UNITED STATES DEPARTMENT OF THE INTERIOR 

J. A. Erng, Secretary

GEOLOGICAL SURVEY 

W. E. Wrather, Director"

Water-Supply Paper 1048

A 

/ ' '

DISCHARGE AND SEDIMENT LOADS IN THE 

BOISE RIVER DRAINAGE BASIN, IDAHO

1939-40

BY

S. K. LOVE AND P.-C. BENEDICT

Prepared in cooperation with the

FLOOD CONTROL COORDINATING COMMITTEE 

UNITED STATES DEPARTMENT OF AGRICULTURE

****** *** ** «ffic»|

IWfcAWFUt u*. Vol. Z, n. 860, See

UNITED STATES

GOVERNMENT PRINTING OFFICE 

WASHINGTON : 1948

For sale by the Superintendent of Documents, U. S. Government Printing Office, Washington 25, D. C.

Price 65 cents
CONTENTS

Page

Abstract_________________________________^____-___-______-___,_ 1

Introduction. _____________________________________________________ 2

Boise River drainage basin__________________________________________ 3

Geography ^ __________________ _______________________ 3

Topography and drainage___._____________________--____-______ 4

Climate-________----_---__-__-_______--_-_------_----------_- 5

Stream gradients--______-_____________----___--__-____---__-_- 11

Reservoirs------_---_--_--_---_-_-- 7 -------------------------- 11

Irrigated areas ________________________________________________ 12

Placer-mining areas.___________________________________________ 12

Areas selected for runoff and sediment-load measurements ______ 14

Runoff____--__-______________-__.__-______________-_ _ 14

Measurement of runoff__-_-_--_-_-----_-__----_---_---_-_ ___ 14

Comparison of runoff___-________________--__l__ _ _____________ 16

Diversions from the Boise"River_________________________________ 19

Sediment loads._____________________________________v_--__-_____-_ 19

Definition of terms.___________________________________________ 19

Collection of sediment samples._________________________________ 20

Sampling equipment_-__---______--_------_____---------__- 20

Sampling procedure______________________________________ 22

Sampling frequency--_-__-_i____-___--___-----_-----_-_-_-_- 23

Laboratory procedure._________________________________________ 24

^ Determination of sediment concentration of samples.___________ 24

Determination of size composition of samples _________________ 24

Computation of sediment loads____'____________________________ 25

Basis of reporting sediment loads._________-___--___-__-__--___-- 27

Reliability of reported sediment loads:__________________-________ 28

Sediment loads measured in streams near Idaho City.____________ 30

Sediment loads measured above and below Arrow Rock Dam_______ 35

Sediment loads measured at 13 stations during spring runoff of 1939

.and 1940________________________________________________ 37

Sediment loads measured at 13 stations during 18-month period of

investigation. _______________________________________________ 42

Variations in sediment concentration and stream velocity in the New York

Canal._..__________________________________________________ '43

Bed load_____________'____,:____________________________________ 54

Bed load in the New York Canal_________._____________________- 54

Bed load in streams in other parts of the Boise River drainage basin__ 61

Deposited sediments_______________________________________________ 62

Weight-volume relation of deposited sediments____________________ 62

Size composition of deposited sediments__________________________ 64

Specific gravity of samples of deposited sediments _________________ 64

Source of sediment deposited above Diversion Dam________________ 66

in
IV CONTENTS

	Page

Sluicing of Arrow .Rock Reservoir_________________________________ 69

Variations in channel cross sections in the vieinity of gaging stations ____ 71

Daily discharge and sediment loads______________________ 76

Station descriptions________________________________.____ 76

Size analyses of sediments.__________________________!______________ 114

Composition of dissolved matter in the Boise River.______^_____ _______ 144

Index ____________________________ 149

ILLUSTRATIONS

Pag« 

PLATE 1. Map of the Boise River drainage basin______.___________ 10

2. Arrow Rock Dam on.Boise River at Arrow Rock, Idaho_____ 18

3. A, Cottonwood Creek at-Arrow Rock Reservoir; B, Elk Creek

above Gold Hill placer diversion_.____________________ 18

4. Pine Creek above Barry placer diversion__________________ 26

5. Tait-Binckley sampler: A, In open position; B, in closed

position____________________________________________ 26

6. A, Horizontal sampler for collecting integrated samples from 

footbridge; B, sampler used for collecting integrated samples 

from overfall section_____.-___-_________-_--___-_______ 34

7. A, Dredge tailings from placer mining on Moore Creek below 

Idaho City; B, shallow outlet from deep pool in placered 

area on Moore Creek below Idaho City__________________ 34

8. Sediment concentration and velocity in New York Canal during

spring runoff of 1940.--------------------------------- 44

9. A, Coarse sediment in New York Canal, 18.6 miles below Diversion Dam; B, fine sediment deposited in farm lateral ditch 

opposite gate in New York Canal, 18.4 miles below Diversion 

Dam______!___.__________________-______ 68

10. A, Arrow Rock Reservoir at mouth of Cottonwood Creek; B, 

Alternate layers of fine, mud and coarse sand deposited at 

mouth of Cottonwood Creek.______________^___________ 68

11. A, Debris cone at mouth of side canyon entering Grouse Creek 

1 mile above gaging station; B, sediment and debris deposited 

at mouth of Grouse Creek exposed by drawdown in Arrow 

Rock Reservoir________-------_-__---_---------------- ' 74

12. Boise River at Diversion Dam: A, View upstream showing 

sediment deposited behind dam; B, view downstream showing dam and head gates at intake of New York Canal _ _____ 74

