes. The vegaflBf growth reflects, to a

great extent, the underlying formation. The sandy soils support a heavy 

cover of chaparral, especially on the protected northern slopes of the 

mountains, but the shaly soils are usually entirely barren or have.only a 

sparse growth of short grass or stunted sage. Between these extremes are 

variations of all types of cover and vegetation, depending on the proportion of sand or shale in the soil, the direction of slope, and the 

availability of water.

30 See also Eldridge, G. H., and Arnold, Ralph, The Santa Clara Valley, Puente Hills, and Los Angeles oil districts, southern California: 

U. S. Geol. Survey Bull. 309, 1907; Arnold, Ralph, Geology and oil resources of the Summerland district, Santa Barbara County, Calif.: U. S, 

Geol. Survey Bull. 321, 1907; Arnold, Ralph, and Anderson, Robert, Geology and oil resources of the Santa Maria oil district, Santa Barbara County, 

Calif.: U. S. Geol. Survey Bull. 322, 1907; and Ke»r, W. S. W., Los Angeles 

to Santa Barbara: 16th Internat. Geol. Gong., Guidebook 15, pp. 48-68, 

1932.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 341

The structural features of the area under discussion differ considerably from those of the San Gabriel Range. Uplift in the San Gabriel 

Range occurred along fault lines, and the massive igneous and metamorphic 

rooks yielded by fracture rather than folding, the fractures being distributed through the mass of the mountain block in the form of innumerable 

joints, faults, and fissures. The sedimentary country rook of the area 

northwest of the San Gabriel Range yielded to mountain-building forces 

mainly by folding, with faulting of secondary importance. As a result of 

this action a series of east-west trending folds have been developed, 

these folds determining the outline of the characteristic parallel mountain ranges and their intervening valleys. In this pattern the valleys 

generally occupy the synclinal troughs, and the mountains represent the 

anticlinal crests. The pattern has been modified somewhat by differential 

erosion and, in some small areas, by faulting, but in general the drainage follows the structural outline. For the most part, the main streams 

flow westward, following the synclinal troughs, and their tributaries 

enter at right angles, having cut deep, narrow canyons across the upfolded mountainous areas.

Relation of rainfall and runoff to geology

Whatever effect geologic formations have on runoff from rainfall depends on the amount of water that can be absorbed by the surface mantle 

and the pervious parts ,of the underlying bedrock and the rate at which 

the absorption proceeds. The topography and the thickness, texture, and 

composition of the mantle are the principal factors affecting this relationship, and all are the result of geologic processes.

The sedimentary rocks of this area have yielded to deformation by 

folding. The process required a long period of time, during which geologic forces were constantly being applied and readjustments in the rook 

structure were continually taking place. Both the nature of the change 

and the plastic character of the deeply buried sediments were unfavorable 

to the fracturing and associated disintegration such as took place in the 

San Gabriel Range. Consequently, the country rook of the area is characteristically impervious, and percolation of rainfall is therefore limited 

to the porous areas of the surface mantle and to the alluvial fill of the 

river valleys. In areas covered by a deep sandy mantle little runoff 

from rainfall is to be expected. The heavy growth of vegetation usually 

found on such areas stimulates both the percolation and the retention of
342 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

water. On the other hand, rock outcrops favor complete runoff from rainfall, and shaly areas, with their impervious clay mantle and sparse 

vegetation, are almost aa effective in preventing the percolation of rainfall. Coarse valley fill favors percolation from both rainfall and stream 

flow, but with finer textured fills percolation is less effective. The 

proportionate acreage of the different types of rock and surface cover 

found in the various areas will determine the characteristics of the 

rainfall-runoff relationship.

Santa Clara River

The Santa Clara River occupies a somewhat modified structural depression that extends westward from the west flank of the San Gabriel Range 

to the Pacific Ocean, a distance of 75 miles. Its headwaters are on the 

western edge of the San Gabriel Mountains, but most of its drainage area 

lies north of the stream, between Antelope Valley and Pine Mountains. 

All of its larger tributaries, including Castaic, Piru, Sespe, and Santa 

Paula Creeks, named from east to west, drain from the north and flow in a 

general southerly-direction through tortuous courses that have been determined in part by rock structure and in part by erosion. Their canyons 

are deep, many of them cliff-bound, and almost their entire drainage 

basins are steep and rugged. The mountainous parts of their basins are 

generally covered with a fairly thick growth of chaparral, but in the 

foothills vegetation is sparse.

Both the Santa Clara Valley and the lower parts of its tributary 

valleys are floored with alluvium. These deposits range in width from 

half a mile to 3 miles in the main valley, and from a few hundred feet to 

half a mile in the valleys of the side streams. The texture and porosity 

of the fill vary according to the locality; deposits in the upper part of 

the main stream channel consist principally of clean coarse gravel and 

sand derived from the igneous and conglomerate formations common to the 

headwater area, whereas those in the lower part of the main channel and 

in the tributary streams include sand, clay, and silt eroded from the surrounding fine-textured sedimentary rocks. The depth of the fill ranges 

from a few inches along the edge to more than a hundred feet in the central areas. At a few places in the channel the deposits are interrupted 

by exposures of bedrock. One such exposure occurs in the main stream 

about 3 miles east of Piru Creek and forms the area of rising ground water 

reaching upstream to the mouth of Castaic Creek. Another occurs between 

Filmore and Santa Paula, forming a similar but smaller area of rising 

ground water.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 343

It is evident that only In certain reaches of the stream channel, 

that Is, above the mouth of Castalc Creek and between the bedrock exposures east of Plru and the mouth of Sespe Creek, are conditions favorable 

for an appreciable reduction of flood flow by percolation to the alluvial 

fill. The fineness of the alluvium In the lower section of the valley 

and In valleys of the tributaries makes It unfavorable to rapid percolation* and, naturally, areas of rising water would have no capacity for 

additional storage.

The bedrock of the Santa Clara Basin Is sedimentary throughout, except on the northwest slopes of the San Gabriel Mountains. In this 

locality It Is igneous, predominantly anorthosite Intruded by many dikes 

of dark-colored diabase, and conditions are similar to those in the upper 

Tujunga and Pacolma drainage basins. The surface features are favorable 

for the absorption of rain only in small amounts, and when precipitation 

Is heavy copious runoff Is to be expected. The rock-floored gullies and 

severely eroded washes are evidences of the large runoff from the storm of 

March 1938.

In the part of the basin that lies above Piru Creek the country rock 

consists of thick deposits of conglomerate and sandstone with lenses of 

variegated shale and fine-grained sandstone. These beds have been thrown 

into monoclines and more complex folds. Over much of the area east of 

Castaic Creek they crop out as a series of more or less parallel hogback 

ridges, with massive resistant conglomerate or sandstone strata occupying 

the crests. Dip slopes are commonly entirely barren. Between Castalc and 

Plru Creeks the beds have been thrown Into a number of eastward-trending 

folds that appear to have had some influence on the topography. Broad 

ridges alternate with open stream valleys, and the slopes are moderate.

The rocks weather slowly to form a shallow soil mantle that is sandy 

and filled with rock litter where it overlies sandstone or conglomerate, 

but dense and Impervious where it Is derived from shale. Brush is generally sparse, but much of the area is covered with a' fair growth of grass 

and desert annuals.

The bedrock of the area Is somewhat pervious, a few wells derive 

small flows of water from some of the more porous strata, and It is possible that some rainfall percolates to considerable depth. The amount 

appears to be relatively small, however, and it Is believed that absorption is limited mainly to areas covered with a porous soil mantle.

454720 0-42-23
344 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Plru Creek

The formations underlying the Plru Creek Basin are somewhat finer In 

texture than those Immediately to the east. They consist mainly of shale, 

siliceous shale, and fine-grained sandstone with occasional beds of conglomerate. Structural deformation has cast the beds Into a great number 

of more or less parallel folds; some of these are broad with the beds Inclined at a low angle, and others are squeezed, so that the beds often 

stand nearly vertical. Plru Creek has out across the prevailing trend of 

these folds, and Its tributaries drain through canyons that are more or 

less parallel to them.

Slopes along the lower 15 miles of the creek and Its tributaries are 

exceptionally steep. A shallow sandy and rocky soil mantle, In most 

places not more than a few Inches thick, Is the prevailing type of cover 

and a considerable part of the area shows bare rock slopes. Many of these 

appear to be due to small landslides that were generated during the storm 

of March 1938. Nearly all the steeper washes are eroded to bedrock. Soilcovered spots support a moderate growth of brush and grass. The flnetextured, rather thin-bedded rooks show little tendency to break Into 

spalls or large fragments, and consequently there are no talus deposits. 

 The topography In the upper reaches of the drainage basins Is more 

mature; the canyons open to valleys, the slopes are moderate, and there 

are few areas of exposed rock. The soil mantle, although somewhat thicker 

than on the steeper slopes, Is relatively shallow, but'the vegetal coverIng Is moderate to heavy. With the exception of rock exposures, surface 

features appear to be favorable to the absorption of moderate amounts qf

rainfall. However, as absorption In this basin Is definitely limited to

/ 

the surface mantle because of the impervious character of the bedrock, *

heavy rains of long duration are likely to furnish a proportionately 

higher runoff, than In the San Gabriel Range, but probably not so high as 

In the neighboring Sespe Creek Basin.

Sespe Creek

Features that favor the absorption and retention of rainfall are probably less prevalent in the Sespe Creek Basin that in any similar area in 

the Santa Clara drainage basin. The type of bedrock, the character and 

small extent of the surface mantle, and the structural arrangement of the 

mountain mass appear to be responsible for this condition. The bedrock 

throughout the larger part of this creek basin is dark brown or
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 345

chocolate-colored and is composed of fine-grained sandstone interbedded 

with shale and, in a few places, deposits of conglomerate. These beds 

are easily recognized and are known to geologists as the Sespe formation. 

In the lower part of the drainage basin, between Sespe and Little Sespe 

Creeks, the beds are mainly thin and shaly, but in the higher parts of the 

basin they become thick and massive. In both localities, however, the 

rocks are dense and compact, .and appear to be practically impervious to 

water. Folding and faulting have caused many variations in structure, 

and in most areas the beds dip at high angles. Dip slopes are prevalent, 

and many of them have been eroded until they are entirely barren of soil 

or vegetation. In the plateau section, between Sespe and Little Sespe 

Creeks> it is estimated that as much as 25 percent of the area has been 

denuded of soil; in other sections the percentage is much less.

The Sespe formation weathers to a shallow fine-textured soil mantle, 

somewhat sandy in most areas but tight and clay-filled in localities underlain by shaly deposits. The bedrock shows practically no weathering 

or disintegration below the soil mantle, and extensive talus deposits are 

lacking. Vegetation on soil-covered areas is, as a rule, heavy. The 

Sespe Creek channel is filled with alluvium below the junction of Sespe 

and Little Sespe. Creeks, but above that point both streams and most of 

their tributaries contain only shallow fills of debris or have been eroded 

to bedrock.

The unusually high percentage of bare rock slopes in the Sespe Creek 

Basin is naturally reflected in the runoff characteristics of the stream, 

since these slopes furnish complete and direct runoff from storms of practically any type or intensity. Much of the remaining soil-covered area 

has characteristics that are unfavorable to extensive absorption. The 

soil covering when dry, appears to be open and porous, but close examination reveals that most of it contains enough clay to render it nearly 

impervious when wet. This condition prevails on the plateau between Sespe, 

and Little Sespe Creeks and was noted also on the north slopes of the 

Topatopa Mountains. Once this material has been thoroughly soaked at the 

surface by antecedent rains, its capacity for absorbing additional quantities of water is greatly reduced. Even in areas where the soil covering 

is highly porous, the retention of rainfall is limited by the shallowness 

of the mantle and the compact, impervious nature of the bedrock.
346 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 

Other parts of Santa Clara drainage basin

Conditions over the remainder of the Santa Clara drainage basin, which 

includes the north-facing slopes of the Santa Suaana Mountains, Oak Ridge, 

South Mountain, and the south-facing slopes of Sulphur Mountain, are somewhat more favorable to retention of rainfall, and comparable rains are 

therefore not likely to show as high a proportion of runoff as on Sespe 

Creek. The bedrock over the area is of the same type and character as 

that in the Piru and Sespe Creek Basins, but the structural features are 

not so sharply defined and the slopes are less steep. Barren dip slopes 

are lacking, and although there are a few patches of exposed rock, they 

are fewer than in the Piru Creek Basin. The soil mantle, although relatively shallow, is generally sandy and porous. Brush is, as a rule, sparse, 

especially on north-facing slopes, but the surface is well protected during the winter by a heavy growth of native grass. The absorptive capacity 

of the cover appears to be sufficient to enable it to retain practically 

all the rainfall from light or moderate storms, and the only runoff likely 

to appear under these conditions is from the small areas of exposed bedrock. Intense and protracted rains, on the other hand, are likely to 

furnish heavy runoff.

Ventura River

The Ventura River and its chief tributaries, Coyote Creek and Matilija 

Creek, drain an area that includes the OJai Valley and the mountainous 

region to the north, west, and east. Ojai Valley is an alluvium-filled 

structural depression, resulting partly from fault action and modified by 

erosion, measuring about 12 miles from east to west and 2 miles from north 

to south. Streams from the mountains have built up steep alluvial cones 

along the north margin of the valley, and from the base of these cones the 

valley floor slopes gradually toward the southwest. Both the cones and 

the valley fill are important as sources of ground water, and their capacity for storage of additional water is usually sufficient to insure the 

absorption of the ordinary runoff of streams and washes draining across 

them.

A comparatively low but rugged range of hills lies between the Ojai 

Valley and the Pacific Ocean. This range is a part of the complex, upfolded mass that extends west from Piru Creek to the ocean, and its sedimentary bedrock is of the same age and approximately the same character 

as that found in the Piru and Sespe Creek Basins. Ventura River has cut
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTISG FLOOD RUNOFF 347

directly across this range, forming a wide but steep-aided canyon. Coyote 

Creek, entering from the west, and Canada Larga, from the east, are the 

largest tributaries. The lower parts of the basins of these streams, together with the Ventura Valley, are graded and filled with alluvium. They 

provide considerable underground storage.

The largest and most important part of the Ventura River Basin, from 

the standpoint of water production, lies to the northwest of the Ojai Valley. It is drained by Matilija Creek and its tributaries. This area 

includes the northward-facing slopes at the western end of the Santa Ynez 

Mountains and the southward-facing slopes of Ortega Hills.

The country rock in the area is of sedimentary origin and consists 

of interstratified shale, sandstone, and conglomerate, all so veil consolidated that it may be considered to be impervious. The beds have been 

folded and tilted, though probably less than in the lower reaches of Piru 

and Sespe Creeks, and over much of the area they appear as a succession 

of sharp ridges and canyons, with massive resistant strata forming the 

ridge crests and softer beds flooring the valleys. Slopes are generally 

steep but as a rule are not precipitous except in occasional stretches 

along some of the steeper, narrower canyons.

The soil mantle is residual and varies in texture and composition according to the nature of the parent rock. Sandy types seem to prevail. 

The covering is rarely more than 1 or 2 feet thick, but it is widespread 

and there are only occasional small areas of exposed bedrock. Vegetation 

is usually heavy on the north-facing slopes but scattered and sparse in 

other places. Clay soils overlying shale beds can generally be distinguished by their sparse vegetal covering.

As impervious bedrock underlies the greater part of the Ventura River 

Basin, the absorption of rainfall will be restricted to the soil mantle 

of the mountain section and the alluvial fill of the stream and valley 

areas. As the capacity of the soil to hold water is necessarily small 

because of its shallowness, it is evident that only light or moderate 

rainfall will be absorbed. Storms of greater intensity and longer duration must eventually yield the greater part of their precipitation as 

runoff, and this will appear in the valley and in the alluvium-filled sections of the streams. The most favorable locality for absorption of 

either ordinary or flood runoff is along the Ventura River where it 

crosses the Ojai Valley, but storage in this area is limited by the high 

ground-water level that usually prevails in the lower parts of the valley.
348 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Measurements made by the State Division of Water Resources 31 indicate 

that considerable rainfall may percolate to ground storage during earlyseason storms, but that the amount dwindles rapidly as later storms tend 

to fill the available storage. Storage in the alluvial belts found along

the Ventura River between Ojal Valley and the ocean and the lower parts

 

of the basins of the larger tributaries, notably Coyote, San Antonio, and

Santa Ana Creeks and Canada Larga, is limited by the relatively small extent of the deposits.

The limited storage available in both the mountain and valley areas, 

would indicate a relatively high flood runoff for the Ventura River.

Santa Ynez River

The Santa Ynez River occupies a structural trough that trends 

slightly north of east and follows the north flank of the Santa Ynez Mountains. Besides the north slope of these mountains its drainage basin 

includes the southwest slope of the eastern part of the San Rafael Mountains, the south slope of the Purisima Hills, and the wide valley areas 

around Santa Ynez and north of Loppoc. Toward the south the slopes rise 

steeply in a series of steps to the crest, of the Santa Ynez Mountains, 

but toward the north they rise gradually from the terraces and sand hills 

west of the Santa Ynez Valley, becoming steeper,with pronounced ridges and 

sharp canyons, as they merge with the south slopes of the San Rafael Range.

In its upper reaches the river flows through a well-defined canyon, 

and has a gradient of about 125 feet to the mile. Throughout most of tills 

stretch there is a little fill on the canyon floor and that only in thin 

deposits. Beginning at a point east of Santa Ynez and extending to the 

coast, the gradient drops to 25 feet to the mile and the valley opens to 

the north over wide terraces. In this stretch deposits of recent alluvium 

underlie the river channel.

The north-facing slopes of the Santa Ynez Range carry a fairly heavy 

growth of vegetation, but north of the river the covering is limited to a 

sparse growth of brush and grass, with occasional patches of more luxuriant vegetation in shaded and protected places.

The rock of the Santa Ynez Range consists of marine sediments, Including sandstone, shale, and conglomerate, with small areas of limestone. 

Sandstone occurs in the foothills, shale in the intermediate belt, and 

sandstone and conglomerate at the crest of the range. Both the sandstone

31 Conkling, Harold, Ventura County investigation: Bull. 46, p. 

1934.
PHYSIOGRAPHIC AND GEOLOGIC FEATURES AFFECTING FLOOD RUNOFF 349

and the shale are well consolidated, so that the absorption of rainfall 

would take place only In the soil mantle.

