FLOODS OF MAY 1978 IN

SOUTHEASTERN MONTANA AND

NORTHEASTERN WYOMING

Report prepared jointly by the U.S. Geological Survey 

and the National Oceanic and Atmospheric Administration

U.S. DEPARTMENT OF THE INTERIOR U.S. DEPARTMENT OF COMMERCE

U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1244
FLOODS OF MAY 1978 IN 

SOUTHEASTERN MONTANA AND 

NORTHEASTERN WYOMING

By CHARLES PARRETT, D. D. CARLSON, and GORDON S. CRAIG, JR.,

U.S. Geological Survey, and E. H. CHIN,

National Weather Service, National Oceanic and Atmospheric Administration

U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1244

Report prepared jointly by the U.S. Geological Survey 

and the National Oceanic and Atmospheric Administration

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON: 1984
UNITED STATES DEPARTMENT 

OF THE INTERIOR

WILLIAM P. CLARK, Secretary

UNITED STATES DEPARTMENT 

OF COMMERCE

MALCOLM BALDRIGE, Secretary

U.S. GEOLOGICAL SURVEY 

Dallas L. Peck, Director

NATIONAL OCEANIC AND 

ATMOSPHERIC ADMINISTRATION

John V. Byrne, Administrator

Library of Congress Cataloging in Publication Data 

Main entry under title:

Floods of May 1978 in southeastern Montana and northeastern Wyoming.

(Geological Survey professional paper; P1244)

Bibliography: p.

Supt. of Docs, no.: 119.16:

1. Floods Montana. 2. Floods Wyoming. I. Parrett, Charles. II. United States. Geological Survey. HI. United

States. National Oceanic and Atmospheric Administration. IV. Series.

GB1399.4.M9F46 551.48'9'097863 81-607843

AACR2

For sale by the Distribution Branch, U.S. Geological Survey, 

604 South Pickett Street, Alexandria, VA 22304
CONTENTS

Glossary ____________________________________ VI

Abstract ____________________________________ 1

Introduction __________________________________ 1

Acknowledgments ______________________________ 1

Meteorological situation __________________________ 3

Precipitation distribution _________________________ 6

General description of floods ______________________ 14

Flood magnitude ___.---_____--________________ 14

Flood frequency _______________________________ 15

Reservoirs ___________________________________ 16

Major river basins ------___----________________ 16

Yellowstone River basin ______________________ 16

Yellowstone River _______________________ 16

Pryor Creek _______________________ 17

Fly Creek _________________________ 18

Bighorn River ______________________ 18

Soap Creek, Beauvais Creek, Rotten Grass

Creek _______________________ 19

Little Bighorn River and tributaries _ _ _ _ 19

Rosebud Creek _____________________ 20

Page

Major river basins Continued

Yellowstone River basin Continued 

Yellowstone River Continued

Tongue River and tributaries ______-.___. 20

Powder River and tributaries ___________ 21

Cheyenne River basin ________________________ 22

Cheyenne River ____.-___-__________-.___ 22

Belle Fourche River __________________ 22

Platte River basin __________________________ 26

Medicine Bow River ______________________ 26

North Platte River ___-_____--_____-_____. 26

Flood damage ________________________________ 27

Sedimentation ________________________________ 28

Montana ____________--______-_____---__-. 28

Wyoming _____________-______-_____---__.- 28

Aerial photography _____________________________ 32

Flood-hydrograph data _____--_____-______---__-_ 32

Summary ___________________________________ 32

References __________________________________ 35

ILLUSTRATIONS

FIGURE 1. Map showing area affected by floods and location of flood-discharge-determination sites ____----_----_-. 2

2. Map showing climatic divisions and location of selected weather stations in Montana and Wyoming ________ 3

3. Surface weather chart of Western United States and Canada for 0500 m.s.t. May 16, 1978 ______________ 5

4. Surface weather chart of Western United States and Canada for 0500 m.s.t. May 17, 1978 ______________ 7

5. 700-millibar chart of Western United States for 1700 m.s.t. May 15, 1978 _________________________ 8

6. 500-millibar chart of Western United States for 1700 m.s-t. May 15, 1978 _______________.__-._.-_. 9

7. 700-millibar chart of Western United States for 0500 m.s.t. May 17, 1978 _______________.-___-._.- 10

8. 500-millibar chart of Western United States for 0500 m.s.t. May 17, 1978 ___________-___--__._---_ 11

9. Graph showing mass precipitation curves for four weather stations, May 16-19, 1978 ______----_---.--_ 12

10. Map showing total storm precipitation, May 16-19, 1978 __----_----------------------_------- 13

11. Graph showing comparison of May 1978 peak discharges with maximum known flood peaks __---_-.----. 15

12. Graph showing inflow, outflow, and storage contents for Bighorn Lake, Montana -------------------- 17

13. Hydrographs of discharge of the Tongue River near Decker, Mont., May 17-23, 1978 _________________ 17

14. Graph showing inflow, outflow, and storage contents of Keyhole Reservoir, Wyo., May 15-June 5, 1978 _. . .. 18

15. Hydrograph of discharge of the Yellowstone River at Miles City, Mont., May 18-24, 1978 ______________ 19

16. Photograph showing flooding along U.S. Highway 312 near Huntley, Mont., May 19, 1978 __.-____-__. 20

17. Photograph showing flooded mobile home along the east bank of the Bighorn River near Manderson, Wyo., May

	19, 1978 __._-__....._.....--....._-_...-..-.-___---__---_--__------------_ 21

18. Hydrograph of discharge of the Nowood River near Tensleep, Wyo., May 16-21, 1978 _________________ 22

19. Photograph showing flooded farmsteads on the left bank of the Bighorn River, 2 miles northeast of Hardin, Mont.,

	May 19, 1978 __________________________.__________________--__._---__-_----- 23

20. Hydrograph of discharge of the Bighorn River at Bighorn, Mont., May 17-22, 1978 ___________________ 23

21. Photograph showing flooding at Lodge Grass, Mont., May 19, 1978 ----------------------------- 24

in
IV CONTENTS

Page

FIGURE 22. Photograph showing flooding of the Little Bighorn River in the town of Crow Agency, Mont., at the Interstate Highway 1-94 interchange, May 19, 1978 ..........................-..-----.-------.----- 25

23-25. Hydrographs of discharge of:

23. Little Bighorn River, May 17-22, 1978 _.._........._.._........--..-.._-----..--.- 26

24. Goose Creek below Sheridan, Wyo., May 17-22, 1978 ......._....._.._.._.._..-....-_.. 26

25. Little Powder River above Dry Creek near Weston, Wyo., May 17-22, 1978 _.._.._.._..._.... 26

26. Photograph showing flooding of Lance Creek near Bright, Wyo., May 19, 1978 .......__.__-__.._... 27

27. Hydrograph of discharge of Lance Creek near Riverview, Wyo., May 17-22, 1978 ._....._..__.__.__.. 28

28. Photograph showing bridge on the Cheyenne River near Riverview, Wyo., May 25, 1978 ---__------.--- 29

29. Photograph showing flood damage along the Belle Fourche River below Rattlesnake Creek near Piney, Wyo., May

19, 1978 ....__...__.._......._.._.._......_.._..-..-..-.....-...-..-.-...- 30

30. Hydrograph of discharge of Donkey Creek near Moorcroft, Wyo., May 17-22, 1978 ____.--.--------.-- 31

31. Hydrograph of discharge of the Medicine Bow River above Seminoe Reservoir near Hanna, Wyo., May 17-22,1978 . 31

32. Photograph showing headcutting near the mouth of Black Thunder Creek, near Hampshire, Wyo., May 19, 1978 . 31

33. Suspended-sediment transport curve of the Bighorn River near Kane, Wyo., October 1969 to September 1978 . 32

34. Map showing location of flight lines along streams where aerial photographs were obtained at or near crest of flood,

May 19-20, 1978 .....__...._..._._......._.._....__....._..-.._.....-.--.--.. 34

TABLES

TABLE 1. Precipitation amounts at selected National Weather Service stations in the flooded area ......

2. Average precipitation for May 1978 compared with climatic normals for selected climatic divisions

3. Summary of flood stages and discharges _______________________________________

4. Summary of stage and contents for Bighorn Lake near St. Xavier, Mont. ________________

5. Summary of flood damage, in dollars _________________________________________

6. Daily suspended-sediment discharge for the Powder River in Montana __________________

7. Sediment data ________________________________________________________

8. Aerial photography of the May 1978 flood in Montana ______________________________

9. Gage heights and discharges at selected gaging stations _-______-____-_______-___-._

Page

4

4

39

16

28

32

52

33

59
CONVERSION FACTORS

CONVERSION FROM INCH-POUND SYSTEM TO SI UNITS

Inch-pound

inch (in.)

foot (ft)

mile (mi) 

square mile (mi^)

acre-foot (acre-ft)

mile per hour (mi/h)

cubic foot per second 

(ft 3 /s)

cubic foot per second 

per square mile 

[(ft3/s )mi2]

to SI

= 25.4 mm

0.3048 m

1.6093 km 

2.5900 km2

1233 m3

« 0.4470 cm/s

0.02832 m3 /s

0.01094 (m3 /s)km2

ton per day (ton/d) = 0.9072 Mg/d

SI to

Length

millimeter (mm) =

meter (m) 

kilometer (km) = 

Area

square kilometer (km2 ) =

Volume

cubic meter (m3 ) = 

Velocity

kilometer per hour (km/h) =

Discharge 

cubic meter per second = 

(m3 /s)

cubic meter per second 

per square kilometer = 

((m 3/s)km2 ]

megagram per day (Mg/d) = 

Pressure

[The National Weather Service uses millibar as customary unit for atmospheric

inch of mercury at 

32°F

33.8639 mb millibar (mb) = 

Inch-pound

0.03937 in.

3.2808 ft

0.6214 mi 

0.3861 mi 2

0.00081 acre-ft

2.237 mi/h

35.3147 ft 3/s

91.40768 

(ft3/s)/mi2

1.102 ton/d 

pressure]

0.02953 in. 

of mercury
VI GLOSSARY

GLOSSARY

Acre-foot (acre-ft). The volume of water required to cover 1 acre to 

a depth of 1 ft. It equals 43,560 ft3 (cubic feet), 325,851 gal 

(gallons), or 1,233 m3 (cubic meters).

Contents. The volume of water in a reservoir or lake. Content is 

computed on the basis of a level pool or reservoir backwater 

profile and does not include bank storage.

Convection cloud. A cloud which owes its vertical development, and 

possibly its origin, to convection.

Convective cell. An organized, convective, fluid motion characterized 

by the presence of distinct upward motion in the center of the 

cell and sinking or downward flow in the outer regions.

Cubic foot per second (ft3/s). A rate of discharge. One cubic foot per 

second is equal to the discharge of a stream of rectangular 

cross section 1 ft wide and 1 ft deep, flowing at an average velocity of 1 ft/s. It equals 28.32 L/s (liters per second) or 0.02832 

m3/s (cubic meter per second).

Cubic foot per second per square mile, (ft3/s)/mi2. The average 

number of cubic feet of water flowing per second from each 

square mile of area drained by a stream, assuming that the 

runoff is distributed uniformly in time and area. One ft3/s per 

square mile is equivalent to 0.0733 m3/s per square kilometer.

Dew point (or dew-point temperature). The temperature to which a 

given parcel of air must be cooled at constant pressure and 

constant water-vapor content for saturation to occur.

Drainage area of a stream at a specific location. An area, measured on a horizontal plane, bounded by topographic divides. 

Drainage area is given in square miles. One m2 is equivalent 

to 2.590 km2 (square kilometers).

Exceedance probability. The probability, expressed as a percentage, 

that a given magnitude of flood discharge will be exceeded during any given year. The reciprocal of exceedance probability is 

recurrence interval. Thus a flood magnitude with an exceedance probability of 1 percent has a recurrence interval of 100 

years.

Flood. Any streamflow that overtops natural or artificial banks of a 

stream and inundates land not usually underwater.

Front. The interface or transition zone between two airmasses of different densities.

Gaging station. A particular site on a stream, canal, lake, or reservoir where systematic observations of gage height or discharge 

are made.

K Index. A measure of the airmass moisture content and static stability given by:

where T is temperature and TA is dewpoint, in degrees

Celsius, and the subscripts denote pressure level in millibars.

The larger the K index of the airmass, the more unstable it is. 

Low. Center of low barometric pressure. 

National Geodetic Vertical Datum of 1929 (NGVD of 1929). A

geodetic datum derived from a general adjustment of the firstorder level nets of both the United States and Canada, formerly called "mean sea level." 

Millibar (mb). A unit of pressure equal to 1,000 dynes per square

centimeter. 

Peak discharge. The maximum instantaneous discharge attained during a flood.

Peak stage. The highest instantaneous stage attained during a flood. 

Precipitable water. The total atmospheric water vapor contained in

a vertical column of unit cross-sectional area extending from

the surface up to a specified pressure level, usually 500 mb. 

Recurrence interval. As applied to hydrologic events, the average

number of years within which a given hydrologic event will be

exceeded once. 

Suspended sediment. The sediment that at any given time is maintained in suspension by the upward components of turbulent

currents or that exists in suspension as a colloid. 

Suspended-sediment discharge. The rate at which dry weight of sediment passes a section of a stream, or the quantity of sediment, as measured by dry weight or by volume, that passes a

section in a given time. 

Temperature. Air temperature is expressed in degrees Fahrenheit.

Water and dew-point temperatures are expressed in degrees

Celsius. Temperature in degrees Celsius is equivalent to 5/9

(°F-32). 

Time of day is expressed in 24-hour time. For example, 12:30 a.m.

is 0030 hours; 1:00 p.m. is 1300 hours. 

Vorticity. A vector measure of local rotation in a fluid flow, defined

mathematically as the curl of the velocity vector:

q = V XV 

where q is the vorticity, V the del-operator, and V the velocity.
FLOODS OF MAY 1978 IN SOUTHEASTERN MONTANA AND

NORTHEASTERN WYOMING

By CHARLES PARRETT, D. D. CARLSON, and GORDON S. CRAIG, Jr., U.S. Geological Survey, 

and E. H. CHIN, National Weather Service, National Oceanic and Atmospheric Administration

ABSTRACT

Intense rain and some snow fell on previously saturated ground in 

southeastern Montana and northeastern Wyoming during May 16-19, 

1978. The 7.60 inches that fell within a 72-hour period, measured at 

Lame Deer, Montana, set a record for the month of May in that region.

Widespread flooding occurred in the drainages of the Yellowstone 

River and its tributaries as well as the Belle Fourche, Cheyenne, and 

North Platte Rivers. The previous maximum flood of record was exceeded at 48 gaged sites, and the 1-percent-chance flood was equaled 

or exceeded at 24 sites. Flood damage was extensive, exceeding $33 

million. Nineteen counties in the two States were declared major disaster areas.

Mean daily suspended-sediment discharges exceeded previously recorded maximum mean daily values at four sites on the Powder 

River. The maximum daily suspended-sediment discharge of 

2,810,000 tons occurred on May 20 at the Powder River site near Arvada, Wyoming.

INTRODUCTION

Widespread and steady rain mixed with some snow 

at higher elevations fell during May 16-19, 1978, over 

southeastern Montana and northeastern Wyoming. 

Rainfall was greatest in the upper Tongue River drainage, where precipitation exceeded 7 in. The ground was 

saturated from earlier storms, and streams were generally flowing bankfull from snowmelt runoff. Subsequent 

flooding occurred along the Yellowstone River and its 

major tributaries the Bighorn, Tongue, and Powder 

Rivers as well as the Belle Fourche, Cheyenne, and 

North Platte Rivers. Flood peaks at about one-third of 

the streamflow-gaging stations in the area exceeded the 

maximum flows previously known. Record values for 

suspended-sediment discharge were established at 

some sites along the Powder and Bighorn Rivers.

Flood damage to roads, bridges, cropland, and buildings was extensive. Nineteen counties in Montana and

Wyoming were declared major disaster areas by the 

Federal Government. The area affected by flooding is 

shown in figure 1.

This report documents the meteorological setting and 

hydrologic conditions of the flooding. Included are 

analyses of the distribution of storm rainfall and the 

magnitude and exceedance probability of the flood-peak 

discharges. A specific account is given of flood conditions for each of the affected drainage basins. The effect of reservoir storage on discharge also is assessed. 

Flood-stage and discharge data with corresponding exceedance probabilities and significant sediment-discharge data are also presented.

ACKNOWLEDGMENTS

Many of the meteorological analyses were produced 

by the National Meteorological Center of the National 

Weather Service. Other analyses are based on data collected and observations made by National Weather Service field offices. Flood data in this report were collected as part of cooperative programs among the U.S. 

Geological Survey, the States of Montana and Wyoming, and agencies of the Federal Government. Information on reservoir operation and flood photographs were 

provided by the U.S. Bureau of Reclamation. Flooddamage data were obtained from the Federal Disaster 

Assistance Administration, the U.S. Agricultural 

Stabilization and Conservation Service, and the Wyoming Disaster and Civil Defense Agency. Selected photographs were provided by the Montana Department of 

Highways. The assistance provided by these agencies is 

gratefully acknowledged.
MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

EXPLANATION

A7 Site of flood-discharge determination 

Number refers to Table 3

FIGURE 1. Area affected by floods and location of flood-discharge-determination sites.
METEOROLOGICAL SITUATION

METEOROLOGICAL SITUATION

Greater-than-normal precipitation during late April 

and early May occurred both in south-central and 

southeastern Montana and in central and northeastern 

Wyoming. Two antecedent storms occurred in the 3 

weeks before the storm began on May 16. The first, on 

April 26-30, left the soil saturated. The second occurred

during May 2-8. During May 4-7 a snowstorm deposited 

15 to 32 in. of wet, heavy snow in much of central and 

eastern Wyoming. This period was followed by a warming trend that culminated on May 15 in maximum temperatures of 95°F at Broadus, Mont., 90°F at Lame 

Deer, Mont., 87°F at Sheridan Wyo., 86°F at Casper, 

Wyo., and 94°F at Redbird, Wyo. (fig. 2). Melting snow 

caused mountain streams to flow at bankfull stages

NORTH CENTRAL

NORTHEASTERN

SOUTHEASTERN

YELLOWSTONE

2NW,DRA.NAGEo

CHEYENNE 1 

I SNAKE AND

DRAINAGE

GREEN

AND

BEAR

DRAINAGE

Wheatland 4 N|tO

-il

LU

PLATTE

UPPER PLATTE

EXPLANATION

CENTRAL Climatic division name 

and boundary

WEATHER STATION

^ Complete weather station

<^ Precipitation, temperature, 

and evaporation

^ Precipitation and temperature 

^ Precipitation

0 20 40 MILES

0 20 40 60 KILOMETERS

COLORADO

FIGURE 2. Climatic divisions and location of selected weather stations in Montana and Wyoming.
MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

prior to the onset of the May 16-19 storm. The following precipitation amounts were recorded at selected 

stations during the 3 weeks before May 15. Snow depth 

has been converted to equivalent water depth.

Gillette 18 SW, WyoSheridan Airport, WyoAshland Ranger Station, Mont 

Yellowtail Dam, Mont 

5.30 in. 

4.09 in. 

3.70 in. 

6.96 in.

By comparison, the normal monthly precipitation at 

Sheridan Airport, Wyo., for May is 2.45 in.

In addition to precipitation during May 16-19, much 

precipitation also fell during 10 other days of the 

month. Precipitation amounts at some sample stations 

compared with climatological averages are given in 

table 1. The much-greater-than-normal precipitation 

was not limited to individual stations but extended 

throughout southeastern Montana and northeastern 

Wyoming. Average precipitation for May 1978 in climatic divisions in this region is listed in table 2. The demarcation of climatic divisions as used by the National 

Climatic Center of the National Oceanic and Atmospheric Administration is shown in figure 2.

On May 14 at 0500 m.s.t., 2 days before the storm, 

a deep upper trough existed off the Pacific coast from 

850 mb to above 500 mb. At the surface the weather 

system consisted of a complex series of Lows and 

fronts. The primary weather feature was a Low about 

400 mi west of the British Columbia-Washington coast. 

The associated cold front, extending eastward from the 

center, was about 50 mi from the Washington and OreTABLE 1. Precipitation amounts at selected National Weather Service stations

Year* of

Precipitation (inches)

Date* of

Station

Montana:

Decker 4 NNE

Hardin 2 S

Pryor

Wyoli 2 SW

Yellowtail Dam

Biddle

Birney 2 SW

Broadus

.Colstrip

Lame Deer

Wyoming:

Gillette 2 E

Gillette 18 SW

Echeta 2 NW

Sheridan Airport

Casper 2 E

Dull Center 1 SB

Wheat land 4 H

Themopoli* 2

Cody

record

19

37

23

47

16

27

24

46

SO

45

58

23

15

33

59

49

65

14

68

Long-tern 

May average

__

1.70

 

2.45

___

___

-__

2.23

2.47

2.59

2.50

 

_-_

2.45

2.41

2.28

2.53

1.90

1.51

May 1978

7.12

6.47

8.46

8.65

9.28

7.40

7.71

7.10

9^27

12.44

11.03

10.27

11.26

6.80

7.18

6.93

3.86

10.31

4.73

Storm 

totals

4.40

4.19

5.79

5.11

5.33

2.66

4.48

3.41

4.80

7.60

5.06

5.40

4.65

3.78

3.58

3.57

1.78

5.17

3.36

occurrence 

(M«y)

16-13

17-19

17-19

17-19

16-19

17-19

17-19

16-19

17-19

17-19

17-19

16-19

16-19

16-19

16-18

17-19

17-18

17-19

17-19

TABLE 2. Average precipitation for May 1978 compared 

with climatic normals for selected climatic divisions

Precipitation (inches)

Division

Average, 

May 1978 Normal Departure

Montana:

Northeastern 

South Central 

Southeastern

Wyoming:

5.29

6.43

6.91

1.74

2.40

2.09

+3.55 

+4.03 

+4.82

Big Horn

Powder, Little Missouri,

and Tongue drainage

Belle Fourche

drainage

Cheyenne and

Niobrara drainage

Wind River

5.29

8.02

8.37

5.27

4.55

1.53

2.34

2.68

2.51

1.98

+3.76

+5.78

+5.69

+2.76

+2.57

gon coast. A second Low was located in eastern 

Washington and Oregon, and a third Low was in central Alberta province, Canada. Precipitation was widespread over southern British Columbia, Washington, 

and northern Oregon west of the Cascade Range.