FIGURE 1. Cumulative precipitation at Idaho City for 3-year period

ended September 30, 1940, and the normal for 35 years____ 6

2. Cumulative precipitation at Arrow Rock for 3-year period

ended September 30, 1940, and normal for 28 years_.____ 7

3. Cumulative precipitation at Boise for 3-year period ended

September 30, 1940, and normal for 77 years.____________ 7

4. Mean.monthly temperatures at Idaho City for 3-year period^

euded September 30, 1940, and normal for 35 years. ______ 8
CONTENTS

5. Mean monthly temperatip-es at Arrow Rock for 3-year period

ended September 30, 1940, and normal for 28 years- ______ 8

6. Mean monthly temperatures at Boise for 3-year period ended

September 30, 1940, and normal for 77 years. ________ _ _ 9

7. Maximum discharge of the Boise River near Twin Springs and 

Moore Creek near Arrow Rock for years ended September 

30, 1939 and 1940. _ _____________ __ __________ ____ 17

8. Mean discharge of the }3oise River near Twin Springs and 

Moore Creek near Arrpw Rock for years ended September 

1939 and 1940 _ ____^______ _ ___ __ ___________ ___ 17

9. Discharge, sediment concentrations, and sediment loads 

measured in Moore Crejek above Thorn Creek, March 26-27, 

1940___ __ __-____ _-_----___ _ _____________ ___ 26

10. Discharge, sediment . concentrations, and sedime'nt loads 

measured in Granite Creek near Idaho City, March 26-27, 

1940_ _______________________________________________ 27

11. Size analyses of sediment! carried past five gaging stations near

Idaho City during spring runoff of 1939 ___ _____ _ 32

12. Size analyses of sediment carried" past five gaging stati6ns

near Idaho City during 'spring runoff of 1940_ ______ _ ___ 33

13. Size analyses of sediment carried by Boise River near Twin 

Springs and by Cottonwood Creek during spring runoff of 

1940_.___._ _________ _ __________________ 38

14. Size analyses of sediment carried by Cottonwood Gulch and by

Grouse Creek during spring runoff of 1939 _ _ ____________ 39

15. Size analyses of sedimenlj carried by New York Canal during

spring runoff of 1939__U______ _ __ __ _ __ _ _____ 40

16. Size analyses of sediment carried by New York Canal during

spring runoff of 1940 __ ___________^____.______________ 41

17. Variation of sediment concentration with depth in New- York

Canal at different times; during spring runoff of 1940_ .» _ _ _ _ 44

18. Size analyses of sediment carried at varying depths in New

' York Canal, April 20, 1940__________ __ ____ _ ______ _ 52

19. Size analyses of sediment carried at varying depths in, New

York Canal, May 1,' 1940 __ _ _____ _ __________ 53

20. Sediment concentrations in bottom samples from New York

Canal, June 19, 1940_______.___________. ___ ________ 59

21. .Size analyses of depositedlsediment from several streams in the

Boise River drainage basin_______________l_____________ 65

22. Size analyses of deposited sediment from Moore Creek between

Grimes Creek and Boise River __ ______________________ 67

23. Size analyses of deposited sediment from Boise River above

Diversion Dam_________. _____________________ __ _. _ , 68
DISCHARGE AND'SEDIMENT LOADS IN THE BOISE 

RIVER DRAINAGE BASIN, IDAHO 1939-40

By S. K. LOVE and P. C. BENEDICT

* ABSTRACT

The Boise River project is a highly developed agricultural area comprising some 

520 square miles of valley and bench lands in southwestern Idaho. Water for 

irrigation is obtained from the Boise River and its tributaries which are regulated 

by storage in Arrow Rock and Deer Flat reservoirs. Distribution of water to the 

farms is effected by 27 principal canals and several small farm laterals which1 

divert directly from the river. The- New York Canal, which is the largest, not 

only supplies water to smaller canals and farm laterals, but also is used to fill 

Deer Flat Reservoir near Nampa from which water is furnished to farms in the 

lower valley. During the past 15 years maintenance costs in a number of those 

canals have increased due to deposition of sediment in them and in the river 

channel itself below the mouth of Moore Creek.

Interest in determining the runoff and sediment loads from certain areas in the 

Boise River drainage basin led to an investigation by the Flood Control Coordinating Committee of the Department of Agriculture. Measurements of daily 

discharge and sediments loads were made by the Geological Surv3y at 13 stations 

in the drainage basin during the 18-month period ended June 30, 1940. The 

stations were on streams in areas having different kinds of vegetative cover and 

subjected to different kinds of land-use practice. Data obtained during the investigation furnish a basis for certain comparisons of runoff and sediment loads 

from several areas arid for several periods of time.

Runoff measured at stations on the. Boise River near Twin Springs and on 

Moore Creek near Arrow Rock was smaller during 1939 than during 1940 and was 

below the average annual runoff fQr the period of available record. Runoff 

measured at the other stations on the project also was smaller during 1939 than 

during 1940 and probably did not exceed the average for the previous 25 years.

The sediment loads measured during the spring runoff in 1939 were smaller 

at most stations than those measured during the spring runoff in 1940. At those 

stations where the flow was not affected, or only slightly affected, by upstream 

diversions or by placer-mining operations, the largest sadiment loads per unit of 

drainage area were measured in Grouse Creek during both 1939 and 1940, amounting to 3,460 and 2,490 tons per square mile, respectively, and the smallest loads 

per unit of drainage area were measured in Bannock Creek during 1939 and in the 

Boise River near Twin Springs during 1940, amounting to 14 and 83 tons per 

square mile, respectively.

Size anaylses of a large number of samples of suspended and deposited

sediments give an indication of the origin of sediments carried past some of the

stations. The analyses show that most of the sediment measured at the five 

stations in the Moore Creek drainages basin above Idaho City consisted largely of 

coarse material. They show, also, that the sediment measured at th'e station on 

Moore Creek above Thorn Creek consisted almost entirely of fine material during
2 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

practically the entire period of the investigation. Most of the coarse material passing the stations above Idaho City probably was retained behind the dikes or in 

the pools usually formed by tailings from dredging operations in the placer-mining 

area below Idaho City, and much of the fine material measured at the station 

on Moore Creek above Thorn Creek probably was contributed by placer-mining 

activity. During the years when the spring runoff is greater than that measured 

during 1939 and 1940, it is probable that the dikes and pools will be less effective 

in retaining coarse sediments within the placered area.

Records of sediment loads measured in the New York Canal indicate that a 

negligible amount of sediment was deposited ..there during 1939, but that in 1940 

from 10 to 15 percent of the total load at the gaging station cpnsisted of coarse 

sediment which was later deposited on the canal bottom. Most of the fine material 

was doubtless carried through the canal and eventually deposited in diversion 

ditches and on farm land. Because the sediment carried past the station on Moore 

Creek above Thorn Creek consisted almost entirely of fine material, it is probable, 

that a considerable part of the coarse sediment carried in the New York Canal 

during the 1940 spring runoff period was scoured from the large bed of deposited 

material in the Boise River above Diversion- Dam", and that the remainder came 

from Grimes Creek. Arrow Rock Reservoir was not sluiced during the investigation, and it is therefore unlikely that any of the coarse sediment in the New York 

Canal came from the Boise River above Moore Creek during 1939 and 1940.

The average dry weight of 71 samples of deposited sediments collected from 

several parts of the Boise River drainage basin is about 90 pounds per cubic 

foot. The average specific gravity of 77 samples of deposited sediments is 2.57.