Terrace deposits of considerable extent occur In the Santa Ynez Valley at Its coastal end, west and north of Lompoo, and throughout Its 

middle and upper reaches. The deposits consist of a veneer of sand and 

gravel, usually not more than 25 feet thick, normally soft and porous but 

In places compacted and cemented. Where they are soft and porous, the 

deposits are capable of absorbing the rainfall from all but the most Intense storms. These deposits and the underlying formations probably also 

act as reservoirs for water percolating from the river, though of course 

this percolation can take place only In the Immediate vicinity of the 

stream.

The bedrock In the Purlalma Hills and In small areas In the foothills 

of the San Rafael Range includes thick deposits of dlatomaoeous shale. 

This shale also underlies much of the terrace deposits of the river valley. 

Where the shale has not been altered by close folding or siliceous cementation it has a porous texture favorable to absorption of water. Although 

definite information is lacking, it appears that in a large part of the 

Purlalma Hills area and a smaller part of the San Rafael district the exposed bedrock is of this character. Areas underlain by slllolfled and 

folded strata are likely to yield complete runoff from any but the lightest storms.

The remaining areas, in the San Rafael part'of the Santa.Ynez River 

Basin are underlain by sedimentary rooks ranging in texture from coarse 

sands and conglomerates of fluvial origin to well-compacted fine sands and 

shale of marine origin. The harder beds prevail over the higher parts of 

the area, and the softer beds occupy the foothill area near the river. A 

narrow belt of old crystalline rook half a mile to a mile in width and 

several miles in length strikes southwest from the head of Llsque Creek.

Owing to the diversified types of bedrock and mantle found within 

the Santa Ynez River Basin any relation between flood runoff and geologic 

conditions is indefinite. Although the exposures of Impervious bedrock 

are limited in their areal extent, medium rains are likely to provide almost complete runoff from these areas and local floods are to be expected. 

Except in the more Intense and widespread storms, such runoff ehould be 

largely absorbed by the more porous sands and the valley fill.
350 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Santa Maria River

The Santa Maria Valley is a broad triangular area bounded on the 

southwest by the Casmalla and Solomon Hills and on the northeast by the 

San Rafael Mountains. The. Cuyama and Sisquoc Rivers with their tributaries drain the San Rafael Mountains and debouch on the valley floor to 

form the wash of the Santa Maria River. The Santa Maria flows only in 

times of flood. Streams from the Solomon Hills also debouch on the valley 

floor but seldom, if ever, reach the river. The runoff from Casmalia 

Hills is largely intercepted by Ouadalupe Lake.

The valley is a wide flood plain, the interior part of which is 

floored with thick deposits of Recent alluvium. Along the edges of the 

valley are terraces that fringe the San Rafael Mountains on the northeast 

and rise gradually to the Casmalia and Solomon Hills on the southwest. 

The alluvial fill consists mainly of coarse gravel and sand, with some 

finer sediments near the ocean, all capped by fine-textured soil. The 

fill is favorable to water percolation and storage and is the source of 

irrigation water used in the extensive agricultural development of the 

valley. The terrace deposits are similar to those found along the Santa 

Ynez River, and percolation in them is limited to the more porous areas.

The principal source of supply for the Santa Maria River is the runoff from the southwest slopes of the San Rafael Mountains. The bedrock on

these slopes includes a belt of thin-bedded siliceous shale paralleling

 

the valley along the foothills and, contiguous to it on the northwest,

older sedimentary rocks, mainly sandstone, conglomerate, and shale. The 

beds are considerably folded, and in many places their thinly mantled 

edges appear at the surface. A wide belt which follows the crest of the 

range, is made up of a thick series of alternating thin-bedded darkcolored shale and more massive sandstone. These beds are not so strongly 

folded as the younger formations, but in places they are steeply upturned.

In general, flood flows in the Santa Maria River originate on the 

southwest slopes of the San Rafael Mountains. The higher mountains have 

the greatest rainfall, and the thin-bedded shales and the hard, massive 

sandstone found In this area are least favorable to water absorption; the 

shallow soil mantle, especially where it overlies shale, is itself largely 

Impervious, and the underlying rock is almost completely so. Softer parts 

of the siliceous shale favor absorption on low to moderate slopes, and 

these areas probably do not contribute runoff except in severe storms.
FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 351 

RAINFALL, RUNOFF, AND RETENTION

The amount of runoff that reached stream channels during the flood 

of March 1938 and the degree to which this runoff was concentrated with 

respect to time were governed mainly by the rates of rainfall, absorption, 

and retention during the storm period and by the amount of water in the 

ground at the beginning of the storm period. The antecedent rainfall, to 

the extent that it was filling the natural surface and subsurface storage 

at the beginning of the storm, had an important effect on the runoff and 

on the maximum rates of discharge, as continuing rains not accompanied by 

a corresponding draining out of the infiltrated water may result in-a condition approaching saturation. Any decrease in the ability of the ground 

to absorb the storm rainfall, especially during periods of heavy precipitation, would tend to increase the flood runoff.

Practically all the major floods of record in southern California 

have been preceded by about 8 inches of antecedent rainfall within a period of a few weeks, and the floods of March 1938 were no exception.32 

In February 1938, as shown in table 8 on page 82, there had been copious 

rainfall, in excess of normal, throughout southern California, and as a 

result a part of the absorptive capacity of the drainage basins was utilized when the storm period began.

Antecedent precipitation and retention

The retention in a drainage area is the difference between the rainfall and the runoff (including water losses), accumulated from an 

appropriately selected time of beginning. It may serve as an index of 

the state of the ground-storage capacity in the area immediately before a 

storm and hence of the effect of antecedent pre'cipitation on direct runoff from the storm. To illustrate this point a study of retention has 

been made in Strawberry and Santa Anita Creek Basins for the rainy seasons 

of 1925-26, 1926-27, and 1937-38. Strawberry Creek, with a drainage area 

of 8.6 square miles above the gaging station, is in the San Bernardino 

Mountains, and Santa Anita Creek,with a drainage area of 10.5 square 

miles, is in the San Gabriel Mountains.

In this study it is necessary to make a distinction between gross 

retention and net retention. The gross retention in a drainage area is 

the difference between the rainfall and the runoff from a given time, as

32 Lynch, H. B., The history of floods In California; Am. Geophys, 

Union Trans., 1939.
362 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

for example, the beginning of the rain? season, and exceeds in amount the 

actual water in ground storage in the drainage area by the amount removed 

by evapo-transpiration or other depletion. For Strawberry and Santa Anita 

Greek Basins, the Influence of ground-water flow to or from the drainage 

area at the point of measurement is assumed to be negligible. Moreover, 

the phreatlc divide is assumed to conform to the divide of surface drainage.

In southern California the short mild winters with considerable 

moisture are more favorable to the growth of vegetation than the long hot, 

dry summers. Consequently, In this area, unlike mountain areas in many 

other States, there is considerable winter evaporation and transpiration. 

The average annual evapo-transpiration is estimated to range from 15 to 

18 inches in the valley areas to 20 to 25 inches in the highest mountain 

areas. The type of vegetation and hence the transpiration would seem to 

bear a relation to the available water supply. 33

Although there has been some investigation of evapo-transpiration 

losses, the data are not sufficient for satisfactory evaluation of net 

retention. For this reason and because of the possible influence of 

ground-water flow to or from the basin, any determination of net retention must be subject to some speculation.

As a rough approximation for use in the present illustration, it is 

assumed that, in the drainage areas considered, the rate of transpiration 

Is 1 Inch per month in winter, and, on the basis that transpiration is 

largely a function of solar radiation, that this rate increases to 2 

inches per month in summer. The rate of loss will be modified somewhat 

by the amount of water available at the surface, and therefore after a 

heavy storm it may exceed the estimated monthly rate. In this study the 

evaporation loss following a heavy storm has been assumed to be 0.5 inch 

for each storm period. If the rainfall for the entire storm period was 

less than 0.5 Inch, the entire amount is assumed to have been lost.

The average rainfall for Strawberry Creek Basin is based on the records at Squirrel Inn (altitude, 5,300 feet), which is within the drainage 

basin, and at San Bernardino (altitude, 1,048 feet), which is juet south 

of the mouth of the canyon of Strawberry Creek. The average rainfall for 

Santa Anita Creek Basin is based on the records at Mount Wilson (altitude, 

5,850 feet) and at Santa Anita Canyon ranger station (altitude, 1,950 

feet), both of which are within the drainage basin.

33 Sonderegger, A. L., Water supply from rainfall on valley floor, 

Am. Soc. Civ. Eng. Trans., vol. 94 p. 1263, 1930.
RAINFALL, RUNOFF, AND RETENTION 353

Table 25 shows for Strawberry and Santa Anita Creek Baslna the rainfall, the runoff, and the net retention, estimated aa explained above, for 

perioda preceding the major storms and during the major atorm for the 

rainy aeasons of 1925-26, 1926-27, 1937-38. The rainfall for the major 

storm period as given in this table la the actual rainfall minus the 

eatimated amount of water loat by evaporation during the atorm. The flood 

runoff for these three years was the highest in about 20 years of atreamflow records at these two gaging stations. The eatimated net retention 

in each basin, although subject to inaccuracy, aa previoualy explained, is 

an index of the soil moisture in that basin before and after the major 

storm periods.

2able 25.- Net retention in Strawberry and Santa Anita Creek Basins for the rainy 

seasons 1925-26, 1926-27, and 1937-38

Basin, stream, 

and season

Santa Ana River

Strawberry Greek

near Arrowhead

Springs

1925-26

1926-27

1937-38

Los Angelas Rivei

Santa Anita Creek

near Sierra

Hadre

1925-26

1926-27

1937-38

Period preceding major storm

Date

Deo. 1 to

Mar. 30

tarn 21 to

Feb. 10

Deo. 11 to

Feb. 25

Dec. 1 to

liar. 30

Dec. 25 to

Feb# 10

Dec. 5 to

Feb. 26

Rainfall

14.68

11.09

20.65

14.48

13.07

24.68

Evapoloes 

(a)

7.73

6.08

6.71

8.27

6.06

7.30

Runoff

1.28

.93

2.10

1.07

.90

2.70

ffet 

retention

5.67

4.08

11.84

5.14

6.11

14.68

Major storm period

Date

Apr. 1 to

10

Feb. 11 to

20

Feb. 25 to

liar. 3

Apr. 1 to

15

Feb. 11 to

liar. 5

Feb. 27 to

Mar. 3

Rainfall 

(b)

18.76

15.62

16.39

16.23

16.62

24.60

RunOff

1.97

2.83

5.24

3.90

4.60

11.11

Net

retention

16.79

12.79

11.15

12.33

12.02

13.49

Sotal 

net 

retention

22.46

16.87

22.99

17.47

18.13

28.17

a Estimated evaporation from rainfall and transpiration.

b Adjusted for estimated evaporation losses during the period.

The retention and therefore the runoff reeulting from a given storm 

depend fundamentally on the following factors:

(1) The retention in the basin from antecedent rainfall, which 

serves to occupy some of the available storage and thus to decrease the 

absorptive capacity of the soil.

(2) The amount and rate of storm rainfall.
354 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The data In table 25 Indicate that In Strawberry Creek Basin the retention preceding each of the three storm periods listed was of about the 

same magnitude as In Santa Anita Creek Basin. In Strawberry Creek Basin, 

the rainfall during the 1926 and 1927 storm periods averaged about the 

same as for 1938, but the retention In this basin prior to the March 1938 

storm was 11.84 Inches, as compared with 5.67 and 4.08 Inches during the 

earlier seasons, and as a result the proportion of the storm rainfall appearing as runoff was greater than for the two earlier storms.

In Santa Anita Creek Basin the retention preceding the storms of 

1926 and 1927 was 5.14 and 6.11 Inches, respectively. The rainfall during each of these two storm periods was about the same and averaged about 

16.4 Inches; the runoff averaged 4.3 Inches, adding an Increment to the 

basin retention that averaged 12.2 Inches, giving a total average retention of 17.8 Inches. However, the net retention In the basin preceding 

the storm of March 1938 was 14.68 Inches, which was about 9 Inches more 

than the average for the earlier years. As a result of 24.6 Inches of 

storm rainfall there was a runoff of 11.11 Inches, adding an Increment to 

the basin retention of 13.49 Inches, or an average of only 1.3 Inches mom 

than resulted from the materially lighter storms of 1926 and 1927* The 

runoff that resulted from the storm of March 1938 was correspondingly 

greater than that from the 1926 and 1927 storms, and seemingly for two 

reasons greater antecedent retention and greater storm rainfall.

Figures 37 and 38 show the precipitation, runoff, gross retention, 

and net retention, estimated as Indicated above, for Strawberry and Santa 

Anita Creek Basins, for the rainy seasons of 1926-27 and 1937-38.

In the "New Year's storm of 1934," at Hoegee's camp, in the headwaters of Santa Anita Creek, 19.20 Inches of rain fell In 2 days, but the

maximum discharge at the gaging station was only 54 second-feet per square 

mile. This low runoff is explained by the relatively light antecedent 

precipitation of only 13.59 Inches during the preceding 3 months, much of 

which had already been lost by transpiration and evaporation, thus affording a relatively large retention capacity.

One of the outstanding floods of the period of record In southern 

California occurred In January 1916. 34 Analysis of that flood on the San 

Diego River near Lakeside Indicates the outstanding Influence that retention within the basin has on subsequent flood runoff. Prior to January

34 MoQlashan, H. D., and Ebert, F. C., Southern California floods 

of January 1916: Geol. Survey Water-Supply Paper 426, 1918.
RAINFALL, RUNOFF, AMD RETENTION 355

Nov. Da»« Jan. ' Feb. Mar.

Figure 37.- Precipitation, runoff, and gross and net retention on Strawberry Creek

during rainy seasons of 1926-87 and 1937-38.
Precipitation,in inches 
RAINFALL, RUNOFF, AND RETENTION 367

13, 1916, the total precipitation for the season had amounted to an average of 10.02 inches on the San Diego River drainage basin, fully half of 

which is estimated to have evaporated or transpired by January 13. Between January 13 and 21 the precipitation was 16.33 inches, of which about 

4.94 inches ran off, leaving a gross retention from the beginning of the 

storm of 11.39 inches on January 23. During a 7-day storm period beginning January 23, 11.27 inches of rain fell, which was about 70 percent of 

the rainfall in the first storm. The runoff from this second storm was 

about 100 percent', indicating that the limit of storage capacity in the 

ground had been practically reached during the first storm.

The rather large absorptive capacity shown for Strawberry and Santa 

Anita Creek Basins seems to be typical of much of the San Gabriel and San 

Bernardino mountain areas. Additional evidence of absorptive capacity 

can be seen by an inspection of the runoff records subsequent to the storm 

of March 1938. The subsequent period utilized for this study extended to 

September 30, 1938. The detailed records of stream flow subsequent to 

March 10 are given in Geological Survey Water-Supply Paper 861, covering 

stream-flow measurements in southern California for the year ending September 30, 1938. The runoff data for the period following March 10 as 

used or cited in this discussion were obtained from that source.

The runoff of San Antonio Creek Basin near Claremont during the period March 4 to September 30, 1938, was 32.1 inches. During this period 

the rainfall was only about 7.5 inches, of which it is estimated about 

1.5 inches evaporated. The loss by transpiration during the period is 

estimated at about 11.5 inches. On the basis of these records and estimates, and assuming also that the influence of ground-water flow to or 

from the basin at the point of measurement was negligible, there must 

have been a net retention of about 37.6 inches (32.1 + 1.5 + 11.5 - 7.5) 

in San Antonio Creek Basin above the river-measurement station near 

Claremont on March 4. A calculation based on the same rainfall, evaporation, and transpiration, indicates that Mill Creek Basin had about 28.2 

inches in retention on March 4, and Lytle Creek Basin about 30.6 inches. 

If this analysis is correct, these three stream basins showed the ability 

to retain at least 28 to 37 inches of water in subsurface storage. If 

the estimates of evaporation following rains (1.5 inches) and of transpiration from the chaparral cover (11.5 inches) during the period March 4

v 

to September 30, 1938, are too small, the estimate of retention must be

increased accordingly. In order to supply the observed stream flow during
358 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

the period March 4 to September 30 and the estimated evapo-transpiration 

requirements for the same period, it is assumed that there must have been 

in storage prior to the March storm at least 20.9 inches (37.6 inches, 

total retention, minus 16.7 inches, retention from March storm) in San 

Antonio Creek Basin, 10.5 inches in Mill Creek Basin, and 13.5 inches in 

Lytle Creek Basin. To each of these amounts should be added the groundwater storage still retained on September 30, 1938, to obtain the actual 

net retention in each basin prior to the March 1938 storm.

Variations in the geologic structure of the basins of San Antonio, 

Mill,and Lytle Creeks undoubtedly affect the absorption, storage, and 

flow of ground water, and perhaps the position of the phreatic divide in 

relation to the surface divide. Consequently, the results for these tiiree 

streams may indicate a retention that is higher than would be generally 

representative of streams in the region.

For example, the drainage area of Lone Pine Creek is contiguous to 

that of Lytle Creek, referred to above. The retention for the storm period ending March 3, 1938, was 16.83 inches for the former and 17.09 

inches for the latter. (See table 26) However, the runoff March 4 to 

September 30, following the storm, was only 3.1 Inches for Lone Pine 

Creek as compared with 25.1 inches for Lytle Creek. The difference of 22 

inches in runoff indicates dissimilar geologic formations or other conditions that affect the rate at which ground-water storage is released to 

the streams in these basins.

San Diego. San Dleguito, San Luis Rey, and Santa Margarita River Basins

As shown on the isohyetal map, the storm of March 1938 was relatively 

light in San Diego County and flood conditions were not severe. Table 26 

lists for 10 stream-measurement stations in San Diego County the average 

rainfall for the period February 27 to March 3; the runoff in inches and 

acre-feet for the periods February 27 to March 3 and March 4 to 10 and 

also for the maximum 24-hour period; and the difference between rainfall 

and runoff at midnight on March 3 and March 10. The indicated retention 

relates only to the March flood period and does not include retention 

from precipitation prior to February 27. The periods used in table 26, 

as previously indicated in the text, show characteristic phases of the 

March flood.
RAINFALL, RUNOFF, AND RETENTION 359

A'llmlted amount of regulation during the flood period was effected 

by Cuyamaca and El Capitan Reservoirs on San Diego River and Lake Henshaw 

on San Luls Key River. The records for all other streams In San Diego 

County listed In table 26 represent conditions of natural flow.