Over Montana and Wyoming the winds aloft were 

westerly and southwesterly, and were associated with 

the trough off the Pacific coast and a ridge that extended from central New Mexico north-northeastward 

to central North Dakota. At the surface, winds were 

light with a generally southerly flow east of the Rocky 

Mountains, bringing moisture northward from the Gulf 

of Mexico. Average surface dew point over the Montana-Wyoming region on the leeward side of the Rocky 

Mountains was about 45°F, compared with the monthly 

mean for May of 35°F. The average precipitable water 

in this region, however, was close to the monthly mean 

of 0.35 in. estimated from Lott (1976).

The weather system moved eastward, and by 0500 

m.s.t. on May 15, the upper trough and the primary 

surface Low were both located along the Pacific coast. 

The associated cold front, ahead of the surface Low, 

now extended from the British Columbia-Alberta border southward and then southwestward through central 

Idaho and northwestern Nevada and exited the coast in 

the vicinity of San Francisco Bay. By 0500 m.s.t. May 

16 this cold front had reached eastern Montana and extended through southeastern Wyoming, northwestern 

Colorado, and southeastern Utah (fig. 3). Then the 

movement of the northern part of this front slowed and
145° 135'

METEOROLOGICAL SITUATION

125° 115° 105° 95° 85°

35'

25'

Cold front 

Warm front 

Stationary front

EXPLANATION 

^^ 04"~ Line of equal pressure (isobar) Interval

H

4 millibars. Number is last two digits 

of pressure: 04->1004

High 

Low

FIGURE 3. Surface weather chart of Western United States and Canada for 0500 m.s.t. May 16, 1978.
6 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

the front became stationary over eastern Montana, 

Wyoming, and the Dakotas. Meanwhile, an incipient 

closed Low appeared in Colorado. This Low became associated with the southern part of the cold front, and 

both became nearly stationary. By 0500 m.s.t. May 17, 

the entire cold front was oriented nearly north-south 

(fig. 4).

Before the storm began, the Montana-Wyoming region had been located under 700-mb and 500-mb troughto-ridge flow patterns (figs. 5 and 6). Usually, low-level 

horizontal convergence, high-level horizontal divergence, and upward vertical motion exist between 

trough and downwind ridge, and are conditions favorable to subsequent storm development provided that adequate moisture supply is available.

Persistent southerly flow in the lower levels brought 

moist air that had originated over the Gulf of Mexico. 

Preeipitable water over the region increased steadily 

after May 15, reaching an average of 0.70 in. by 0500 

m.s.t. May 17, which was 200 percent of the mean 

monthly precipitable water for May of 0.35 in. estimated over the same area. For comparison, the 

maximum precipitable water that has been observed 

during May 16-31 over this same region is 1.00 in. 

(Riedel and Ho, 1979). The average surface dew-point 

temperature estimated for the region was 58°F at 1700 

m.s.t. May 16, when rain began over northeastern 

Wyoming. By comparison, the climatic mean surface 

dew-point temperature over the region for May is 35°F 

(U.S. Environmental Science Services Administration, 

1968). Aloft over the region, dew-point depression during the storm was only 0° to 1°C at 700 mb and 2°C at 

500 mb. The mean relative humidity throughout the 

lower layers of the atmosphere, averaged over the 

whole region, was 60 percent during the evening of 

May 16, increasing to more than 90 percent by the evening of May 18. All these conditions indicated that an 

abundant moisture supply was available.

The 1700 m.s.t. May 16 analysis of 500-mb heights 

and vorticity showed that the absolute vorticity over 

the region was about 10 x 10"5 per second. It increased 

to 16 x 10'5 per second in a closed center of maximum 

absolute vorticity by 0500 m.s.t. May 18. Strong cyclonic circulation, low- level convergence, and rising motion generally occur concurrently with the vorticity 

maximum. Areas of vertical velocity exceeding 2.2 cm/s 

(centimeters per second) first appeared over eastern 

Wyoming and then moved over eastern Montana. The 

vorticity maximum progressed eastward toward the 

Dakotas and left the region by 0500 m.s.t. May 19.

The frontal system extending from the Low in southern Wyoming and northern Colorado moved slowly 

eastward. By morning of May 19 the Low and the associated frontal system were over the central Dakotas.

The 700-mb Low also moved to the east of the region, 

and northerly flow began to replace the persistent 

southerly flow of the previous 3 days. This change in 

the upper airflow pattern also put the region under a 

500-mb ridge-to-trough pattern. With relatively dry 

and cool northerly flow prevailing and with a ridge approaching from the west, the sky cleared and the storm 

ended. By 1700 m.s.t. May 19, a high-pressure cell was 

established over north-central Wyoming.

PRECIPITATION DISTRIBUTION

Intense rain began in northeastern Wyoming early in 

the evening of May 16. The southerly flow at 500 mb 

forced the precipitation area northward, parallel to the 

front. Intense rain began in southeastern Montana later 

in the same evening. Except for occasional brief intermissions, the precipitation continued from the evening 

of May 16 until the morning of May 19. Precipitation 

the evening of May 16 was in the form of rain in all sectors, but by morning of May 17 snow was falling at 

some locations with elevations as low as 5,500 ft. Most 

of the snow melted as it touched the ground; however, 

deep accumulations occurred in some areas with elevations above 6,000 ft. Weather station Gas Hills 4E in 

Wyoming, at an elevation of 7,000 ft, reported a 

maximum accumulation of 25 in. of snow on the ground 

on May 18. The presence of the quasistationary synoptic scale frontal boundary parallel to the upper-air flow 

during May 16 and 17 (figs. 4, 7, 8) helped to focus the 

precipitation over this region for about 60 hours.

The precipitation was associated with a slowly moving quasistationary frontal system. Moisture supply in 

the storm area was abundant. However, the combined 

thermal and moisture vertical structure of the atmosphere was only moderately unstable. The estimated K 

index for the region did not exceed 28 for the duration 

of the storm, denoting moderate thunderstorm potential and little likelihood of severe thunderstorms. Precipitation was produced mainly by imbedded convective 

cells associated with the cold front. Most of the precipitation was in the sector behind the cold front.

Selected mass precipitation curves for four representative stations are shown in figure 9. Total storm precipitation is shown in figure 10. The drainages receiving 

substantial precipitation were those of the Big Horn 

(including the Little Big Horn), Tongue, Powder, Belle 

Fourche, and Cheyenne Rivers.

The maximum point rainfall was 7.60 in., recorded at 

Lame Deer, Mont., within the 72 hours ending 1600 

m.s.t. May 19. This amount far exceeded the corresponding 100-year 72-hour precipitation of 4.40 in. determined with the procedures developed by Miller (1964)
140°

PRECIPITATION DISTRIBUTION

130° 120° 110° 100° 90°

35

25'

Cold front

Warm front

Stationary front

EXPLANATION 

^^ 04 Line of equal pressure (isobar) Interval

H

4 millibars. Number is last two digits 

of pressure: 04-^1004

Low

FIGURE 4. Surface weather chart of Western United States and Canada for 0500 m.s.t. May 17, 1978.
30°

MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO. 

130° 120° 110° 100° 90°

2970X3000 

. . ^ ^ i 3030 ^ "v_- . 306 ^/ 

3000 Line of equal height Interval 

30 meters

EXPLANATION

 +5 Line of equal temperature 

(isotherm) Interval 5° 

Celsius

FIGURE 5. 700-millibar chart of Western United States for 1700 m.s.t. May 15, 1978.
135

30'

125'

PRECIPITATION DISTRIBUTION

115° 105° 95° 85°

EXPLANATION

5700-

L

Line of equal height Interval 

60 meters

Low

 -10 Line of equal temperature 

(isotherm) Interval 5° 

Celsius

FIGURE 6. 500-millibar chart of Western United States for 1700 m.s.t. May 15,1978.
10 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO 

130° 120° 110° 100° 90° 80°

 3090'

H 

L

Line of equal height Interval 

30 meters 

High

Low

EXPLANATION

 +5 Line of equal temperature 

(isotherm) Interval 5° 

Celsius

FIGURE 7. 700-millibar chart of Western United States for 0500 m.s.t. May 17, 1978.
140° 130°

PRECIPITATION DISTRIBUTION

120° 110° 100°

11

90°

30

.5700 

H

EXPLANATION

Line of equal height Interval « 

60 meters 

High

Low

Line of equal temperature 

(isotherm) Interval 5° 

Celsius

FIGURE 8. 500-millibar chart of Western United States for 0500 m.s.t. May 17, 1978.
§»

M 

O

ii'

JO 

OS

i >

00

O

ro 

4^ 

o 

o

CUMULATIVE PRECIPITATION, IN INCHES

N> CO 4*.

3 ro < o

-» o

O)

< ^

< o

_» o

< o

_» o

00

0) M 

< O

CD

ro

CO i

H o "~ c

DO 

C/5
112'

PRECIPITATION DISTRIBUTION

110° 108°

13

47 C

46C

45C

44°

43C

0 20 40 60 80 100 MILES

h-H r^n '

0 20 40 60 80 100 KILOMETERS

42°

EXPLANATION

Line of equal precipitation (isohyet) 

Interval 1 inch

FIGURE 10. Total storm precipitation, May 16-19, 1978.
14 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

and 1- and 24-hour values from Miller and others 

(1973).

Considering the scarcity of actual rainfall observations in this region, the maximum point value probably 

was not recorded. Therefore, the greatest observed 

rainfall is assumed to represent the average depth over 

an appreciable area, rather than the maximum point 

rainfall. A common assumption is that the maximum 

station rainfall represents an average depth over 10 

mi2. In practice, precipitation amounts for past significant storms were tabulated for durations of 6, 12, 18, 

24, 48, and 72 hours. The May 16-19, 1978, storm actually lasted about 60 hours. Therefore, the maximum 72- 

hour precipitation over 10 mi2 was considered conservatively to be 7.60 in. For comparison, 5.50 in. is the 

greatest observed 10-mi2 72-hour precipitation for the 

month of May in a section enclosing Lame Deer, Mont., 

bounded by latitude 44°N. and 49°N., and by longitude 

105°W. and 110°W. (United States-Canada boundary).

The precipitation for the May 16-19, 1978, storm established a record for May. However, when all months 

are considered, the rank of this storm is third greatest. 

The historical file used as a basis for comparison consists of extreme areal storm-rainfall depths that have 

been determined by the U.S. Army, Corps of Engineers, and other Government agency field offices 

(U.S. Army, Corps of Engineers, updated annually 

since 1945). The stratification by duration and geographical area used in this comparison is from the National Weather Service, Hydrometeorological Branch 

(1979).

GENERAL DESCRIPTION OF FLOODS

The area affected by the May 1978 floods in Montana 

and Wyoming is shown in figure 1. Major drainages in 

Montana where flooding occurred include the Yellowstone River and its major tributaries the Bighorn 

River, Tongue River, and Powder River. Drainages affected in Wyoming include these three tributaries of 

the Yellowstone River as well as the Belle Fourche 

River, Cheyenne River, and North Platte River. Peaks 

in the North Platte River drainage generally resulted 

from the first rain on May 16 or the early morning of 

May 17, whereas peaks in the more northerly basins 

were caused by the later rains.

Streams throughout the area generally were flowing 

near or at bankfull stage before the May 16-19 precipitation because of greater-than-average precipitation 

and snowmelt runoff during early May. The high antecedent flows, generally saturated ground conditions, 

and stockwater reservoirs already at or near capacity

contributed to the record and near-record floodflows 

that occurred.

The precipitation at the higher elevations was snowfall (Burgess Junction, in the Big Horn Mountains in 

Wyoming, reported 27 in.), which delayed runoff of 

some of the mountain streams. These streams peaked 

several days later when warm temperatures melted the 

snow. Flooding would have been much more severe if 

all the precipitation had been rainfall.

Peak discharges and peak stages were determined at 

164 selected sites. At 30 of the sites, peak discharges 

were determined by indirect methods after the floodwaters receded. The remaining sites were either active 

or discontinued streamflow-gaging stations where 

stage-discharge relationships already were available. In 

all instances, trained personnel from the U.S. Geological Survey were dispatched to collect stage data, measure streamflow where possible, and obtain onsite survey data required for the indirect discharge measurements. Sites where data were collected and peak discharges determined are shown in figure 1.

The peak discharges and stages are given in table 3 

(at end of report). The numbers in the first column of 

table 3 correspond to the site numbers shown in figure 

1. For convenience, site numbers are used throughout 

this report. The permanent station number is the 

number of the streamflow-gaging-station used in the 

annual data reports of the Geological Survey. The sites 

are numbered consecutively in downstream order. Sites 

on tributaries are listed between sites on the main 

stream in the order in which those tributaries enter the 

main stream. Sites on tributaries entering upstream 

from all main-stream sites are listed before the first 

main-stream site.

FLOOD MAGNITUDE

Peak discharges at about one-third of the streamflowgaging stations were the largest since the stations were 

established. A comparison of May 1978 flood discharges 

with the greatest known flood discharges in the area 

can be made from figure 11, which relates discharge, in 

cubic feet per second per square mile, to corresponding 

drainage area. Enveloping curve A, defined by the 

largest known flood discharges, and enveloping curve 

B, defined by the May 1978 flood discharges, indicate 

that the May 1978 peak flows generally were about 50 

percent less than the maximum known peak flows for 

drainage areas greater than 100 mi2. For drainages 

smaller than 100 mi2, the May 1978 peak discharges 

were about 50-80 percent less than the maximum 

known peak discharges. The gradual flattening of curve 

B for drainage areas less than 100 mi2 indicates that
FLOOD FREQUENCY 15

a

CO

2000

1000

n i i i i ixir 

87

~ CURVE B

100

10

0.'

87

147

10

73

161

74 -CURVE A

.40 159

.48 2> \151

. 26 %r

128* 30* 7

\

\

 : «v

. * «J. ^51 ' 

 * X * c

' / " { '" " :'".':.'* ::::136"^> \

EXPLANATION 

; X Maximum discharge known 

" Maximum discharge during May 1978 

3 Number corresponds to flood

determination site in Table 3 

Curve A: Enveloping curve through maximum

discharges known

Curve B: Enveloping curve through maximum 

discharges during flood of May 1978 

I I I I I I ill i i I i I I I II

0.1 1 10 100 1000 

DRAINAGE AREA, IN SQUARE MILES

10,000 100,000

FIGURE 11. Comparison of May 1978 peak discharges with maximum known flood peaks.

smaller streams in the area did not flood appreciably, 

and that record flooding on the larger streams was not 

the result of peak-flow contributions from some small 

tributaries. Rather, all tributaries appeared to be contributing to a gradual buildup of flow that culminated in 

large discharges on the larger streams.

FLOOD FREQUENCY

Information on the magnitude and frequency of flooding is necessary for the adequate design of flood-plain 

structures and for making management decisions about 

flood-plain land use. In this report the frequency of 

flooding is expressed as the percentage chance of exceeding a specified flood magnitude during any 1-year 

period. Thus, a 2-percent-chance flood has 2 chances in

100 of being exceeded during any 1-year period. The occurrence of floods is assumed to be random in time; no 

schedule or regularity of occurrence is implied. The occurrence of a 2-percent-chance flood is no guarantee, 

therefore, that a similar-size flood will not occur next 

week or next year.

For time periods longer than 1 year, the risks of experiencing large floods increase in a nonadditive fashion. For example r the risk of exceeding a 1-percentchance flood one or more times during a 30-year period 

is 25 percent and during a 70-year period is 50 percent.

The frequency of flooding was derived from a statistical analysis of annual peak flows at the gaging stations 

in the flood area. The method generally used to determine the flood-flow frequencies is described by the U.S. 

Water Resources Council (1977). At gaging sites in 

Montana having short flood records (less than 10 

years), flood frequencies were determined from a re-
16 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

gional flood-frequency study by the U.S. Geological 

Survey (Johnson and Omang, 1975). Flood-frequency 

information was not developed for sites on streams 

materially affected by regulation or diversion, or for 

Wyoming stream sites where the record length was less 

than 10 years.

RESERVOIRS

In Montana, the only major storage reservoirs located in the flood area are Bighorn Lake, which is 

formed behind Yellowtail Dam on the Bighorn River, 

and the Tongue River Reservoir on the Tongue River.

On the Bighorn River, peak flows and stages were 

reduced substantially as a result of reservoir flood-control operations. Thus, although the peak inflow to 

Bighorn Lake was 27,000 ft3/s on May 18, the release 

to the river downstream from the dam was held to 

1,220 ft3/s on May 20-21 (U.S. Bureau of Reclamation, 

1979). The U.S. Bureau of Reclamation also estimated 

that peak discharge of the Bighorn River at Bighorn, 

Mont, (site 39), was reduced by about 25,000 ft3/s; for 

the Yellowstone River at Miles City (site 72) the peak 

discharge was reduced about 22,000 ft3/s and the peak 

stage was reduced 2 ft as a result of operation of 

Bighorn Lake. The reduction in stage at the Bighorn 

River site (site 39) could not be determined because of 

unknown backwater effects at higher flows. A summary 

of stage and contents for Bighorn Lake during MayJune 1978 is presented in table 4. Curves of reservoir 

inflow, outflow, and storage contents through early 

June are shown in figure 12.

Although the Tongue River Reservoir is not operated 

as a flood-control structure, reservoir storage significantly reduced the peak discharge of the Tongue River, 

from 17,500 ft3/s at the Montana-Wyoming State line 

(site 53) to 10,800 ft3/s at Tongue River Dam (site 56). 

Nevertheless, high flows at the dam seriously damaged 

the reservoir outlet structure and spillway. Although 

daily reservoir stages are not available, a composite hydrograph showing discharge at State line and at Tongue 

River Dam is shown in figure 13.

In Wyoming, the only major reservoir affected by 

large-scale flooding was Keyhole Reservoir on the Belle 

Fourche River. This reservoir spilled for the first time 

in its 26-year history and reached a record storage level 

on May 22, 1978. The peak outflow (combined spill and 

release) recorded on May 23 also was a new maximum 

of record. As is indicated by the curves of inflow, outflow, and storage contents in figure 14, the peak discharge of the Belle Fourche River was reduced by 

about 14,000 ft3/s as a result of the storage in Keyhole 

Reservoir. The reduction in stage was not determined.

TABLE 4. Summary of stage and contents for Bighorn Lake 

near St. Xavier, Mont.

[Station 06286400; time 2400 hours, m.s.t. Maximum reservoir inflow, 27,000 

cubic feet per second, May 18. Maximum reservoir contents, 1,236,700 acrefeet, July 13. Records furnished by U.S. Bureau of Reclamation]

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

Elevation

above NGVD

of 1929 

(feet)

3,608.45

3,609.54

3,610.41

3,611.08

3,611.84

3,612.94

3,613.90

3,614.76

3,615.34

3,615.84

3,616.35

3,616.74

3,617.23

3,617.73

3,618.10

3,618.73

3,619.88

3,624.17

3,628.93

3,632.79

3,634.54

3,635.81

3,636.92

3,637.92

3,638.75

3,639.40

3,639.71

3,639.85

3,640.00

3,640.09

3.640.11

May 1978

Concents 

(acre-feet)

828,500

836,000

841.500

845,400

850,000

857,500

865,200

873,400

878,700

883,100

887,400

890,600

894,400

898,200

901,000

905,600

914,000

949,900

993,300

1,032,300

1,051,300

1,065,500

1,078,400

1,090,300

1,100,400

1,108,500

1,112,400

1,114,100

1,116,000

1,117,200

1,117,400

Change in

storage 

(acre-feet)

_____

+ 7,500

+ 5,500

+ 3,900

+ 4,600

+ 7,500

+ 7,700

+ 8,200

+ 5,300

+ 4,400

+ 4,300

+ 3,200

+ 3,800

+ 3,800

+ 2,800

+ 4,600

+ 8.400

+35,900

+43,400

+39,000

+19,000

+14,200

+12,900

+11,900

+10,100

+ 8,100

+ 3,900

+ 1,700

+ 1,900

+ 1,200

+ 200

Elevation

above NGVD

of 1929 

(feet)

3,640.07

3,639.82

3,639.55

3,639.20

3.638.95

3,638.41

3.638.30

3,638.27

3,638.20

3,638.52

3,638.98

3,639.07

3.639.05

3,639.04

3,639.56

3,640.27

3,640.74

3,641.12

3,641.27

3,641.43

3,641.50

3,641.50

3,641.70

3,641.86

3,642.10

3.642.20

3,642.15

3,642.19

3,642.55

3,643.11

 

June 1978

Contents

Contents 

(acre-feet)

1.116,900

1,113,700

1,110,400

1,105,000

1,102,800

1,096,200

1,094.900

1,094.500

1,093,700

1,097.600

1,103,200

1,104.300

1,104,100

1.104,000

1,110,500

1,119,500

1,125,600

1,130,500

1,132,500

1,134,600

1,135,500

1,135,500

1,138,200

1,140.300

1.143.500

1,144.900

1.144,200

1,144,700

1,149,600

1,157,200

 

Change in

storage 

(acre-feet)

- 500

-3,200

-3,300

-5,400

-2,200

-6,600

-1,300

- 400

- 800

+3,900

+5,600

+1,100

- 200

- 100

+6,500

+9.000

+6,100

+4.900

+2.000

+2.100

+ 900

0

+2.700

+2,100

+3,200

+1,400

- 700

+ 500

+4,900

+7,600

 

MAJOR RIVER BASINS

YELLOWSTONE RIVER BASIN

Record flooding occurred on several streams tributary to the Yellowstone River. Of the small tributaries, 

flooding was severe on Pryor Creek and Fly Creek 

near Billings, Mont. The Bighorn River, a major tributary, flooded extensively as did its major tributaries. 