INTRODUCTION

During the 18-month period ended June 30, 1940, under a cooperative arrangement with the Flood Control Coordinating Committee'of 

the Department of Agriculture, the Geological Survey measured runoff and sediment loads at 13 stations on streams in the Boise River 

drainage basin in Idaho. The project was initiated by the Flood Control Coordinating Committee for the purpose of determining the runoff and sediment loads of certain streams in areas having different kinds 

of vegetative cover and subjected to different kinds of land-use 

practice. . :

Field work was performed by personnel of the Geological Survey 

under the direction of T. R. Newell, district engineer, Boise, Idaho, who 

served as the local representative of the Geological Survey. The construction of gaging stations, the measurements of discharge and channel cross sections, and general field operations were under the immediate supervision of P. C. Benedict, engineer. He was assisted in the 

construction of the gaging stations by J. R. Throckmorton, engineer, 

and in general field measurements and operations by E. J. Rusho and 

H. L. Walpole, 'engineers. The development of sediment-sampling 

equipmentj the collecting of sediment samples and their analysis in the 

laboratory, and the computation of sediment loads were under the 

direction of S. K. Love, chemist. He was assisted in the laboratory
BOISE EIVER DRAINAGE BASIN 3

*

analysis 6f samples by H. A. Swenson, chemist. The collecting of 

sediment samples was done mostly by local help.

Acknowledgements are made to officials of the several interested 

agencies for their cooperation and assistance during the investigation. 

Among those who helped plan the work or who furnished information 

are T. H. Van Meter, project leader, Boise Watershed Survey, who 

served as the representative of the cooperating agencies of the Department of Agriculture; Guy B. Mains, supervisor, Boise National Forest; 

W. H. Tuller, manager, Board of Control, Boise Project; R. J. Newell, 

construction engineer, United States Bureau of Reclamation; W. E. 

Welsh,' watermaster, Boise River; Franklin Girard, Idaho State 

kforester; and the county commissioners of Boise County.

Records collected from the beginning of the investigation to September 30, 1939, are given in two progress reports issued in mimeographed form under the title, "Discharge and silt loads in the Boise 

River drainage basin, Idaho," The first progress report, issued in 

November 1939, showed results for the 6-month period ended June 

30, 1939, and the second issued in April 1940, covered the 3-month 

period ended September 30, 1939.

A third report, also mimeographed, was issued in December 1940 

under the title, "Discharge and sediment loads in the Boise River 

drainage basin, Idaho, 1939-40." It contained a brief description of 

the general features of the Boise River drainage basin and a discussion 

both of the methods used in the investigation and of the problems 

involved in the measurement of runoff and sediment loads. It also 

contained records collected between October 1, 1939, and June 30, 

1940, and summarized results for the entire 18-month period.

The present report includes all the basic data given in the mimeographed reports, detailed results of size, analyses of sediments most 

of which were not given in the earlier reports, and other data no.t 

previously released. The records of daily discharge obtained during 

the investigation also are published in Geological Survey WaterSupply Papers 883 and 903.

BOISE RIVER DRAINAGE BASIN

GEOGRAPHY

The drainage basin of B'oise River is in southwestern Idaho and 

comprises parts of Camas, Elmore, Boise, Ada, Canyon, Gem, and 

Payette Counties. It is about 115 miles in length and 60 miles in 

maximum width, and has an area of about 4,130 square miles. Boise, 

the capital city of Idaho, is located in the upper end of Boise Valley, 

8 miles- below the mouth of Boise River Canyon and 22 miles down* 

stream from Arrow Rock Dam. The other principal cities are
4 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

Caldwell and Nampa. The Union Pacific Railroad passes through 

the Valley, crossing the river at Caldwell.

Agriculture is the most important industry, consisting mainly of 

dairying and general farming. In some parts of the valley, fruit 

and special crops such as potatoes, peas, and head lettuce are grown. 

Dry farming and stock raising are carried on in parts of the Moore 

Creek and South Fork Basins. Sheep and cattle are grazed in the 

national forests late in spring and during the summer months.

Gold was first discovered near Idaho City, once the Capital of 

Idaho, in 1862.. Since that time placer and hard-rock mining have 

been carried on in the Moore Creek Basin. Other mining properties 

have been or are now being operated near Atlanta on the Middle 

Fork and Rocky Bar on the South Fork.

The mountainous areas of Boise River watershed are in general 

covered with species of pine, fir, and spruce, depending on elevation, 

exposure, precipitation, and the condition of the soil. Logging 

operations have been carried on extensively since the discovery of gold. 

In 1904 the Barber Lumber Co. constructed a mill and dam at Barber, 

7 miles southeast of Boise, and in 1914 the Boise Payette Lumber Co. 

acquired the property. Logs were shipped from the Idaho City area 

by rail. Timber cut in the North, Middle, and South Forks Basins 

was floated down the rivers during the spring runoff each year. 

Arrow Rock Dam, which was completed in 1917, is provided with a 

log chute. By 1935 all the readily accessible timber had been logged 

off and the mill was dismantled. The Boise and Sawtooth National 

Forests include 2,160 square miles of forested and grazing areas drained 

by the Boise River and its tributaries. The boundary line of the 

Boise National Forest crosses Boise River about 2 miles below Arrow 

Rock Dam. The main drainage features and the location of 13 

stream-flow and sediment-measuring stations are shown on the map 

in plate I.

TOPOGRAPHY AND DRAINAGE

The topography of the Boise River drainage basin varies from 

rugged and mountainous in the upper or eastern part of the basin to 

essentially flat in the lower or western part. Elevations range from a 

maximum of about 10,000 feet in the Boise River headwaters near 

Atlanta to about 2,200 feet at Parma near its mouth. The mountainous areas at the higher elevations are in general covered with timber except in regions where extensive logging operations or serious 

burns have occurred. Areas at lower elevations support only desert 

vegetation except along stream channels and on irrigated land. The 

mountains are composed chiefly of granites and comprise about twothirds of the drainage area. Weathered granites are the source of
BOISE KIVER DRAINAGE BASIN 5

most of the sediments in the streams. Extensive lava flows have left 

beds of basalt several hundred feet thick in parts of the valley of the 

South Fork of the Boise Eiver. Eemnants of these flows also are 

found in the lower part of Moore Creek Basin and in other parts of 

the Boise River drainage basin.

Boise River, one of the larger tributaries of the Snake River, has a 

drainage area of 3,820 square miles above the gaging station,at Notus. 