The average rainfall by basins for the storm period of March 1938 In 

San Diego County ranged from 8.41 to 15.10 Inches, which Is considerably 

less than was recorded during the storm of 1916." The rainfall on San 

Diego River Basin upstream from the gaging station near Santee was 21.4 

Inches during the storm period of January 1916, as compared with only 9.53 

Inches during the storm of March 1938. Likewise the rain on San Luls Rey 

River Basin upstream from OceansIde was 22.6 Inches during the 1916 storm 

and only 11.20 Inches during the March 1938 storm.

The runoff for the different basins ranged from 0.59 to 2.91 Inches 

during the period when It was heaviest, February 27 to March 3. The least 

runoff was In San Diego River near Santee, possibly a result In part of 

regulation at El'Capitan Reservoir, where 12,560 acre-feet, or 0.62 Inch 

depth on the drainage area above Santee, was placed In storage during the 

March flood period. The flood runoff of San Diego River Basin for the 

March storm has been exceeded four times during the period of record, 

1912-38, as follows: January 26-30, 1916 (at Old Town Station), 5.16 

Inches; February 14-18, 1927, 3.54 Inches; December 26-28, 1921, 2.00 

Inches; and April 6-9, 1926, 0.96 Inch.

Table 26 shows that the runoff during the maximum 24-hour period 

represented from 58 to 75 percent of the total storm runoff of February 

27 to March 3, 1938, with the San Diego River Basin near Santee showing 

the greatest concentration and Temecula Creek Basin at Railroad Canyon, 

near Temecula, the least. High concentration of flood runoff with respect 

to time seems to be typical of semlarld areas. The peak discharge rate 

of Santa Ysabel Creek near Mesa Grande was 2.8 times that of the maximum 

24-hour period, which Is the .highest ratio in the entire group. The lowest ratio between rate of peak discharge and maximum 24-hours was 1.4 on 

San Luis Rey River at OceansIde; this may have been due in part to regulation by Lake Henshaw.

35 McQlashan, H. D., and Ebert, F. C. Southern California floods 

of January 1916, U. S. Oeol. Survey Water-Supply Paper 426, 1918.

454720 O - 42 -24
360 FLOODS 0£ MARCH 1938 IN SOUTHERN CALIFORNIA

Table 26.- Rainfall, runoff, and retention 

for selected streams

No. 

on 

pis. 

11,12, 

13

10

12

13

15

16

17

18

19

20

21

27

29

52

33

34

39

40

41

42

43

46

47

48

49

50

52

54

57

60

69

71

72

73

75

Stream and point of measurement

San Diego River Basin

San Diego River near Santee (a)

San Vioente Creek at Foster

San Dleguito River Basin

Santa Ysabel Creek near Mesa Grande

San Luis Rey River Basin

San Luis Rey River near Bonsall (b)

San Luis Rey River at Oceans ide (b)

Santa Marsarita River Basin

Temeoula Creek at Nigger Canyon, near

Temeoula

Temeoula Creek at Railroad Canyon, near

Temeoula

Santa Margarita River near Fall Brook

Santa Margarita River at Ysidora

Murrieta Creek at Temeoula

Santa Ana River Basin

Santa Ana River near Mentone

Santa Ana River near Prado

Mill Creek near Craftonville

Plunge Creek- near Bast Highlands

San Timoteo Creek near Redlands

Strawberry Creek near Arrowhead Springs

Waterman Canyon Creek near Arrowhead

Springs

City Creek near Highland

Devil Canyon Creek near San Bernard ino

Lytle Creek near Font ana

Cajon Creek near Keenbrook

Lone Pine Creek near Keenbrook

Day Creek near Btiwanda

Cuoamonga Creek near Upland

San Jaointo River near San Jaointo

San Jaointo River near Blsinore

Temesoal Creek near Corona

San Antonio Creek near Claremont

Santiago Creek near Villa Park

San Gabriel River Basin

West Fork of San Gabriel River, at floodcontrol reservoir No. 2 near Camp

R ino on

Rogers Creek near Azusa

Fish Creek near Duarte

Sawpit Creek at flood-oontrol reservoir

near Monrovia

San Dimaa Creek, at flood-oontrol reservoir near San Dimaa

Drainage 

area 

(square 

miles)

380

75

58

514

557

319

592

645

740

220

0144

dl,520

42.9

16.9

118

8.6

4.55

19.8

6.16

47.9

40.9

15.3

4.8

10.1

140

717

e!57

16.9

83.8

40.4

6.4

6.5

3.27

16.5

Mean areal 

rainfall 

Feb. 27 

to 

Mar. 3 

( inches )

9.53

8.96

15 ..10

11.46

11.20

8.41

8.51

8.91

9.51

8.42

24.63

13.59

25.86

19.98

11.28

17.34

18.59

19.21

16.51

27.33

20.85

23.14

25.27

25.38

11.14

7.74

10.84

28.58

13.23

23.62

20.83

21.77

23.00

20.71

* Maximum daily mean.

a Runoff not corrected for regulation by Cuyuma and El Capitan Reservoir.

b Runoff not corrected for regulation by Lake Henshaw.
RAINFALL, RUNOFF, AND RETENTION 361

for the period February 27 to March 10, 1938, 

in southern California

Run

Inches

Feb. 27 

to 

Mar. 3

0.59 

1.88

2.91

1.21 

1.10

.92

1.43

1.56 

1.81 

2.14

6.56

1.06 

8.17 

6.70 

.77

5.99 

6.05

5.97 

5.65 

10.24

6.40

6.31 

13.43 

12.14 

2.51

.14 

1.07 

11.84 

2.68

12.06

8.10 

8.70 

7.20

5.69

Mar.

4-10

0.23 

.77

1.26

.44

.51

.26

.25

.89 

.43 

.14

2.01 

.26 

3.94 

2.54 

.02

1.94 

2.39

1.93 

2.33 

3.76

1.21 

.96

3.63 

3.18 

1.26

.43

.21 

3.96 

1.25

3.01

2.45 

2.82 

2.25

1.55

Maximum 

24 

hours

0.44

1.25

1.77

.79 

.77

.68

.83

.96

1.03 

1.48

5.41 

.82 

6.67 

4.74 

.65

4.15 

4.45

4.31 

4.17 

7.69

4.26 

4.59 

9.51 

8.91 

#1.36

.14 

.88 

10.14 

1.80

8.26

4.42 

4.80 

4.57

3.94

off

Acre-feet

Feb.. 27 

to 

Mar. 3

11,890 

7,520

9,030

33,220 

32,850

15,600

45,020

53,610 

71,300 

25,110

50,020 

85,630 

19,180 

6,040 

4,850

2,750 

1,470

6,290 

1,850 

26,190

13,960 

5,150 

3,440 

6,550 

18,700

5,410 

12,080 

10,680 

11,980

25,860

2,760 

3,020 

1,250

5,010

Mar.

4-10

4,650 

3,060

3,890

12,130 

15,260

4,490

7,890

30.550 

17,020 

1,590

14,310 

20,770 

9,240 

2,290 

128

891 

579

2,040 

762 

9,600

2,650 

781 

928 

1,710 

9,360

16,340 

2,340 

3,570 

5,590

6,470

835 

978 

391

1,370

Maximum 

24 

hours

8,830 

5,020

5,490

21,560 

22,910

11,620

26,320

33,220 

40,780 

17,320

41,300 

66,510 

15,650 

4,270 

4,120

1,900 

1,080

4,540 

1,370 

19,660

9,300 

3,750 

2,430 

4,790 

#10,120

5,180 

10,000 

9,140 

8,050

17,790

1,510 

1,660 

798

3,469

Retention 

(inches)

12 p.m. 

Mar. 3

8.94 

7.08

12.19

10.25 

10.10

7.49

7.08

7.35 

7.70 

6.28

18.07 

12.53 

17.69 

13.28 

10.51

11.35 

12.54

13.24 

10.86 

17.09

14.45

16.83 

11.84 

13.26 

8.63

7.60 

9.77 

16.74 

10.55

11.56

12.73 

13.07 

15.80

15.02

12 p.m. 

Mar. 10

8.71 

6.31

10.93

9.81 

9.59

7.23

6.83

6.46 

7.27 

6.14

16.06 

12.27 

13.75 

10.74 

10.49

9.41 

10.15

11.31 

8.53 

13.33

13.24 

15.87 

8.21 

10.08 

7.37

7.17 

9.56 

12.78 

9.30

8.55

10.28 

10.25 

13.55

13.47

c Excluding Bear Valley.

d Excluding Bear Valley and San Jacinto River,

e Area below Elsinore Lake.
362 FLOODS OF MARCH 1958 IN SOUTHERN CALIFORNIA

Table 26.- Rainfall, runoff, and retention for 

selected atreams in southern

No. 

on 

pis. 

11,12, 

13

81

85

85

86

87

89

97

101

105

108

111

113

115

141

143

144

150

151

155

159

161

162

163

164

165

Stream and point of measurement

San Gabriel River Basin Continued

Dalton Creek at flood-control reservoir

near Gtlendora

Little Dalton Creek near Gtlendora

Live Oak Creek at flood-control reservoir near La Verne

San Jose Creek near Whittier

Thompson Creek at flood-control reservoir near Claremont

Brea Creek at Fullerton

Los Angeles River Basin

Pacoima Creek at flood-control reservoir

near San Fernando

Tujunga Creek at floods-control reservoir

near Sunland

Haines Creek near Tujunga

Arroyo Seco near Pasadena

Santa Anita Creek at flood control reservoir near Sierra Madre

Little Santa Anita Creek at flood-control

reservoir near Sierra Madre

Eaton Creek at flood-control reservoir

near Pasadena

Santa Clara River Basin

Piru Creek near Piru

Sespe Creek near Fillmore

Santa Paula Creek near Santa Paula

Ventura River Basin

Mat 111 ja Creek at Mat ill ja

Ventura River near Ventura

Coyote Creek near Ventura

Santa Ynez River Baa in

Santa Ynez River at Juncal Reservoir near

Monteclto

Santa Ynez River below Gibraltar Dam, near

Santa Barbara

Santa Ynez River near Santa Ynez

Santa Ynez River near Lompoc

Santa Maria River Basin

Cuyama River near Santa Maria

Huasna River near Santa Maria

Drainage 

area 

(square 

miles)

4.49

3.3

2.30

85.2

3.91

26.4

27.8

81.4

1.2

16.4

10.8

2.39

9.48

432

254

39.8

55

 187

41.1

16.0

219

435

790

902

119

Mean areal 

rainfall 

Feb. 27 

to 

Mar. 3 

( inches )

17.85

19.87

17.41

10.74

17.41

11.22

18.90

18.10

19.38

21.86

25.76

22.74

22.39

12.35

14.96

15.89

15.44

13.32

12.78

14.69

12.62

12.12

10.08

5.31

4,16

Maximum daily mean.
RAINFALL, RUNOFF, AND RETENTION 363

the period February 27 to March 10, 1938, for 

C alif ornia C ontinued

Runoff

Inches >

Feb. 27 

to 

Mar. 3

5.93

6.11 

3.73

2.62 

3.95

1.66

5.98

7.21

3.52 

10.10 

11.06

6.94

5.90

2.18 

4.02 

4.95

5.66 

5.78 

4.65

4.67

2.76

2.61 

1.71

.24 

.58

Mar. 

4-10

2.08

1.94 

.69

.08 

.89

.01

2.60

1.36

1.02 

2.69 

3.52

2.97

1.80

.66 

2.48 

2.36

4.22 

2.00 

1.16

2.14

1.21

1.78 

1.23

.19

.89

Maximum 

24 

hours

3.83

#3.14 

2.50

#1.93 

2.75

#1.33

4.17

5.73

2.48 

6.83 

6.84

3.87

3.79

1.16 

2.30 

2.89

3.49 

3.90 

3.16

3.32

2.07

1.83 

1.22

.22 

.28

Acre -feet

Feb. 27 

to 

Mar. 3

1,420

1,010 

457

11,940 

845

2,340

8,820

31,290

225 

8,820 

6,380

888

2,970

50,250 

54,670 

10,510

16,620 

57,620 

10,200

' 3,980

32,250

60,550 

72,040

11,800 

3,700

Mar.

4-10

496

321

85

341 

186

734

3,850

5,820

65 

2,350 

2,020

377

916

15,140 

33,760 

5,010

12,380 

19,920 

2,550

1,820

14,130

41,360 

51,670

8,920 

5,640

Maximum 

24 

hours

917

#520 

307

#8,790 

573

#1,870

6,177

24,865

159 

5,970 

3,941

493

1,918

26,710 

31,220 

6,140

10,240 

38,900 

6,930

2,830

24,160

42,880 

- 51,190

10,600 

1,800

Retention 

( inches )

12 p.m. 

Mar. 3

11.92

13.76 

13.68

8.12 

13.46

9.56

12.92

10.89

15.86 

11.76 

14.70

15.80

16.49

10.17 

10.94 

10.94

9.78 

7.54 

8.13

10.02

9.86

9.51 

8.37

5.07 , 

3.58

12 p.m. 

Mar. 10

9.84

11.82 

12.99

8.04 

12.57

9.55

10.32

9.54

14.84 

9.07 

11.18

12.83

14.69

9.51 

8.46

8.58

5.56 

5.54 

6.97

7.88

8.65

7.73 

7.14

4.88 

2.69
364 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The basin in which the natural storage drains out most rapidly is 

that of Santa Ysabel Creek. During the period March 4 to 10 the runoff 

in this basin was 1.26 inches and during the longe^ period March 4 to 

September 30 it was 5.90 inches, an amount which with the transpiration 

losses during the same period, must have exhausted the retention of 12.19 

inches left by the March storm. In the San Vincente Creek Basin,the runoff was 0.77 inch for the period March 4-10 and 2.13 inches for the period 

March 4 to September 30, 1938; in this basin, also, it appears that the 

retention of 7.08 inches from the March storm was hardly enough t^o satisfy 

the demands of transpiration and the runoff during the period. Murrieta 

Creek Basin had the least runoff 0.14 inch March 4-10 and 0.50 inch March 

4 to September 30. As in the other stream.basins already discussed, it 

is doubtful if the retention of 6.28 inches on March 3 could have been 

more than equal to the losses by transpiration and the runoff during the 

period of March 4 to September 30. Pt seems very probable, therefore, 

that antecedent precipitation had an important but indeterminate effect 

on the runoff during this period.

Santa Ana, San Gabriel, and Los Angeles River Basins

The rainfall during the storm of March 1938 was heavier in the Santa 

Ana, San Gabriel, and Los Angeles River Basins than in any other parts of 

southern Califorotiia. The amount of rainfall for these basins, together 

with the runoff for two characteristic phases of the storm period, February 27 to March 3 and March 4 to 10, and the differences between rainfall 

and runoff are shown in table 26.

The average storm rainfall on the drainage areas listed ranged from 

7.74 inches on the valley floor to 28.58 inches at high altitudes in the 

mountains. In most of the area it was the heaviest rainfall experienced 

in many years.

The discharge for the maximum 24-hour period was apparently governed 

by the rates of rainfall, the rates of infiltration, and the amount of 

water already in groundwater storage. During the maximum 24-hour period, 

the records from the flood-control reservoirs in Los Angeles County 

showed an average runoff of 4.55 inches, which represents about 66 percent 

of the entire flow during the 5-day period February 27 to March 3. Of 

these reservoir stations, that of the West Fork of San Gabriel River recorded the greatest runoff for the maximum 24-hour period, a total of 8.26 

inches, which was 68 percent of the flood runoff to and including March 3.
RAINFALL, RUNOFF, AND RETENTION 365

The runoff from the drainage area above the Live Oak Creek Reservoir was 

the least for the group--2.50 inches during the maximum 24-hour period, or 

67 percent of the runoff for the part of the flood period ending March 3, 

a percentage almost identical with that of the West Fork of the San Gabriel River. The discharge for the maximum 24-hour period on Tujunga 

Creek accounted for 80 percent of the flood runoff for the same period 

and was the greatest concentration of inflow reported for any of the reservoirs. Little Santa Anita Creek showed the least concentration of 

runoff, that for the maximum 24-hour period being equal to 56 percent of 

that for the 5-day storm period February 27 to March 3. On the whole, 

most of the runoff records compiled from the other reservoirs were much 

more consistent, the maximum 24-hour runoff generally falling within 4 

percent of the average, Indicating uniformity of storm characteristics and 

other conditions in these particular areas.

In that part of the San Oabriel and San Bernardino Mountains drained 

by the Santa Ana River, the computed runoff for the maximum 24-hour period 

was 75 percent of the runoff for the 5-day storm period, a percentage considerably higher than that indicated by the -reservoir records. This 

greater concentration of runoff may have resulted from the heavier rainfall and the generally steeper slopes, especially in that part of the San 

Oabriel Mountains tributary to the Santa Ana River.

The three main streams in the Santa Ana River Basin draining the San 

Oabriel Mountains are San Antonio, Cucamonga, and Day Creeks. Of these 

streams, San Antonio Creek had the greatest runoff during the maximum 24- 

hour period as well as the greatest concentration. During the maximum 

24-hour period the runoff amounted to 86 percent of that for the 5-day 

period. Day Creek had a concentration during the maximum 24 hours of 71 

percent, and Cucamonga Creek 73 percent.