Flooding was minor on the small Yellowstone River 

tributaries downstream from the mouth of the Bighorn 

River. Record flooding occurred on the Tongue River 

and its tributaries upstream from Tongue River Reservoir, but little overbank flooding occurred downstream 

from the Tongue River Reservoir. Significant flooding 

also occurred along upstream reaches of the Powder 

River and its tributaries, but little flooding occurred at 

the mouth.

YELLOWSTONE RIVER

Although the peak flood discharge of the Yellowstone 

River at Miles City, Mont, (site 72), was the greatest
MAJOR RIVER BASINS 17

1 I [ I I 

Maximum inflow; 27,000 cubic feet per second

Top of active conservation 

storage; 1,116,000 acre-feet

Net

reservoir

inflow Reservoir storage

21 22 23 24 25 27 28 29 30 31

MAY 1978

3456 

JUNE 1978

FIGURE 12. Inflow, outflow, and storage contents of Bighorn Lake, Mont. Data from U.S. Bureau of Reclamation.

Q 18

z 

o

y 16 

en

cc

LLJ Q. 14

12

10

O 8

I 6

- 4

UJ

CD 

CC

< 2 

o

/Tongue River at State Line,near 

Decker, Montana (site 53)

N^^-Tongue River at Tongue 

\ River Dam, near Decker, 

\ Montana (site 56}

\ 

\ 

\ 

\

17 18 19 20 21 

MAY 1978

22 23

FIGURE 13. Hydrographs of discharge of the Tongue River near 

Decker, Mont., May 17-23, 1978.

at that site since records began in 1922, flood damage 

generally was minor. High flood stages due to ice jamming are not unusual on the Yellowstone River and 

have caused considerably more damage than the May 

1978 flood. No appreciable flooding occurred on the Yellowstone River downstream from Miles City, Mont., or 

upstream from the mouth of Pryor Creek near Billings, 

Mont. A flood hydrograph of the Yellowstone River at 

Miles City, Mont., is shown in figure 15.

PRYOR CREEK

Flooding was severe along Pryor Creek (sites 1, 4, 5, 

and 6), a small tributary of the Yellowstone River just 

downstream from Billings, Mont. Several State and 

county highway bridges were washed out along the 

Pryor Creek road, and substantial agricultural and residential property damage occurred on farms and 

ranches. A Burlington Northern Railroad bridge was 

washed out at the mouth of Pryor Creek, and the Big 

Horn Canal near Huntley was extensively damaged by 

Pryor Creek floodwaters. The only reported death resulting from the May 1978 flood occurred on Pryor 

Creek near Pryor when the victim left a flood-stranded
18 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

Maximum discharge of Belle Fourche River 

below Moorcroft, Wyoming (site 136); 15,300 

cubic feet per second on May 19 at 0300 hours

Maximum storage; 210,320 acre-feet 

on May 22 at 2100 hours

Reservoir storage 

(daily values) Top of active conservation storage 

199,871 acre-feet

Maximum discharge of Belle Fourche River 

below Keyhole Reservoir, Wyoming (site 137); 

1410 cubic feet per second on May 23 at 1100 hours

150

15 16

FIGURE 14. Inflow, outflow, and storage contents of Keyhole Reservoir, Wyo., May ISJune 5, 1978.

automobile and was evidently washed away by the current. Extensive urban property damage occurred near 

the town of Huntley (fig. 16). The peak discharge at the 

old gaging station, Pryor Creek near Billings (site 4), 

was more than four times that of the previous flow of 

record. The peak discharge at the upstream Pryor 

Creek gaging station (site 1) also was more than four 

times the maximum discharge previously known. At 

both sites the May 1978 flood exceeded the 1-percentchance flood discharge.

FLY CREEK

Fly Creek is another small (drainage area less than 

300 mi2) tributary of the Yellowstone River that 

flooded during May 1978. Residential property was inundated in and near the small community of Pompeys 

Pillar, and substantial agricultural flood damage 'occurred upstream from Pompeys Pillar. The peak discharge for May 1978 (site 7) was almost 4 times the previously known peak discharge and was greater than .the 

1-percent-chance flood.

BIGHORN RIVER

Flooding was widespread and severe throughout the 

Bighorn River basin, with some of the largest unit 

flows and greatest flood damages occurring on the 

Bighorn River tributaries of Soap Creek (site 26), 

Beauvais Creek (site 28), Rotten Grass Creek (site 27), 

and the Little Bighorn River (sites 32 and 35). Flooding 

on the Bighorn River was severe upstream from Yel-
18 20 21 22 23 24

MAY

FIGURE 15. Hydrograph of discharge of the Yellowstone River at Miles 

City, Mont, (site 72), May 18-24, 1978.

lowtail Dam1 (fig. 17) where the tributaries Fifteen 

Mile Creek (site 13), and Nowood River (site 15), contributed record flood discharges to the main stem. The 

May 1978 peak discharge on Fifteen Mile Creek was 

about a 1- percent-chance flood. A hydrograph of discharge for the Norwood River is shown in figure 18.

Flow on the main stem downstream from Yellowtail 

Dam was completely contained only as far downstream 

as the mouth of Soap Creek. Extreme runoff from Soap 

Creek, Rotten Grass Creek, Beauvais Creek, and the 

Little Bighorn River caused record flooding on the 

Bighorn River from St. Xavier to the mouth of the 

Bighorn River near Bighorn, Mont. The peak discharge 

of the Bighorn River at Bighorn (site 39) was more 

than twice the previous maximum of record and exceeded the 1-percent flood discharge. Agricultural flood 

damage was extensive along the Bighorn River (fig. 

19), and numerous irrigation structures were destroyed. Residential flood damage occurred at scattered 

locations along the main stem, particularly near St. 

Xavier and Hardin, Mont. A flood hydrograph of the 

Bighorn River at Bighorn is shown in figure 20.

'Confines the water of Bighorn Lake

MAJOR RIVER BASINS 19 

Soap Creek, Beauvais Creek, and Rotten Grass Creek

Flooding was severe on Soap Creek, Beauvais Creek, 

and Rotten Grass Creek, three relatively small (less 

than 150 mi2 drainage area) tributaries of the Bighorn 

River. Peak discharges during the May 1978 flood exceeded the 1-percent flood on all three streams and also 

greatly exceeded the previous peak of record on all 

three streams. Development along these streams is 

sparse, and residential property damage consequently 

was limited. Agricultural damage was extensive along 

all three streams, however, and severe channel erosion 

occurred on Beauvais Creek.

Little Bighorn River and Tributaries

Extensive flooding occurred on the Little Bighorn 

River from Pass Creek downstream to its confluence 

with the Bighorn River near Hardin, Mont. Upstream 

from Pass Creek, no flooding occurred on the Little 

Bighorn River main stem. Flooding was minor on smaller tributaries of the Little Bighorn River, as evidenced 

by the relatively small peak discharges of the Little 

Bighorn River tributary near Wyola, Mont, (site 31), 

and Long Otter Creek near Lodge Grass, Mont, (site 

34).

On Pass Creek near Wyola, Mont, (site 30), however, 

the May 1978 peak discharge was almost five times the 

previous peak flow of record. Residential property in 

Wyola was flooded, and several bridges were washed 

out upstream from Wyola. The May 1978 peak flow exceeded the 1-percent-chance flood.

Lodge Grass Creek also flooded extensively. The 

small community of Lodge Grass, Mont., in particular, 

suffered severe residential and commerical damage (fig. 

21). Flood damage upstream from the town was generally limited to agricultural range, cropland, roads, and 

bridges. At the only discharge- determination site (site 

33) on Lodge Grass Creek, the May 1978 peak discharge was about 10 percent less than the largest 

known peak discharge. At this site, about 17 mi upstream from Lodge Grass, the May 1978 flood was 

about a 2- percent-chance flood. At Lodge Grass the 

magnitude of the May 1978 flood was probably greater 

than a 2-percent-chance flood, because the urban damage was reported to be the greatest since at least 1900 

(Hardin Herald, 1978).

The Little Bighorn River caused extensive flood 

damage from the mouth of Pass Creek downstream to 

the confluence with the Bighorn River near Hardin. 

Substantial urban property damage occurred in and 

near the small community of Crow Agency (fig. 22). 

The 1-90 highway interchange near Crow Agency was 

severely damaged. The Burlington Northern Railroad
20 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

FIGURE 16. Flooding along U.S. Highway 312 near Huntley, Mont., from Pryor Creek overflow, May 19, 1978. View is westward. Photograph

by U.S. Bureau of Reclamation.

also suffered extensive track damage from Wyola to 

Hardin.

The May 1978 peak discharge at the gaging station 

downstream from Pass Creek (site 32) was more than 

twice the highest previously known. Downstream near 

Hardin (site 35), the May 1978 peak discharge of the 

Little Bighorn River was more than four times the 

highest previously known flood discharge. At both 

sites, the May 1978 peak was greater than the 1-percent-chance flood. Flood hydrographs for both Little 

Bighorn River gaging stations are shown in figure 23.

ROSEBUD CREEK

Minor flooding occurred on Rosebud Creek near its 

mouth and damage was slight. No flooding occurred upstream from the gage site near Colstrip, Mont, (site

44). The May 1978 flood on Rosebud Creek was greater 

than a 1- percent-chance flood at the mouth (site 45) but 

was only a 15-percent-chance flood near Colstrip.

TONGUE RIVER AND TRIBUTARIES

Extensive flooding occurred on the Tongue River and 

its larger tributaries upstream from the Tongue River 

Reservoir. Flooding was minor or nonexistent on the 

upper Tongue River stations near Dayton, Wyo. (sites 46 

and 47), but record flooding occurred near the WyomingMontana border (site 53). However, flood damage was 

minor along the main stem of the river because of sparse 

development. Overbank flooding was minor on the 

Tongue River downstream from the Tongue River Reservoir. Tributaries downstream from the reservoir did not 

flood appreciably.
MAJOR RIVER BASINS 21

FIGURE 17. Flooded mobile home along the east bank of the Bighorn River near Manderson, Wyo., May 19, 1978.

Upstream from the reservoir, Goose Creek (site 50) 

and Prairie Dog Creek (site 52) flooded extensively and 

were the largest contributors to the record Tongue 

River flows at the State line. Smaller tributaries did 

not flood significantly anywhere along the Tongue 

River.

The May 1978 peak discharge on the Tongue River at 

the State line site was more than twice the maximum 

previously known. This peak flow exceeded the 1-percent-chance flood. The May 1978 peak flow on Goose 

Creek was near the maximum peak flow previously 

known and was about a 3-percent-chance flood. A flood 

hydrograph for Goose Creek is shown in figure 24. The 

Prairie Dog Creek flood peak was more than five times

greater than the previously known maximum and was 

about a 1-percent-chance flood.

POWDER RIVER AND TRIBUTARIES

Flooding within the Powder River basin generally 

was limited to the main stem Powder River and its 

larger tributaries. Overbank flooding was probably 

most severe on the Powder River from Sussex, Wyo. 

(site 89), to Broadus, Mont, (site 103). Some urban 

property flood damage occurred at Broadus, and agricultural damage occurred throughout the reach. From 

Broadus to Locate, Mont, (site 116), the May 1978 peak
22

3500

18 19 

MAY

20 21

MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

CHEYENNE RIVER BASIN

CHEYENNE RIVER

Flooding in the Cheyenne River basin was extensive 

and record floods occurred on the Cheyenne River and 

several of its tributaries. In the upper reaches of the 

Cheyenne River, Antelope Creek (site 118) and Dry 

Fork Cheyenne River (site 119) contributed substantially to the extensive flooding of the Cheyenne River 

near Dull Center, Wyo. (site 120). Flow records at 

these sites are unavailable prior to 1976. However, 

floodmarks and information furnished by local residents 

indicate that larger flows have occurred in the past.

Farther downstream, record or near-record floods on 

Black Thunder Creek and Lance Creek caused extensive agricultural damage. Considerable road and bridge 

damage also took place, particularly on Black Thunder 

Creek. A road washout on Lance Creek that resulted 

from a heavy load of debris in the floodwaters is 

dramatically illustrated in figure 26. The peak discharge on Black Thunder Creek (site 122) was more 

than six times the largest discharge during the 6-year 

period on record. The peak discharge on Lance Creek 

(site 126), a 4-percent-chance flood, was slightly less 

than the largest discharge previously known. A flood 

hydrograph for Lance Creek is shown in figure 27. The 

first peak on the hydrograph resulted from the intense 

but more isolated rain on May 16 that fell in the headwater area near Orin, Wyo. The May 16 storm in this 

area caused the extreme flow of Sand Creek near Orin 

(note plotting of site 161 on fig. 11), which inundated 

and closed Interstate Highway 25 for a short time.

The main stem of the Cheyenne River also flooded 

extensively downstream from the mouth of Lance 

Creek and caused considerable agricultural and road 

damage (fig. 28). At the gaging station near Riverview, 

Wyo. (site 127), the May 1978 peak discharge of the 

Cheyenne River was almost twice the maximum flood 

previously known and was greater than the 1-percentchance flood.

Downstream from Riverview the peak discharge of 

the Cheyenne River attenuated as far as the confluence 

of Beaver Creek, where large inflow was again supplied. Thus, at the gaging site near Edgemont, S. Dak. 

(site 130), the peak discharge of the Cheyenne River 

was about the same as at site 127. The May 1978 peak 

discharge near Edgemont was more than twice the 

highest peak previously known and was about a 1-percent-chance flood.

BELLE FOURCHE RIVER

Severe flooding occurred on the Belle Fourche River 

and some of its larger tributaries. Agricultural damage

FIGURE 18. Hydrograph of discharge of the Nowood River near 

Tensleep, Wyo. (site 15), May 16-21, 1978.

flow was reduced from 30,000 to 27,400 ft3/s by channel 

and valley storage, with a corresponding decrease in 

flooding. The May 1978 peak discharge on the Powder 

River exceeded the previous maximum for the period of 

record at Moorhead, Mont, (site 101), and at Broadus, 

Mont., but probably was not as great as the 1923 flood. 

At both sites the May 1978 peak was about a 3-percentchance flood. At the other Powder River main-stem 

stations (sites 81, 89, 92, and 116), peak flows ranged 

from about a 4- to a 7-percent-chance flood.

Powder River tributaries that flooded significantly 

were the South Fork Powder River (site 82) and Salt 

Creek (site 88) in Wyoming, and the Little Powder 

River in both Montana and Wyoming. Damage along 

these streams was relatively minor because of sparse 

development. Peak discharges on the South Fork Powder River during May 1978 ranged from a 20-percentchance flood (site 83) to about a 1-percent-chance flood 

(site 82). The peak flow of Little Powder River near 

Broadus (site 112) was equivalent to that of a 2-percent-chance flood. A flood hydrograph for the Little 

Powder River above Dry Creek in Wyoming (site 109) 

is shown in figure 25.
MAJOR RIVER BASINS

I

FIGURE 19. Flooded farmsteads on the left bank of the Bighorn River, 2 mi northeast of Hardin, Mont., May 19, 1978. View is northwestward.

Photograph by U.S. Bureau of Reclamation.

60

50

O oc

30

< DO 20 i =) 

o o

^LL D °io

17 18 19 20 

MAY

21 22

FIGURE 20. Hydrograph of discharge of the Bighorn River at 

Bighorn, Mont, (site 39), May 17-22, 1978.

was substantial along the entire main stem in Wyoming. Record flood levels were reached at all gaging stations (sites 131 and 132, near Piney; site 136, below 

Moorcroft; and site 137, below Keyhole Reservoir). 

Some unusual road-culvert damage caused by the large 

flows of the upper Belle Fourche River is shown in figure 29.

Tributary streams where high flows were recorded 

and agricultural damage occurred include Caballo 

Creek (site 133) and Donkey Creek (site 135). A flood 

hydrograph for Donkey Creek near Moorcroft, Wyo. 

(site 135), is shown in figure 30.

The May 1978 peak discharges on the Belle Fourche 

River near Piney, Wyo. (sites 131 and 132), were greatly affected by impounded water released when an 

earthen dam washed out upstream. On the Belle 

Fourche River below Moorcroft, Wyo. (site 136), the 

1978 peak discharge was more than three times the 

previous maximum discharge during the period of record and was the greatest since the flood in 1908. The
24 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

FIGURE 21. Flooding at Lodge Grass, Mont., May 19, 1978. Lodge Grass is situated at the mouth of Lodge Grass Creek at the Little Bighorn

River. View is southeastward. Photograph by U.S. Bureau of Reclamation.
MAJOR RIVER BASINS 25

FIGURE 22. Flooding of the Little Bighorn River in the town of Crow Agency, Mont., at the Interstate Highway 1-94 interchange, May 19,

1978. View is northward. Photograph by U.S. Bureau of Reclamation.
26

23

20

15

O 

O

LLJ 

U)

CC 

UJ 

O_

o

CD

D 

O

LL. 

O

Q

CO 

O

m c CD 5

cc 

<

I

o

CO

10

MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

6000

Little Bighorn River 

near Hardin, Montana 

(site 35)

Little Bighorn River 

below Pass Creek, 

near Wyola, 

Montana (site 32)

17 18 19 20 21 22 

MAY

FIGURE 23. Hydrographs of discharge of the Little Bighorn River, 

May 17-22, 1978.

6000

Q

§ 5000

o

LU 

(/)

CC

o! 4000

y 3000

GO 

D 

O.

~ 2000

LU

CD

CC

1000

17 18 19 20 21 

MAY

22

FIGURE 24. Hydrograph of discharge of Goose Creek below Sheridan, 

Wyo. (site 50), May 17-22, 1978.

17 19 20 

MAY

21 22

FIGURE 25. Hydrograph of discharge of the Little Powder River 

above Dry Creek near Weston, Wyo. (site 109), May 17-22, 1978.

May 1978 peak exceeded the 1-percent-chance flood at 

site 136.

PLATTE RIVER BASIN 

MEDICINE BOW RIVER

Severe flooding occurred on the Little Medicine Bow 

River near Medicine Bow, Wyo. (site 141). Agricultural 

damage was substantial, but little structural damage 

occurred because of sparse development.

The flood flow from the Little Medicine Bow River 

contributed heavily to flooding on the Medicine Bow 

River. Upstream from Seminoe Reservoir (site 142), 

the May 1978 peak was about a 3-percent-chance flood. 

A discharge hydrograph for the Medicine Bow River is 

shown in figure 31.

NORTH PLATTE RIVER

The North Platte River basin has many reservoirs, 

and the manipulation of storage and releases during the 

May 1978 flood reduced the flood potential from the 

major tributaries. The flood peak on Deer Creek, at 

Glenrock, Wyo. (site 151), was a 3-percent chance flood; 

the peak on Box Elder Creek, at Box Elder, Wyo. (site 

155), was a 3-percent-chance flood; and that on Sand 

Creek, near Orin, Wyo. (site 161), was a 5-percentchance flood.
FLOOD DAMAGE 27

FIGURE 26. Flooding of Lance Creek near Bright, Wyo., May 19, 1978. The force of debris and water would have destroyed the bridge had

the water not breached the road.

The May 1978 peak on the main stem of the North 

Platte River in Wyoming was well below the record 

flow of 1965 near Glenrock (site 154) and at Orin (site 

163). Glendo Reservoir, just downstream from Orin, remained well below the maximum storage level. Downstream from the reservoir, the flow in the North Platte 

River was about normal for May.

FLOOD DAMAGE

One life was lost as a direct result of the May 1978 

flooding, and damage to roads, bridges, railroads, irrigation structures, cropland, homes, and businesses was 

severe. On May 29, President Carter declared the 

flooded areas of Montana and Wyoming major disaster 

areas, thereby qualifying the areas for various Federal 

funds for relief and recovery efforts. In Montana, the

initial disaster declaration affected the counties of Big 

Horn, Powder River, Rosebud, Treasure, and Yellowstone. In Wyoming, the affected counties were Big 

Horn, Campbell, Converse, Crook, Hot Springs, 

Johnson, Park, Natrona, Niobrara, Sheridan, 

Washakee, and Weston. Carbon and Stillwater Counties in Montana were subsequently added to the list of 

disaster-affected counties, but estimated damages in 

the two counties were considerably less than in the 

other flood-damaged counties.

Estimates of flood damage were compiled by various 

State and Federal agencies and were made available by 

the Federal Disaster Assistance Administration (Dave 

Grier, written commun., 1978), the U.S. Agricultural 

Stabilization and Conservation Service (James Eggen, 

oral commun., 1979), and the Wyoming Disaster and 

Civil Defense Agency (1978). Total estimated damages 

for May 1978 are listed in table 5.
28 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

7500

7000 -

18 19 20 

MAY

21 22

FIGURE 27. Hydrograph of discharge of Lance Creek near Riverview, 

Wyo. (site 126), May 17-22, 1978.