It is formed by the confluence of the North and Middle Forks near 

Twin Springs. The South Fork, the largest of the major tributaries, 

discharges into the Boise River just above Arrow Rock Dam. The 

North and Middle Forks have the most productive watersheds, as 

their headwaters lie on the western slope of the Sawtooth Mountains. 

This short range of mountains has some of the nighest peaks in southern Idaho and are the source of several other rivers that drain into 

the Snake River.

The maximum discharge of record (regulated) for the Boise River 

at the Bowling Ranch gaging station Smiles below Arrow Rock Dam 

was 17,600 second-feet in 1928. Moore Creek, the only remaining 

tributary of any magnitude, discharges into the river about a mile 

below the Bowling ranch station. The combined drainage area at 

the mouth of Moore Creek is about 2,650 square miles. The tributary 

inflow below this point is rather inconsequential except for occasional 

flood runoff from desert areas from melting snow.

Deer Flat Reservoir, near Nampa, is filled, each spring when the 

runoff is sufficient, by Moore Creek flow and releases from Arrow 

Rock Reservoir. TJiis water is diverted from the Boise River at 

Diversion Dam, 8 miles downstream from Moore Creek and is 

delivered to the reservoir through the New York Canal.

Floods, or the maximum discharge for the Boise River, usually 

occur during the latter part of May or the first part of June and 

result from melting snow in the higher mountain areas. The peak 

discharge for Moore Creek generally occurs in February or March, 

as a greater part of its drainage area is at a much lower elevation.

CLIMATE

Winters in the mountainous areas are long and severe. Snowfall 

^is heavy and temperatures below zero are common. Many highways 

over the high passes are, blocked with snow for several months each 

year. Summers are characterized by warm days and cool nights. 

At the higher altitudes frosts may be expected during every month 

of the year. -

In the* areas at lower altitudes, which include Boise and practically 

all the irrigated lands, winters are usually mild, although temperatures 

below zero are experienced at times during some years. Snowfall is
6 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

ordinarily light, seldom remaining on the ground for more than a few 

days at a time, Summers &re usually hot, but the humidity is seldom 

high enough to be oppressive. Temperatures of 100° F. and above 

are not unusual.

Precipitation is heaviest in the mountains and lightest in the plains. 

Most of the annual precipitation occurs during fall, winter, and spring; 

summers are usually dry over the entire area. At the higher altitudes 

a large proportion of the precipitation occurs as snow, a greater part 

of which reaches the streams as surface runoff, and is largely responsible for the peak discharges experienced in May and June. Part also 

percolates into the ground to the water table and reaches the streams 

as ground water runoff which contributes most of the water to the 

perennial streams during the late summer monthsMonthly and annual precipitation and temperature records for 

three United States Weather Bureau stations within the Boise River 

drainage basin are given for the 3-year period ended September 30, 

1940, and are shown graphically in figures 1 to 6.

OCT. NOV. DEC. JAN. FEB. MAR? APR. JUNE JULY AUS. S PT.

FIGURE 1. Cumulative precipitation at Idaho City for 3-year period ended September 30, 1040, and the

normal for 35 years.
BOISE BIVBR miAINAQE BASIN

OCT. NOV. DEC. JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT.

FIGUKS 2. Cumulative precipitation at Arrow Rock for 3-year period ended September 30,1940, and the

normal for*28 years. . ,

OCT. NOV. DEC. JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT.

FIQUKE 3. Cumulative precipitation at Boise for 3-year period ended .September 30,1940, and the normal

for 77 years.
8 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

OCT. NOV. DEC. JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT.

FIGURE^. Mean monthly temperatures at Idaho City for 3-year period ended September 30,1940, and the

normal for 35 years.

OCT. NOV. DEC. JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT.

PIGUEE 5. Mean monthly temperatures at Arrow Eork for 3-year period ended September 30,1940, and the

normal for 28 years.
BOISE RIVER DRAINAGE BASIN 9

OCT. NOV. DEC. JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. 

FIGITEE 6. Mean monthly temperatures at Boise for 3-year period ended September 30, 1940. and the

normal for 77 years.

The stations for which records of precipitation and temperature are 

available are at Idaho City, Arrow Rock, and Boise, at altitudes of 

4,000, 3,230, and 2,705 feet, respectively. Precipitation and temperature records for those stations have been obtained and published by

Precipitation in inches for 3-year period ended Sept. 80, 1940, at Idaho City,

Arrow Rock, and Boise l

November... . 

December. . . .

January...... 

February __

April.........

July... .......

September.. . 

Total.......

Idaho City (elevation 4,000 

feet)

1937- 

38

1.32 

3.16 

5.80

3.47 

2.11 

6.15

.47 

2.98 

2.07

1.06 

.05 

.25

28.89

1938- 

39

2.19 

3.21 

2.78

2.74 

3.65 

1.37

.71 

.36 

.50

.26 

.02 

1.50

19.19

1939- 

40

0.90 

0 

2.75

3.30 

6.80 

3.90

1.70 

0 

.12

.66 

0 

2.18

22.31

Normal 35 

years

1.58 

3.10 

3.02

3.17 

2.82 

2.32

1.30 

1.40 

1.08

.44 

.41 

.70

21.34

Arrow Rock (elevation 3,230 

feet)

1937- 

38

1.36 

3.17 

3.65

3.08 

1.03 

4.36

.73 

2.71 

2.35

2.09 

0 

.14

24. S7

1938- 

39

1.57 

3.40 

1.60

1.85 

2.89 

.80

.60 

.15 

.21

.26 

.11 

1.38

14.82

1939- 

40

2.00 

.03 

1.97

3.17 

4.13 

2.89

3.04. 

.08 

.08

.31 

.05

a 43

20.18

Normal 28 

years

1.31

2.77 

2.38

2.90 

2.37 

2.09

1.43

1.24 

.96

.32 

.26 

.50

18.53

Boise (elevation 2,705 feet)

1937- 

38

1.18 

1.71 

2.10

1.51

.82 

3.16

1.09 

2.55 

1.29

.85 

.03 

.34

16.63

1938- 

39

1.68 

2.51 

.57

1.19 

1.88 

.76

.36 

.11 

.38

.15 

Tr. 

1.53

10.62

1939- 

40

0.70 

.13 

1.39

21.84 

1.78 

2.26

1.80 

.09 

.08

.36 

.01 

1.87

12.31

Normal 77 

years

1.24 

1.28 

1.57

1.73 

1.44 

1.36

1.19 

1.41 

.91

.24 

.19

.55

13.11

i From TJ: S. Weather Bureau records. 