The drainage areas of Lytle, Cajon, and Lone Pine Creeke have many 

characteristics in common, including slope and altitude, and all three 

streams drain both the San Oabriel and San Bernardino Mountains. The runoff of Lytle Creek during the maximum 24-hour period was 74 percent of the 

runoff during the 5-day storm period February 27 to March 3; that of Cajon 

Creek was 67 percent; and Lone Pine Creek, 73 percent. These ratios are 

In fairly close agreement with the average of the Santa Ana River stations 

in the San Oabriel and San Bernardino Mountains.
366 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The southern slopes of the San Bernardino Mountains are drained by 

the Santa Ana River and by Mill, Plunge, City, Strawberry, Waterman Canyon, and Devil Canyon Creeks. The discharge of Santa Ana River and of 

Mill Creek for the maximum 24 hours indicated a runoff equal to 82 percent 

of the storm runoff for the period February 28 to March 3, which represents the greatest concentration of runoff in this group. Strawberry 

Creek showed the least concentration 69 percent. The average concentration of runoff for these streams is greater than that shown by the floodcontrol reservoir records in the basins of San Gabriel and Los Angeles 

Rivers.

The San Jacinto River Basin above San Jacinto possesses many characteristics similar to those of the other tributaries of Santa Ana River. 

However, owing to a lighter rainfall in this area, there was no exceptionally high runoff during the storm of March 1938. The maximum daily runoff 

was 1.36 inches, or 54 percent of that for the 5-day storm period. The 

peak discharge during the March storm was 14,300 second-feet on March 2, 

as compared with 14,000 second-feet on February 6, 1937. A peak discharge 

of 30,000 second-feet near San Jacinto was recorded in January 1916, and 

one of 45,000 second-feet on February 16, 1927, the latter caused, in 

part, by the failure of ft dike at Hemet Reservoir.

The longest record of runoff in the San Gabriel River Basin is that 

for the station on the main stem of the river near Azusa, which was established in 1894. The determination of the natural runoff at this station 

is now difficult .owing to the regulation at the two flood-control reservoirs and at Morris Dam. The maximum discharge of the San Gabriel River 

at the Azusa station might have been as high as 100,000 second-feet during the flood of March 1938 had there been no regulation. The maximum 

previously recorded was 40,000 second-feet on January 18, 1916.

All the streams in the Los Angeles River Basin listed in table 26 

drain the San Gabriel Mountains. The discharge for the maximum 24-hour 

period for stations on these streams shows a greater variation in degree 

of concentration than in any of the other areas in southern California. 

The two extremes for this basin, as already mentioned, are Tujunga and 

Little Santa Anita Creeks.

The storm runoff March 4 to 10 represents a draining out of ground 

water, which in its characteristics of amount and rate, of movement would 

seem to .be closely related to the characteristics of the geologic formations with respect to their capacity for storing water. The draining out
RAIHPALL, RUHOFF, AND RETENTION 367

was also dependent on the retention from the March storm and from antecedent precipitation, which may have included some ground-water storage 

remaining from the abnormally high rainfall during the season of 1936-37. 

During the period March 4 to 10, the average runoff, as based on the 

flood-control reservoir records, was 2.16 inches. Santa Anita Creek had 

the largest runoff 3.51 inches and Live Oak Creek the least 0.69 inch.

For the Santa Ana River near Mentone the runoff during the draining 

out period, March 4 to 10, was 2.01 inches. For the adjacent basin of 

Mill Creek during the same period the runoff was 3.94 inches, or nearly 

twice as great. For the period March 4 to September 30, 1938, the runoff 

for the Santa Ana River near Mentone was 13.27 inches, as compared with 

22.61 inches for Mill Creek. During the same period, the runoff from 

Lone Fine Creek was only 3.1 inches. As shown by table 26, the retention 

in these three basins was nearly the same at midnight March 3.

Strawberry Creek, which is typical of the short mountain tributaries 

in the San Bernardino Mountains, had a runoff of 1.94 inches for the 7- 

day period March 4 to 10 and for the longer period March 4 to September 

30, 13.7 inches.

In that part of the San Gabriel River Badin draining the San Gabriel 

Mountains, the West Fork of San Gabriel River showed the most rapid release of ground water, with 3.01 inches of runoff between March 4 and 10. 

San Dimas Creek had the least runoff with 1.55 inches for the same period.

Because of storage losses and diversion during the summer, it was 

not practicable to compare the runoff from the basins of the controlled 

streams for the longer period March 4 to September 30. Fish Creek, in 

the San Gabriel River Basin, which is not regulated, had a runoff during 

this period of 14.1 inches, which is comparable to the runoff for Strawberry Creek, in the Santa Ana River Basin.

In the Los Angeles River Basin-during the period March 4 to 10 Santa 

Anita Creek had the largest runoff, 3.51 inches, and Haines Creek had the 

least, 1.02 inches. The average runoff for the entire group in this basin 

as shown in table 26 was 2.28 inches. During the period March 4 to September 30, 1938, the runoff of Arroyo Seco was 11.8 inches, and that of 

Santa Anita Creek was 14.3 inches.
368 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA 

Santa Clara and Ventura River Basins

There was no regulation or diversion on any of the streams in the 

Santa Clara and Ventura River Basina for the period February 27 to March 

10. The average runoff at the stations on these streams was 4.54 inches 

for the period February 27 to March 3, which ia somewhat leaa than the 

average for the streams in the Santa Ana, San Gabriel, and Los Angeles 

River Baa ins, probably on account of the lighter rainfall.

In the Santa Clara River Baain, the ratio of the runoff for the 

maximum 24-hour period to the runoff for the period February 27 to March 

3 was 53 percent on Piru Creek, 57 percent on Sespe Creek, and 58 percent 

on Santa Paula Creek.

In the Ventura River Baa in, the ratio of runoff for the maximum 24 

hours to that for the period February 27 to March 3 was 62 percent on 

Matilija Creek, 67 percent on Ventura River, and 68 percent on Coyote 

Creek.

During the draining-out period March 4 to 10, the average runoff from 

theae aix streams in the Santa Clara and Ventura River Baaina waa 2.15 

inches, which approximates closely the average of the recorda from the 

flood-control reservoirs in Loa Angeles County. Piru Creek had the leaat 

runoff, 0.66 inch during the period March 4 to 10 and 2.5 inches during 

the period March 4 to September 30. Sespe Creek, an adjacent stream, had 

a runoff of 2.48 inches during the period March 4 to 10 and 7.8 inches 

March 4 to September 30.

Santa Ynez and Santa Maria River Basins

The Saata Ynez and Santa Maria River Basins are situated on the extreme northern edge of the area affected by the storm of March 1938. In 

the main, the characteristics of the rainfall, runoff, and retention in 

these two basins were very similar to those in the Santa Clara and Ventura River Basins. The heavy rainfall in February had increased the 

ground storage in about the same proportion as in some of the basins to 

the south.

The average runoff from streams in these basins (see table 26) for 

the maximum 24-hour period waa 1.49 inches, which is 71 percent of the 

total1 average runoff for the period February 27 to March 3. Santa Ynez 

River at Juncal Reservoir had the highest maximum 24-hour runoff In these 

basins, 3.32 inches. This rate is only slightly less than that for San
ARTIFICIAL STORAGE 369

Dlmas, Eaton, Dalton, and Little Santa Anita Creeks. Although those latter stations had a rainfall for the maximum 24-hour period of 9.5 to 11.3 

Inches, It Is doubtful If the rainfall on the Santa Ynez River Basin above 

Juncal Reservoir exceeded 8.0 Inches for the same period. The other stations on the Santa Ynez River, and those on the Santa Maria River show 

considerably less runoff, owing principally to a much lighter rainfall.

The runoff of Santa Ynez River at Juncal Reservoir during the period 

March 4 to 10 was 2.14 Inches and for the period March 4 to September 30, 

11.22 Inches.

The-ralnfall In the Santa Maria River Basin was comparatively light 

and the flood was not especially severe.

ARTIFICIAL STORAGE

The detention and retardation of flood flows by storage reduces the 

peak stages of streams at critical times and, to the limit of the available storage capacity, Is an effective method of reducing flood damage. 

In the mountainous headwater areas of the Santa Ana, San Gabriel, and Los 

Angeles River Basins are a number of reservoirs used either for water 

supply or flood control purposes.

The influence of reservoirs on the flood of March 1938 Is shown by 

the data presented In table 27, many of which are taken from the report 

by Burke.36 fne table gives the total storage capacity and the storage 

available at the beginning of the maximum 24-hour period of runoff, the 

runoff for the 3 days prior to the maximum 24-hour period, the runoff for 

the maximum 24-hour period, the peak inflow, the peak outflow, the Interval between time of peak inflow and peak outflow, and other pertinent 

data.

The difficulty of operating the reservoirs for material reduction of 

flood peaks such as occurred on March 2, 1938, can be seen by comparing 

the capacity with the volume of Inflow. The total capacity, at spillway 

level, of the reservoirs operated primarily for flood control in San Gabriel and Loa Angeles River Basins was 105,000 acre-feet; the runoff 

during the 3 days prior to the maximum 24-hour period was about 41,400 

acre-feet, and the runoff during the maximum 24-hour period was about 

146,000 acre-feet.

36 Burke, M. F., Flood of Mar. 2, 1938, Los Angeles County Flood 

Control District, May 20, 1938. (Mimeographed)
370 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

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ARTIFICIAL STORAGE 371

The runoff Incident to the first phase of the storm utilized about 

half of the total available capacity, and In consequence only about a 

third of the runoff during the 24 hours of maximum discharge on March 2 

could be retained. Although on some of the streams the effect on the 

maximum peak discharge may have been relatively small, the general effect

was to reduce the total amount of water that accumulated In overflow

i 

areas below the reservoirs, and all the reservoirs acted as debris basins,

effectively trapping large accumulations of silt that might otherwise 

have been deposited outside the mountain areas.

At several flood-control dams the silt and debris accumulated to an 

altitude above that of some of the outlets, which Interfered with the 

regulating of the gates to achieve maximum flood-control efficiency.

Several reservoirs on smaller streams in the Santa Ana River Basin 

contributed substantially to the lowering of the flood peaks on those 

streams but had little effect on the peak In the Santa Ana River. Elslnore Lake, fed by the San Jaclnto River, did not overflow. Overflow from 

this lake would pass down Temescal Creek to the Santa Ana River.

The San Gabriel River was effectively controlled by storage in San 

Gabriel River Flood-control Reservoir Ho. 1, the peak discharge being reduced from 90,000 to 56,700 second-feet. No water was released from 

Puddingstone Reservoir, storage in which reduced the peak discharge on 

Walnut Creek. This reservoir also stored water diverted.from San Dimas 

Creek, thereby reducing the flow in the lower reaches of that stream. 

Other smaller flood-control reservoirs in the basin had little effect on 

the flood in the San Gabriel River.

In the Los Angeles River Basin there are a number of reservoirs, 

whose combined capacity, at spillway level, is about 54,000 acre-feet, of 

which about 18,000 acre-feet is operated solely for flood control. The 

effect of these reservoirs on the flood peak in the Los Angeles River was 

not material.

Although reservoirs on the smaller streams did not appreciably reduce the peak discharge of the larger rivers, they did retain larga 

amounts of silt and debris and thus materially reduced the damage to the 

highly developed areas adjoining the streams at lower altitudes.
372 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

DEBRIS 

Interception of debris by reservoirs and debris basins

As already noted, the streams that have their sources on the southern slopes of the San Gabriel and San Bernardino Mountains flow into the

J;->

San Fernando, San Gabriel, Chino, and upper Santa Ana Valleys. As disclosed by well drilling in the central part of San Gabriel Valley, all 

these valleys are, in the main, underlain by alluvial deposits 1,000 to 

2,000 feet deep. At the heads of the valleys are a series of debris 

cones, some of enormous size, all bearing witness to large debris movements in the past.

In earlier years the debris-laden streams meandered during flood periods more or less at will over the debris cones and valley floor, as 

explained in the subsequent chapter on history of floods. As the valley 

floor was populated, it became more and more necessary to confine the 

meandering streams to fixed channels. Until recent years the accommodation of the accumulating debris was not a serious problem, as the debris 

cones still afforded areas tor further deposition.

As settlement has increased, however, the tillable lands along the 

cones have be-en utilized for orchards, homes, and in some places for considerable urban development. Because of this use of the lands the control 

of the movement of debris on the cones has become an important economic 

problem. Streams that formerly meandered and dropped much of their bed 

load and silt content over the cones in a normal, natural manner now have 

to be confined within fixed channels in order to protect man's improvements. The practice of confining these streams to direct routea across 

the debris cones has necessarily resulted in the transportation to the 

valleys below of much of the debris that formerly was deposited on the 

cones. (See pi. 9.) In an attempt to alleviate this situation, at least 

in part, debris or catchment basins have been excavated In the stream 

channels near the apexes of some of the conea. The capacity of these basins ranges from about 12.5 acre-feet to 98 acre-feet.

One of the debria basins, located on the Dunsmuir Creek debris cone, 

is illustrated on plate 19, which shows the inlet structure and the outlet structure with the overflow weir. Between these two structures is 

the excavated basin in the cone, which has debris storage capacity of 

about 80 acre-feet. The steepness of the cone is clearly shown in plate 

19,A, and a part of the urban development in the valley below can be seen 

in plate 19,B.
DSBRIS 373

To maintain the effectiveness of these basins it is necessary to remove the aocumulated debris after each heavy storm and to transport it 

elsewhere With the continued extension of improvements in the area, the 

disposal of the material trapped in the debris basins has become a serious 

problem. Plate 20 shows the Dunsmuir Greek debris basin immediately following the March flood and before its re-excavation had started.

The flood-control reservoirs that have been constructed for the storage and temporary retention of flood runoff also act as debris basins. 

Table 28 gives pertinent data, furnished by the Los Angeles County Flood 

Control District and the United States Soil Conservation Service, relating 

to deposits of debris in the debris basins and flood-control reservoirs. 

For the flood-control reservoirs, the column "Debris deposited" indicates 

the total volume of debris per square mile removed from each drainage 

area; but for the debris basins, because their capacity for catchment may 

have been exceeded, the volume shown in this column may not be the total 

volume of debris so removed. The volume of debris listed in the.table includes not only the material actually trapped in the basin or reservoir, 

but also the deposits in the channel Just upstream from the debris basin. 

The runoff in acre-feet per square mile for the maximum 24-hour period is 

given if available.

The loss in capacity of the reservoirs as shown in table 29 is for 

the period between the last previous survey and the flood of March 1938. 

It is believed that practically all of the movement of debris causing this 

loss in capacity occurred during the storm period of March 1938 and that 

most of the debris was deposited within the maximum 24-hour period of 

fldbd runoff.

The data in table 28, ehown graphically in figure 39, indicate a relation between the average slope of a drainage basin and the accumulation 

of debris. The slope of these drainage basins Is extraordinarily steep, 

the average Increase In altitude within a horizontal distance of 100 feet 

ranging from 36 to 76 feet. Detailed field studies made in connection 

with the flood on New Year's Day, 1934, in the La CaHada area 37 indicate 

that the debris moved out of the canyon area during severe storms represents the gradual accumulation In channels during a period of years of 

low runoff rather than the direct movement from the area as a whole during a single flood period.

37 Troxell, Harold C., and Peterson, John Q. Flood in La Canada. 

Valley, Calif., January 1, 1934s U. S. Qeol. Survey Water-Supply Paper 

796-C, p. 93, 1937.
374 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Table 28.- Deposition of debris in reservoirs and debris basins of the 

Los Angeles County Flood Control District

Reservoir or basin

Flood-control reservoirs

Big Dalton

Devils Gate (Arroyo Seco)

Eaton Creek

Live Oak Creek

Paooima Creek

San Dimas Creek

San Gabriel River No. 1

San Gabriel River No. 2 (West Fork)

Santa Anita Creek

Sierra Hadre (Little Santa Anita

Creek)

Sawpit Creek

Thompson Creek

Tujunga Creek

Debris basins

Brand

Dunsmuir

Eagle -Qoss

Fair Oaks

Fern

Haines

Hall-Beckley

Hay

Las Flores

Lincoln

Nichols

P tokens

Shields

Snover

West Ravine

Drainage 

area 

(sq.mi. )

4.5

30.6

9.5

2.3

27.8

16.5

202

40.4

10.8

2.4

3.3

3.9

81.4

1.03

.84

.61

.21

.30

1.53

.84

.20

.42

.50

.94

1.84

.27

.23

.25

Average 

slope of 

drainage 

area 

(percent)

40

-

58

36

41

42

49

47

47

50

50

36

44

62

67

65

61

62

71

74

56

65

51

54

69

76

49

69

Debris 

deposited 

(acrefeet per 

sq.mi. )

19.6

41.5

 50.9

6.5

21.4

17.3

38.3

39.2

40.1

16.7

24.5

7.7

19.7

8.1

43.4

41.5

35.3

42.8

21.1

68.8

39.0

55.2

21.1

11.8

50.8

74.4

45.2

73.1

Maximum 

24 -hour 

inflow 

(acrefeet per 

sq.mi. )

204

, 242

203

134

225

212

368

442

360

207

242

147

306

 .

_

-

_

-

_

_

^

-

 »

-

Runoff that might be sufficient to transport debris on slopes as 

steep as these canyon walls may lack the force to move it along slopes as 

flat as those found in the canyon floors. Thus material washed off the 

mountainsides may accumulate in stream beds until such time as the area is 

visited by a major flood, when most of the accumulation may be moved out 

on the debris cone or valley floor. This is, in a measure, indicated by 

the observations at the reservoirs. For example, San Dimas Creek floodcontrol reservoir, built in September 1922, has lost to date 22.8 percent 

of its capacity, of which it is estimated 18.1 percent was lost during 

the flood of March 1938. For the 15-year period prior to this flood the 

capacity of the reservoir had been reduced by only about 4.7 percent, although during that time there were at least three severe storms. It seems
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 19

A. EXCAVATED BASIN AND INFLOW STRUCTURE.

B. OUTFLOW STRUCTURE.

DUNSMUIR DEBRIS BASIN AFTER EXCAVATION OF DEBRIS.

Courtesy of Corps of Engineers, U. S. Army.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 20

A. VIEW UPSTREAM SHOVING DEBRIS DEPOSITS UP TO ALTITUDE OF INFLOW

STRUCTURES.

B. VIEW DOWNSTREAM.

DUNSMUIR DEBRIS BASIN FULL OF DEBRIS, MARCH 1], 1938.