Agricultural losses were much greater than either 

private- or public- facility losses in both Montana and 

Wyoming (table 5). The estimates for crop loss included 

such items as field washout of newly planted crops and 

sediment deposition in fields. The livestock loss figure 

was large; many newborn lambs and calves perished 

from the flooding and cold weather, and herds of cattle 

in Wyoming drowned in the rapidly rising water in 

some steep-sided river valleys. Miscellaneous agricultural damage included the cost of fence replacement; removal of debris from fields; and grading, shaping, and 

repair of private irrigation facilities.

In the public-damage category, severe road and 

bridge damage occurred in both States. In Montana, 

numerous public irrigation facilities also were washed 

out or severely damaged.

SEDIMENTATION

MONTANA

Sedimentation, which includes erosion, deposition, 

and other physical processes, was unusually large in

TABLE 5. Summary of flood damage

[Data from the Federal Disaster Assistance Administration, the U.S. Agricultural Stabilization and Conservation Service, and the Wyoming Disaster 

and Civil Defense Agency]

Type of damage Wyoming Total

Private damage:

Residences

Businesses

Agricultural damage:

Buildings and equipment

Crop loss

Livestock loss

Miscellaneous

Public damage:

Road systems

Public utilities

Debris removal

Water-control facilities

Parks and recreational

facilities

Other public damage

$ 2,850,000

2,500,000

350,000

10.915,300

3,025,000

2,630,300

2,062,000

3,198,000

3.798,400

1.418,400

89,500

28,750

1,572,000

194.250

495,500

$ 2,500,000

2,000,000

500,000

12.320,000

190,000

4,800.000

4,460,000

2.870,000

1,500,200

1,266.600

85.100

48,600

32.500

6.800

60.600

$ 5.350,000

4,500,000

850,000

23,235,300

3,215,000

7,430,300

6,522.000

6,068,000

5,298,600

2,685,000

174,600

77,350

1,604,500

201,050

556,100

Total damage 17,563,700 16,320,200 33,883,900

both Montana and Wyoming as a result of the flooding 

of May 1978. In comparing sediment data for three 

Montana stations on the Powder River, suspended-sediment concentration and suspended-sediment discharge 

obviously decreased as the peak flows moved downstream. The inability of the channel to contain the flood 

flow forced the water out onto the flood plain, where 

decreased velocities caused a settling of sediment. At 

all stations the maximum concentration preceded the 

maximum sediment discharge. Maximum daily suspended-sediment discharges as listed in table 6 exceeded the previous recorded maximum at all stations. 

However, only the Powder River at Moorhead had a 

mean daily sediment concentration that exceeded any 

previously recorded values; that concentration was 

41,000 mg/L (milligrams per liter).

Sediment movement in the Tongue River was considerably less than that in the Powder River, partly because the Tongue River Reservoir moderated flows and 

trapped much of the sediment from upstream sources. 

For the Tongue River in Montana, maximum mean 

daily suspended-sediment concentration was 5,900 mg/ 

L and suspended-sediment discharge was 84,400 ton/d 

at Miles City (site 71) on May 18. The short period of 

record does not justify historical comparisons.

WYOMING

Precipitation from storms of April 26-30 and May 2-8 

provided saturated soil conditions favorable to flooding 

and erosion. Subsequent intense rains May 16-19 produced the stream flooding and large increases in sediment discharge. The contribution to sediment loads was
SEDIMENTATION 29

FIGURE 28. Bridge on the Cheyenne River near Riverview, Wyo., May 25, 1978. View from the right bank shows approach to bridge completely washed out. Washout probably occurred late May 19 or early May 20, 1978.
30 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

FIGURE 29. Flood damage along the Belle Fourche River below Rattlesnake Creek near Piney, Wyo. (site 131), May 19, 1978. Upstream ends 

of culverts were bent upward, one more than 90°. Flow over the road beginning at left side of photograph and flow through culverts caused 

extensive erosion on the downstream side of the road.

from enlargement of gullies, headcutting (see fig. 32), 

sloughing of river banks, and degrading of the stream 

channels.

Large suspended-sediment concentrations and suspended-sediment discharge were prevalent in most 

streams. For example, a new maximum daily suspended-sediment discharge for the period of record, 

April 1946 to September 1957, October 1967 to September 1971, and January 1975 to May 1978, was measured at Powder River at Arvada, Wyo. (site 92). The 

suspended-sediment discharge on May 20, 1978, was 

2,810,000 tons transported by a mean daily discharge of 

22,600 ft3/s with a mean daily concentration of 46,000 

mg/L. The previous maximum at this site was 2,340,000

tons on May 24, 1952. Another example of large quantities of sediment was the suspended-sediment discharge of 460,000 tons on May 20, 1978, at Bighorn 

River near Kane, Wyo. (site 18). This sediment discharge was obtained from the suspended-sediment 

transport curve (Colby, 1956) of figure 33. The mean 

daily discharge on this date was 17,900 ft3/s. The 

maximum suspended-sediment discharge at this site on 

June 25, 1946, was 972,000 tons, computed from mean 

daily values of concentration and flow. The period of record at this site is March 1946 to September 1964 and 

December 1969 to May 1978. Sediment data collected 

during the flood period in both Montana and Wyoming 

are summarized in table 7 (at end of report).
5000

19 20 

MAY

21

SEDIMENTATION

6000

8 5000

LLJ 

C/5

cc

LLJ

°" 4000

co 3000 

O

g 2000

cc

X 

O

§ 1000 

500

22

FIGURE 30. Hydrograph of discharge of Donkey Creek near Moorcroft, Wyo. (site 135), May 17-22, 1978.

17 18 19 20 

MAY

21 22

FIGURE 31. Hydrograph of discharge for the Medicine Bow River 

above Seminoe Reservoir near Hanna, Wyo. (site 142), May 17-22,

1978.

FIGURE 32. Headcutting near the mouth of Black Thunder Creek, near Hampshire, Wyo. (site 122), May 19, 1978.
32 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

1,000,000 TABLE 6. Daily suspended-sediment discharge for the 

Powder River in Montana

Site

Maximum

Date suspended-sediment 

discharge (tons)

At Moorhead (site 101) 

At Broadus (site 103) 

Near Locate (site 116)

May 20, 1978

May 21, 1978

May 22, 1978

2,230,000

1,570,000

739,000

AERIAL PHOTOGRAPHY

Aerial photographs were taken at or near the crest of 

the flood on several streams in Montana. The blackand-white photographs taken by the Montana Department of Highways are useful in identifying inundated 

areas. The areas flown and the photography numbers 

and scales are listed in table 8. The approximate location of the flight lines is shown in figure 34. The photographs are on file in the U.S. Geological Survey district 

office, Helena, Mont.

FLOOD-HYDROGRAPH DATA

Gage heights and discharges at selected times during 

the flood at streamflow-gaging stations are given in 

table 9 (at end of report). All continuous-record stations 

where the 1978 peak flow was at least that of a 10- percent-chance flood are included. The period included begins before the start of the major rise of the streams 

and extends to an arbitrary cutoff point when the discharge approached that of the antecedent flow. The 

time intervals used to identify stage and discharge data 

in table 9 provide sufficient detail to adequately define 

the flood hydrograph.

SUMMARY

Intense rains and some snow, produced by imbedded 

convective cells associated with a cold front, occurred 

over southeastern Montana and northeastern Wyoming 

May 16-19, 1978. Precipitation on previously saturated 

ground caused widespread flooding in the Yellowstone, 

Cheyenne, Belle Fourche, and North Platte River 

drainages. Maximum measured rainfall was 7.60 in. 

within 72 hours at Lame Deer, Mont. The storm established a precipitation record for that area for May, but 

ranks third when all months are considered.

Q 100,000

- 10,000

1000

100

TT

100 1000 10,000

DISCHARGE, IN CUBIC FEET PER SECOND

100,000

FIGURE 33. Suspended-sediment transport curve of the Bighorn 

River near Kane, Wyo. (site 18), October 1969 to September 

1978.

Peak discharges were determined at 164 selected 

sites in the area. Peak discharges at 48 of these sites 

exceeded the maximum peak discharges previously 

known and equaled or exceeded the 1-percent-chance 

flood at 24 sites.

Peak flows and stages on several rivers were substantially reduced by large reservoirs in the area. Peak 

discharge of the Yellowstone River at Miles City, 

Mont., was reduced by about 22,000 fts/s as a result of 

storage in Big Horn Lake. Keyhole Reservoir in 

Wyoming reached a record storage level and record 

peak outflow as a result of the storm. The storage capacity of the reservoir reduced the peak discharge by 

about 14,000 fts/s in the reach below the dam.

Flood damage was extensive, exceeding $33 million 

in the two States. Nineteen counties were declared 

major disaster areas.

Daily suspended-sediment discharges were particularly large in the Powder River basin and exceeded 

previously recorded maximum values at four sites. The 

maximum daily suspended-sediment discharge was 

2,810,000 tons on May 20 for the Powder River near 

Arvada, Wyo.
SUMMARY 

TABLE 8. Aerial photography of the May 1978 flood in Montana

[Photography by Montana Department of Highways]

33

Scream

Ye Hows Cone River

Blue Creek

Pryor Creek

Fly Creek

Bighorn River

Liccle Bighorn

Pass Creek

Tongue River

FlighC 

line 

number

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

Location

Pompeys Pillar Bridge

Hysham Co Bighorn River

Hysham Co Bighorn River

Mouth Co Basin Creek

U.S. Highway 87 Co HunCley

U.S. Highway 87 Co HunCley

Hunt ley area

HunCley area

Pompeys Pillar area

Mouth Co Bighorn County

North Hard in area

North Hardin area

MouCh Co Crow Agency

Mouth to Crow Agency

Mouth to Crow Agency

Crow Agency area

Crow Agency to Wyola

Wyola to State line

Tongue River Reservoir 

to State line

Tongue River Reservoir 

to State line

Decker to Ashland

Decker to Ashland

Decker to Ashland

Decker to Ashland

Decker to Ashland

Photograph number

352-10 to 12

FLT 1:353-77 to 91

FLT 2:353-92 to 100

352-194 to 200

FLT 1:352-150 to 169

FLT 2:352-170 to 180

FLT 1:352-181 to 189

FLT 2:352-190 to 193

352-1 to 9

353-101 to 104

FLT 1:: 352-14 to 17

FLT 2:352-18 to 27

FLT 1:352-127 to 134

FLT 2:352-135 to 139

FLT 3:352-140 to 149

352-28 to 43

352-44 to 89

352-90 to 100

FLT 1:352-101 to 111

FLT 2:352-113 to 126

FLT 1:353-1 to 12

FLT 2:353-13 to 29

FLT 3:353-30 to 38

FLT 4:353-39 to 41

FLT 5:353-42 to 76

Date 

in 

May

19

20

20

19

19

19

19

19

19

20

19

19

19

19

19

19

19

19

19

19

20

20

20

20

20

Scale

1:10,000

1:12,000

1:12,000

1:10,000

1:9,600

1:9,600

1:9,600

1:9,600

1:10,000

1:12,000

1:10,000

1:10,000

1:16,000

1:16,000

1:16,000

1:10,000

1:10,000

1:10,000

1:12,000

1:12,000

1:12,000

1:12,000

1:12,000

1:12,000

1:12,000
34 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

108° 107°

18

EXPLANATION

Flight line Number corresponds 

to Table 8

10 20 30 MILES

6 10 20 30 40 KILOMETERS

FIGURE 34. Location of flight lines along streams where aerial photographs were obtained at or near crest of flood, May 19-20, 1978.
REFERENCES 35

REFERENCES

Colby, B. R., 1956, Relationship of sediment discharge to streamflow: 

U.S. Geological Survey open-file report, 170 p.

Hardin Herald, 1978, Flood is century's worst disaster: Hardin, 

Mont., v. 71, no. 21, May 25, p. 1.

Johnson, M. V., and Omang, R. J., 1976, A method for estimating 

magnitude and frequency of floods in Montana: U.S. Geological 

Survey Open- File Report 76-650, 35 p.

Lott, G. A., 1976, Precipitable water over the United States, vol. 1, 

Monthly means: National Weather Service, NOAA Technical 

Report NWS 20, 173 p.

Miller, J. F., 1964, Two- to ten-day precipitation for return periods 

of 2 to 100 years in the contiguous United States: U.S. Weather Bureau Technical Paper 49, 29 p.

Miller, J. F., Frederick, R. H., and Tracy, R. J., 1973, Precipitationfrequency atlas of the western United States, vol. 1 Montana: National Weather Service, NOAA Atlas 2, 41 p.

National Weather Service, Hydrometeorological Branch, 1979, Notes 

as an extension of NOAA Technical Memorandum NWS 

HYDRO 33: Unpublished note on file at the Silver Spring,

Md., office of the National Weather Service.

Omang, R. J., and Hull, J. A., 1978, Annual peak discharges from 

small drainage areas in Montana through September 1977: 

U.S. Geological Survey Open-File Report 78-219, 204 p.

Riedel, J. T., and Ho, F. P., 1979, Precipitable water over the 

United States, vol. 2, Semi-monthly maxima: National Weather Service, NOAA Technical Report NWS 20, 359 p.

U.S. Army, Corps of Engineers, updated annually since 1945, Storm 

rainfall in the United States, Depth-area-duration data. 

U.S. Bureau of Reclamation, 1979, Report on operations of 

Bighorn Lake during 1978: Unpublished data on file in Billings, 

Montana, office, 52 p.

U.S. Environmental Science Services Administration, 1968, Weather 

atlas of the United States (original title: Climatic atlas of the 

United States): U.S. Department of Commerce, reprinted 

1975, 262 p.

U.S. Water Resources Council, 1977, Guidelines for determining 

flood flow frequency: Washington, D.C., Bulletin 17A, 26 p.

Wyoming Disaster and Civil Defense Agency, 1978, Conditions resulting in the north central and eastern Wyoming flood disaster: Cheyenne, Wyoming Disaster and Civil Defense Agency, 

89 p.
TABLES 3, 7, AND 9
TABLE 3. Summary of flood stages and discharges

[mi2, square miles; ft, feet; ft3/s, cubic feet per second]

Site

number

(fig. 1)

1

2

3

4

5

6

7

8

9

10

11

12

13

14

Permanent

station

number

06216000

06216200

06216300

06216500

 

 

06217750

06259000

06265200

06265600

06267260

06267400

06268500

06268600

Site of flooddischarge determination

Pryor Creek at Pryor ,

Mont.

West Wets Creek near

Billings, Mont.

West Buckeye Creek near

Billings, Mont.

Pryor Creek near

Billings, Mont.

Pryor Creek at 1-94

crossing near Hunt ley,

Mont.

Pryor Creek at Hunt ley,

Mont.

Fly Creek at Pompeys

Pillar, Mont.

Wind River below Boysen 7

Reservoir, Wyo.

Sand Draw near Thermopclis,

Wyo.

Tie Down Gulch near

Worland, Wyo.

North Prong East Fork

Nowater Creek near

Worland, Wyo.

East Fork Nowater Creek

near Colter, Wyo.

Fifteenmile Creek near

Worland, Wyo.

Bighorn River at 10

Worland, Wyo.

Drainage

area

(mi2)

117

8.80

2.64

440

606

606

285

,701

6.33

1.78

3.77

149

518

,810

Maximum flood

previously known

Datum of Period

gage above of

NGVD of 1929 record

(ft) Gage

Date height Discharge

(ft) (ft^/s)

b3,900 1921-24; 6-26-69 6.13 468

1966-78

1955-78 4-26-64 6.90 565

1955-73 7-18-69 5.05 924

C 3,310 1911-24; 4-26-64 15.04 3,720

1938-53;

1953-73

 

 

C 2,870 1968-78 2-14-71 9.23 2,680

4,608.58 1951-78 7-07-67 13.35 13,500

1960-78 6-09-60 822.58 2,490

 1961-78 8-31-63 8.62 328

1964-78 9-18-67 5.47 394

C4,165 1971-78 7-06-75 3.68 1,270

C4,070 1951-78 5-22-52 i 5.77 3,300

4,035.78 1965-69 6-23-67 13.69 15,900

Maxim

Gage 

Day height 

(ft) 

19 8.88 

19 6.81 

19 3.68 

19 18.90 

19 

19 

19 15.94 

19 

19 4.49 

19 6.11 

18 5-29 

18 6.65 

18 10.58 

19 14.45 
TABLE 3. Summary of flood stages and discharges Continued

Site Permanent

number station 

(fig. 1) number

15

16

17

18

19

20

21

22

23

24

25

26

06270000

06274250

06279090

06279500

06282000

06284200

06284400

06284500

06284800

06285100

06285400

06287500

Site of flooddischarge determination

Nowood River near

Tensleep, Wyo.

Elk Creek near Basin, Wyo.

Shell Creek near Greybull,

Wyo.

Bighorn River near 15

Kane, Wyo.

Shoshone River below 1

Buffalo Bill Reservoir,

Wyo.

Shoshone River at 1

Will wood, Wyo.

Shoshone River near 2

Garland, Wyo.

Bitter Creek near

Garland, Wyo.

Whistle Creek near

Garland, Wyo.

Shoshone River near 2

Love 1 1 , Wyo .

Sage Creek at Sidon Canal

near Deaver, Wyo.

Soap Creek near St.

Drainage

area 

(mi2)

803

96.9

560

,765

,538

,980

,036

80.5

101

,350

341

98.3

Datum of

gage above 

NGVD of 1929 

(ft)

C4,420

 

 

C3,660

C4,900

C4,300

4,073.67

C4,080

C4,150

C3,850

C4,020

C 3,250

Maximum flood 

previously known 

Period

of 

record 

Gage 

Date height Discharge

(ft) (ft3/s )

1938-43; 6-16-55 il2.30 3,330

1950-55;

1972-78

1959-78 6-06-67 10.91 4,260

1951;

1965-78

1928-78 6-16-35 ill. 10 25,200

1921-78 5-28-28 ilO.62 14,700

1974-78 6-20-74 10.43 12,100

1958-78 7-01-67 is.76 13,300

1950-53; 7-04-75 4.74 1,230

1957-60;

1968-78

1958-60; 7-03-75 12.44 4,780

1968-78

1966-78 7-01-67 6.49 13,400

1958-60; 6-08-58 9.22 2,250

1968-78

1911-12; 4-28-63 14.96 4,170

Maxi

Gag

Day heig

(ft

19 12.

19 9.

19 7.

20 9.

19 

19 7.

19 7.

17 3.0

18 7.4

18 6.2

19 5.3

19 16.9

27

Xavier, Mont.

06288000 Rotten Grass Creek near 

St. Xavier, Mont.

147 C 3,150

1913; 

1939-53; 

1963; 

1967-72

1913-19; 2-28-72 9.16

1919-22;

1967-72

900 19 13.6
TABLE 3. Summary of flood stages and discharges Continued

Site Permanent

number station 

(fig. 1) number

28

29

30

31

32

33

34

35

36

37

38

39

40

41

06288200

06289000

06290000

06290200

06290500

06291500

06293300

06294000

06294400

06294600

06294690

06294700

06294930

06294940

Drainage

Site of flood" area 

discharge determination (mi*)

Beauvais Creek near St. 100

Xavier, Mont.

Little Bighorn River at 193

State line near Wyola,

Mont.

Pass Creek near Wyola, 111

Mont.

Little Bighorn River 4.43

tributary near

Wyola, Mont.

Little Bighorn River 428

below Pass Creek

near Wyola, Mont.

Lodge Grass Creek above 80.7

Willow Creek diversion

near Wyola, Mont.

Long Otter Creek near 11.7

Lodge Grass, Mont.

Little Bighorn River 1,294

near Hardin, Mont.

Andresen Coulee near 2.35

Custer, Mont.

Tullock Creek tributary 8.63

near Hardin, Mont.

Tullock Creek near 446

Bighorn, Mont.

Bighorn River at 22,885

Bighorn, Mont.

Sarpy Creek tributary 4.44

near Cols trip, Mont.

Sarpy Creek near Hysham, 453

Maximum flood 

previously known Maxim

Datum of Period

gage above of 

NGVD of 1929 record 

(ft) Gage Gage 

Date height Discharge Day heigh

(ft) (ft3/s) (ft) 

C3,350 1967-77 6-09-68 8.00 1,600 19 9.5

C4,450 1939-78 6-03-44 4.87 2,730 24 3.5

1935-56 6-04-44 4.82 1,150 19 10.9

 1973-78 6-10-77 3.79 201 19 3.3

C3,600 1939-75; 6-14-63 7.43 3,630 19 10.0

1977-78

C4,360 1939-74 6-09-64 6.14 1,130 19 6.2

1973-78 4-04-75 4.60 J76 19 8.0

2,891.64 1953-78 4-02-65 4,520 19 11.2

 1963-78 6-04-63 1.57 40 18 .4

 1973-78 3-03-75 3.38 171 18 1.67 

C 2,770 1974-78 3-02-76 7.40 1,960 18 6.3

C2,690 1945-78 6-24-47 8.79 26,200 20 14.15 

1972-78 1972 4.33 194 18 4.77 

C2,680 1973-78 3-04-75 12.43 428 21 11.6

Mont.
TABLE 3. Summary of flood stages and discharges Continued 

Site

number

(fig. 1)

42

43

44

45

46

47

48

49

50

51

52

53

54

55

Permanent

station

number

06294985

06294995

06295250

06296003

06297480

06298000

06299900

 

06305500

06306100

06306250

06306300

06306900

06306950

Drainage

Site of flood- area

discharge determination (mi?)