8 Station moved.
DISCHARGE AND SEDIMENT, BOISE EIVER BASIN

the United States Weather Bureau, as follows: Idaho City, 35 years; 

Arrow Rock, 28 years; and Boise, 77 years. The station at Boise was 

moved from the Federal Building to the airport in January 1940.

Temperature in ° F. for S~year period ended Sept. SO, 1940, at Idaho City, Arrow

^ and Boise l

November __ 

December....

February.-.--

ApriL. .......

July..........

September _ 

Average 

Idaho City (elevation 4,000 

feet)

1937- 

38

49.1

37.8 

28.4

27.0 

31.6 

34.0-

45.2 

60.1 

69.6

66.4 

64.9 

63.0

46.4

1938- 

39

49.6 

29.2 

28.6

26.7 

-23.2 

36.6

47.7 

56.2 

56.6

68.8 68.5' 

68.4

46.8

1939- 

40

47.8 

38.1 

34.6

30.1 

32.7 

40.4

46.2 

56.4 

64.0

68.4 

68.1 

69.3

48.8

Normal 35 

years

. 48.0 

35.7 

26.6

24.1 

28.9 

 35.1

44.0 

52.9 

69.6

67.3 

65.8 

57.0

45.3

Arrow Eock (elevation 3,230 

feet)

1937- 

38

51.0 

40.6 

31.7

28.1 

35.8 

37.3

49.0 

54.2 

65.1

72.6 

70.6 

67.1

50.3

1938- 

39

51.0 

31.4

29.7

27.0 

22.6 

36.1

60.4 

60.1 

61.2

74.2 

74.8 

62.2

48.4

1939- 

40

48.8 

38.8 

35.4

31.0

34.4 

42.8

48.4 

60.8 

69.2

75.2 

75.1 

62.6

51.9

Normals 

years

60.7 

37.5 

27.0

24.5 

30.4 

39.1

48.7 

57.2 

65.2

74.6 

72.7 

62.3

49.2

Boise (elevation 2,705 feet)

1937- 

38

55.2 

45.7 

37.5

36.9 

40.6 

41.8

51.8 

56.2 

67.0

75.0

71.8 

68.6

53.9

1938- 

39

54.0 

35.6 

34.2

34.0 

30.4 

44.4

53.6 

61.8 

63.1

75.9 

74.7 

64.3

52.2

1939- 

40

52.3 

42.4 

40.2

233.0

38.9 

45.6

60.0 

61.3 

69.6

74:9 

74.2 

63.2

53.8

Normal 77 

years

51.1 

41.0 

32.1

29.8 

34.9 

42.7

60.4 

57.2 

65.4

72.9 

71.8 

61.9

60.9

i From U. S. Weather Bureau records. 

* Station moved.

The records show wide variations in precipitation with respect to 

location and altitude. Precipitation at all three stations was above 

normal in 1938, below normal in 1939, and approached the long-time 

average in 1940. Maximum and minimum annual precipitation at 

tjie three stations for the period 1914-40, together with the calendar 

years in which they occurred; are given in the following table.

Maximum and minimum annual precipitation, 1914~40

Station

Idaho City __-. _. _ . __ .... _ .__._._ .

Arrow Eock _______________________

Boise.. ____ . ___ . ______________ . ...

Maximum

Amount 

(inches)

33.48 

25.44 

15.41

Calendar 

year

1927 

1927 

1927

Minimum

Amount 

(inches)

14.53 

10.61 

7.95

Calendar 

year

1924 

1924 

1933

The temperature records indicate that the year ended September 30, 

1940, was generally warmer than the years 1938 and 1939. At Idaho 

City the average temperature during 1940 was 3.5° F. above the 35- 

year average. During 1939 the averages at all three stations 

approached the long-time averages although there was considerable 

variation from the normal during individual months.
UNITED STATES DEPARTMENT OF THE INTERIOR 

GEOLOGICAL SURVEY WATER SUPPLY PAPER 1048 PLATE 1

N

1.

2.

3.

4.

5.

6.

7.

8.

9.

10. 

lOa.

11. 

lla.

12. 

13.

PLEASANT VALLEY~\ 

RESERVOIR_f

LIST OF STATIONS

Boise River near Twin Springs

Boise River at Dowling Ranch near Arrow Rock

Boise River at Notus

Cottonwood Creek at Arrow Rock Reservoir

Grouse Creek near Arrow Rock

Moore Creek above Granite Creek near Idaho City

Moore Creek above Thorn Creek near Idaho City

Granite Creek near Idaho City

Bannock Creek near Idaho City

Pine Creek near Idaho City

Pine Creek above Barry Placar Diversion near Idaho City

Elk Creek near Idaho City

Elk Creek above Gold Hill Placer Diversion near Idaho City

New York Canal near Barber

Cottonwood Gulch at Boise

EXPLANATION

O7

U. S. Geological Survey stream gaging 

and sediment station

Boundary Boise River drainage basin

Boundary area outside drainage basin 

irrigated by Boise River water

MAP OF THE BOISE RIVER DRAINAGE BASIN 758529 O - 48 (Face p. 10)
BOESE BIVER DRAINAGE BASIN 11

STREAM GRADIENTS ,

I (

Stream gradients in different parts of the Boise. River drainage area 

vary within wide limits. Gradients in the mountainous area are 

generally steep, ranging from about 20 to 200 feet per mile; those in 

the Boise River Valley are more gentle, averaging from 9 to 13 feet 

per mile. The gradients of streams obviously are related to their 

capacity for transporting sediments. As the gradients decrease, the 

transporting power of the stream diminishes. Other factors influencing the rate of sediment transportation are the size of particles of 

the material transported, the availability of sediment for transportation, and the roughness of the stream bed. The velocity of the 

stream, also an important factor, is a function of the gradient, the 

roughness of the stream bed, and the hydraulic radius.

' / Stream gradients in the Boise River drainage basin

Stream

North Fork, Boise River.

Middle Fork, Boise 

River. 

South Fork, Boise River.. 

Do..... 

Do.......... ......

Do. . 

DoDo. . .

Reach

From 5,400-foot contour to confluence of 

Middle Fork of Boise River. 

From 5,400-foot contour to confluence of 

North Fork of Boise River. 

From 6,400-foot contour to 5,400-foot contour..

Boise Riyer to Arrow Rock Dam. 

Arrow Rock Dam to Boise (8th J3t. Bridge) ...

River.

Boise River.