Courtesy of Corps of Engineers, U. S. Army.
DEBRIS 375

Table 29.- Loss in capacity of reservoirs of the Los Angeles County Flood Control

District

Heservoir or basin

Big Dalton

Devils Gate (Arroyo

Seoo)

Eaton Creek

Live Oak Creek

Paeoina Creek

San Diraas Creek

San Gabriel Hiver

Do. 1

San Gabriel River

Ho. 2 (Vest Fork)

Santa Anita Creek

Sawpit Creek

Sierra Madre

(Little Santa

Anita Creek)

Thompson Creek

Tujunga Creek

Total

Altitude

of

spillway*

1,706

1,064

888

1,497

1,950

1,462

1,453

2,385

1,316

1,360

1,172

1,640

2,290

Date 

storage

began

Aug. 1929

June 1920

Feb. 1937

Bbv. 1922

Feb. 1929

Sept .1922

Bbv. 1937

Apr. 1935

Mar. 1927

June 1927

Feb. 1928

Mar. 1928

July 1931

Original 

capacity

acrefeet

1,060

4,563

940

250

6,060

1,496

53,334

12,320

1,043

431

49.5

812

6,240

88,606.5

Date of 

last 

survey

prior to 

Mar. 1938

Oct. 1937

Dec. 1936

Kov.1937

Mar. 1936

Jan.1936

Oot.1937

Jan.1938

Oct. 1935

Feb.1936

Oct. 1935

Mar.1932

Apr.1932

Feb. 1929

Capacity below 

spillway level

Prior to 

Mar. 1938

1,040

3,825

940

242

5,592

1,399

53,334

12,298

1,010

389

47.4

812

6,240

87,168.4

Apr.1938

t974 .

2,967

1

698

229

5,004

tl,188

47,191

10,787

683

320

8.5

786

4,734

75,579.5

Loss in 

capacity

Acrefeet

66

848

242

13

588

211

6,143

1,511

327

69

38.9

26

1,506

11,588.9

Percent*

6.2

18.6

25.7

5.2

9.7

14.1

11.5

12.3

31.4

16.0

78.6

3.2

24.1

13.1

gote«- Data furnished by U. S. Soil Conservation Service.

* Altitude in feet above mean sea level. 

** Percentage of original capacity lost since last survey.

t October 1938.

probable that the debris moved into the reservoir by the storm of March 

1938 represents a part of the debris removed from the canyon walls and 

accumulated in the stream bed during a relatively long preceding period.

Santa Anita Creek flood-control reservoir has had a reduction of 

34.5 percent in capacity since its construction in March 1927, of which 

about 31.4 percent occurred during the storm of March 1938. Thus during 

the 11 years preceding March 1938 the redaction was only 3.1 percent. 

A large part of the mountain drainage area in the vicinity of La 

Canada was burned over in the fall of 1933, and the fire was followed by 

the severe storm that caused the New Year's flood of 1934. Large amounts 

of debris that had accumulated during the preceding years of below-normal 

precipitation were transported out of the canyons during that flood. The 

basins in which flood-control reservoirs had been constructed were not 

within the area in which the 1934 flood was heaviest, and the movement of 

debris down the stream channels was not nearly so great as in the La 

Canada area. Following the New Year's flood of 1934, many debris basins 

were constructed, most of them in the La Canada area. This may explain 

the indication of figure 39 that for the storm of March 1938, in drainage 

basins of equal slope, the debris movement into the reservoirs, in acrefeet per square mile of drainage area, was considerably greater than the 

movement into the debris basins.

454720 O - 42 - 25
100

90

80

30

15 20 25 

Debris, in acre-feet per sq

EXPLANATION

o Flood control resesvoirs

1.

2.

3.

4.

5.

6.

Dalton Creek

Eaton Creek

Live Oak Creek

Pacoima Creek

San Dimas Creek

San Gabriel River No. 1

7.

8.

9.

10.

11.

12.

San Gabriel River No

Santa Anita Creek

Sierra Madre (Little

Sawpit Creek

Thompson Creek

Tujunga Creek

. 2 (West Fork)

Santa Anita Creek)

13

14

15

16

17

18

Figure 39.- Relation between average slope of drainage basin and deposition of de

County Flood Control Di
DEBRIS 377 

Movement of debris in stream channels on the valley floor

The movement of debris in stream channels is not confined to the mountain areas but extends downstream to the flatter slopes, where the debris 

accumulates in the channels on the valley floor until such time as the 

area is visited by a major storm. Figure 40 shows the change in altitude 

of the point of zero flow for the channel of the Santa Ana River near 

Prado during the period 1919-38. This change Is an Indicator of streambed scour and fill. The maximum discharge and the date of its occurrence 

are given for each flood that caused noticeable scour In the channel. The 

storm of February 1927 lowered the point of zero flow 3.5 feet and appears to have caused the greatest stream-bed scour during the period of 

record. Except for the scouring and filling, the channel characteristics 

at the gaging station have remained fairly constant throughout the period 

of record.

It will be noted that following each storm period there Is a noticeable deposition In the stream channel, amounting In some years to almost 

0.5 foot. During the comparatively dry period from July 1927 to December 

1931 the channel appears to have been built up about 1.3 feet.

About three months before the storm of March 1938, In connection with 

a study of certain hydraulic features of the Prado flood-control dam, the 

Corps of Engineers, United States Army, surveyed a series of 22 cross sections in the channel of the Santa Ana River over a stretch of 4^- miles 

below the site of the proposed dam. Immediately following the storm the 

sites of these sections were relocated and new cross sections were determined. The changes In the sections with respect to scour or fill are 

shown In table 30.

During February 1937 the Orange County Flood Control District surveyed a series of cross sections under each of the highway bridges across 

the Santa Ana River in Orange County. Immediately after the flood of 

March 1938 these sections were redetermlned. The Indicated scour at each 

section Is likewise shown In table 30.

Only 2 of the 30 sections Included In table 30 showed a fill In the 

channel during the flood period. At the other sections the scour was as 

 nuch as 6.79 feet at the State Highway bridge at the mouth of the river. 

The average depth of scour for the entire group was about 1.47 feet over 

the entire width of the channel.
378 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA
DEBRIS 379

Table 30.- Scour and fill in channel of the Santa Ana River due to flood

of March 1938

Distance 

above coast 

highway 

(miles)

31.59

31.50

31.46

31.43

31.41

31.37

31.34

31.30

31.21

30.99

30.80

30.61

30.41

30.19

29.91

29.68

29.38

29.07

28.84 (a)

28.40

27.93

27.36

20.43 (b)

17.51 (c)

17.06 (d)

15.45 (e)

13.70 (f)

8.83 (g)

5.28 (h)

0 (i)

Width 

(feet)

2,000

1,850

1,900

2,000

1,400

1,450

1,250

1,350

1,300

1,300

1,600

2,000

1,750

1,250

1,800

1,750

3,250

1,700

750

2,000

1,500

1,800

1,000

_

942

1,000

1,277

346

291

520

Change in cross section

Scour 

(square feet)

_

100

1,220

1,830

1,430

1,820

1,630

1,250

590

2,570

500

780

2,560

4,000

3,860

4;350

2,110

2,250

1,330

-

2,010

8,500

1,150

274

1,726

1,824

594

166

611

3,531

Fill 

(square feet)

1,190

-

-

-

-

_

-

-

-

-

_

-

-

-

-

_

-

_

-

7,340

_

_

-

_

-

_

-

_

-

-

Change in mean depth

Scour 

(feet)

_

0.05

.64

.92

1.02

1.26

1.30

.93

.45

1.98

.31

.39

1.46

3.20

2.14

2.49

.65

1.32

1.77

-

1.34

4.72

1.15

1.83

1.82

.47

.48

2.10

6.79

Fill 

(feet)

0.60

-

-

-

-

_

-

-

~

-

_

-

-

 

-

_

-

_

-

2.67

_

_

-

_

-

_

-

_

_

-

a River-measurement station near Prado.

b Yorba Bridge.

c Jefferson Street Bridge.

d A.T.& S.F.Ry.Bridge.

e Anaheim-Olive Bridge.

f Southern Pacific Co. Bridge.

g Fifth Street Bridge.

h Talbert Avenue Bridge.

i Coast Highway Bridge.

There is a wide variation in the degree to which the sand deposits 

in the channel will scour during periods of flood runoff. Many bridge 

piers were undermined and many buried pipe lines across the stream channels were wrecked during the flood of March 1938.

Not all sections of the stream channels across the valley floor were 

subject to appreciable scour. In order to obtain additional data on 

scour, the Corps of Engineers, United States Army, on October 1, 1936, 

placed three series of boulders in the deep sandy channel of the Los Angeles River between Firestone Boulevard and Stewart and Grey Road.
380 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The first series consisted of five boulders weighing about 400 pounds 

each,-which were placed in line across the channel and buried a short distance' below the surface. Two of these boulders have shown no change in 

position except for a slight settlement; one moved downstream about 40 

feet during the relatively moderate storm of February 1937, but there was 

no movement in March 1938; another disappeared in February 1937; and only 

one appears to have moved during the flood of March, 1938.

Two hundred feet farther downstream was the second series, a row of 

six rocks each weighing 200 pounds and similarly placed. One of these 

was lost and two moved between 300 and 400 feet in February 1937; three 

disappeared and two showed no change in location during the flood of 

March 1938.

The third series of six rocks, each weighing 100 pounds, was placed 

200 feet downstream from the second series. All the boulders in this 

series disappeared during the storm of February 1937.

The results of this experiment seem to indicate that the storm of 

February 1937 had a greater scouring effect at this particular location 

than the considerably more severe storm of March 1938.

Much debris set in motion by the runoff from the storm of March 1938 

was deposited in the ocean at the mouths of the streams. The report by 

the Corps of Engineers ^8 indicates that at the mouth of the Los Angeles 

River a deposit of 8,120,000 cubic yards of debris formed above an altitude of 30 feet below sea level and within a strip 3,000 feet wide, 

bounded by the breakwater on the west and extending approximately 1 mile 

seaward. If the estimated quantity of fill beyond the limit of surveys 

is included, the total deposit was approximately 11,000,000 cubic yards. 

This represents the volume of debris deposited during a period of more 

than 10 years, as the last previous survey was made in 1927, by the city 

of Long Beach. During that period tidal currents undoubtedly had an effect on the deposition of debris. From a study of aerial photographs and 

a few soundings made between 1927 and 1938, it is estimated that 60 percent of the total, or 6,600,000 cubic yards of debris, was deposited by 

the flood of March 1938 in the immediate area. Further uncertainty as to 

the total volume carried by the river is caused by the possibility that 

some part of the debris may have been deposited outside this immediate 

area.

38 Corps of Engineers, U. S. Army, Report on engineering aspects s 

flood of March 1938, p. 37, 1938.
FLOOD DAMAGE 381

Similar data collected at the mouth of the San Gabriel River show a 

deposit of 273,000 cubic yards of debris above an altitude of 15 feet below sea level within a strip 1,600 feet wide extending directly seaward 

for 2,200 feet from the mouth of the river. The volume at the mouth of 

the San Gabriel River has undoubtedly been more accurately determined than 

that at the mouth of the Los Angeles River. It is based upon a survey 

made in September 1937. The absence of a breakwater here reduced the 

probability of excessive tidal effects, although tidal deposits and scour 

remain undetermined factors. As before, no estimate can be made of the 

volume of debris deposited outside the area surveyed.

FLOOD DAMAGE

Southern California sustained damages amounting to $78,602,000 from 

the storm of February 27 to March 4, 1938, according to the report compiled by the Corps of Engineers, United States Army, Los Angeles district; 

of this total, $27,413,000 has been estimated as indirect damage and 

$51,189,000 as direct damage. A large number of homes and business houses 

were either completely destroyed or badly damaged. Railroads 3 ^ and highways suffered losses estimated at many millions of dollars, owing to, 

destruction of bridges and roadbeds. Other utilities, such as the telegraph, telephone, gas, and water systems, were severely crippled. For a 

time some localities were cut off from all lines of communication and 

others were served only by airplane or radio.

The inundated area in Los Angeles County included about 108,000 

acres; in the Santa Ana River Basin in San Bernardino, Riverside, and 

Orange Counties, 182,300 acres; and in Ventura and Santa Clara River Basins, 6,200 acres. Plates 21-26, from photographs made March 3 show flood 

damage along the Santa Ana River.

Maps of southern California showing areas damaged by the flood of 

March 1938 have been prepared by the Corps of Engineers, United States 

Army; by the United States Department of Agriculture; and by the Los Angeles County Flood Control District (Los Angeles County only).

39 Kirkbride, W. H., A railroad fights floods! Civil Engineering, 

vol. 9, No. 12, pp. 711-714, December 1939.
382 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Loss of life

The total number of deaths caused by flood in southern California in 

1938 was reported as 87, of which 77 occurred in the Los Angeles and Santa 

Ana River Basins. Three months after the flood, 9 other persons were 

still reported as missing. The number of lives lost in each river basin 

is given in table 31.

Table 31.- Loss of life in southern California due to storm of 

February 27 to March 3, 1938

Drainage basin Llost

San Juan and Aliso Creek and other small basins in

Orange County .................... 2

Santa Ana River, including Coyote Creek ........ 34

San Gabriel River, excluding Coyote Creek ....... 1

Los Angeles River, excluding Rio Hondo ........ 43

Rio Hondo ....................... 2

Ballona and Topanga Creek and other coastal areas in _

Los Angeles County ................'. 3

Ventura River ..................... 1

Mojave River ..................... 1

87 

Flood-damage survey

Immediately after the storm the Corps of Engineers, United States 

Army began a thorough field investigation to determine the extent of the 

damage. Every property owner or renter in the affected areas that could 

be located was interviewed, and an itemized estimate of flood damage was 

made. Reports on the damage were obtained also from State, county, and 

city officials, from public and private utility agencies, and from private corporations.

In making this flood-damage survey the Corps of Engineers endeavored 

to determine, with reasonable accuracy, the indirect damage as well as the 

direct physical damage caused by the storm. According to the report, 40 

direct and indirect damage are defined as follows:

a. Direct damage Physical damage to property, measured by the cost 

of repair or replacement in kind, including cost of clean-up.

40 Wyman, Theodore, Jr., Report on flood damage in Los Angelea Engineers District from storm of February 27 March 3, 1938.
FLOOD DAMAGE 383 

b. Indirect damage Indirect losses resulting from the direct flood

(1) Loss of wages by employed persons.

(2) Loss of income from interruption of or delay in business, other than (4) or (5), below.

(3) Depreciation of property values in areas damaged.

(4") Loss of business by transportation companies due to 

damaged bridges and roadways.

(5) Loss to utilities of income of nonrecoverable types,

owing to interruption of services.

As it was not practicable to obtain a complete evaluation of the indirect damage in all areas, ratios of indirect to direct damage were 

determined from the fairly complete data available for the Los Angeles and 

San Gabriel River Basins, including San Antonio Creek, and applied to 

other areas for which only data on direct damage were available.

Flood damages, segregated in table 32 for various types of property, 

are based on compilations made by the Los Angeles District, Corps of Engineers, United States Army. Table 32 does not in the main, except for 

public utilities, include any of the losses that occurred in the mountain 

areas, most of which are within the boundaries of the Angeles, Padre, San 

Bernardino, and Cleveland National Forests. The losses due to the flood, 

in certain of these areas, though large, have not been completely determined. Among the items for which figures are available are $89,500 for 

Government-owned recreational facilities and 18 miles of Government-owned 

telephone lines valued at about $12,550, both within the Angeles National 

Forest. The flood damage in San Antonio Canyon, also in the Angeles National Forest, as determined by a survey conducted by the Corps of 

Engineers, amounted to $328,700, the largest item of which was the destruction of 219 privately-owned cabins on Government leases. The 

supervisor of the Angeles National Forest reported the loss, in all, of 

520 privately-owned cabins on Government leases. In most of the mountain 

canyons, however, the losses were considerably less than in San Antonio 

Canyon.
384 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

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FLOODS OP MARCH 1958 IN SOUTHERN CALIFORNIA 385

HISTORY OF FLOODS IN SOUTHERN CALIFORNIA 

-

Since January 7, 1770, when Father Juan Crespl first observed the

evidence of a great flood along the -Los Angeles River, the flood runotff 

from the San Gabriel and San Bernardlno Mountains and other parts of the 

Coast Ranges has periodically submerged, damaged, and washed away crops, 

homes, missions, bridges, highways, railroads, and other structures located by man for his convenience In, on, or over flood channels and flood 

plains that had been established by Nature for the passage of flood witers 

from the mountains to the sea. Only through discriminating consideration 

of these past floods can plans be formulated for protection from and Control of future floods, which will Inevitably occur. That damaging floods 

occurred In the past Is unquestionable; little Is known, however, of Iftie'lr 

relative magnitude. All were sufficiently severe to cause damage and 

temporary Inconvenience, and some caused loss of life. Residents of 

southern California should realize that, in spite of the application <of 

our most advanced technical and scientific knowledge of flood-control 

structures and practices, those who continue to occupy natural flood c|hannels, flood plains, and debris cones are defying inexorable laws of natture.

Records of floods in southern California are found in a wide variety 

of publications and in mission records, special reports, transcripts of 

court hearings, and statements of old-time residents of the country. The 

earliest references to floods are found in the diaries of the Spanish 

Mission Fathers. These early records indicate that there were floods in 

1770-71, 1771-72, 1775-76, and 1779-80.

Testimony in the case of Danerl v. The Southern California Railwa|y 

Co., in the Superior Court of Los Angeles County in 1897, and statements

obtained in 1915 from a large number of old residents and compiled by

41 Reagan were to the effect that there were floods on the Los Angeles

and San Gabriel Rivers in 1811, 1815, 1822, 1825, 1832, 1842, 1851-52, 

1859-60, 1862, 1867, 1884, 1886, 1889, 1891, and 1914.

Transcripts of public hearings concerning flood control held during 

1938 by the United States district engineer, War Department, recorded 

floods on the Ventura River in 1832, 1862, 1867, 1875, 1884, 1905, 1907, 

1911, 1914, 1926, 1927, 1934, and 1937, and on the Santa Ana River in 

1862, 1867, 1884, 1886,' 1889, 1890, 1906, 1908, 1909, 1914, 1916, 1918, 

1921, and 1926.