East Fork Armells Creek 1.87

tributary near

Colstrip, Mont.

Armells Creek near 370

Forsyth, Mont.

Rosebud Creek near 799

Colstrip, Mont.

Rosebud Creek at mouth, 1,302

near Rosebud, Mont.

Tongue River at Tongue 202

River Campground

near Dayton, Wyo.

Tongue River near 204

Dayton, Wyo.

Slater Creek near 18.0

Monarch, Wyo.

Jackson Creek near 7.44

Big Horn, Wyo.

Goose Creek below 392

Sheridan, Wyo.

Squirrel Creek near 33.6

Decker, Mont.

Prairie Dog Creek near 358

Acme, Wyo.

Tongue River at State 1,477

line, near Decker,

Mont.

Spring Creek near 34.7

Decker, Mont.

Leaf Rock Creek near 6.14

Datum of Period

gage above of

NGVD of 1929 record

(ft)

1973-78

C 2,560 1974-78

C3,000 1974-78

2,480 1974-78

4,210 1974-78

4,060 1918-29;

1940-78

1967-78

 

3,701.36 1941-78

3,680 1975-78

3,450 1970-78

3,429.14 1960-78

1958-78

1958-78

Maximum flood 

previously known

Date

1-21-75

1-21-75

5-17-75

2-26-75

5-10-77

6-03-44

6-15-67

 

6-16-63

May 1975

3-05-75

6-15-67

2-14-71

6-15-63

Gage

height

(ft)

2.72

4.80

6.92

5.78

4.30

6.45

61.30

 

7.82

2.33

6.01

10.86

6.50

6.77

Discharge

(ft3/s)

50

k500

406

kl,200

k2,750

3,400

1,700

 

5,450

12

738

7,480

1,400

222

Day

18

20

21

19

18

18

18

18

18

18

19

19

18

19

Maximu

Gage

height

(ft)

3.59

4.91

9.02

6.78

3.29

3.38

59.97

 

8.33

7.27

12.60

14.25

2.79

.94

Kirby, Mont.
TABLE 3. Summary of flood stages and discharges Continued

Site Permanent

number station 

(fig. 1) number

56

57

58

59

60

61

62

63

64

65

66

67

68

69

06307500

06307520

06307600

06307620

06307700

06307720

06307740

06307780

06307830

06307930

06308100

06308200

06308330

06308340

Drainage

Site of flood- area 

discharge determination (mi')

Tongue River at Tongue 1,770

River Dam, near

Decker, Mont.

Canyon Creek near 50.2

Birney, Mont.

Hanging Woman Creek near 470

Birney, Mont.

Tie Creek near Birney, 18.7

Mont.

Cow Creek near Fort Howes 8.37

ranger station, near

Otter, Mont.

Brian Creek near 8.03

Ashland, Mont.

Otter Creek near 707

Ashland, Mont.

Stebbins Creek at mouth, 19.9

near Ashland, Mont.

Tongue River below 4.062

Brandenberg bridge,

near Ashland, Mont.

Jack Creek near 5.47

Volborg, Mont.

Sixmile Creek tributary .24

near Epsie, Mont.

Basin Creek tributary .14

near Volborg, Mont.

Deer Creek tributary 1.65

near Volborg, Mont.

La Grange Creek near 3.66

Datum of Period

gage above of 

NGVD of 1929 record 

(ft)

3,344.40 1939-78

1972-78

3,150 1973-78

1973-78

1972-78

1973-78

C 2,920 1972-78

1963-78

C 2,710 1973-78

1973-78

1973-78

1955-78

1973-78

1973-78

Maximum flood 

previously known Maxim

Gage Gage 

Date height Discharge Day heigh

(ft) (ft3/s) (ft) 

6-15-67 8.20 7,340 20 20.0

6-14-76 2.28 182 18 .9

3-04-75 9.77 986 19 11.5

3-03-75 2.36 9 19 1.4

1972 2.39 43 18 1.6

3-01-75 3.75 93 19 1.9

3-06-75 7.05 341 21 7.3

3-19-69 4.45 570 19 3.4

6-18-67 k5,740 22 9.9

5-05-75 4.56 271 18 5.6

6-18-72 3.18 74 18 4.3

7-02-58 6.96 390 18 1.3

1973 11.55 1,170 18 4.2

5-06-75 7.62 378 18 5.1

Volborg, Mont.
TABLE 3. Summary of flood stages and discharges Continued

Maximum flood

previously

Site

number

(fig. 1)

70

71

72

73

74

75

76

77

78

79

80

81

82

Permanent

station

number

06308400

06308500

06309000

06309080

06309200

06309260

06309270

06309280

06309450

06309460

06311400

06312500

06312700

Site of flooddischarge determination

Pumpkin Creek near

Miles City, Mont.

Tongue River at 5

Miles City, Mont.

Yellows tone River at 48

Miles City, Mont.

Deep Creek near

Kinsey, Mont.

Middle Fork Powder River

near Barnum, Wyo.

Buffalo Creek above North

Fork Buffalo Creek near

Arrointo, Wyo.

North Fork Buffalo Creek

near Arminto, Wyo.

Buffalo Creek below North

Fork Buffalo Creek near

Arminto, Wyo.

Beaver Creek below Bayer

Creek near Barnum, Wyo.

Beaver Creek above White

Panther Ditch near

Barnum, Wyo.

North Fork Powder River

below Pass Creek near

Mayoworth, Wyo.

Powder River near

Kaycee, Wyo.

South Fork Powder River

Drainage

area

(mi2)

697

,379

,253

11.5

45.2

8.80

8.10

18.6

10.9

24.2

100

980

262

Datum of Period

gage above of

NGVD of 1929 record

(ft)

C 2,490 1972-78

2,375.76 1938-42;

1947-78

2,333.3 1922-23;

1928-78

1962-78

C 7,220 1961-78

C 7,660 1974-78

C 7,720 1974-78

C 7,500 1974-78

C 7,030 1974-78

C 5,350 1974-78

C5,700 m!940-78

4,533.76 1933-35;

1938-71

1961-78

Date

5-06-75

6-15-62

6-19-44

6-09-72

6-15-63

6-18-75

6-18-75

6-18-75

8-04-76

6-18-75

8-11-41

"8-11-41

9-11-73

Gage

height

(ft)

12.27

12.33

12.74

16.78

£ 12.60

2.02

2.64

2.16

2.19

2.00

7.64

12.57

8.52

known

Discharge

(ft3/ s )

2,890

13,300

96,300

2,430

7,110

117

201

295

148

222

1,270

5,230

1,200

Day

19

23

22

18

16

16

16

16

16

17

18

__

18

Maxim

Gage

heigh

(ft

11.1

10.1

16.5

4.7

3.6

2.0

2.0

1.9

2.6

2.5

5.2

11.3

8.7

near Powder River, Wyo.
TABLE 3. Summary of flood stages and discharges Continued

Site Permanent

number station 

(fig. 1) number

83

84

85

86

87

88

89

90

91

92

93

06313000

06313020

06313050

06313100

06313180

06313400

06313500

06313700

06316400

06317000

06318500

Drainage

Site of flood- area 

discharge determination (mi2 )

South Fork Powder River 1,150

near Kaycee, Wyo.

Bobcat Creek near 8.29

Edgerton, Wyo.

East Teapot Creek near 5.44

Edgerton, Wyo.

Coal Draw near Midwest, 11.4

Wyo.

Dugout Creek tributary .8

near Midwest, Wyo.

Salt Creek near 769

Sussex, Wyo.

Powder River at Sussex, 3,090

Wyo.

Dead Horse Creek near 151

Buffalo, Wyo.

Crazy Woman Creek at 945

upper station near

Arvada, Wyo.

Powder River at 6,050

Arvada, Wyo.

Clear Creek near 120

Buffalo, Wyo.

Maximum flood 

previously known Maximu

Datum of Period

gage above of 

NGVD of 1929 record 

(ft) Gage Gage 

Date height Discharge Day height 

(ft) (ft3/s ) (ft) 

C4,590 1911; 5-22-62 14.43 35,500 18 i 7.20 

1938-40;

1950-69

1965-78 9-11-73 4.62 1,060 18 1.88 

1965-78 6-10-65 9.92 4,450 18 2.18 

1961-78 6-22-64 13.40 2,620 18 6.93 

C4,930 1965-78 7-15-67 9.10 1,590 18 2.93 

C4,480 1976-78 5-31-76 6.43 3,480 18 9.88 

4,362.95 1938-40; 5-23-52 £ 12.60 32,500 19 15.16 

1950-57;

1977

C 3,970 1958-78 6-22-76 11.32 2,480 18 10.08 

C 3,765 1963-70; 6-15-65 16.02 15,800 20 10.00 

1977

3,622.01 1919-78 9-29-23 i 23.70 k !00,000 20 16.9 

5,184.83 1894; 6-15-63 6.19 3,420 18 3.70 

1896-99;

94

95

06320200 Clear Creek below 322 

Rock Creek near 

Buffalo, Wyo.

06320400 Clear Creek at Ucross, 409 

Wyo.

1917-27; 

1938-78

C4,480 1971-78 5-30-71 6.28 2,060 18 6.00 

C4,070 1976-78 5-11-77 7.46 1,280 19 9.07 
TABLE 3. Summary of flood stages and discharges Continued

Site

number

(fig. 1)

96

97

98

99

100

101

102

103

104

105

106

107

108

Permanent

station

number

06321000

06321100

06321500

06323500

06324000

06324500

06324700

06324710

06324800

06324890

06324900

06324910

06324925

Drainage

Site of flood- area

discharge determination (mi^)

South Piney Creek near 69.4

Story, Wyo.

South Piney Creek below 69.5

Mead-Coffeen Ditch

near Story, Wyo.

North Piney Creek near 36.8

Story, Wyo.

Piney Creek at Ucross, 267

Wyo.

Clear Creek near 1,110

Arvada , Wyo .

Powder River at 8,088

Moorhead, Mont.

Sand Creek near 10.6

Broadus , Mont .

Powder River at 8,748

Broadus, Mont.

Little Powder River .81

tributary near

Gillette, Wyo.

Little Powder River 204

below Corral Creek

near Weston, Wyo.

Cedar Draw near 3.45

Gillette, Wyo.

Cow Creek tributary .72

near Weston, Wyo.

Little Powder River 540

Maximum flood

previously known

Datum of Period

gage above of

NGVD of 1929 record

(ft) Gage

Date height Discharge

(ft) (ft3/8 )

C5,590 x951-78 6-15-63 4.37 2,090

C5,520 1974-78 5-10-77 3.32 524

C5,290 1951-78 6-15-63 5.04 1,820

4,066.83 1917-23; 6-16-63 7.33 3,570

1950-78

3,506.51 1915-19; 8-05-54 10.45 9,600

1928-29;

1939-78

3,334.6 1929-72; P6-17-62 12.77 23,000

1974-78

C 3,090 1955-78 6-09-72 5.39 715

3,016.30 1975-78 P6-24-76 6.19 6,740

1960-78 6-22-64 ^6.44 176

C3,980 1977-78

 1959-78 6-22-64 9.75 758

1971-78 7-02-76 8.17 153

C3,680 1977-78

Maximu

Gage

Day height

(ft)

18 2.97

18 2.73

18 3.04

19 5.30

18 9.03

20 15.24

18 2.12

21 12.96

18 7.97

18 9.61

18 6.87

18 5.93

19 13.32

near Weston, Wyo.
TABLE 3. Summary of flood stages and discharges Continued

Site

number

(fig. 1)

109

110

111

112

113

114

115

116

117

118

119

120

121

122

Permanent

station

number

06324970

06324995

06325400

06325500

06325700

06325950

06326300

06326500

06326510

06364700

06365300

06365900

06375600

06376300

Drainage

Site of flood- area

discharge determination (mi^)

Little Powder River 1,235

above Dry Creek

near Weston, Wyo.

Badger Creek at 6.06

Biddle, Mont.

East Fork Little 3.45

Powder River near

Hammond , Mon t .

Little Powder River 2,039

near Broadus, Mont.

Powder River tributary 3.20

near Powderville,

Mont.

Cut Coulee near 2.23

Mizpah, Mont.

Mizpah Creek near 797

Mizpah, Mont.

Powder River near 13,194

Locate, Mont.

Locate Creek tributary .91

near Locate, Mont.

Antelope Creek near 959

Teckla, Wyo.

Dry Fork Cheyenne River 128

near Bill, Wyo.

Cheyenne River near 1,527

Dull Center, Wyo.

Little Thunder Creek 234

near Hampshire, Wyo.

Black Thunder Creek 535

Maximum flood

previously known

Datum of Period

gage above of

NGVD of 1929 record

(ft) Gage

Date height Discharge

(ft) (ft 3 /s)

C 3,410 1972-78 1-17-74 8.05 1,000

1972-78 6-23-76 7.97 414

1974-78 6-23-76 6.18 155

b3,020 1947-53; 1972 9.30 2,700

1957-61;

1962-72

1973-78 1973 16.91 480

1973-78 5-05-75 8.45 272

C 2,490 1974-78 5-06-75 9.80 1,920

b2,400 1938-78 P2-19-43 11.23 31,000

1973-78 1973 2.41 22

C4,450 1977-78

C5,060 1976-78 

C ' i4,3l2 1976-78 7-08-77 5.50 2,570

C4,400 1977-78

C4,060 1972-78 9-09-73 11.49 804

Maximu

Gage

Day height

(ft)

19 11.62

18 2.48

18 5.69

20 9.85

18 2.42

18 4.17

19 7.04

23 11.27

19 1.40

18 8.83

18 4.01

18 i !2.00

18 9.02

18 14.13

near Hampshire, Wyo.
TABLE 3. Summary of flood stages and discharges Continued

Site

number

(fig. 1)

123

124

125

126

127

128

129

130

Permanent

station

number

06378300

06379600

06382200

06386000

06386500

06387500

06394000

06395000

Site of flooddischarge determination

Lodgepole Creek near

Hampshire, Wyo.

Box Creek near Bill,

Wyo.

Pritchard Draw near

Lance Creek, Wyo.

Lance Creek near

Riverview, Wyo.

Cheyenne River near

Riverview, Wyo.

Turner Creek near

Os age, Wyo.

Beaver Creek near

Newcastle, Wyo.

Cheyenne River at

Edgemont, S. Dak.

Drainage

area

(mi 2 )

354

112

k5.1

2,070

5,270

47.8

1,320

7,143

Maximum flood

previously known

Datum of Period

gage above of

NGVD of 1929 record

(ft) Gage

Date height Discharge

(ft) (ft3/ s )

C 3,950 1977-78

1956-58; 5-05-71 7.92 1,720

1959;

1961-78

1964-78 9-03-68 13.29 4,050

C 3,750 1948-54; 5-24-71 9.67 7,410

1956-78

C 3,600 1948-74 5-22-62 8.74 16,000

1959-78 6-15-62 16.72 3,000

C 3,660 1943-78 6-16-62 19.98 11,900

3,414.56 1903-06; 5-25-71 10.57 13,800

1928-33;

1946-78

Maximu

Gage

Day height

(ft)

18 4.08

18 8.15

18 4.78

19 9.43

12.22

18 15.57

19 16.37

20 13.65

131

132

133

134

135

06425720 Belle Fourche River 495 

below Rattlesnake 

Creek near Piney, 

Wyo.

06425780 Belle Fourche River 594 

above Dry Creek 

near Piney, Wyo.

06425900 Caballo Creek at mouth 260 

near Piney, Wyo.

06425950 Raven Creek near 76.0 

Moorcroft, Wyo.

06426400 Donkey Creek near 246 

Moorcroft, Wyo.

C4,540 1975-78 6-13-77 5.86 489 18 11.33 

C4,460 1975-78 6-13-77 11.81 1,630 18 16.3 

C4,370 1977-78

C4,234 1977-78

C4,200 1977-78

19

19

8.66 

5.55 

19 14.60 
TABLE 3, Summary of flood stages and discharges Continued

Site

number

(fig. 1)

136

137

138

139

140

141

142

143

144

145

146

147

148

Permanent

station

number

06426500

06427500

06427700

06429300

06634300

06634600

06635000

06641400

06642000

06642700

06642760

06643300

06644840

Drainage

Site of flood- area

discharge determination (rai^)

Belle Fourche River 1,670

below Moorcroft,

Wyo.

Belle Fourche River 2,000

below Keyhole

Reservoir, Wyo.

Inyan Kara Creek near 96.5

Upton, Wyo.

Ogden Creek near 8.42

Sundance, Wyo.

Sheep Creek near 174

Medicine Bow, Wyo.

Little Medicine Bow 963

River near Medicine

Bow , Wyo .

Medicine Bow River 2,338

above Seminoe

Reservoir near

Hanna , Wyo .

Bear Springs Creek 9.33

near Alcova, Wyo.

North Platte River at 10,812

Alcova, Wyo.

Lawn Creek near 11.5

Alcova, Wyo.

Stinking Creek near 117

Alcova, Wyo.

Coal Creek near Goose 5.39

Egg, Wyo.

McKenzie Draw tributary 2.02

Datum of Period

gage above of

NGVD of 1929 record

(ft)

4,119.2 1943-70;

1975-78

4,031.26 1951-78

1959-78

1962-78

1961-78

C 6,600 1973-78

6,415.40 1939-78

 1960-78

5,299.40 1904-05;

1934-78

1961-78

1961-78

1960-78

1965-78

Maximum flood 

previously known

Date

5-27-62

9-05-51

7-01-59

5-06-67

7-07-61

4-17-75

3-29-43

10-06-62

6-6, 10

11-1905

8-10-74

8-12-63

6-12-70

9-11-73

Gage

height

(ft)

14.33

6.30

12.99

3.93

11.48

9.05

5.23

12.36

ill. 50

9.15

7.93

8.72

7.03

Discharge

(ft3/s)

r4,420

1,020

4,660

423

1,900

3,060

6,590

533

13,400

1,250

2,750

514

970

Maxim

Gage

Day heigh

(ft)

19 14.6

23 5.8

18 6.3

18 1.7

17 9.7

17 14.1

18 6.25

17 12.24

17

17 7.6

17 7.12

17 6.70

18 1.45

near Casper, Wyo.
TABLE 3. Summary of flood stages and discharges Continued

Site

number

(fig. 1)

149

150

151

152

153

154

155

156

157

158

159

160

Permanent

station

number

06645150

06645160

06646600

06646700

06646780

06646800

06647500

06647890

06647900

06648780

06649000

06649900

Drainage

Site of flood- area

discharge determination (mi 2 )

Smith Creek above Otter 9.91

Creek near Casper, Wyo.

Smith Creek at Otter 10.9

Creek near Casper, Wyo.

Deer Creek below 213

Mi liar Wasteway

at Glenrock, Wyo.

East Fork Dry Creek 2.60

tributary near

Glenrock, Wyo.

Sand Creek near 79.9

Glenrock, Wyo.

North Platte River 13,538

near Glenrock, Wyo.

Box Elder Creek at 63.0

Box Elder, Wyo.

Little Box Elder Creek 7.18

near Careyhurst, Wyo.

Little Box Elder Creek 8.47

at Little Box

Elder Cave near

Careyhurst, Wyo.

Sage Creek tributary 1.38

near Orpha, Wyo.

LaPrele Creek near 135

Douglas, Wyo.

North Platte River 8.53

Datum of

gage above

NGVD of 1929

(ft)

C 6,550

C 6,360

C4,980

 

C 5,000

C4,920

C 6,710

C 5,670

C5,480

_ ._

S 5,600

 

Maximum flood

previously known

Period

of

record

Gage

Date height Discharge

(ft) (ft3/s)

1974-78 5-13-75 3.40 40

1974-78 5-13-75 1.54 39

1961-78 6-12-70 9.45 14,200

1961-78 5-14-65 11.00 550

1977-78 

1959-78 5-14-65 7.10 16,000

1946-51; 5-14-65 ^.58 4,530

1961-67;

1971-78

1974-78 6-18-75 1.31 21

1974-78 9-18-76 1.80 23

1965-78 7-25-65 2.00 229

1919-78 6-12-70 13.01 17,300

1961-78 5-22-61 11.32 1,400

Maximu

Gage

Day height

(ft)

17 1.37

17 2.84

17 8.87

18 6.65

18 3.87

19 4.80

17 6.61

18 1.69

18 2.07

17 .40

17 10.66

18 4.97

161 06651800

tributary near 

Douglas, Wyo.

Sand Creek near Orin, 

Wyo.

27.8 1955; 8-07-55 

1961-78

'20,700 16 C 10.2 
TABLE 3. Summary of flood stages and discharges Continued

Site Permanent

number station

(fig. 1) number

Site of flooddischarge determination

Drainage Datum of Period 

area gage above of 

(mi2 ) NGVD of 1929 record 

(ft)

Maximum flood 

previously known

Gage

Date height Discharge 

(ft) (ft3/ s )

Maximu

Gage 

Day height 

(ft) 

162

163

 Shawnee Creek near ^90 16 

Or in, Wyo.

k!00 8-07-55 7,530

06652000 North Platte River 14,888 C4,660 1895-99; 5-15-65 10.00 23,800 17 7.76 

164

at Orin, Wyo.

06652400 Watkins Draw (formerly 

Watson Draw) near 

Lost Springs, Wyo.

6.95

1917-18;

1924;

1958-78

1960-78 5-28-61 14.78 2,100 16 8.81 

a <, less than;>, greater than.

bAltitude from barometer.

c Altitude from topographic map.

d Estimated.

e Does not include bypass flow of about 9,200 cubic feet per second.

^Mean daily discharge.

^Affected by backwater.

^Less than 10 years of record (Wyoming stations only).