Length 

of reach 

(miles)

33.4 

39.1

13.4 

92.6

23.8

22

50

8

9

17

4

Fall in 

reach 

(feet)

1,926 

1,926 

1,000

9 A.A4.

518

282

464

1 400

450

670

800

Gradient 

(feet per 

mile)

58 

49

75 

26

22

13

9

175

50

39

200'

1 Gaging station on Moore Creek above Granite Creek.

2 Gaging station on Moore Creek above Thorn Greek.

8 Maximum water-surface elevation in Arrow Rock Reservoir in 1939 was 3,219 feet.

RESERVOIRS

There are three reservoirs in the Boise River drainage basin for 

which storage 'or gage-height records are available. These records are 

given in the annual series of water-supply papers on surface water 

that are published by the Geological Survey.

Arrow Rock Reser-voir is formed by Arrow Rock Dam (see pi. 2), 

which is located on the Boise River at Arrow Rock, Idaho, 22 miles 

by road east of Boise, and 4 miles above Moore Creek. The capacity 

of the reservoir is 291,600 acre-feet between elevations of 2,956 feet 

(11 feet below center line of sluice gates, 8.5 feet below sill) and 3,216 

feet (crest of movable spillway at highest position). Dead storage is 

negligible. Boise project officials state that the total capacity of the 

reservoir'may have been reduced by as much as 5,000 to 6,000 acre758529 48 2
12 DISCHARGE AND SEDIMENT, BOISE K1YER BASlN

feet by the deposition of sediment since the reservoir was completed 

in 1915. Water from the reservoir is used for irrigation of lands in 

Boise Valley.

Deer Flat Reservoir is an off-stream reservoir about 20 miles 

west of Boise and about 4 miles southwest of Nampa. The capacity 

of the reservoir is 177,150 acre-feet between gage heights 0.0 feet 

(sill of outlet gages) and 30.0 feet (maximum operating level). Dead 

storage is about 13,000 acre-feet. In addition to water from local 

drainage, the reservoir receives water from the Boise River through 

the New York Canal. Water is used for irrigation of lower Boise 

River project lands.

Little Camas Reservoir is located on Little Camas Creek 4 miles 

northeast of Bennett and 22 miles northeast of Mountain Home. The 

capacity of the reservoir is 22,300 acre-feet between gage heights 

4,931.0 feet (4.5 feet above bottom of outlet) and 4,965.0 feet (crest 

of spillway). Dead storage is unknown. Water is diverted from the 

Boise River basin for irrigation of about 5,000 acres of land in the 

vicinity of Mountain Home.

Three smaller reservoirs in the drainage basin for which gage-height 

or storage records are not available are Orchard, capacity 4,800 acre-r 

feet; Pleasant Valley, capacity 7,900 acre-feet; and Hubbard, capacity 

7,500 acre-feet.

IRRIGATED AREAS

About 333,000 acres in the Boise River Valley are irrigated by 

water from the Boise River and its tributaries. Practically all the 

area is located in the Boise River Valley between Diversion Dam, 

about 8 miles southeast of Boise, and the mouth of the river at the 

Idaho-Oregon State line about 45 miles northwest of Boise. A small 

area outside of the Boise River drainage-basin, lying in southwestern 

Canyon County, Idaho, and in eastern Malheur County, Oregon, 

also is irrigated by water from the Boise River. Another small area 

comprising about 5,000 acres in the vicinity of Mountain Home is 

irrigated by releases from Little Camas Reservoir,' which impounds 

water from small tributaries of the South Fork of the Boise River.

PLACER-MINING AREAS ' ,

The recovery of gold from placer deposits has been carried on in the 

Boise Basin since its discovery in 1862. x The name, Boise Basin, 

formerly Idaho Basin, has been given to the mining area drained by

i Metzger, O. H. Reconnaissance of placer mining in Boise County, Idaho: Bur. Mines Information 

Circ. 7028, August 1938.
BOISE RIVER DRAINAGE BASIN - 13

Moore Creek and its tributaries. Mining there has been done by 

dredging and by hydraulic and 'hand methods. Dredging of the 

stream-gravels began in 1896 at a point 4% miles above the mouth of 

Grimes Creek.2 During the period of the investigation covered by 

this report dredges were operated on Grimes Creek and on Moore 

Creek below Idaho City. No stream-flow or sediment-measuring 

stations were located on Grimes Creek. Hydraulic and hand methods 

also were used on placers on Moore Creek, the most active of which 

were located above Idaho City. Placers operated in other parts of 

the Boise River drainage basin were small and had relatively little 

effect on the streams. .

The most important factor, other than those due to nature, affecting sediment loads during the period of investigation was the operation 

of a large bucket-line dredge in the narrow valley adjacent to Idaho 

City. The dredged area extends from a point about one-fourth mile 

above the station on Moore Creek above Thorn Creek to a point 

near the mouth of Granite Creek, a distance of about 9 miles. Tailings from-the dredge have been dumped in large piles over the valley. 

Dredging operations occasionally interfere with the course of Moore 

Creek and the channel in the area adjacent to Idaho City has been 

shifted from time to time. The water level in the "dredge pool" is 

maintained by building dikes and by controlling the inflow. Other 

dikes or ridges and deep pools result from the normal operations of 

the dredge. Some of these pools created by earlier dredging near the 

mouth of Pine Creek are practically full of sediment. So long as the 

dikes below Idaho City remain intact and the pools are not filled they 

are effective in reducing the amount of coarse sediment removed from 

the area.

The Gold Hill Placer, near Idaho City, was the largest hydraulic 

placer in operation in the Boise Basin. Water for this placer was 

diverted from both Moore and Elk Creeks. Actual operation of the 

placer mine was limited to a few weeks late in the spring of 1939 and 

1940.

Rubow Placer, a small but active placer, was operated a short 

distance above the. gaging station on Elk Creek near Idaho City and 

on Spanish Fork which enters Elk Creek immediately below the 

station. Tailings from this placer filled the -stream channel with 

sediments to a depth of about 2.5 feet in the vicinity of the station. 

The station was moved to a new site on February 4, 1940.