41 Reagan, J. W., Flood history of Los Angeles County, compiled 

from all available sources, 1914-15 (unpublished report).
386 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

Official weather observations in southern California were begun at 

San Diego in 1851, at Santa Barbara in 1867, and at Los Angeles in 1878.' 

Except for the floods recorded in their diaries by the Mission Fathers 

and a few isolated recorded statements by others, floods prior to 1851 

mentioned in the various reports are described by the various witnesses 

from their personal recollections or from what others had told them about 

earlier floods. It is quite possible that th'ere may have been other 

floods that were not recalled and also that the relative magnitude of the 

floods as given may be open to question.

The first known estimates of flood discharge actually made at the 

time of a flood were two separate and independent estimates made on the 

Los Angeles River for the flood of 1889, one by William Mulholland and 

the other by H. Hawgood. ^

Actual current-meter measurements of major peak discharges have never 

been made, but since about 1894, continuous stream-flow records have been 

collected for the major streams in southern California, and peak discharges have been computed or estimated by various methods. These records 

are available in the annual reports on surface-water supply and special 

reports published by the Geological Survey.

1770

Father Juan Crespi 43 gives us the first record of a flood in California. The following is quoted from his diary:

Jan. 17, 1770, * * * we saw the Poiciuncula [Los Angeles] River. We 

crossed the plain in a southeasterly direction, arrived at the river, and 

forded it, observing on its sand, rubbish, fallen trees, and pools on 

either side, for a few days previously there had been a great flood which 

had caused it to leave its bed.

The San Gabriel Mission was built about a mile from the banks of the 

San Gabriel River channel and about 3 miles directly south of El Monte. 

The fathers planted and cultivated the low bottom lands around the mission, but the crops of the first year were overflowed and destroyed in 

1772. In 177.6, owing to the recurrence of heavy flood flows, the mission 

was moved to its present location in San Gabriel, some 6 miles back from| 

the river.

42 Reports of the Board of Flood Control Engineers to the Board of 

Supervisors, Los Angeles County, Calif., p. 144, 1915.

43 Crespi, Father Juan, in Bolton, H. E., New California, vol. 2, 

p. 256, 1926.
HISTORY OF FLOODS IN SOUTHERN CALIFORNIA 387 

1780

The flood of 1780 is reported in the following note, taken from the 

annual report dated December 31, 1780, at San Diego, by Fathers Lasuen 

and Serra: 44

A few days ago we had a heavy rainfall which filled the river bed 

and the lowlands where the wheat and barley had been planted * # #. The 

Indiana are now working hard to remedy the trouble for the present and to 

prevent similar disasters in the future.

Little is recorded of the flood of 1811.

1815

In 1815 there was a flood that changed the course of the Los Angeles 

River within what is now the city limits of Los Angeles from the east to 

the west side of the valley. The river turned and ran down where Alameda 

Street now is, broke westward near Fourth and Fifth Streets and joined 

Ballona Creek, thence emptying into Santa Monica- Bay.

1821

A flood on the San Diego River in 1821 is reported by Smythe. 45

By the year 1821, the little patches of cultivated land had multiplied at the base of Presidio Hill and even spread up and across Mission 

Valley. Don Bias Aguilar, who was born in San Diego in 1811, recalled 15 

such rancherias, as they were called, which were occupied prior to the 

great flood of that year. At two places in the-valley there were vineyards. Most of the rancherias were washed away or greatly damaged by the 

flood, which occurred in September or October and in a single night filled 

the valley and changed the course of the river.

1822

In 1822 another great flood on the Los Angeles River covered all the 

lowlands and reached a greater height than was ever known before. 4 ^

Probably the greatest of the earlier recorded floods was that of 

1824-25, of which Warner 47 writes:

In 1825 the rivers of this country were so swollen that their beds, 

their banks, and the adjoining lands were greatly changed. At the date 

of the settlement of Los Angeles City a large portion of the country from 

the central part of the city to the tidewater of the sea, through and 

over which the Los Angeles River now finds its way to the ocean, was 

largely covered with a forest, interspersed with tracts of marsh. From 

that time until 1825 it was seldom, if in any year, that the river discharged, even during the rainy season, its waters into the sea. Instead 

of having a riverway to the sea the waters spread over the country, filling the depressions in the surface and forming lakes, ponds, and marshes.

44 Engelhardt, Father Zephyrin, Mission San Diego, p. 109, 1920.

45 Smythe, W. E., History of San Diego, p. 99, 1907.

46 McQlashan, H. D., and Ebert, F. C., Southern California floods 

of January 1916: U. S. Qeol. Survey Water-Supply Paper 426, p. 36, 1918.

47 Warner, J. J., Hayes, Benjamin, and Widney, J. P., Historical 

sketch of Los Angeles County, p. 17, 1876.
388 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

The river water, if any, that reached the ocean, drained off from the 

land at so many places, and in such small volume, that no channel existed 

until the flood of 1825, which by cutting a riverway to tidewater drained 

the marshland and caused the forests to disappear.

There are numerous references that testify to the fact that the Los 

Angeles River made the big change in its course during the flood of 1824- 

25. It was commonly understood and talked of in early days by old Mexican . 

settlers that, until the flood of 1825, the Los Angeles River flowed out 

through the southwest .part of the city into Ballona Creek and thence into 

Santa Monica Bay. But in 1825 the floods were probably the greatest for 

many years, causing the river to break eastward into San Pedro Bay. '

Pio Pico, former Governor of Alta California under the Mexican regime, and others have affirmed that up to 1825 the Los Angeles River 

flowed along the high bank just east of Main Street down to about Seventeenth Street, thence southwesterly into Cienega Creek, which in turn 

flowed into Ballona Creek.

J. R. Ramirez, who furnished the following account, was born in Los 

Angeles in 1839. His great-great-grandfather settled there in 1786, and 

this pioneer's descendants have lived on the old home place ever since. 

Mr. Ramirez says: 48

In those early days up to 1825 the river flowed along San Fernando 

Street, which is just below North Broadway at this point. In 1825, the 

floods were the greatest in the past 100 years. This flood filled the 

whole Los Angeles River Valley from the bank between North Broadway and 

San Fernando Streets to the Southern Pacific yards on the other side of 

the river. This flood changed the course of the Los Angeles River eastward from its old bank, along Main Street, to somewhere near Alamada 

Street. Its entire course was changed to the south side of the city. 

The river flowed out through Ballona Creek before this flood, but after 

this time it passed near the foot of the hills at Dominguez and into San 

Pedro Bay.

The flood of 1825 changed the course of the Santa Ana River also. 

Previous to that year the Santa Ana entered the ocean several miles to the 

northwest of its present channel.

1832

49 According to Warner, the flood of 1832 produced considerable change

in the contour of the country south of the city. He says:

The flood of 1832 so changed the drainage in the neighborhood of 

Compton and the northeastern portion of the San Pedro Ranch that a number 

of lakes and ponds, covering a large area of the latter ranch, lying north 

and westerly from Wilmington, which to that date had been permanent, became dry a few years thereafter.

The drainage of these ponds and lakes completed the destruction of 

the forests that Warner says covered a large part of the county south and

48 Ramirez, J. R., in Regan, J. W., op. cit., p. 142.

49 Warner, J. J., op. cit., p. 18.
HISTORY OP FLOODS IN SOUTHERN CALIFORNIA 389

weat of the city. Theae foreats were in all probability willow thicketa 

or copae, the aame as grew until quite recently on the low grounds near 

the mouth of the Santa Ana River and in the awampy landa along the San 

Gabriel River.

In Ventura County, the flood of 1832 deatroyed the chapel of San 

Miguel. This is the firat authentic record of flood damage along the 

lower reaches of the Ventura' River. Father Engelhardt atatea:^

Fr. Uria remarka, .in hia report (1832), that the chapel of San Miguel, 

the pride of Father Senan, could not be saved, the floods having destroyed 

it entirely.

1849 to 1860

Floods of various magnitude occurred in 1849-50, 1851-52, 1859-60.

1861-62

The flood of 1861-62, has been called the "great flood" and the 

"Noachian deluge of California floods." During the flood period in 1862 

the entire valley area from Los Angeles to the ocean, both toward San 

Pedro and toward Ballona, was a great lake. The Los Angeles River in the 

city of Los Angelea extended from Alameda Street to the bluff on the Pico 

Heighta aide. A little below Vernon, about where Vernon Avenue now la, 

the river aplit, and part of it went through Loa Cienagaa grant into 

Ballona Creek.

During the aame flood the San Gabriel River overflowed its banka, 

.broke from its course east of El Monte, and started a new channel to the 

west of El Monte, taking about the aame course aa later taken in 1867 to 

form what was then known as New River.

In San Bernardino, Riveraide, and Orange Counties, the Santa Ana 

River became a raging torrent during the flood of 1862. The prosperous 

coloniea along the banks of the river were completely inundated, and vineyards, orchards, and grain fields were transformed into a barren waste.

Flood waters of 1862 on the Ventura River are reported to have 

apread from the bluff on the Taylor Ranch to the hills east of Ventura 

Avenue, thus attaining a width of about 4,000 feet. Many houaea were aubmerged and aeveral destroyed. Parts of the old Mission waterworks, which 

brought water to Ventura, were destroyed.

50 Engelhardt, Father Zephyrin, San Buenaventura Mission, p. 68, 

1930.
390 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

In describing this flood, Guinn 51 states:

The great flood of 1861-62 was the Noachian deluge of California 

floods. The season's rainfall footed up to nearly 50 inches. The valley 

of the Sacramento was a vast inland sea. # * # In our country, on account of the smaller area of the valleys, there was but little loss of 

property. The rivers spread over the low lands, but stock found safety 

from the flood on the hills. The Santa Ana for a time rivaled the "Father 

of Waters" in magnitude. In the town of Anaheim, 4 miles from the river, 

the watier ran 4 feet deep and spread in an unbroken sheet to the Coyote 

Hills, 3 miles beyond. The Arroyo Seco, swollen to a mighty river, 

brought down from the mountains and canyons great rafts of driftwood which 

were scattered over the plains below 'the city and furnished fuel for the 

poor people of the city for several years. It began raining on December 

24, 1861, and continued for thirty days with but two slight interruptions. 

The "Star" published the following local: "A Phenomenon on Tuesday last 

the sun made its appearance. The phenomenon lasted several minutes and 

was witnessed by a. great number of persons."

An interesting account of this flood is given by Mrs. Crafts, 52 who 

says:

The fall of 1861 was sunny, dry, and warm until Christmas, which 

proved to be a rainy day. All through the holidays there continued what 

we would call a nice, pleasant rain, as it often rains in this section 

for days at a time. This much-needed moisture and wetting of the parched 

earth lasted until the 18th of January, 1862, when there was a downpour 

for 24 hours or longer. All the flat, from the Santa Ana River to Pine's 

hotel was under water, a perfect sea of water, inundating the valley for 

miles up and down the river, and Lytle Creek came rushing down D Street, 

across Third, finding an outlet through an open space into Warm Creek. 

Many families fled in the night to higher ground, losing everything they 

had stored away for the winter. * # * The constant rain on the adobe 

houses turned them to mud, and, of course, they fell to pieces.

Heavy rains extended into San Diego County, according to a report by 

Davis, 53 in which he states:

In the winter of 1861-62 unusually heavy rains fell in San Diego 

County, being 30 inches, the average fall for that section of the State 

being 9 inches.

1867-68

The flood of 1867-68 caused the San Gabriel River to break out of 

its channel and form New River. It broke out a little above the old 

Temple place and continued south, instead of making the turn toward the 

point of hills Just below Old Mission settlement, and all the water of 

the San Gabriel went into the New River. Several thousand acres of land 

were washed away. Willows had grown up so thick and large down by the 

Old Mission settlement that when the flood came it simply knocked the 

trees down and covered them up with sand and boulders,'forming .a barrier 

that changed the channel and caused the flow to pass by the Pico Rancho 

and on to Los Alamitos Bay.

51 Guinn, J. M., A history of California, p. 428, 1915.

52 Crafts, Mrs. E. P. R., Pioneer days in San Bernardino Valley, 

p. 71, 1906.

53 Davis, W. H., Seventy-five years in California, p. 335, 1929.
HISTORY OF FLOODS IN SOUTHERN CALIFORNIA 391

A short time before the founding of Downey, a small settlement named 

Galatin had been started nearby, but the flood of 1868 caused the otherwise dry rivers to change their courses and Galatin was washed away 54

Concerning the Santa Ana River, Brown and Boyd, 55 report as follows!

There was no further year of heavy rainfall until that of 1867-68, 

when the winter proved rainy, but, while the precipitation was continuous, 

it was not as heavy as in 1862, and as a result less damage resulted.

The Ventura River overflowed it£ banks, and according to Hobson, 56 

the whole of that portion of the town west of the point of the schoolhouse hill (unis location being a little north and east of the present 

junction of Main Street and Ventura Avenue) was submerged.

1884

No serious floods occurred from 1868 to 1884, a period of 16 years. 

Then southern California experienced a series of wet years, with floods 

in 1885, 1886, 1889, and 1891.

The flood of 1884 ranks among the major floods in fact, there were 

two floods in 1884. The first came the latter part of February; it did 

little damage, but a great quantity of water fell, apparently utilizing 

much of the absorptive capacity of the ground. A second flood came 

within 6 or 8 days after the first and did a great deal of damage. All 

the bridges across the Los Angeles River were washed out except one, the 

old Downey Avenue Bridge. Many houses were washed away, and several 

people drowned. The water broke out of the river banks and flowed toward 

Alameda Street, which was lower than the river bed; came up on First 

Street halfway between Los Angeles and Main Streets, and also flooded the 

lower part of the city. At Maple and Twenty-fourth Streets the water was 

between 3 and 4 feet deep. The flood waters flowed westward along the 

then Washington Road and Jefferson Street and thence southwest into Ballona Creek through which it reached Ballona Bay. All of the Cienega 

country became a great lake, and the country back of Venice a veritable 

sea.

San Fernando Valley was flooded from Chatsworth to Glendale. The 

Southern Pacific railroad was washed out in many places.

54 Newmark, Harris, Sixty years in southern California (1853-1913), 

p. 362, 1926.

55 Brown, John, Jr., and Boyd, James, History of San Bernardino and 

Riverside Counties, vol. 1, p. 145, 1922.

56 Hobson, W. D., unpublished manuscript, 1876.

454720 O - 42 - 26
392 FLOODS OP MARCH 1938 IN SOUTHERN CALIFORNIA

The Santa Ana River cut a new channel to the sea. Beginning at a 

point below where Santiago Creek enters the Santa Ana, the river cut 

through the fertile lands east of the old channel and discharged into the 

ocean about 3 miles southeast of its former outlet. According to Brown 

and Boyd 57

The year of 1884 proved to be the great flood year of later times, 

and 37.50 inches were reported during the season for San Bernardino, 

while over 40 inches were registered at Los Angeles and more at other 

points.

In San Diego County the flood of 1884 was very severe. Sraythe 58 

says:

Thus far all appeared to be going well, but there was more trouble 

in store for San Diego and its railroad hopes. In February 1884 a series 

of violent storms descended and literally destroyed the section of the 

railroad through Temecula Canyon.

The season of 1883-84 was the wettest winter on record in San Diego 

County, with 27.59 inches of rainfall at San Diego and 50.51 inches at 

Escondido.

In Ventura County, 30 inches of rain fell in 27 days, of which 6 

inches fell in 34 hours, causing the Ventura River to rise higher than it 

had been since the flood of 1867, It was estimated that 65 inches fell 

during February and March in the San Antonio Valley, whose drainage ia 

tributary to the Ventura River, causing the worst flood known in the valley. Casitas Bridge, crossing Ventura River at Foster Park, was washed 

out.

1886

Heavy rainfall with streams reaching flood stages and causing considerable damage was recorded in 1886-87. According to Newmark 59

The great flood of 1886 reached its first serious state on January 

19th. All of Los Angeles between Wilmington Street and the hills on the 

east side was inundated; levees were carried off as if they were so much 

loose sand and stubble, and for two or three weeks railway communication 

with the outside world was impossible.

1889

The flood of 1889 was comparable in magnitude to that of 1884. It 

came on Christmas Day, and the greatest damage occurred on that day. The 

Evening Express, Los Angeles, in its issue of December 26, 1889, says:

Much damage has been done in and about the city. Streets cut up, 

conduits filled with sand, bridges carried away, railroad tracks covered 

with dirt, and much other damage done.

57 Brown, John, Jr., and Boyd, James, op. cit., vol. 1, p.

58 Smythe, W. E., op. cit., p. 405.

59 Newmark, Harris, op. cit., p. 551.
HISTORY OF FLOODS IN SOUTHERN CALIFORNIA 393

The approaches to the Kuhrts Street bridge were washed away. About 

half the Santa Fe bridge over the Los Angeles River swept away and dashed 

against the Buena Vista bridge, weakening the piers and badly damaging it. 

The S. P. [Southern pac ifio] pile bridge, below Kuhrts Street Bridge, almost entirely carried away. The 7th and 9th street bridges so badly 

damaged as to render them unserviceable.

The storm was general all pver the southern section of the State. No 

trains on the Santa Fe or S. P. have either arrived or departed except one 

to Santa Monica. Levees in numerous places have been washed away.

The country between this city and the sea is in many places covered 

by water, and -uany ranchers will lose heavily. The extensive vegetable 

gardeners south of the city will lose heavily.

At Compton the water is very high. The citizens resorted to boats 

and made their way about town in that way. The country in that vicinity 

is flooded, and it will be weeks before the surface will-be dry.

Hon. H. T. Gage says that the new San Gabriel, the old San Gabriel, 

and the Los Angeles Rivers have formed one body near Downey and are sweeping toward the ocean, carrying everything with them. On the Laguna Ranch 

a lake 5 miles in width has formed, and the water nearly to the top of the 

hay stacks. The Los Angeles River, 2 miles below the city has swerved 

from its channel and is running down the Downey Road.