1 Site and datum then in use.

JRevised from Omang and Hull (1978).

^Approximate measurement.

"Peak-flow record prior to 1974 water year includes records for station 06311500 (North Fork River near Mayoworth, Wyo.).

"Flood of Sept. 30, 1923, reached a stage of 18.00 feet (discharge not determined).

PFlood of September 1923 was probably greater.

3Gage moved 125 feet upstream during 1969 (same datum).

r Flood of Apr. 7, 1924, reached a stage of 12.60 feet at site of former gaging station, 4.2 miles upstream at different datum; discha

feet per second. Flood in June 1908 reached a stage about 2.50 feet higher than that of Apr. 7, 1924. 

3Altitude approximate from nearby line of levels. 

^Outside period of record.
52 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

S 8

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TABLE 7. Sediment data Continued

Date

18

24

25

16

19

17

20

17

19

21

17

21

22

23

15

20

15

Time

1700

1205

1200

1430

1200

1215

1635

1015

1530

1330

1000

1500

1730

1350

1120

1400

1600

Temperature

10.0

17.5

17.5

9.0

14.0

14.0

11.0

12.0

15.5

14.5

24.5

14.0

24.5

Suspended sediment Suspended s

Streamflow, Sediment Sediment Fail diameter Sieve diame

instantaneous suspended discharge Percent finer than Percent fin

(ft-Vs) (mg/L) (ton/d) Indicated size, in millimeters Indicated s

0.004 0.016 0.062 0-125 0.250 0.500 1.00- 0.062 0.125 0

06307528 Prairie Dog Creek near Birney, Mont. (Lat 45°17'28" Long 106°40'56")

15 1420 58 100

4.1 93 i.o

3.4 72 .66

06307560 East Trail Creek near Otter, Mont. (Lat 45°04'09" Long 106°24'35")

.25 41 .03

36 454 44

06307600 Hanging Woman Creek near Birney, Mont, (site 58)

8.2 74 1.6

359 566 549 -- 96

06307610 Tongue River below Hanging Woman Creek, near Birney, Mont. (Lat 45°20'19" Long 106°31'28")

1660 134 601 95

06307735 -Home Creek near Ashland, Mont. (Lat 45°32'35" Long 106°11'39")

23 356 22 99

06307740 Otter Creek near Ashland, Mont, (site 62)

390 397 418 95

06307830 Tongue River below Brandenberg Bridge, near Ashland, Mont, (site 64)

1550 510 2130 69

5440 1440 21200 46 68 81 67 

8260 1120 25000 41 61 75 80 

6060 730 11900 42 62 81 88 98 100

06308160 Pumpkin Creek near Loesch, Mont. (Lat 45°42'40" Long 105 0 43'50")

.04 121 .01

146 136 54 99

06308400 Pumpkin Creek near Miles City, Mont, (site 70)

16 146 6.3 -- 99
TABLE 7. Sediment data Continued

Date

16

19

21

23

23

Time

0800

0940

1600

1645

1115

Temperature

17.5

11.5

17.5

18.0

Streamflow, Sediment Sediment 

instantaneous suspended discharge 

(ft3/s ) (mg/L) (ton/d)

1460

6980

4490

7700

96

604

5090

1710

2070

1570

06308500 Tongue

2380

95900

20700

43000

06313400 Salt

407

Suspended sediment Suspended s

Fall diameter Sieve diame

Percent finer than Percent fin

Indicated size, in millimeters Indicated s

0.004 0 .016 0.062 0.125 0.250 0.500 1.00 0.062 0.125 0

River at Miles City, Mont, (site 71)

75

44

30

__

86

61

42

Creek near

66

06313500 Powder River

19

24

1200

1700

9.0

16.0

10500

2530

48500

9560

1380000

65300

06316400 Crazy Woman Creek

19

25

1930

1600

9.0

9.0

1640

1109

2765

2280

12200

6830

31

29

93

at

48

43

_

90

78

Sussex,

94

Sussex,

81

73

at Upper Station,

62

43

06317000 Powder River

19

20

21

19

1305

1435

1415

1340

9.0

13.0

16.5

16400

17800

5050

414

41500

38700

32000

78

1840000

1860000

436000

06318500 Clear

87

39

41

38

76

60

at

57

61

58

Creek near

~

06320200 Clear Creek below Rock

17

19

1300

1440

4.0

8.0

1240

1140

346

241

1160

742

_

86

79

Arvada,

81

83

85

Buffalo

__

95

89

Wyo.

97

Wyo.

95

89

near

92

91

Wyo.

95

94

96

, Wyo.

72

98 100

99 100

54 61 

(site 88)

100

(site 89)

100

99 100

Arvada, Wyo. (site 91)

97 99 100

97 99 100

(site 92)

100

99 100

99 100

. (site 93)

45

Creek near Buffalo, Wyo. (site 94)

_

06320400 Clear Creek at

19

20

21

1545

1830

1640

10.0

10.5

12.0

1410

1090

1190

594

517

477

2260

1520

1530

37 53

__

Ucross,

75

__

Wyo.

86

 _ _ __ __ 

69

(site 95)

91 98 100

57

65

06321500 North Piney Creek near Story, Wyo. (site 98)

19

20

0900

0935

375

290

174

53

176

41

__ __ _- 72

61
TABLE 7. Sediment data Continued

Date Time Temperature

Streamflow, Sediment Sediment 

instantaneous suspended discharge 

(ft3/ s ) (mg/L) (ton/d)

Suspended sediment 

Fall diameter 

Percent finer than 

Indicated size, in millimeters

0.004

19 

20

0750 

0845

1010 

634

06323000 Piney Creek at

225 614 

82 140

Kearny

Suspended 

Sieve diame

Percent fin

Indicated s

0.016 0.062 0.125 0.250 0.500 1.00 0.062 0.125 

, Wyo. (Lat 44°32'08" Long 106°49'18")

06323500 Piney Creek at Ucross,

19

20

21

20

21

18

22

1610

1800

1610

1230

1240

1030

1520

12.0

12.5

12.0

17.0

1090

680

614

3020

2080

6300

8910

217

183

162

1300

1170

19300

22600

639

336

269

06324000 Clear

10600

6570

06324710 Powder

328000

544000

06324890 Little Powder River

16 1430 17.0 10 ,81

49

Creek

34

River

27

45

below

68 84

near Arvada,

54 75

at Broadus,

43 82

69 90

Corral Creek

57 

56

Wyo. (site 99)

90

Wyo.

83

Mont.

96

97

, near

~

97 100

(site 100)

86 92 100

(site 103)

99 100

100

Weston, Wyo. (site 105)

 

58

61

 __ 

56

06324925 Little Powder River near Weston, Wyo. (site 108)

16

19

1000

1030

15.5

10.0

31

4250

400

9130

33

105000 90

 

98 100

__ _ _ 96 

06324970 Little Powder River above Dry Creek near Weston, Wyo. (site 109)

16

22

23

1200

1400

1430

1500

1600

1700

1800

1900

2000

2100

2330

0100

16.5

__

18.0

18.0

17.5

17.5

17.0

103

22600

24100

23000

23600

23500

24000

24100

24700

25200

26600

27200

377

19000

14700

17000

17700

17900

18200

18700

19000

19000

18500

17500

105

06326500 Powder

1160000

957000

1060000

1130000

1140000

1180000

1220000

1270000

1290000

1330000

1290000

River

__

55

near Locate,

 

73 85

Mont.

95

(site 116)

 

100

99

77

81

81

62

84

82

83

83

85

85
TABLE 7. Sediment data Continued

Date Time

Streamflow, Sediment Sediment 

Temperature instantaneous suspended discharge 

(°C) (ftVs) ,(mg/L) (ton/d)

Suspended sediment Suspended s

Fall diameter Sieve diame

Percent finer than Percent fin

Indicated size, in millimeters Indicated s

0.004 0.016 0

22

17

22

0230 

0400 

0600

0900

1145

1615

15 .0

16.0

17.0

21.0

.062 0.125 0.250 0.500 1.00 0.062 0.125 

06326500 Powder River near Locate, Mont, (site 116) Continued

26800 16800 1220000 83 

27000 15300 1120000 86 

25600 15100 1040000 82

06326530 Yellowstone River near Terry, Mont. (Lat 46°48'17" Long 105°17'36")

103000

25

84

5560

06326600 0

160

320

1550000

'Fallen Creek

11

73

48

near

82

90

65

Ismay, Mont.

96

97

79 95 99 100

(Lat 46°25'00" Long 104°46'00")

06326953 Clear Creek near Hoyt, Mont. (Lat 47°00'05"

25

18

1045

1115

14.0

15. 0

4 .9 10

06326995 Upper

.97 9

.13 

Sevenmile Creek near Lindsay, Mont. (Lat 47°

.02

06327850 Glendive Creek near Glendive, Mont

22 1400 31. 0 .20 131 .07

06328000 Deer Creek near Glendive, Mont.

23 1045 19. 0 3 .1 30 .25

06329000 Cottonwood Creek

22 1900 22. 0 .50 68 .09

06329500 Yellowstone River

19

20

21

22

23

24

1700

0700

1700

0700

1700

0630

1700

0630

1145

1700

0510

15.

14.

15.

13.

15.

14.

16.

17.

17.

18.

17.

0

0

0

0

0

5

0

0

0

0

5

33100

43400

57200

72100

78700

85600

91900

99600

103000

108000

103000

8820

7980

9080

7590

6800

4540

5080

4280

3950

3710

5040

788000

935000

1400000

1480000

1440000

1050000

1260000

1150000

1100000

1080000

1400000

near Intake, Mont.

near

54

59

 

. (Lat 47°07'

 

(Lat 47°09'44

Long 104 e 56'31")

 

08 '17" Long 1040 56'40")

16" Long 104°39 '51")

97

" Long 104°42'08")

(Lat 47°14'50" Long 104°18'150")

Sidney, Mont. (Lat 47°40'

72

77

87 96

86 92

42" Long 104°09'22")

90

89

89

87

87

80

83

84

99 100

86

96 98 100
TABLE 7. Sediment data Continued

Dace Time Temperature 

CO

Suspended sedimenC Suspended s

Streamflow, Sediment SedimenC Fall d i ameter sieve diame

instantaneous suspended discharge PercenC finer chan Percent fin

(ft j /s) (mg/L) (ton/d) indicated size, in millimeters Indicated s

0.004 0.016 0.062 0.125 0.250 0.500 1.00 0.062 0.125 

06329500 Yellowscone River near Sidney, MonC. (Lac 47°40'42" Long 104°09'22") Continued

25

25

18

19

15

17

20

19

18

15

18

0900

1220

1700

0630

1700

1230

1300

1350

1700

1530

1430

1045

1750

1630

1500

19.0

19.0

20.0

19.0

20.0

18.0

5.0

9.0

26.0

10.0

12.0

10.0

_

93800

81900

67200

53000

49200

80

870

65

39

2030

178

160

1060

14

2500

5540 1400000 65 86 95 98 100

5590 1240000 58 78 93 98 100

5820 1060000 -- 93

4050 580000 -- -- -- -- ~ 89

3630 482000 -- -- -- 88

06364700 Antelope Creek near Teckla, Wyo. (site 118)

147 32

06365300 Dry Fork of Cheyenne River near Bill, Wyo. (site 119)

15300 35900 83 99 100

8750 1540 95 100

06365900 Cheyenne River near Dull Center, Wyo. (site 120)

317 33 98

8920 48900

06375600 Little Thunder Creek near Hampshire, Wyo. (site 121)

1150 553 89 99 100

06378300 Lodgepole Creek near Hampshire, Wyo. (site 123)

413 178 75 95 100

06425720 Belle Fourche River below Rattlesnake Creek near Piney, Wyo. (site 131)

927 2650 66 81 100

06425780 Belle Fourche River above Dry Creek near Piney, Wyo. (site 132)

42 1.6

3570 24100

18 1900 9.0

25 1915 15.0

1040

2.0

06425900 Carnallo Creek ac MouCh near Piney, Wyo. (sice 133) 

1300 3650 82 95 100

06425950 Raven Creek near Moorcroft, Wyo. (site 134) 

26 .14
TABLE 7. Sediment data Continued 

Date Time

18 1600

20 1430

18 1630

22 1400

Streamflow, Sediment Sediment

Temperature instantaneous suspended discharge 

CO (ft3/ s ) <mg/L) (ton/d)

06426400 Donkey

10.0 2530 2080 14200

11.0 482 708 921

06634600 Little Medicine

5.0 1590 5360 23000

9.5 863 235 548

Suspended sediment Suspended 

Fall diameter Sieve diam

Percent finer than Percent fi

Indicated size, in millimeters Indicated 

0.004 0.016 0.062 0.125 0.250 0.500 1.00 0.062 0.125 

Creek near Moorcroft, Wyo. (site 135)

72 80 86 94 100

49 60 76 91 99 100

Bow River near Medicine Bow, Wyo. (site 141)

39 58 85 96 98 100

83

06635000 Medicine Bow River above Siminoe Reservoir near Hanna, Wyo. (site 142)

19 1400

23 0945

7.0 2220 3770 22600

8.0 1400 1670 6310

44 64 82 86 89 98 100

46 66 89 95 98 100

06646780 Sand Creek near Glenrock, Wyo. (site 153)

17 1445 9.0 .58 1850 2.9 72 99 100
TABLES

TABLE 9. Gage heights and discharges at selected gaging stations 

[ft, feet; ft3/s, cubic feet per second]

59

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06216000. Pryor Creek at

Pryor, Mont, (site 1)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06217750. Fly Creek

Pompeys Pillar, Mont

at

. (site

7) Continued

May 16:

2400 3.55

0600 3.62

1200 3.80

1800 3.99

2400 4.42

No gage-height record

1200 hours on May 23

May 23:

1200 5.08

1800 5.09

2400 5.05

May 24:

0600 4.99

1200 5.08

1800 5.07

2400 5.02

101

106

120

137

187

to

299

301

291

277

299

296

284

06217750. Fly Creek at

Pompeys Pillar, Mont.

7)

(site

(Gage heights estimated on

May 19:

0400

0800

1200

1600

2000

2400

May 20:

0600

1200

1800

2400

May 21:

0600

1000

1400

1800

2400

May 22:

0600

1200

1800 

2400

basis of daily wire-weight

gage readings)

May 17:

2400 5.80

May 18:

0400 6.45

0800 7.60

1000 9.10

1200 11.10

1400 13.10

1600 14.40 1

1800 14.95 2

2000 15.30 4

2400 15.70 7

64

100

187

303

470

682

,160

,610

,270

,380

06267400.

Creek near

(site 12)

May 16:

2400

May 17:

0400

0600

1200

1400

1500

1700

1800

1900

2100

2200

2300

2400

15.90

15.94

15.85

15.65

15.50

15.40

15.30

15.20

15.00

14.45

13.30

11.80

10.18

9.40

8.72

8.25

7.90

7.60 

7.40

East Fork

9,640

10,300

9,020

6,900

5,630

4,900

4,270

3,710

2,800

1,250

716

540

449

324

268

226

196

175 

160

Nowater

Colter, Wyo.

0.82

.82

.98

1.18

1.35

1.59

2.45

3.09

3.32

3.81

3.95

4.18

4.10

0

0

0.39

7.4

26

75

420

754

882

1,180

1,260

1,400

1,350

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06267400. East Fork Nowater

Creek near Colter, Wyo.

(site 12) Continued

May 18:

0300 3.80

0600 3.74

0800 3.66

1200 4.03

1300 4.16

1500 5.37

1700 6.47

2000 6.30

2330 6.65

2400 6.20

No gage-height record

through May 22

1,170

1,130

1,090

1,310

1,390

2,140

2,910

2,790

3,040

2,720

May 19

06270000. Nowood River near

Tensleep, Wyo. (site

May 15:

2400 8.97

May 16:

0600 9.44

1200 9.91

1800 9.78 

2400 9.71

May 17:

0600 9.97

1200 10.46

1500 10.77

1800 10.78

2400 10.85

May 18:

0600 10.97

1200 11.46

1800 12.10

2100 12.41

2400 12.24

15)

1,450

1,630

1,820

1,770 

1,740

1,850

2,080

2,240

2,240

2,280

2,340

2,580

2,900

3,070

2,970
60 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO. 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06270000. 

Tens leap,

Cont inued

May 19:

0600

0900

1100

1500

1800

2400

May 20:

0600

1200

1800

2400

May 21:

0600

1200

1800

2400

06279500.

near Kane

May 16:

2400

May 17: 

0600 

1200 

1800

2400

May 18: 

0600 

1200 

1800

2400

May 19: 

0600 

1200 

1800

2400

Nowood River near 

Wyo. (site 15) 

12.66

12.67

12.94

12.55

12.43

11.88

11.45

11.10

10.97

10.84

10.59

10.16

9.82

9.87

Bighorn

3,220

3,270

3,380

3,200

3,080

2,790

2,580

2,400

2,330

2,270

2,140

1,930

1,790

1,810

River

, Wyo. (site 18)

3.18

3.16 

3.27 

3.86

4.13

5.60 

6.86 

7.48

7.81

8.23 

8.75 

9.06

9.31

3,480

3,440 

3,640 

4,750

5,290

8,480 

11,800 

13,200

14,500

15,700 

17,300 

18,200

18,900

06279500. Bighorn River 

near Kane, Wyo. (site 18) 

Cont inued

May 20

0300

0600

1200

1500

1800

2100

2400

May 21

0600

1200

1800

2400

May 22

0600

1200

1800

2400

9.48

9.55

9.83

9.89

8.91

6.75

6.06

:

5.59

5.18

4.86

4.55

:

4.41

4.37

4.26

4.12

Q629Q5QO. Little

River 

Wyola,

May 16

2400

May 17 

1200

1600

2000

2400

May 18 

0400

0800

1200

1600 

1800 

2000 

2400

19,400

19,800

20,500

20,700

17,400

11,400

9,550

8,350

7,500

6,800

6,150

5,880

5,770

5,550

5,270

Bighorn

below Pass Creek near 

Mont, (site 32)

4.10 

4.40

4.58

5.00

5.61 

6.23

6.81

7.41

8.13 

8.88 

9.24 

9.46

1,090 

1,190

1,270

1,490

1,860 

2,290

2,740

3,300

4,120 

5,280 

6,030 

6,550

06290500. Little Bighorn 

River below Pass Creek near 

Wyola, Mont, (site 32) ~ 

Cont inued

May 19:

0300

0600

1000

1200

1500

1800

2100

2400

May 20:

0400

0800

1200

1600

2000

2400

Q6294QOQ.

River near

(site 35)

May 16:

2400

May 17:

0600

1200 

1800 

2400

May 18:

0600 

1200 

1800 

2400

May 19:

0600 

1200 

1400 

1600 

1800

2000

2200

2245

2400

10.02

9.72

9.41

9.55

9.06

8.75

8.35

7.92

7.41

6.99

6.63

6.30

6.00

5.82

Little

Hardin,

4.08

4.18

4.22 

4.28 

4.47

5.35 

6.35 

7.05 

7.46

7.70 

8.32 

8.63 

9.64 

10.88

11.04

11.08

11.20

11.07

8,010

7,200

6,430

6,770

5,630

5,050

4,400

3,790

3,160

2,740

2,450

2,200

1,980

1,860

Bighorn

Mont.

1,440

1,520

1,560 

1,610 

1,780

2,690 

3,970 

5,010 

5,680

6,150 

7,500 

8,290 

11,700 

19,000

20,500

21,000

22,500

20,900
TABLES 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

61

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height 

(ft)

06294000 Little Bighorn

River near Hardin, Mont.

(site 35) Continued

May 20:

0200

0400

0600

0800

1000

1200

1800

2400

May 21:

0600

1200

1800

2400

May 22:

0600

1200

1800

2400

06294700

Bighorn,

May 16:

2400

May 17:

0600

1200

1800

2400

May 18:

0600

1000

1200

1400

1600

1800

2000

2200

2400

11.03 20,400

10.95 19,600

10.84 18,600

10.70 17,500

10.59 16,600

10.40 15,500

9.91 13,000

9.39 10,700

8.87 9,010

8.47 7,870

8.08 6,930

7.72 6,190

7.20 5,250

6.81 4,640

6.34 3,960

6.00 3,500

Bighorn River at

Mont, (site 39)

3.02 4,090

3.22 4,510

3.45 5,060

3.75 5,780

4.07 6,610

4.45 7,590

5.05 9,210

5.39 10,200

5.78 11,300

6.20 12,500

6.63 13,800

7.14 15,400

7.67 17,300

8.10 18,800

06294700.

Bighorn,

Cont inued

May 19:

0200

0400

0600

0800

1000

1200

1400

1600

1800

2000

2200

2400

May 20:

0200

0400

0600

0800

1000

1200

1400

1600

1800

2000

2200

2400

May 21:

0200

0400

0600

1000

1200

1600

2000

2400

May 22:

0400

0800

1200

1600

2000

2400

Bighorn River at

Mont.