2 Lindgren, Waldemar, The mining districts of the Idaho Basin and the Boise Ridge, Idaho, TJ. 8. Geol. 

Survey. 18th Ann. Kept., pp. 617-744,1898.
14 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

AREAS SELECTED FOB RUNOFF AND SEDIMENT-LOAD MEASUREMENTS

The following brief descriptions of the drainage areas selected for 

special runoff and sediment-load investigation were prepared by 

J. P. Thompson 3 of the Soil Conservation Service:

* * * ,a general analysis of the situation on the watershed as a -whole 

suggests that the most important watershed conditions 'to be sampled are as 

follows: '

1. Placered areas

2. Burnei areas

3. Cut-over areas

4. Virgin timber are*as

5. Range areas in three different stages of depletion.

.To determine the effect of placer mining, samples are taken on lower Moore 

Creek below an active placer area. The silt measurements at this station are 

compared with measurements taken on all of the major tributaries which come 

into Moore Creek above the placer area. These include the. Elk Creek station 

characterized by old placer operations, extensive burn and logged conditions, and 

intensive grazing. The upper Moore Creek station is below an area characterized 

in part by virgin timber, but grazed, a portion of a bad burn, and old placer diggings. The remaining three stations are on small tributaries of between 4,000 and 

5,000 acres each, Granite Creek being characterized by an old burn, Bannock Creek 

by virgin Ponderosa pine and Pine Creek by a recent logging operation of 

Ponderosa pine.

Twin Springs station samples the entire upper and middle fork of Boise River 

watershed, which is characterized by mixed forest, grass, and brush vegetation in 

relatively good condition. * * * The Notus station measures the silt leaving 

the basin. There are three smaller watersheds, namely Cottonwood Creek, 

Grouse Creek, and Cottonwood Gulch, which are representative of fairly good 

range, very seriously depleted range, and moderately depleted range conditions, 

respectively.

RUNOFF

MEASUREMENT OF RUNOFF

Runoff was measured at 13 gaging stations as an integral part of 

the sediment investigation. Three of the stations have been operated 

many years by the Geological Survey in cooperation with, the State 

of Idaho. One station, .on the New York Canal near Barber, was 

established originally by the Bureau of Reclamation, United States 

Department of the Interior, and has been operated during recent 

years by the Boise River watermaster. The New York Canal also is 

known as the Main South Side Canal. The remaining 9 stations were 

established especially for this investigation. The new stations were 

provided with equipment to meet the requirements of a program of 

3 to 5 years. The type of artificial control structure used was selected

3 Thompson, J. P., Report on the program of stream gaging and silt measurements, Boise River Watershed, Idaho, conducted by the United Ststes Department of the Interior, (geological Survey, Water Resources Branch, 1939: Typewritten report in flies of Soil Conservation Service, U. S. Dept. Af r. 1939.
RUNOFF 15

after a study of the physical characteristics of each stream. Waterstage recorders were installed in substantial wooden houses and 

wells. The equipment was improved at the 4 stations previously 

operated in connection with continuing cooperative programs.

Field reconnaissances of the several drainage areas during the early 

stages of tne investigation showed that diversions for placer mining 

operations were being made above a Duinber of the gaging stations. 

Arrangements were made to obtain supplemental records of discharge 

on those diversions affecting the runoff measured from the designated 

drainage basins. Immediately after authorization was received from 

the Flood Control Coordinating Committee of the Department of 

Agriculture to continue the investigation from January to June 1940, 

construction was begun on tVo new gaging stations tor replace two 

which were seriously affected by diversions. On February 4, 1940 

(see pi. 3 B) the station on Elk Creek was moved 4% miles upstream 

in order that the records obtained might more nearly represent runoff 

and sediment-load characteristics of the drainage basin. The station 

on Pine Creek (see pi. 4) was moved three-fourths of a mile upstream 

on February 13, 1940, to eliminate the effects of proposed placer 

mining operations adjacent to the original location. The changes in 

location, equipment, and drainage areas are given in the station 

descriptions. ' , The basic records collected at the gaging stations consist of records 

of stage, measurements of discharge and general information used to 

supplement the gage heights and discharge measurements ID determin- 

, ing the daily flow. The records of stage at all 13 gaging stations Were 

obtained from water-stage recorders that give a continuous record of 

fluctuation. Measurements of discharge were made with current 

meters in accordance with the standard practices of the Geological 

Survey, except when flows were too small to be obtained in the 

Ordinary manner. Measurements of these small flows were made 

with the portable V-notch and Cippoletti weirs. Discharges for weir 

measurements were computed by means of Cone's formulas,4 thus,

V-notch weir__.___#=2.49 H2-48

Cippoletti weir #=3.247 BHlA*-~®'6®® "^ fl">+0.609 H2-5

in which Q is the discharge in second-feet, B is the width of the weir 

crest in feet, and H is the depth in feet of water over the crest of the 

weir as measured in the pool above.

Rating tables giving the discharges for all stages recorded were 

prepared for each station from the discharge measurements. The 

application of the rating tables to the daily gage heights determined

4 O'Brien, M. P., and Hickox, O. H., Applied fluid mechanics, p. 146, McGraw-Hffl Book Co., 1937.
16 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

from the recorder graphs gives the daily discharges from which the 

monthly mean discharges were computed. The computation of 

sediment loads requires that frequent instantaneous discharges be 

determined during periods when fluctuations of stage are consequential.

Other data pertaining to the water supply of the Boise River drainage basin, collected under the regular cooperative stream-gaging 

program prior to and during the period of this investigation, published 

by the Geological Survey in the annual series of reports, Surface water 

supply of the United States, part 13, Snake River Basin (prior to 

1935, designated as part XII, B). The locality, kind of information 

and period covered are indicated below:

Arrow Rock Reservoir at Arrow Rock (contents) October 1917 to June

1940.

Boise River at Boise (discharge) March 1940 to June 1940. 

Boise River at Strawberry Glen Bridge near Boise (discharge) March

1938 to June 1940. 

South Fork of Boise River near Lenox (discharge) March 1911 to June

1940. 

Little Camas Reservoir near Bennett (fragmentary gage heights) March

1924 to September 1939. 

Little Camas Canal near Bennett (discharge, irrigation seasons only) 

1917, 1924 to 1940.

Moore Creek near Arrow Rock (discharge) December 1915 to June 1940. 

Deer Flat Reservoir near Caldwell (contents) October 1917 to June 1940. 

Diversions from Boise River (summary of discharge) irrigation seasons

1919-40.

The profile of the Boise River between Barber Dam and the mouth 

was developed by observing water-surface elevations at nine gages in 

the reach during the freshet period of 1938. Fragmentary repetition 

of the profile record was made during the season of 1939. These 

water-surface elevations are referred to sea level, United States Army 

Engineer datum, Boise River Surveys. (See Water-Supply Papers 

863 and 883.)