1891

In 1891, floods were recorded on the Santa Ana River and some of its 

tributaries, and on the San Luis Rey River above Bonsall. 60

1909

The following extract from the Riverside -Daily Press gives an account 

of a flood on the Santa Ana River in 1909:

December 31, 1909.- Santa Ana River was at its highest flood stage in 

20 years. Portions of the Crestmore Electric Railroad line bridge, between Riverside and Crestmore, washed out. Chinese truck gardens, roads, 

crops, trees, fences, and farm buildings in the path of the flood were 

washed out. Head works of the power company's canal at the Salt Lake 

Railroad bridge washed out. # # # Barn on the Voorhes Ranch, above the 

Salt Lake Railroad bridge, was washed away. Flood waters destroyed Evens 

Lake and dam below the bridge on the west side of the river. Ranch homes 

threatened. Many large cottonwood trees were uprooted and carried downstream.

Between Menifee and Ethanac, flood waters rushing off the San Jacinto 

Mountains into San Jacinto River and Bautista Canyon Creek washed out the 

Santa Fe Railroad. Heavy runoff through Cajon Pass caused landslides on 

Santa Fe Railroad along a stretch of 13 miles between Summit and Devore 

stations. All train schedules abandoned. At Etiwanda, the Santa Fe Railroad washed out. Same road badly damaged at East Highland by rush of 

flood water off the San Bernardino Mountains. Railroad service between 

San Bernardino and Los Angeles abandoned.

With reference to this same storm, the San Bernardino Sun for January 

1, 1910, sayss

At 2 o'clock this morning, storm and flood conditions are quite serious. Rain was falling in torrents. Unless relief comes by daybreak, 

damages will run into thousands of dollars. Engine and three coaches of 

work train turned over 1 mile north of Devore.

The Santa Fe Railroad roundhouse at San Bernardino surrounded by 

floodwater and that city has suffered more severely from floodwater than 

at any time in its history.

Approaches to Colton Avenue Bridge, Pacific Electric bridge, washed 

out. Colton entirely cut off from outside world. Lytle Creek out of its 

channel and threatening Salt Lake Railroad shops at Colton. # # #

60 Surface water supply of the Pacific slope of southern California: 

U. S. Geol. Survey Water-Supply Paper 447, pp. 549, 550, 1921.
394 FLOODS OF MARCH 1938 IN SOUTHERN CALIFORNIA

The Southern Pacific "newspaper special train" from Los Angeles 

plunged into the Santa Ana River while crossing the bridge near Colton. 

Floodwaters had undermined piling of the bridge. Two coaches toppled 

over on the 30-inch pipe line of the Riverside-Highland Water Co., breaking it. Two sections of the pipe line toppled into the river when the 

cement piers crumbled under the force of the raging stream.

Traffic on the Santa Fe Railroad through the Santa Ana River canyon 

was abandoned because of landslides.

At San Jacinto, floodwaters out of the San Jacinto River and Bautiste 

Creek canyon ripped bad breaks in the river levee near San Jacinto and the 

lowlands between Oilman Hot Springs and Railroad Canyon Dam of the Temescal Water Co. near Elsinore were badly flooded. Four inches of rain fell 

at Lake Hemet, raising the water in the lake to 112 feet.

Because of the washout of the approach to the West Riverside Bridge 

on the west side of the Santa Ana River, entrance to Riverside was by way 

of the Salt Lake Railroad bridge and by way of Colton. Two spans of the 

Crestmore trolley line bridge were washed out.

1911

In March 1911 there was a serious flood on the Ventura River. January and February of that year were rainy months. Although no excessive 

downfall occurred, the soil was wet and conditions were ripe for a rapid 

runoff following the heavy rain of March 9. According to the Ventura 

Free Press for March 9, 1911,

The Ventura River perhaps was never higher. It is overflowing its 

banks from Casitas to the sea. The Casitas Bridge, 17 feet above the 

water at normal flow, is under water; the Avenue is awash; the western 

part of Ventura is under water; at 3:15 the big steel bridge [[Southern 

Pacific Railroad] broke and 50 feet of the structure went down and out 

into the ocean.

1914

Floods of January and February 1914 were very destructive in southern 

California and were responsible for increased interest in stream-flow 

records. Water-Supply Papers 391 and 447 contain estimates of peak discharges available for this period.

1916

The flood of 1916 is covered by Geological Survey Water-Supply Paper 

426, 'Southern California floods of January, 1916, by H. D. McOlashan and 

F. C. Ebert.

1916 to 1938

No major floods occurred in the southern California region between 

1916 and 1938, except the flood of January 1, 1934, which did considerable 

damage in La Canada Valley area. This flood is .described in Water-Supply 

Paper 796-C, Flood in La Canada Valley, California, January 1, 1934, by 

Harold C. Troxell and John Q. Peterson. Minor floods, causing damage in 

certain areas, occurred during 1918, 1921-22, 1926, 1927, 1931, 1932, 

1934, 1936, and 1937.
GEOLOGICAL SURVEY

WATER-SUPPLY PAPER 844 PLATE 21

SANTA ANA RIVER BELOW LOWER SANTA ANA CANYON, MARCH 3, 1938.

Courtesy of Fairchild Aerial Surveys, Inc.

GEOLOGICAL SURVEY

WATER-SUPPLY PAPER 844 PLATE 22

SANTA ANA RIVER AT MOUTH OF CHINO CREEK, MARCH 3, 1938.

Courtesy of Fairchild Aerial Surveys, Inc.

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 23

SANTA ANA RIVER NEAR NORCO, MARCH 3, 1938.

Courtesy of Faiichilrl Aerial Surveys, Inc.

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 24

BREAK IN LEVEE OF SANTA ANA RIVER, MARCH 3, 1938.

Note development of debris cone, lower right, which formed bank of new channel. Courtesy of Fairchild Aerial Surveys, Inc.

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 25

"1

OVERFLOW AREA ALONG SANTA ANA RIVER, MARCH 3, 1938.

Courtesy of Faircllild Aerial Surveys, Inc.

GEOLOGICAL SURVEY WATER-SUPPLY PAPER 844 PLATE 26

^m^m^^m^y^m^- ' MT , .-?'~*'i?^Pf>ff.r'>j'f.>fff.tf*fff*'frrfjFf':^r - ^^

-J

FLOODED CITRUS AND WALNUT GROVES ALONG SANTA ANA RIVER, MARCH 3, 1938.

Courtesy of Fairchild Aerial Surveys, Inc.

INDEX 395

Page 

Acknowledgments .......... 3-4

Administration and personnel. . . . 2-3

Alhambra Wash, at Alhambra. .... 259

Allso Creek, at El Toro ...... 203-204

Allso Creek Basin,discharge In . 203-204,289 

rainfall In ............ 18-19

Alluvial cones, character of. ... 337-338

origin of ............ 301

Altitude, precipitation In relation

to. ........... 47-60,82-93

Arrowhead Springs, Strawberry Creek

near. ............ 211

Waterman Canyon Creek near. . . . 212

Arroyo San Onofre Basin, discharge

In. ............. 289

Arroyo Seoo, near Pasadena. .... 254

Artesla, Coyote Creek near. .... 239

Azusa, Rogers Creek near. ..... 232-233

San Sabriel River

near. . . . .106-109,229-230,pi. 17,A

Baldwin Park, Walnut Creek near . . 237

Ballona Creek, near Culver City . . 264

Ballona Creek Basin, discharge

In. ........... 263-265,295

floods in, previous ....... 389-390

Barstow. Mojave River at. ..... 284

"Basin, meaning of, in parts of

report. ............ 137

Benedict Canyon storm drain at

Culver City ......... 265

Bonsall, San Luis Rey River near. . 197-198

Boulder Creek, at Cuyamaoa Reservoir, near Julian ...... 194

Brea Creek, at Pullerton. ..... 240

Brown, John, Jr., and Boyd, James,

quoted. ........... 391,392

Browns Creek at Chatsworth. .... 246-247

Cajon Creek, near Keenbrook .... 217-218

Cajon Creek Basin, physiographic

and geologic features of. . . 318-319 

Calabasas, Malibu Creek near. . . . 267

Oalleguas Creek Basin, discharge

in. ........... 129-133,296

rainfall in ...... 36-37,72-73,77,80

Camp Bonlta, East Fork of San

Sabriel River near. . 174-176,228-229 

West Fork of San Sabriel River

near. .......... 109-111,232

Campo Creek, near Campo ...... 190-191

Carbon Creek, at Olinda ...... 241

Carpinteria Creek Basin, discharge

in. ............. 298

Centinela Creek, near Culver City . , 263 

Chatsworth, Browns Creek at .... 246-247

Chino Creek, at mouth ....... pi. 22

near Prado. ........... 223-224

Chlno Valley, rainfall in . .28,43,70,77,80 

City Creek, near Highland . . . 176-180,213 

Claremont, San Antonio Creek

near. ....... .224-225,pi. 18,A

Thompson Creek near ........ 120-121

Coastal plains, physiographic and

geologic features of. .... 338-339

rainfall in .... ..'51-35,44,71-72,77,80

Colby Ranch, Tujunga Creek near . . 248 

Colton, debris deposits in. .... pi. 3

Lytle Creek at. ......... 216-217

Warm Creek near ......... 210

Cones, alluvial, origin and

character of. ...... 301,337-338

debris, origin and control of . . 372 

Contracted openings, flow through,

computation of. ....... 172

Corona, Temescal Creek near .... 223

Cottonwood Creek, above Tecate

Creek, near Dulzura ..... 187-188

at Horena Dam .......... 186

near Dulzura. .......... 186-187

Coyote Creek (San Sabriel River

Basin), near Artesia. .... 239

Coyote Creek (Ventura River Basin),

near Ventura. ........ 274

Craftonville, Mill Creek near . . . 207 

Crafts, Mrs. E.P.R., quoted .... 390

Crespi, Father Juan, quoted .... 386

Page

Cucamonga Creek, near Upland .21P-220,pl. 17,B

Culver City, Ballona Creek near . . 264

Benedict Canyon storm drain at. . 265

Centinela Creek near. ...... 263

Cuyama River, near Santa Maria. . . 280

D

Daingerfield, L. H., quoted .... 6,47

Dalton Creek, at flood-control

reservoir near Slendora . . . 117-118 

near Slendora .......... 235

physiographic and geologic

features of ......... 333-334

Davis, W. H., quoted. ....... 390

Day Creek, near Etiwanda. ..... 219

Debris, deposition of, in reservoirs and debris basins . . . 372-376 

effect of, on discharge ..... 100-101

movement of ......... 169,377-381

views showing ........ .pis. 3, 6,

10,B, 16,A, 20,A 

Debris basins, deposition in. . . . 372-376

views of. ........ .pis. 9, 19, 20

Debris cones, artificial channels

across. .......... 13, pi. 9

origin and control of ...... 372

Deep Creek, near Hesperia .282-283, pi. 18,B 

Del Rosa, maximum precipitation

periods at. ......... 179

Devil Canyon, maximum precipitation

periods at. ......... 179

Devil Canyon Creek, near San

Bernardino. ......... 214

Discharge, into reservoirs, graphs

showing ........... 104

peaks of, computation of. 131-136,168-174 

in relation to artificial

storage ........... 369-371

in relation to retention. . . . 181

summary of. .......... 286-299

records of. ....... .98-130,183-285

basic, definition of. ..... 98-99

consistency of. ........ 182-183

continuous, computation of. . . 174-176 

effect of debris on ...... 100-101

in .relation to basin characteristics and rainfall. . . . 136-167

methods of obtaining. . .98-103,168-184 

See also Runoff; Stage and discharge; names of streams and 

gaging stations.

Downey, Loa Angeles River near. . . 245 

Rio Hondo near. ......... 262

Drainage basins, area above floodcontrol dams. ........ 136-139

debris in, accumulation and movement of ........... 372-381

in flooded region, map showing. . 8 

physiographic and geologic

features of. . .139-140,149-167,300-350 

See also Rainfall; Runoff; names

of basins. 

Duarte, Fish Creek near ...... 233

Dulzura, Cottonwood Creek near. . . 186-188- 

Tia Juana River near. ...... 188-189

Dunsmuir debris basin, 372-373, 

features cf. .... pis. 9,A, 19, 20

E

Eagle-Soss debris basin, outlet

channel from. ......... pi. 9,B

East Highlands, Plunge Creek near . 208

rainfall in ........... 29

Eaton Creek, at flood-control reservoir near Pasadena. ..... 127-128

near El Monte .......... 257

near Pasadena .......... 256

El Monte, Eaton Creek near. .... 257

Rio Hondo near. ......... 260

El Toro, Allso Creek at ...... 203-204

Elsinore, San Jaclnto River near. . 221-222 

Elslnore Lake at Elsinore ..... 222-223

Engelhardt, Father Zephyrin, quoted. 387,389 

Etiwanda, Day Creek near. ..... 219

East Etiwanda Creek near. . . . .pi. 16,A

Evapo-transpiration, effect of, on

retention .......... 351-352

Evening Express, of Los Angeles,

quoted. ........... 392-393
396 INDEX

Page 

Pall Brook, Santa Margarita River

near. ............ 2CO-201

Fern Canyon plots, rainfall and

runoff on ........... 166-167

Pern Canyon Watershed No. 8, near

San Dlmas .......... 114

Pern Canyon Watershed No. 3, near

San Dlmas .......... 114-115

Pern Canyon watersheds, description

of. ........... .101,pi. 15

rainfall and runoff on. . 158,154-155,167 

Fill, In stream channels. See

Scour and fill. 

F11]more, Sespe Creek near. .... 870

Pish Creek, near Duarte ...... 833

Flood of March 1938, damage caused

by. . .13-14,381-384,pis. 1-8,10,81-86 

general features of ....... 4-14

region affected by, maps showing. 5,8 

Flood-control dams, rainfall, runoff, and retention at .... 148-145

Floods, In southern California,

history of. ......... 385-394

previous, In Ballona Creek Basin . 389-39C 

In La Canada Valley ...... 394

In Los Angeles River Basin. . . 3S6-393 

In San Diego River Basin. . . . 387,398

In San Gabriel River

Basin ........ 386,389-390,393

In San Luls Rey River Basin . . 3P3 

In Santa Ana River Basin. . . . 388-394

In Venture River Basin . 389-390,398,394 

Flood-control reservoirs, debris

In. ......... 100-101,372-376

discharge Into. ..... 103-104,131-136

effectiveness of. ........ 369-371

on Dalton Creek near Glendora . . 117-118 

on Eaton Creek near Pasadena. . . 187-188 

on Little Santa Anita Creek near

Sierra Madre. ........ 186-189

on Live Oak Creek near La Verne . 118-119 

on Pacolma Creek near San Fernando. 181-188 

on San Dimas Creek near San Dlmas. .118-113 

on San Gabriel River near Azusa . 106-103 

on San Gabriel River, West Fork

of, near Camp Rlncon. .... 109-111

on Santa Anita Creek near Sierra

Madre ............ 124-186

on Santiago Creek near Villa

Park. ............ 105-106

on Sawplt Creek near Monrovia . . 111-112

on Thompson Creek near Claremont. 120-181

on Tujunga Creek near Sunland . . 183-184

Flood plains, character of . 301-308,338-339

Fontana, Lytle Creek near ..... 815

Foster, San Vlcente Creek at. . . . 195

Fullerton, Brea Creek at. ..... 240

Gage heights, records of. ..... 183-885

Gaging stations. See Stream-gaging

stations.

Geologic features of the area . . . 300-350 

Glendale, Verdugo Creek at. .... 858-853

Glendora, Dalton Creek near . . 117-118,835

Little Dalton Creek near. .... 836 

Great Basin, discharge In ..... 899

rainfall In ........... 41

"Great" flood, accounts of. .... 389-390

Gulnn, J. M., quoted. ....... 390

H

Halnes Creek near Tujunga ..... 251 

Hall Creek Basin, discharge In. . . 297 

Hesperla, Deep Creek near . 282-283,pi. 18,B

West Fork of Mojave River near . . 285 

Highland, City Creek near . . . 176-180,813 

Honda Barranca, at Berylwood Road,

near Somls. ......... 189

at Perklns Road, near Somls . . . 129-130 

Huasna River, near Santa Maria. . . 280-281 

Huntlngton Beach, flooded area near. pi. 2 

Hydrologlo conditions In the area. . 15-97

I

Infiltration, relation of, to

retention and runoff. .... 166-167

Page 

Irvine Ranch drainage canal near

Tustln. ........... 887-888

Isohyetal maps, of San Dlmas

Experimental Forest ..... 57

of southern California. . . . .pis. 11-13,

(In pocket),14 

preparation of.......... 46-49

J .