8.50

8.88

9.19

9.43

9.63

9.85

10.16

10.36

10.44

10.86

11.22

11.63

12.45

13.39

13.82

13.94

14.15

14.09

13,89

13.71

13.50

13.22

12.97

12.70

12.40

12.07

11.71

10.58

9.11

7.88

7.40

7.00

6.65

6.37

6.11

5.93

5.71

5.53

(site 39) 

20,200

21,500

22,600

23,500

24,200

25,000

26,200

27,000

27,400

29,600

31,500

34,000

39,600

48,400

54,300

56,200

59,200

58,300

55,300

52,500

49,200

46,200

43,700

41,000

38,400

35,800

33,100

26,200

19,900

15,400

13,900

12,600

11,600

10,700

9,840

9,230

8,480

7,890

06296003. Rosebud

mouth, near Rosebud

(site 45)

May 16:

2400

May 17:

0600

1200

1800

2400

May 18:

0600

1200

1800

2400

May 19:

0600

0700

0800

0900

1000

1100

1130

1200

1300

1400

1500

1600

1800

2400

May 20:

0600

1200

1800

2400

May 21:

0600

1200

1800

2400

2.26

2.35

2.39

2.59

2.80

3.26

3.88

4.44

4.92

4.71

4.67

4.66

4.99

5.54

6.74

6.78

6 TO

. /O

6.77

6.76

6.74

6.69

6.56

6.14

5.76

5.26

4.95

4.73

4.56

4.44

4.32

4.16

Creek at

, Mont.

151

168

176

217

265

393

628

895

1,160

1,040

1,020

1,010

1,210

1,570

2,590

2,620 

2£on , o<:U

2,610

2,600

2,590

2,540

2,420

2,050

1,740

1,380

1,180

1,050

958

895

833

755
62 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO.

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06296003. Rosebud Creek at

mouth, near Rosebud, Mont.

(site 45) Continued

May 22:

0600

1200

1800

2400

06305500.

Sheridan,

May 16:

2400

May 17:

0600

1200

1800

2100

2400

May 18:

0300

0600

1200

1800

2100

2230

2400

May 19:

0600

0900 

1200

1500 

1800 

2400

May 20: 

0600

1200

1800

2400

May 21:

0600

1200

1800

2400

3.97

3.75

3.56

3.43

668

574

498

450

Goose Creek below

Wyo. (site

3.97

4.14

4.49

4.81

5.14

5.71

6.39

7.26

7.39

7.93

8.25

8.33

8.24

7.48

7.05 

6.70

6.36 

6.07 

5.71

5.53

5.31

5.13

5.05

5.02

4.91

4.80

4.96

50)

1,180

1,280

1,490

1,720

1,950

2,370

2,950

3,980

4,140

4,800

5,300

5,430

5,280

4,250

3,730 

3,310

2,900 

2,570 

2,240

2,080

1,880

1,720

1,640

1,620

1,520

1,430

1,560

06305500.

Sheridan,

Cont inued

May 22:

0600

1200

1800

2400

06306100.

Goose Creek below

Wyo. (site 50) 

06306100. Squirrel Creek

near Decker, Mont, (site 51)

--Cont inued

5.04

4.96

4.89

5.02

Squirrel

near Decker, Mont.

May 16:

2400

May 17:

0200

0400

0600

0800

1000

1200

1400

1600

1800

2000

2200

2400

May 18: 

0200

0400

0600

0800 

1000

1200 

1400 

1600 

1800

1900 

2000

2200

2400

2.46

2.69

2.89

2.71

2.67

2.67

2.66

2.67

2.74

2.91

3.16

3.70

4.14

4.44

4.26

4.17

4.65 

5.62

6.82 

6.82 

6.52 

7.02

7.27 

7.04

6.92

6.62

1,640

1,560

1,500

1,620

Creek

(site 51)

16

22

27

22

21

21

21

21

23

28

36

59

84

104

91

85

120 

222

456 

456 

383 

509

584 

515

481

405

May 19:

0200

0400

0600

0800

1000

1200

1400

1600

1800

2000

2200

2400

May 20:

0600

1200

1800

2400

May 21:

0600

1200

1800

2400

06306250.

near Acme,

May 16:

2400

May 17: 

0600 

1200

1800 

2400

6.52

6.62

6.52

6.32

6.19

6.14

6.25

6.30

6.27

6.17

6.04

5.90

5.23

4.80

4.55

4.31

4.14

3.95

3.84

3.75

Prairie Dog

Wyo. (site

2.48

2.55 

2.70

2.84 

3.31

380

403

380

339

313

304

325

335

329

310

287

264

173

132

111

94

83

72

66

61

Creek

52)

69

75 

90

104 

159
TABLES 63

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06306250.

near Acme, 

Continued

May 18:

0200

0400

0600

0800

1000

1200

1400

1600

1800

2000

2100

Prairie Dog Creek

Wyo. (site

3.63

3.94

4.43

4.96

5.45

5.84

6.43

7.03

8.23

9.30

9.51

No gage-height record

0900 hours

May 20:

0900

1200

1400

1600

1800

2000

2200

2400

May 21:

0200

0400

on May 20

9.51

8.90

8.35

7.96

7.66

7.40

7.11

6.86

6.61

6.44

No gage-height record

0900 hours

0900

1200

1800

2400

06306300.

State line

6.05

5.87

5.65

5.46

52) 

199

244

321

415

509

590

721

864

1,180

1,500

1,560

to

1,550

1,370

1,210

1,100

1,020

950

877

816

754

714

to

627

588

542

503

Tongue River at

, near Decker,

Mont, (site 53)

May 16:

2400 6.31 2,520

Time

06306300.

Gage 

height 

(ft)

Discharge 

(ft3/ 8 )

Tongue River at

State line, near Decker, 

Mont, (site 53) Continued

May 17:

0600

1200

1800

2400

May 18:

0400

0800

1200

1400

1600

1800

2000

2200

2400

May 19:

0200

0400

0600

0800

1000

1200

1400

1600

1800

2000

2200

2400

May 20:

0200

0400

0600

0800

1000

1200

1400

1600

1800

2000

2200

2400

6.

6.

6.

7.

7.

8.

9.

9.

10.

10.

11.

11.

12.

12.

13.

13.

14.

14.

14.

14.

13.

13.

13.

12.

12.

11.

11.

10.

10.

10.

10.

9.

9.

9.

9.

8.

8.

39

60

93

35

79

39

22

64

11

64

24

65

00

53

16

73

03

20

25

15

92

54

07

61

11

65

30

97

63

30

00

70

44

22

02

86

68

2

2

3

3

4

5

6

7

8

9

10

11

11

13

14

16

16

17

17

17

16

15

14

13

12

11

10

9

9

8

7

7

6

6

6

5

5

,600

,830

,210

,730

,310

,170

,500

,220

,060

,050

,300

,100

,900

,100

,600

,100

,900

,400

,500

,200

,600

,600

,400

,300

,100

,100

,400

,700

,040

,410

,860

,330

,880

,500

,170

,900

,620

Time

Gage 

height 

(ft)

06306300. Tongue

Discharge 

(ft3/ s )

River at

State line, near Decker, 

Mont, (site 53) Continued

May 21:

0600

1200

1800

2400

May 22:

0600

1200

1800

2400

8.24

8.00

7.80

7.57

7.39

7.44

7.44

7.32

06307500. Tongue

Tongue

Decker,

May 16:

2400

May 17:

0600

1200

1800

2400

May 18:

0600

1200

1800

2400

May 19:

0600

0800

1000

1200

1400

1600

1800

2000

2200

2400

River Dam,

4,

4,

4,

4,

3,

3,

3,

3,

River

near

950

600

320

010

780

840

840

690

at

Mont, (site 56)

13.64

13.64

13.64

14.09

14.10

14.11

14.40

14.61

14.63

14.66

15.16

15.90

16.65

17.32

17.93

18.50

18.96

19.40

19.75

1,

1,

1,

1,

1,

1,

2,

2,

2,

2,

2,

3,

4,

5,

6,

7,

8,

9,

510

510

510

880

890

900

160

360

380

410

930

800

800

800

790

800

660

540

10,300
64 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO. 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Time

Gage 

height 

(ft)

06307500. Tongue

Tongue River Dam,

Discharge 

(ftVs)

River at

near Decker,

Mont, (site 56) Continued

Time

Gage 

height 

(ft)

Q630750Q. Tonjtue

Tongue

Mont.

River Dam,

Discharge 

(ft 3 /s)

River at

near Decker.

(site 56) Continued

Time

06307830

Gage 

height 

(ft)

Tongue

below Brandenberg

near Ashland, Mont

Discharge 

(ft3/s)

River

bridge,

. (site 64)

 Continued

May 20:

0200

0330

0600

0800

1000

1200 

1400 

1600

1800

2000

2200

2400

May 21:

0300

0600

0900

1200

1800

2400

May 22:

0600

1200

1800

2400

May 23:

0600

0900

1000

1200

1400

1500

1600

1700

1800

2400

May 24:

0600

1200

1800

2400

May 25:

19.95

20.00

19.95

19.89

19.80

19.66 

19.49 

19.25

19.07

18.85

18.51

18.43

18.15

17.91

17.68

17.47

17.10

16.81

16.59

16.42

16.27

16.16

16.04

16.01

13.42

13.26

13.45

14.92

16.85

17.17

17.13

16.89

16.70

16.56

16.49

16.43

10,700

10,800

10,700

10,600

10,400

10,100 

9,720 

9,230

8,880

8,450

7,820

7,670

7,170

6,760

6,370

6,030

5,460

5,030

4,720

4,480

4,280

4,130

3,980

3,940

1,350

1,240

1,370

2,680

5,090

5,570

5,500

5,150

4,870

4,670

4,580

4,500

0600

1200

1800

2400

16.38

16.34

16.34

16.31

06307830. Tongue 

below Brandenberg 

near Ashland, Mont

May 17

2400

May 18

0600

1200

1800

2400

May 19

0600

1200

1800

2400

May 20

0600

1200

1800

2400

May 21

0600

1200

1800

2400

May 22

0600

1200

1500

1600

1700

1800

2400

:

5.22

5.30

5.44

5.69

6.05

.

6.44

6.60

6.58

6.57

6.62

6.66

6.89

7.42

.

7.64

7.86

8.19

8.47

;

9.21

9.74

9,95

9.96

9.93

9.91

9.61

4,430

4,370

4,370

4,330

River 

bridge, 

. (site 64)

1,720

1,800

1,940

2,210

2,630

3,120

3,320

3,300

3,290

3,350

3,400

3,700

4,470

4,790

5,100

5,560

5,960

7,140

7,980

8,320

8,340

8,290

8,250

7,770

May 23:

0600

1200

1800

2400

May 24: 

0600 

1200

1800

2400

06309000

at Miles

72)

May 16:

2400

May 17:

0600

1200

1800

2400

May 18:

0600

1200

1800

2400

May 19:

0600

0800

1000

1200

1400

1600

1800

2000

2200

2400

9.23

8.92

8.45

8.01

7.63 

7.38

7.08

6.48

7,170

6,690

5,930

5,310

4,780 

4,410

3,970

3,170

Yellowstone River

City, Mont, (site

5.28

5.44

5.66

5.92

6.63

7.31

8.10

8.47

8.84

9.30

9.68

9.93

10.35

10.77

11.32

11.53

11.86

12.17

12.42

14,400

15,100

16,100

17,400

20,900

24,600

29,300

31,600

34,000

37,100

39,700

41,500

44,600

47,800

52,200

53,900

56,700

59,300

61,500
TABLES 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

65

Time

06309000.

Gage 

height 

(ft)

Discharge 

(ftVs)

Yellows tone River

at Miles City, Mont, (site 

72) Continued

May 20:

0600

1200

1800

2400

May 21 ^

0600

1200

1800

2000

2200

2400

May 22: 

0200

0400 

0600

0800

1000

1200

1400 

1600 

1800

2000 

2200

2400

May 23: 

0600

1200

1800

2400

May 24:

0600

1200

1800

2400

06320200. 

Rock Creek 

Wyo. (site

May 14: 

2400

12.97

13.18

13.37

13.87

14.12

14.44

14.96

15.37

15.59

15.83

16.07

16.29 

16.41

16.50

16.44

16.20

15.57 

14.19 

12.39

11.44 

11.03

10.80

10.23

9.90

9.69

9.57

9.45

9.29

9.13

9.11

Clear 

near 

94)

3.65

66,400

68,300

70,000

74,800

77,200

80,400

85,700

89,900

92,300

94,900

97,500

99,900 

10UOOO

102,300

102,000

98,900

92,100 

77,900 

61,200

53,200 

49,900

48,100

43,700

41,300

39,800

39,000

38,100

37,000

35,900

35,800

Creek below 

Buffalo,

464

Time

06320200.

Gage 

height 

(ft)

Discharge 

(ft 3 /s)

Clear Creek below

Rock Creek near Buffalo, Wyo. 

(site 94) Continued

May 15:

0200

0600

1200

1400

1900

2400

May 16:

0400

0800

1200

1700

2100

2400

May 17: 

0200

0400

0600

0800

1200 

1500 

1800

2100 

2400

May 18: 

0200 

0600

1200

1500

1800

2100

2400

May 19:

0300

0600

1200

1500 

1800 

2100

2400

3.67

3.65

3.58

3.57

4.26

4.76

4.76

4.65

4.50

4.39

4.57

4.93

5.25

5.26

5.44

5.55

5.39 

5.47 

5.59

5.72 

5.84

5.88 

5.74

5.59

5.82

5.95

6.00

5.81

5.63

5.51

5.27

5.22 

5.24 

5.27

5.27

471

464

441

438

683

912

912

862

795

746

826

995

1,160

1,160

1,250

1,320

1,220 

1,270 

1,340

1,420 

1,510

1,540 

1,440

1,340

1,490

1,580

1,620

1,490

1,360

1,290

1,160

1,140 

1,150 

1,160

1,160

Time

Gage 

height 

(ft)

Discharge 

(ftVs)

06320200. Clear Creek below

Rock Creek near Buffalo, Wyo. 

(site 94) Continued

May 20:

0600

1400

1800

2400

06324000

Arvada,

May 15:

2400

May 16:

0600 

1200

1800 

2400

May 17: 

0200

0400

0500 

0600 

0800

1200 

1600

1900

2100 

2200 

2400

May 18:

0300

0700

1500

1800

2100

2230

2400

May 19: 

0200 

0600

1200 

1500

1800

2400

5.10

4.92

5.10

5.39

1,080

990

1,080

1,220

Clear Creek near

Wyo. (site

3.42

3.63 

3.69

3.75 

4.10

4.69

5.44

5.77 

6.20 

6.45

5.72 

5.27

5.14

5.19 

5.33 

5.83

6.44

7.31

7.62

8.41

8.85

9.03

8.93

8.87 

8.71

8.53 

8.22

7.79

7.50

100)

656

748 

777

806 

985

1,300

1,790

2,020 

2,350 

2,540

1,990 

1,670

1,590

1,620 

1,710 

2,070

2,520

3,250

3,560

4,450

4,980

5,210

5,100

5,050 

4,870

4,660 

4,310

3,850

3,560
66 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO. 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Time

06324000.

Gage 

height 

(ft)

Discharge 

(ft3/ s )

Clear Creek near

Arvada, Wyo. (site 100) 

Cont inued

May 20:

0600

1200

1800

2400

May 21:

0600

1200

1500

1600

2000

2400

06324500.

Moorhead,

May 16:

2400

May 17:

0600

1200

1800

2400

May 18:

0200 

0600

1200

7.32

6.73

6.30

6.10

5.91

5.69

5.64

5.64

5.75

5.79

Powder

3,420

2,890

2,540

2,380

2,250

2,090

2,050

2,050

2,130

2,160

River at

Mont, (site 101)

4.12

4.90

6.08

6.42

6.33

7.13 

8.26

9.60

2,110

3,330

5,440

6,120

5,930

7,640 

10,300

13,900

No gage-height record to

1300 hours

May 20:

1300 

1500 

1800 

2000

2100

2115

2200

2300

2400

on May

13.59 

14.03 

14.81 

15.09

15.13

15.24

15.12

15.12

14.90

20

26,700 

28,300 

31,300 

32,400

32,500

33,000

32,500

32,500

31,600

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06324500. Powder River at

Moorhead, Mont. 

 Cone inued

May 21:

0100

0200

0300

0400

0800

1000

1100

14.74

14.09

13.35

12.44

10.17

9.95

9.49

No gage-height

1800 hours

1800

2400

May 22:

0600

1200

1800

2400

May 23:

0600

1200

1800

2400

8.36

7.97

7.88

7.40

7.03

6.98

7.00

6.88

6.71

6.57

(site 101)

29,100

26,700

24,000

21,000

14,100

13,400

12,200

record to

9,320

8,400

8,200

7,130

6,340

6,240

6,280

6,040

5,690

5,420

06324710. Powder River at 

Broadus, Mont, (site 103)

Mav 1 ft '

llajr JL vj 

2400

Mav najf 17- ! 1 

0600 

1200

1800 

2100 

2400

May 18:

0600

1200

1800

2400

4.68

4.86 

4.94

5.93 

6.63 

7.03

7.25

7.96

8.63

9.74

2,800

3,350 

3,470

4,030 

5,230 

5,990

6,440

7,990

9,590

12,700

Time

06324710.

Gage 

height 

(ft)

Powder

Discharge 

(ft3/ s )

River at

Broadus, Mont, (site 103) 

Cont inued

May 19:

0600

1200

1800

2400

May 20:

0600

1200

1800

2400

May 21:

0600

0800

1000

1200

1230

1300

1400

1600

1800

2000

2200

2400

May 22:

0200 

0400

0600

0800

1000

1200

1800

2400

10.61

11.14

11.57

11.77

11.89

11.83

11.85

11.75

12.24

12.50

12.63

12.89

12.96

12.90

12.92

12.76

12.44

11.89

10.98

10.02

9.11 

8.65

8.22

7.92

7.72

7.58

7.34

6.79

06324890. Little 

River below Corral 

near Weston, Wyo.

May 15:

2400 2.04

15,600

17,300

18,800

19,500

20,300

20,000

20,100

19,600

22,900

25,400

26,800

29,300

30,000

29,600

29,700

29,300

28,000

25,300

21,300

17,200

13,300 

11,900

10,700

9,900

9,400

9,050

8,480

7,230

Powder 

Creek 

(site 105)

11
TABLES 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

67

Time

06324890.

Gage 

height 

(ft)

Little

River below Corral

near Western, Wyo.

Discharge 

(ft3/ s )

Powder

Creek

(site

Time

06324925.

near Weston

Gage 

height 

(ft)

Discharge 

(ft 3 /s)

Little Powder River

, Wyo. (site 108)

Time

06324925.

Gage 

height 

(ft)

Little

near Weston, Wyo.

Cont inued

Discharge 

(ft3/ s )

Powder River

(site 108) 

105) Continued

May 16:

0600

1200

1800

2400

May 17:

0600

0900

1800

2100

2200

2400

May 18:

0600

0900

1200

1430

1800

2400

May 19:

0100

0300

0900

1200

1500

1800

2400

May 20:

0300

0700

1500

1900

2100

2200

2400

May 21:

0600

1200

1800

2400

2.01

1.98

1.94

1.98

2.52

3.27

4.19

4.88

5.24

7.04

8.62

8.94

9.40

9.61

9.37

8.92

9.05

9.10

8.56

8.18

7.83

7.54

6.92

6.75

6.55

5.96

5.60

5.47

5.48

5.57

5.00

4.55

4.12

3.89

11

10

9.3

10

24

50

96

140

166

380

1,260

1,570

2,100

2,410

2,060

1,550

1,580

1,740

1,210

922

708

563

353

320

289

221

193

183

184

190

148

118

92

80

May 16:

2400

May 17:

0600

0800

1000

1100

1300

1800

2100

2400

May 18:

0300

0400

0600

0900

1000

1200

1800

2100

2400

May 19:

0045

0600

1200

1500

1800

2400

May 20:

0300

0600

1200

1800

2400

May 21:

0600

0900

1200

1800

2400

2.94

2.96

3.47

3.35

3.68

5.01

6.20

7.32

8.28

8.82

9.08

11.83

13.07

13.13

13.06

11.95

12.99

13.31

13.32

12.47

11.42

11.44

11.16

10.15

9.75

9.46

9.01

8.39

7.68

7.04

6.69

6.47

6.12

5.86

27

28

52

46

64

152

256

439

694

902

1,020

2,860

4,160

4,230

4,150

2,970

4,070

4,440

4,460

3,490

2,500

2,520

2,290

1,570

1,340

1,190

984

733

518

384

322

290

248

222

May 22:

0300

0600

1200

1800

2400

5.57

5.32

4.98

4.69

4.51

06324970. Little

197

176

150

128

115

Powder

River above Dry Creek near

Weston,

May 16:

2400

May 17:

1600

2000

2300

2400

May 18:

0400

0700

0900

1200

1400

1600

2100

2400

May 19:

0300

0530

0730

1200

1600

2400

May 20:

0400

1000

1400

1800

2000

2400

Wyo. (site 109)

4.10

4.17

4.45

4.95

5.67

7.11

8.95

9.51

10.12

10.41

10.47

10.83

11.13

11.54

11.62

11.59

11.44

11.55

10.92

10.42

9.95

9.51

9.00

8.83

8.39

95

104

146

237

382

910

2,100

2,600

3,250

3,600

3,670

4,140

4,560

5,170

5,300

5,250

5,020

5,190

4,270

3,610

3,060

2,600

2,140

2,000

1,670
68 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO. 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Time

06324970

Gage 

height 

(ft)

. Little

Discharge 

(ft 3 /s)

Powder

River above Dry Creek near

Western, Wyo. (site 109)--

Time

06326500.

Gage Discharge 

height (ft3/ s ) 

(ft)

Powder River near

Locate, Mont, (site

Cont inued

116) 

Time

06365300.

River near

Gage 

height 

(ft)

Dry Fork

Bill, Wyo

Discharge 

(ft3/ s )

Cheyenne

. (site

119) Continued

Continued

May 21:

0500

1300

2400

May 22:

0300

1700

2400

06326500

7.91

7.28

6.60

6.46

6.00

5.68

Powder

1,350

995

684

629

468

384

River near

Locate, Mont, (site 116)

May 17:

2400

May 18:

0600 

1200 

1800 

2400

May 19:

0600 

1200

1800

2400

May 20:

0600

1200

1800 

2400

May 21: 

0600

1200

1800

2400

May 22:

0600

1200

1800

2400

4.12

4.24 

4.50 

4.92 

5.49

6.15 

6.50

6.80

7.06

7.41

7.75

8.12 

8.47

8.98

9.35

9.67

9.89

10.28

10.43

10.87

11.19

2,890

3,110 

3,590 

4,430 

5,660

7,350 

8,220

9,000

9,690

10,800

11,800

12,900 

13,900

15,600

16,800

18,100

19,000

20,400

21,200

23,900

26,600

May 23:

0100

0200

0400

0600

0800

1200

1800

2400

May 24:

0600

1200

1800

2400

06365300.

River near 

119)

May 15: 

2400

May 16: 

1800

1830

1900

1930

2200

2400

May 17: 

0500

0900

1330 

1400

2100

2400

11.27

11.22

11.22

11.15

10.92

10.02

8.28

7.66

7.18

6.97

6.83

6.61

Dry Fork

Bill, Wyo 

0.70

.67

2.27

1.89

2.10

1.42

1.62

1.33

1.32

1.45 

1.77

2.3J

2.75

27,400

26,900

26,900

26,200

24,300

19,300

13,500

11,600

10,300

9,720

9,350

8,770

Cheyenne

. (site 

0.80

.70

120

58

89

18

31

14

13

20 

45

133

250

May 18:

0200

0430

0900

1130

1330

1500

1700

1900

2400

May 19:

0700

0900

1500 

2400

May 20: 

0600 

1200 

1800 

2400

06365900. 

near Dull 

120)

May 15:

2400

May 16:

2030 

2200

2230

2300 

2400

3.00

3.88

4.01

4.00

3.82

3.47

3.12

2.93

2.90

2.94

2.23

1.87 

1.58

1.45 

1.37 

1.30 

1.25

348

894

1,010

1,000

846

592

400

318

306

322

112

56 

28

20 

15 

12 

10

Cheyenne River 

Center, Wyo. (site

0.92

.84 

1.40

1.71

3.60 

3.75

38

24 

159

271

1,270 

1,360
TABLES 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

69

Gage Discharge 

Time height 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06365900.

near Dull

Cheyenne River

Center, Wyo. (site

120) Cont inued

May 17:

0130

0230

0330

0600

0730

0900

1400

1530

1800

1900

2100

2200

2300

2400

May 18:

0100

0200

0300

0600

0900

1100

1530

1900

2200

2400

May 19:

0200

0300

0400

0600

0800

1130

1230

1800

2400

May 20:

0600

1200

1700

2400

4.17

3.88

4.84

6.11

5.50

5.15

5.06

4.90

5.17

5.59

6.45

7.75

8.85

10.09

10.77

11.73

12.00

11.66

11.85

11.66

11.44

11.35

10.43

9.76

9.21

8.26

8.04

7.16

6.32

5.60

5.59

4.62

3.68

3.14

2.64

2.25

2.09

1,620

1,430

2,030

2,900

2,460

2,210

2,130

2,030

2,250

2,580

3,290

4,460

5,560

6,910

7,900

10,300

11,800

10,200

11,100

10,200

9,520

9,250

7,540

6,710

6,110

5,150

4,940

4,110

3,380

2,800

2,790

2,070

1,460

1,140

880

695

625

06375600.

Creek near

(site 121)

May 16:

2400

May 17:

0500

0600

0700

0800

0900

1200

1500

1800

2100

2400

May 18:

0300

0600

0900

1200

1300

1315

1800

2400

May 19:

0300

0600

1200

1800

2100

2400

May 20:

0300

0600

0900

1200

1800

2400

May 21:

0300

0600

1200

1800

2400

Little Thunder

Hampshire , Wyo.

06376300. Black Thunder

Creek near Hampshire,

(site 122)

2.17

2.18

5.45

6.48

6.96

6.69

6.12

5.55

5.21

5.02

5.77

6.95

7.90

7.38

6.89

8.10

9.02

8.10

6.98

6.57

6.43

6.56

6.27

5.95

5.45

5.15

4.88

4.72

4.48

4.26

3.97

3.81

3.63

3.42

3.30

3.17

0.40

.50

407

790

1,060

900

629

425

331

285

497

1,050

1,770

1,350

1,010

1,950

3,030

1,950

1,070

836

766

831

693

561

407

316

251

216

183

145

101

82

63

44

35

28

May 16:

2400

May 17:

1400

1430

1500

1600

1900

2400

May 18:

0600

1200

1800

2230

2400

May 19:

0600

1200

1800

2400

May 20:

0600

1400

1800

2400

May 21:

0600

1200

1800

2400

06386000.

Riverview,

May 16:

2400

May 17:

1800

2230

2300

2400

0.67

.69

4.40

7.00

9.05

10.00

10.75

11.50 1

12.25 2

13.11 3

14.13 5

14.12 5

13.51 4

12.72 2

12.00 1

11.21

10.25

8.59

7.40

6.48

5.81

5.31

4.92

4.67

Lance Creek

Wyo. (site

1.40

1.39

1.48

5.15 1

5.75 1

Wyo.

1.0

1.0

226

456

652

746

828

,060

,040

,370

,050

,030

,010

,740

,670

933

760

538

382

268

190

137

99

77

near

126)

30

30

37

,140

,560
70 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO. 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Time

06386000.

Riverview,

Continued

May 18:

0400

0700

0800

0900

1100

1200

1500

1800

2200

2400

May 19:

0500

0600

0630

0730

1230

1530

2400

May 20:

0700

0900

1100

1230

1500

1900

2400

May 21:

0600

1200

1800

2400

May 22:

0600

1200

1800

2400

Gage 

height 

(ft)

Lance

Discharge 

(ft3/ s )

Creek near

Wyo. (site 126) 

6.15

6.70

7.45

8.30

9.03

9.14

9.02

8.73

8.67

8.98

9.42

9.40

9.43

9.33

8.80

8.54

8.17

7.39

6.91

5.92

5.36

4.89

4.41

4.00

3.65

3.36

3.10

2.89

2.76

2.63

2.50

2.40

1,880

2,400

3,240

4,500

6,080

6,350

6,050

5,360

5,240

5,950

7,160

7,100

7,190

6,890

6,120

5,610

4,980

3,780

3,150

2,100

1,630

1,290

1,010

823

684

579

494

433

396

358

325

299

Time

06394000.

Newcastle

May 16:

2400

May 17:

0800

1200

1400

2000

2200

2300

2400

May 18:

0200

0400

0600

0900

1200

1500

1800

2300

2400

May 19:

0100

0600

0800

1000

1300

1800

2000

2200

2400

May 20:

0600

1300

1800

2400

May 21:

0300

0600

1200

1800

2400

Gage 

height 

(ft)

Discharge 

(ft3/s)

Beaver Creek near

, Wyo.

2.33

2.37

2.52

2.45

2.43

2.46

2.62

3.15

5.12

7.54

9.66

11.22

11.97

12.49

12.75

13.08

13.08

13.03

11.89

11.61

11.53

11.65

13.16

15.13

15.85

16.37

15.65

15.10

14.40

13.28

11.37

9.72

7.83

6.40

5.30

(site 129)

26

28

37

33

32

34

45

95

307

636

1,020

1,360

1,540

1,680

1,740

1,830

1,830

1,820

1,520

1,450

1,440

1,460

1,850

2,830

3,420

3,870

3,260

2,800

2,280

1,880

1,390

1,030

684

465

324

Time

06395000.

Gage 

height 

(ft)

Cheyenne

Discharge 

(ft3/ s )

River

near Edgemont, S. Dak. (site

130)

May 16:

2400

May 17:

0600

1200

1800

2400

May 18:

0600

0900

1000

1200

1800

2100

2400

May 19:

0600

1200

1800

2400

May 20:

0600

1200

1800

2100

2^00

May 21:

0300

0600

1200

1800

2400

May 22:

0600

1200

1800

2400

2.58

2.58

2.58

2.57

2.71

2.84

3.96

6.97

8.08

9.34

9.59

10.05

10.34

10.67

11.52

12.68

13.65

13.35

12.45

11.61

10.43

9.20

8.40

7.38

6.37

5.02

4.58

4.34

4.12

4.08

120

120

120

117

157

199

758

3,150

5,020

7,900

8,570

9,510

10,300

11,300

14,100

18,900

28,000

26,500

22,000

18,400

14,300

9,510

8,880

6,790

4,890

2,790

2,230

1,960

1,720

1,680
TABLES 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

71

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06425780. Belle Fourche 

River above Dry Creek near 

Piney, Wyo. (site 132)

May 15:

2400

May 16:

0600

1200

1800

2400

May 17:

0200

0600

1100

1200

1400 

1700

1900

2100

2400

May 18:

0100

0200

0500

0600

0800

1000

1200

1530

1830

1930

2140

2200

2230

2400

3.25

3.23

3.24

3.24

3.33

3.65

3.90

4.10

6.53

7.32 

6.41

5.99

5.92

7.62

8.54

9.11

9.37

11.19

12.81

13.25

13.43

13.16

11.83

11.76

14.68

15.36

16.3

14.90

14

13

14

14

17

32

47

59

264

369 

249

205

198

417

588

718

782

1,380

2,210

2,520

2,660

2,450

1,640

1,610

3,800

4,530

5,630

4,020

No gage-height record May 19

through May 21

06425900. Cabal lo

mouth near Piney,

133)

May 15:

2400 2.10

Creek at

Wyo. (site

1.0

06425900. Cabal lo Creek at 

mouth near Piney, Wyo. (site 

133) Continued

May 16:

0600

1200

1800

2200

2400

May 17:

0100

0200

0300

0430

0600

1200

1800 

1900

2000

2100

2200

2300

2400

May 18:

0200

0500

0700

0900

1100

1300

1500

1700

1800

2100

2400

May 19:

0600

0915

1200

1500

1800

2100

2400

2.08

2.07

2.06

2.06

2.33

2.41

3.50

3.40

3.54

3.09

2.49

2.40 

2.46

2.66

3.18

3.94

4.77

5.20

5.82

4.83

5.86

6.18

6.66

7.14

6.73

7.33

7.22

7.62

8.01

8.39

8.66

8.12

7.73

7.46

6.83

6.53

.90

.80

.70

.70

3.1

4.5

42

37

45

23

6.1

4.3 

5.4

12

27

75

178

260

422

190

435

545

748

996

781

1,100

1,040

1,290

1,560

1,890

2,170

1,650

1,360

1,180

831

688

06425900. Cabal lo Creek at 

mouth near Piney, Wyo. (site 

133) Continued

May 20:

0300

0600

1200

1800

2400

May 21:

0600

1200

1800

2400

06426400. 

Moorcrof t

May 16:

2400

May 17:

0400

0515

0600

0700

2100

2200

2400

May 18:

0600

1000

1200

1500

2400

May 19:

0300

0545

0900

1200

1500

1700

1800

2100

2400

6.07

5.81

5.38

5.07

4.82

4.53

4.37

4.24

4.11

505

419

303

236

188

144

123

108

94

Donkey Creek near 

, Wyo. (site 135)

1.60

1.56

4.03

3.24

2.54

2.45

2.59

3.70

7.05

9.80 1

12.24 2

13.39 2

13.90 2

14.55 3

14.60 3

14.44 3

13.49 2

11.95 1

11.04 1

10.68 1

9.79 1

9.14 1

3.2

2.4

154

86

35

30

38

123

559

,220

,060

,550

,840

,820

,950

,550

,590

,950

,620

,490

,210

,030
72 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO. 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Gage 

Time height 

(ft)

06426400. Donkey

Discharge 

(ft3/ s )

Creek near

Moorcroft, Wyo. (site 135) 

Continued

May 20:

0100 8.97

0600 6.77

0700 7.80

1200 6.77

2400 5.31

May 21:

0300 5.08

0600 4.90

1200 4.59

1800 4.33

2400 4.15

May 22: 

0600 3.97

1200 3.82

1800 3.52

2400 3.26

06426500. Belle

980

514

700

514

306

277

254

216

186

167 

148

134

10887'

Fourche

River below Moorcroft. Wvo.

(site 136)

No gage -height record May 17

to 2400 hours on

May 18:

2400 14.41

May 19:

0300 14.60

0600 14.39

1100 14.05

1600 13.73

2200 13.64

2400 13.47

May 20:

0700 12.99

1400 12.53

2200 11.94

2400 11.83

May 18

13,400

15,300

13,200

10,200

7,780

7,200

6,300

4,500

3,350

2,350

2,200

Time

06426500.

Gage Discharge 

height (ftVs) 

(ft)

Belle Fourche

River below Moorcroft, Wyo. 

(site 136) Continued

May 21:

0800

1200

1500

1900

2400

May 22:

0400

1000

1800

2400

11.32

11.08

10.76

10.15

9.19

8.50

7.69

6.96

6.45

06635000. Medicine 

River above Seminoe 

Reservoir near Hanna

(site 142)

May 16:

2400

May 17:

1200

1500

1800

2100

2400

May 18:

0600

1230

1800

2400

May 19:

0600

1200

1800

2400

May 20:

0600

1200

1800

2400

2.20

2.22

2.38

3.44

4.43

4.95

6.00

6.25

5.08

4.18

4.04

4.02

4.18

4.11

3.91

3.72

3.70

3.82

1,670

1,510

1,340

l.,110

845

692

545

444

381

Bow 

, Wyo.

590

604

716

1,590

2,720

3,380

4,720

5,220

3,540

2,420

2,250

2,220

2,420

2,330

2,100

1,890

1,870

2,000

Gage Discharge 

Time height (ft 3/s) 

(ft)

06635000. Medicine Bow

River above Seminoe 

Reservoir near Hanna, Wyo. 

(site 142) Continued

May 21:

0600

1200

1800

2400

May 22:

0600

1200

1800

2400

3.77

3.66

3.48

3.37

3.34

3.33

3.24

3.13

06646600. Deer 

Millar Wasteway 

Wyo. (site 151)

May 15:

2400

Mav may 1 x ft u ' »

0600

1000

1300

1400

1800

2200

2400

May 17:

0330

0430

0600

0700

0730

0800

0830

1000

1130

1400

1800

2100

2400

5.00

5.09

5.11

4.89

4.84

4.82

4.85

4.93

5.29

5.75

7.70

8.57

8.74

8.71

8.84

8.75

8.61

7.89

7.24

7.03

7.08

1,950

1,830

1,630

1,520

1,500

1,490

1,410

1,310

Creek below 

at Glenrock,

340

385

396

290

268

259

272

308

494

775

2,620

4,650

6,090

5,755

5,560

5,000

4,650

3,030

2,330

2,110

2,160
TABLES 73

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Time

06646600.

Gage Discharge 

height (ft 3/s) 

(ft)

Deer Creek below

Millar Wasteway at Glenrock, 

Wyo. (site 151) Continued

May 18:

0030

1000

1700

2000

2400

May 19:

0200

0700

1400

1700

2400

May 20:

0400

1000

1900

2400

May 21:

0600

1200

1800

2400

06646780. 

Glenrock,

May 16:

2400

Mav i id j 17" i. / 

1200 

1600

1700

1800

1900 

2200

2300

2400

7.11

6.69

6.24

6.23

6.37

6.36

5.96

5.67

5.61

5.87

5.79

5.49

5.28

5.31

5.27

5.17

5.10

5.05

2,190

1,770

1,380

1,370

1,490

1,480

1,170

972

936

1,110

1,050

864

739

756

734

678

640

615

Sand Creek near 

Wyo. (site 153)

1.66

1.68 

1.76

1.95

2.46

2.37 

2.68

2.53

2.78

0.40

.60 

1.6

10

60

48 

96

70

113

Gage Discharge 

Time height (ft 3 /s) 

(ft)

06646780. Sand Creek

Glenrock, Wyo. (site 

Continued

May 18:

0300

0600

0900

0930

1300

1600

1700

1900

2000

2400

May 19:

0100

0200

0300

0600

0900

1200

1500

2400

May 20:

0500

1200

1500

1800 

2400

May 21:

0600

1200

1500

1800 

2400

06646800.

River near 

(site 154)

May 16:

2400

3.61

3.51

3.76

3.87

3.27

2.73

2.84

3.51

3.71

3.25

2.96

2.80

2.62

2.43

2.19

2.00

1.80

1.77

1.77

1.74

1.75

1.72 

1.72

1.73

1.73

1.75

1.74 

1.74

near

153) 

344

308

407

460

232

103

125

308

385

227

151

117

83

54

27

8.0

2.6

1.8

1.8

1.2

1.4

1.0 

1.0

1.0

1.0

1.2

1.1 

1.1

North Platte

Glenrock,

2.19

Wyo.

1,290

Time

Gage Discharge 

height (ft 3 /s) 

(ft)

06646800. North Platte

River 

(site

May 17

0600

0900

1200

1300

1800

1900

2000

2100

2200

2400

May 18

0600

1200

1800

1900

2000

2400

May 19

0100

0600

1000

1200

1330

1800 

2400

May 20

0200

0600

1200

1800 

2400

May 21 

0600

1200 

1800

2400

near Glenrock, 

154) Continued

2.31

3.17

4.51

4.71

3.73

3.14

3.90

3.80

3.55

3.52

:

3.80

4.12

4.16

4.19

4.35

4.52

:

4.48

4.61

4.59

4.72

4.80

4.65 

4.60

4.43

4.36

4.03

3.81 

3.78

3.60

3.42 

3.60

3.92

Wyo.

1,430

2,740

5,660

6,190

3,820

2,680

4,190

3,970

3,460

3,400

3,970

4,700

4,790

4,860

5,250

5,680

5,580

5,920

5,870

6,220

6,440

6,030 

5,890

5,450

5,280

4,490

4,000 

3,930

3,560

3,200 

3,560

4,240
74 MAY 1978 FLOODS, SOUTHEASTERN MONT. AND NORTHEASTERN WYO. 

TABLE 9. Gage heights and discharges at selected gaging stations Continued

Time

06647500.

Gage 

height 

(ft)

Discharge 

(ft3/s )

Box Elder Creek

at Box Elder, Wyo.

May 15:

2400

May 16:

0300

0600

1200

1500

1800

2130

2200

2300

2400

May 17:

0100

0330

0600

0900

1400

2000

2400

May 18:

0600

1200

1500

1730

2400

May 19:

0300

0600

1200

1500

1800

2400

May 20:

0600

1200

1500

1800

2100

2400

3.96

3.99

3.94

3.88

3.86

3.92

4.34

4.37

4.53

5.04

5.37

6.61

6.28

5.85

5.54

5.42

5.30

5.10

4.90

4.89

4.93

4.70

4.60

4.54

4.44

4.43

4.44

4.37

4.27

4.18

4.15

4.18

4.22

4.18

(site 155)

424

436

416

392

384

408

580

595

675

964

1,180

2,230

1,910

1,540

1,300

1,210

1,130

1,000

880

874

898

760

710

680

630

625

630

595

548

512

500

512

528

512

Time

06649000.

Gage 

height 

(ft)

LaPrele

near Douglas, Wyo.

May 15:

2400

May 16:

0400

1200

1400

2000

2400

May 17:

0300

0600

0700

0900

1200

1800

2400

May 18:

0600

1200

1500

2400

May 19:

0600

1200

1800

2400

May 20:

0600

1200

1800

2400

May 21:

0600

1200

1400

1600

1800

1830

2100

2400

7.06

7.28

6.98

6.62

6.68

7.40

8.85

10.59

10.66

10.62

10.31

10.06

10.52

10.57

10.29

9.96

9.77

9.13

8.72

8.36

8.24

8.07

7.88

7.58

7.58

7.50

7.32

7.27

7.50

8.14

8.36

8.05

7.85

Discharge 

(ft 3 /s)

Creek

(site 159)

317

345

305

257

265

364

582

1,530

1,700

1,610

1,080

848

1,410

1,510

1,050

802

748

627

561

504

486

459

431

387

387

376

350

343

376

469

504

456

427

Time

06652000

River at

163)

May 15:

2400

May 16:

0600

1200

1800

2000

2100

2200

2300

2400

May 17:

0100

0230

0400

0500

0600

0800

1000

1200

1400

1500

1800

2000

2100

2200

2400

May 18:

0200

0300

0400

0600

0900

1200

1800

2000

2400

May 19:

0400

0800

1200

1400

2100

2400

May 20:

0300

0600

1200

1500

1800

2100

2400

May 21:

0600

1200

1800

2400

Gage 

height 

(ft)

Discharge 

(ft3/s )

. North Platte

Orin, Wyo

3.90

3.86

3.82

3.75

4.01

4.91

6.32

7.11

6.80

6.76

7.76

6.77

6.07

5.56

4.89

4.70

4.58

4.42

4.42

4.47

4.67

4.96

5.48

6.56

7.01

7.09

7.09

7.03

6.79

6.66

6.51

6.59

6.63

6.53

6.41

6.57

6.60

6.56

6.44

6.37

6.32

6.25

6.16

6.03

5.88

5.66

5.36

5.24

5.13

4.94

. (site

2,460

2,440

2,380

2,270

2,690

4,400

7,790

10,100

9,130

9,100

12,200

9,130

7,200

5,930

4,420

4,030

3,790

3,480

3,480

3,580

3,970

4,570

5,740

8,530

9,930

10,200

10,200

9,990

9,280

8,900

8,480

8,700

8,820

8,620

8,280

8,730

8,820

8,700

8,360

8,250

8,120

7,920

7,680

7,340

6,950

6,390

5,740

5,460

5,210

4,780