Julian, Boulder Creek near. .... 194 

Jurupa Basin, rainfall

In. ........ 89,44,70-71,77,80

K

Keenbrook, Cajon Creek near .... 817-818 

Lone Pine Creek near. . .171,818,pi. 16,B

La Canada Valley, flood In. .... 375,394

Lag, between rainfall and runoff. . 168-166 

Laguna Creek Basin, discharge In. . 889 

Lake Hodges, San Dlegulto River at. 197 

Lakeside, San Diego River near. . . 198-193 

La Verne, Live Oak Creek near . . . 118-119 

Life, loss of, by flood ...... 388

Little Dalton Creek, near Glendora. 836 

Little Santa Anita Creek, near

Sierra Madre. ...... 186-187,855

Little Tujunga Creek, near San

Fernando. .......... 850

Live Oak Creek, at flood-control

reservoir near La Verne . . . 118-119 

Live Oak Creek Basin, rainfall, 

runoff, and retention 

In. ......... 143,145,151-153

Location of region affected by

flood ............ 4,5

Lompoc, Santa Ynez River near ... 879 

Lone .Pine Creek, near

Keenbrook ..... .171,818,pi. 16,B

Lone Pine Creek Basin, physiographic

and geologic features of. . . 319-381 

rainfall, runoff, and retention In. 358 

Long Beach, Los Angeles River at. . 846 

Los Alamltos, San Gabriel River

near. ............ 831

Los Angeles, Los Angeles River at .244,pi. 7

Los Angeles River, at Long Beach. . 846

at Los Angeles. ........ 244,pi. 7

channel of, scour and fill In . . 379-380 

near Downey ........... 245

near Universal City ....... 243

near Van Nuys .......... 848

Los Angeles River Basin, area above

flood-control dams In .... 137-139

discharge In. ...... 121-188,248-868

peaks of. ....... 132-135,893-895

floods In, previous ....... 386-393

physiographic and geologic 140,328-327, 

features of ..... 330-335,337-339

rainfall In .... 19-35,48-44,55,63-78,

75-77,79-81,82-83,150, 

156-157,368-363,364-367 

reservoirs In, storage and

flow at ........... 370-371

retention In. .... .181,368-363,364-367

runoff In ..... .134,147,150,156-157,

164,368-363,364-367 

Lytle Creek, at Colton. . . . 816-817,pi. 3

at San Bernardlno ........ 815-816

near Fontana. .......... 815

Lytle Creek Basin, physiographic

and geologic features of. . . 335-337 

rainfall, runoff, and retention

In. ............. 357-358

M

Mallbu Creek, at Crater Camp, near

Calabasas .......... 867

Mallbu Creek Basin, discharge In. . 267-296 

rainfall In .... .36-37,45,78-73,77,80

Manning formula, use of, In computing peak discharge .... 169-170

Matlllja Creek, at Matlllja .... 272

Mentone, Santa Ana River near . . . 204-805 

Mesa Orande, Santa Ysabel Creek near . 196
INDEX 397

Page

Meteorologlc conditions In the area. 15-97 

Mill Creek, near Craftonville ... 207 

Hill Creek Basin, physiographic and

geologic features of. .... 315-317

rainfall, runoff, and retention

In. ............. 357-358

Mission Acres, Pacolma Creek at . . 247-248 

Mission Fathers, records by, on

floods. ......... 386,387,389

Mojave River, at Barstow. ..... 284

at lower narrows, near Vlctorvllle ............ 283

West Fork of, near Hesperla . . . 285 

Mojave River Basin, discharge

In. ........... 282-285,299

physiographic and geologic

features of ......... 307-312

rainfall in ........... 41

Monrovia, Sawpit Creek near . . 111-112,234 

Montebello, Rio Hondo near. .... 261

Monteclto, Santa Ynez River near. . 275 

Morena Dam, Cottonwood Creek at . . 186 

Morris Reservoir, records at. ... 108-109

Mount Isllp, precipitation near '. . 47,48 

Murrleta Oreek, at Temecula .... 201-202

N 

Nestor, Tla Juana River near. . . .

Newmark, Harris, quoted ......

Norco, Santa Ana River near ....

0

Oceans ide, San Luls Rey River at. , 

Ollnda, Carbon Creek at ......

Orange, Santiago Creek near ....

Otay River, at Savage Dam .....

Otay River Basin, discharge In. . , 

physiographic and geologic

features of .........

rainfall in. ......... 16,

189-190

392

pi. 23

198-199

241

pi. 5

191

191,287

304-307 

42,63,75

Pacific slcpe basins, discharge In,

peaks of. .......... 287-298

Paccima Creek, at flood-control

reservoir near San Fernando . 121-122 

at Mission Acres. ........ 247-248

near San Fernando ........ 247

Pacoima Creek Basin, physiographic

and geologic features of. . 330-331 

Pala, San Luis Rey River near ... 306 

Palm Canyon Creek, near Palm Springs 281-282 

Pasadena, Arroyo Seco near. .... 254

Eaton Creek near. ...... 127-128,256

Pendergast, J. J., quoted ..... 96

Personnel ............. 2-3

Physiographic and geologic features

of the area ......... 300-350

Plco, San Gabriel River at. .... 230-231

Plru Creek, near Plru ....... 269

Piru Creek Basin, physiographic and

geologic features cf. .... 344

Plunge Oreek, near East Highlands . 208 

Prado, Chlno Creek near ...... 223-224

Santa Ana River near. . . 205-206,377,378 

Precipitation. See Rainfall; Snow. 

Precipitation staTTons. See Rain

gages.

R

Rain gages, distribution and

grouping of .... 46-50,61-62,82-90

precipitation at. ...... 16-45,61-90

Rainfall, altitude In relation

to. ........... 47-60,82-93

antecedent to storm of Feb. 27-

Mar. 4, 1938. ..... 95-96,353-358

chronologic distribution of,

Feb. 27-Mar. 4, 1938. .... 58-61

dally ............ 16-46,63-74

hourly. ..... 60,63-90,150-162,pi. 14

Infiltration of ......... 166-167

intensity of. .......... 58-95

Isohyetal maps showing. .... .46-49,54,

57-58,pls. 11-13(in pocket),14 

local characteristics of. .... 49-54

maximum ....... 58-62,79-95,162-165

records of, collection of .... 14

Page 

Rainfall Continued.

retention of. ...... 166-167,351-369

runoff in relation

to. ..... 136-167,176-179,351-369

Ramlrez, J. R., quoted. ...... 388

Ramona, Santa Ysabel Creek near . . 306 

Rating curves, computation of peak

discharge from. ....... 172-174

Redlands, San Tlmoteo Creek near. . 209 

Reservoirs, records

at. ... 105-113,117-128,194,221,275

See also Flood-control reservoirs;

Storage. 

Retention, definition of. ..... 351

factors affecting ........ 353-358

relation of, to evapotransplration ........ 351-352

to Infiltration ........ 166-167

to peak discharge ....... 181

to rainfall ...... 140-149,351-369

to runoff ....... 140-149,351-369

Rio Hondo, near Downey. ...... 262

near El Monte .......... 260

near Montebello ......... 261

Riverside Daily Press, quoted . . . 393 

Rogers Oreek, near Azuaa. ..... 232-233

Rosemead, Rublo Canyon Wash at. . . 258 

Rublo Canyon Wash at Rosemead . . . 258 

Runoff, characteristics cf. . . . . 140-149

lag between precipitation and . . 162-166 

physiographic and geologic

features affecting. . 136-140,300-350 

records of collection of. .... 14

relation of, to artificial

storage ........... 369-371

to infiltration ........ 166-167

to rainfall ..... .140-166,176-179,

306,351-369 

to retention. ..... 140-149,351-369

S

Salton Sea Basin, discharge in .279,281-282 

physiographic and geologic

features of ......... 307-311

San Antonio Creek, near

Claremont ..... .224-225,pi. 18,A

San Antonio Creek Basin,

physiographic and geologic

features of ......... 332-333

rainfall, runoff, and retention

in. ............. 357-358

San Bernardino, Devil Canyon Creek

near. ............ 214

Lytle Creek at. ......... 215-216

San Bernardino mountain area,

physiographic and geologic

features of ......... 307-321

rainfall In ...... 23,43,67,76,79,84

San Bernardino Sun, quoted. .... 393-394

San Bernardino Valley, physiographic

and geologic features of. . . 337-338 

San Diego area, physiographic and

geologic features of. .... 302-307

San Diego River, at El Cap!tan Dam,

near Lakeside ........ 192-193

near Santee ........... 193-194

San Diego River Basin, discharge

in. ...... T ... 192-195,287-288

floods in, previous ....... 387-392

physiographic and geologic

features cf ......... 304-307

rainfall, runoff, and retention

in. .......... 16-17,358-364

San Dieguito River, at Lake Hodges. 197 

San Dieguito River Basin, discharge

In. ........... 196-197,288

physiographic and geologic

features of ......... 304-307

rainfall, runoff, and retention

in. .... 16-17,358-359,360-361,364

San Dimas, Fern Canyon watersheds

near. ............ 114-115

San Dlmas Creek near. .... 112-113,234

West Fork of San Dimas Creek

near. ............ 116

Wolfskill Creek near. ...... 115-116

San Dimas Creek, at flood-control

reservoir near San Dimas. . . 112-113
398 INDEX

Page 

San Dlmas Creek Continued.

near San Dimas. ......... 234

West Pork of, near San Dlmas. . . 116 

San Dlmas Creek Basin, discharge In. 131,180 

physiographic and geologic

features of ......... 333-334

rainfall and runoff In. ..... 154

San Dimas Experimental Forest,

infiltration experiments in . 166-167 

rainfall in ........... 54-58

San Fernando, Little Tujunga Creek

near. ............ 250

Pacoima Creek near. ..... 121-122,247

Tujunga Creek near. ....... 249-250

San Fernando Valley, physiographic

and geologic features of. . . 337-338 

rainfall In ...... 23,25,43,67,76,80

view of ............. pi. 8

San Gabriel mountain area,

physiographic and geologic

features of ......... 322-338

rain gages in .......... 48

rainfall In ........ .19-23,42-43,

63-67>75-76,79,84 

San Gabriel River', at flood-control

reservoir No. 1, near Azusa. . 106-108 

at Foothill Boulevard, near

Azusa ............ 229-230

at Morris Reservoir, near Azusa . 108-109 

at Pico ............. 230-231

at Spring Street, near Los

Alamitos. .......... 231

channel of, scour and fill in . . 380 

East Fork of, near Camp

Bonita. ....... 174-176,228-229

profile of. ........... 10

gaging station on ....... .pi. 17,A

West Fork of, at Camp Rinoon. . . 232 

at flood-control reservoir No.2,

near Camp Rincon. ...... 109-111

rainfall and runoff on. .... 142,153

San Oabriel River Basin, area above

flood-control dams in .... 137-139

discharge in. ...... 106-121,228-241

peaks of. ....... 132-135,291-293

floods in, previous . . . 386,389-390,393 

physiographic and geologic

features of ... 140,327-330,337-338 

rainfall in .... 19-35,42-44,55,63-72,

75-77,79-81,82-83,142,150, 

153,156-162,360-363,364-367 

reservoirs in, storage and

flow at ........... 366-371

retention in. .... 181,360-363,364-367

runoff In ..... .134,142,146,150,153,

156-162,180,181,360-363,364-367 

San Oabriel Valley, physiographic

and geologic features of. . . 337-338 

rainfall in .... .25-27,43,68-69,76-80

San Jacinto, San Jacinto River near. 220 

San Jacinto River, at Railroad 

Canyon Reservoir, near 

Elsinore. .......... 221

near Elsinore .......... 221-222

near San Jacinto. ........ 220

San Jacinto River Basin, rainfall

in. ............. 29-30

San Jose Creek, near Whittier . . . 238 

San Juan Capistrano, San Juan Creek

near. ............. 202

Trabuco Creek near. ....... 202-203

San Juan Capistrano Creek Basin,

rainfall in ......... 18-19

San Juan Creek, near San Juan

Capistrano. ......... 202

San Juan Creek Basin, discharge

in. ........... 202-603,289

San Luis Oblspo Creek Basin,

rainfall in .... 39-40,45,74,77,80

San Luls Rey River, at Oceanside. . 198-199 

at Pala ............. 306

near Bonsall. .......... 197-198

San Luis Rey River Basin, discharge

in. ........... 197-199,288

floods in, previous ....... 393

physiographic and geologic

features of ......... 303-307

rainfall, runoff, and retention

in. .......... 18,56,358-364

San Rafael Hills, rainfall

in. ......... .25,43,68,76,80

San Tlmoteo Creek, near Redlands. . 209

Page 

San Vlcente Creek, at Foster. ... 195

Santa Ana, Santa Ana River at ... 206-207 

Santiago Creek at ........ 226-227

Santa Ana River, at Santa Ana . . . 206-207 

channel of, scour and fill In . . 377-379 

near Hentone. .......... 204-205

near Prado. ....... 205-206,377,378

profile of. ........... 9

views of. ....... .pis. 1,2,4,21-26

Santa Ana River Basin, discharge

In. ..... 105-106,204-228,377-378

discharge in, peaks

of. ....... 132,134,135,289-291

floods In, previous ....... 388-394

physiographic and geologic 140,307-311, 

features of ..... 312-327,331-339

rainfall In .... 19-35,42-44,56,63-72,

75-77,79-81,82-83,150, 

360-361,364-367 

reservoirs in, storage and flow

at. ............. 369-371

retention In. .... 181,360-361,364-367

runoff In . . 134,150,180,360,361,364-367 

Santa Anita Creek, at flood-control

reservoir near Sierra Madre . 124-125 

near Sierra Madre ........ 255

Santa Anita Creek Basin, rainfall,

runoff, and retention in. . . 351-357 

Santa Barbara, Santa Ynez River

near. ............ 276-277

Santa Clara River, near Saugus. . . 268 

Santa Clara River Basin, discharge

In. ......... 268-271,296-297

physiographic and geologic

features of ..... 322-327,340-346

rainfall, runoff, and retention

In. ........... 362-363,368

Santa Margarita River, at Ysidora . 201 

near Fall Brook ......... 200-201

Santa Margarita River Basin,

discharge in. .....*. 199-202,288

physiographic and geologic

features of ......... 304-307

rainfall, runoff, and retention

in. ....... .18,358-359,360-361

Santa Maria, Cuyama River near. . . 280 

Huasna River near ........ 280-281

Santa Maria River Basin, discharge

in. ........... 280-281,298

physiographic and geologic

features of ....... 340-342,350

rainfall, runoff, and retention

in. ...... 39-40,362-363,368-369

Santa Paula Creek, near Santa Paula. 271 

Santa Ynez, Santa Ynez River near. . 278 

Santa Ynez River, at Juncal Reservoir, near Monteclto. .... 275

below Oibraltar Dam, near Santa

Barbara ........... 277

near Lompoc ........... 279

near Santa Barbara. ....... 276

near Santa Ynez ......... 278

Santa Ynez River Basin, discharge

In. ........... 275,279,298

physiographic and geologic

features of ..... 340-342,348-349

Santa Ynez River Basin, rainfall, 

runoff, and retention 

In. ...... 39-40,362-363,368-369

Santa Ysabel Creek, near Mesa

Qrande. ........... 196

near Ramona ........... 306

Santee, San Diego River near. . . . 193-194

Santiago Creek, at Santa Ana. . . . 226-227

at Santiago Reservoir, near

Villa Park. ......... 105-106

flooded lands along ....... pi. 5

near Orange ........... pi. 5

near Villa Park ...... 225-226,pi. 5

Santiago Creek Basin, rainfall

in. ......... .30,44,70,77,80

Santiago Reservoir, records at. . . 105-106 

Saugus, Santa Clara River near. . . 268 

Savage Dam, Otay River at ..... 191

Sawpit Creek, at flood-control

reservoir near Monrovia . . . 111-112 

near Monrovia .......... 234

Scour and fill, in stream

channels. ...... 174-176,377-380

Sespe Creek, near Fillmore. .... 270

Sespe Creek Basin, physiographic

and geologic features of. . . 344-345
INDEX 399

Page 

Sierra Hadre, Little Santa Anita ,

Creek near. ....... 126-127,255

Santa Anita Creek near. . . . 124-125,255

Slope-area method,computation of

peak discharge by ...... 169-171

typical reach, used in application

of. ............ .pi. 16,B

Smythe, W. E., quoted ....... 387,392

Snowfall, records of. ....... 96-97

Somis, Honda Barranca near. .... 129-130

Stage and discharge, records of . . 183-285 

relation between. ........ 172-175

Storage, artificial,'effect of, on

flood discharge ....... 369-371

Storm or Feb. 27-Mar. 4, 1938,

damage caused by. ...... 382-384

general features of ....... 4-14

movement of ..... .58-59,93-95,pi. 14

rainfall and retention preceding . 351-358 

region affected by, maps showing. 5,7,8 

Strawberry Creek, near Arrowhead

 Springs ........... 211

Strawberry Creek Basin, rainfall,

runoff, and retention in. . . 351-357 

Stream-gaging stations, stage and

discharge at, records of. . . 183-285 

views of, after reconstruction, pis. 17,18 

Sweetwater River, at Sweetwater

Dam ............. 192,306

Sweetwater River Basin, discharge

in. ............. 192,287

physiographic and geologic

features of ......... 304-307

rainfall in ......... 16,42,63,75

Sunland, Tujunga Creek near . . 123-124,249

T

Temeeula, Murrieta Creek at .... 201-202

Temecula Creek near ....... 199-200

Temeeula Creek, at Nigger Canyon,

near Temecula ........ 199-200

at Railroad Canyon, near

Temecula. .......... 200

Temeeula Creek Basin, rainfall in . 56 

Temescal Creek near Corona. .... 223

Temescal Creek Basin, rainfall in . 30 

Thompson Creek, at flood-control

reservoir near Claremont. . . 120-121

Tia Juana River, near Dulzura . . . 188-189

near Nestor ........... 189-190

Tia Juana River Basin, discharge

in. ........... 186-191,287

physiographic and geologic

features of ......... 304-307

rainfall in ......... .16,42,63,75

Topanga Creek, near Topanga Beach . 266

Page

Topanga Creek Basin, discharge in . 266,296 

rainfall in ...... 36-37,72-73,77,80

Trabueo Creek, near San Juan

Capistrano. ......... 202-203

Transpiration. See Evapotranspiration. 

Tujunga, Haines Creek near. .... 251

Tujunga Creek, at flood-control

reservoir near Sunland. . . . 123-124

near Colby Ranch. ........ 248

near San Fernando ........ 249-250

near Sunland. .......... 249

Tujunga Creek Basin, physiographic 

and geologic features 

of. ......... 137-140,330-331

Tustin, Irvine Ranch drainage

, canal near. ......... 227-228

u

Universal City, Los Angeles River ' 

near. ............ 243

Upland, Cucamonga Creeknear.219-220,pl.l7,B

V

Van Nuys, Los Angeles River near. . 242 

Ventura, Coyote Creek near. .... 274

Ventura River near. ....... 273

Ventura County, rainfall in .... 54,55

Ventura Free Press, quoted. .... 394

Ventura River, near Ventura .... 273

Ventura River Basin, discharge

in. ........... 272-274,297

floods in, previous . . . 389-390,352,394 

physiographic and geologic

features of ..... 340-342,346-348

rainfall, runoff, and retention

in. . . 37-39,45,73-74,77,362-363,368 

Verdugo Creek, at Glendale. .... 252-253

Verdugo Mountains, rainfall

in. ......... .25,43,68,76,80

Victorville, Mojave River near. . . 283 

Villa Park, Santiago Creek

near. ..... 105-106,225-226,pi. 5

W

Walnut Creek, near Baldwin Park . . 237 

Warm Creek, near Colton ...... 210

Warner, J. J., quoted ....... 387-388

Waterman Canyon Creek, near Arrowhead Springs. ........ 212

Weirs, flow over, computation of. . 171-172 

Whittier, San Jose Creek near ... 238 

Wolfskill Creek, near San Dimas . . 115-116

Y 

Ysidora, Santa Margarita River at . 201

o

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