COMPARISON OF RUNOFF

In order to compare the runoff measured during the period of the 

investigation with that of, earlier years, stations on the Boise River 

near Twin Springs and on Moore Creek, at mouth, near Arrow Rock 

were selected as being representative of the Boise River and Moore 

Creek drainage basins, respectively. Records for 29 years on the 

Boise River and 24 years on Moore Creek are given in both tabular 

and graphical form. (See figs. 7, 8.) Although the period of the 

investigation covered only 18 months the figures given are for the 

water years ended September 30, 1939 and 1940, in order that they 

may be compared with the previous years of record.
RUNOFF 17

12,000

10,000

8,000

6,000

4,000

2,000

FIGUEE 7. Maximum discharge of Boise River near Twin Springs and Moore Creek near Arrow Bock 

for years ended September 30, 1939 and 1940.

2,000

1,500

1,000

1930 1935

FIGURE 8. Mean discharge of Boise Riror near Twin Springs and Moore Creek near Arrow Rock for years 

ended September 30, 1939 and 1940.
18 DISCHARGE AND SEDIMENT, BOISE KIVEK BASIN

Comparison of discharge in 1989 and 1940 with average and median for period of

record '

Boise River near Twin Springs

[Drainage area 830 square milesl

Average for year ended Sept. 30..: ___________

Maximum observed for period of record. _ ___ _

19

Discharge 

(secondfeet)

1,447

816

1,105

1,040

4,290

10,300

6,521

7,140

39

Percent of

28-year 

.-average

72

74

19

Discharge 

(secondfeet)

1,949

1,010

1,101

1,060-

5,210

10,300

6,476

7,060

10

Percent of 

29-year 

average

97

92

Moore Creek near Arrow Bock

[Drainage area 426 square miles]

Average for period Feb. 1 to June 30. __________

Average for year ended Sept. 30 _______ ..........

19

Discharge 

(secondfeet)

427

221

287

234

1,500

4,550

2,070

2,110

39 

Percent of

23-year 

average

72 '77

19

Discharge 

(secondfeet)

542

257

286

246

3,370

4,550

2,122

2,170

40

Percent 

of 24-year 

average

91

90

' These comparisons show that the runoff during 1940 was greater 

at both stations than during 1939 but below the average annual 

runoff for the period of record. The maximum observed discharge 

on Moore Creek during 1940 was greater than the maximums for all 

years except 1932 and 1936. Qn the day of maximum discharge in 

Moore Creek in 1940 (3,370 second-feet, March 27) the maximum 

sediment load for a single day (12,200 tons) was measured at the 

gaging station on the New York Canal. Since there were no releases 

from Arrow Rock Reservoir between March 18 and April 1, 1940, 

the river flow at Diversion Dam during this period consisted only of 

stream flow from Moore Creek and minor tributaries. The sediment 

loads consisted of material brought in by Moore Creek and material 

scoured from the sediment deposits in the Boise River qhannel above* 

Diversion Dam.

Records of the spring runoff for the 13 stations operated during 

the period of investigation show that the flow was greater in 1940 

than in 1939. Runoff is reported in inches in the following table for 

only those stations above which there was no appreciable regulation 

or diversion.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1048 PLATE 2

ARROW ROCK DAM ON BOISE RIVER AT ARROW ROCK, IDAHO. 

Photograph by U. S. Bureau of Reclamation.
GEOLOGICAL SURVEY WATEE-STJPPLY PAPEE 1048 PLATE 3

A. COTTONWOOD CREEK AT ARROW ROCK RESERVOIR. 

3road-crested weir with trapezoidal notch for low stages. Discharge-about 8 second-feet.

'

B. ELK CREEK ABOVE GOLD HILL PLACER DIVERSION. 

Discharge about 50 second-feet. Overfall structure for sediment sampling in foreground.
SEDIMENT LOADS 19

Discharge measured during spring runoff of WS9 and 1940 February-June

Station

Grouse Creek- - - ... ---- .. -.-- _ -

193

Acre-feet

430,400

4,980

1,740

35, 330

628

470

1,990

797,900

244,100

IB 71A

612

8,030

447,000

9

Inches 1

9.73

4.36

. 4.09

5.68

2.46

1.97

2.34

194

Acre-feet

583,600

0,280

1,960

44,600

887

761

9,040

2,200

946,800

444,000

18,080

787

470, 600

0

Inches 1

13.18

5.52

4.61

7.03

3,47

3.17

12.95

2.57

i__

Runoff in inches not reported for last 7 stations ta the table because of appreciable regulation or diversion above stations.

a Station operated Feb. 4, to June 30,1940. 

3 Station operated Jan. 6,1939 to Feb. 12,1940. 

< Station operated Feb. 13 to June 30.1940. 

 Station operated Jan. 20,1939 to Feb. 4,1940.

DIVERSIONS FROM THE BOISE RIVER

Between the gaging stations at Dowling ranch and Notus, 27 

principal canals and several small farm laterals divert water from 

th-3 Boise River for irrigation. Records«for the year 1919 to 1940 are 

available. Records of? the daily diversions subsequent to 1915 are on 

file in the office of the Idaho Commissioner of Reclamation; Daily 

gage heights were obtained, frequent discharge measurements were 

made, and the records were summarized under the direction o£W. E. 

Welsh, water-master for Boise River. The total amount of water 

diverted by these canals during the irrigation season of 1939 was 

1,253,000 acre-feet. Of this total 567,640 acre-feet was diverted by 

the New York Canal, which* is the main canal of the Bureau of Reclamation, and 146,460 acre-febt by the Ridenbaugh Canal, the second 

largest.canal in the area.

SEDIMENT LOADS

» i

DEFINITION OF TERMS i '

In this paper certain terms, which depart from the usual terminology, are used in the discussion of sediment loads. Definitions of 

these terms have been adapted from: (1) Reports 1 and 3 of a series of 

9 issued in connection with a study of methods used in measurement 

and analysis of sediment loads in streams conducted jointly by the 

Geological Survey, Corps of Engineers, Department of Agriculture, 

Office of Indian Affairs, Tennessee Valley Authority, Bureau of 

Reclamation, and Iowa Institute of Hydraulic Research at the 

Hydraulic Laboratory, State University of Iowa, Iowa City, Iowa;
20 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

and (2) Geological Survey Professional Paper 86, "The transportation 

of debris by running water," by G. K. Gilbert.

Sediment is fragmental material transported by, suspended in, or 

deposited by, water or air, or accumulated in beds by other natural 

agents.

Suspended sediment is sediment that remains in suspension in water 

for a considerable period of time without contact with the bottom.

Deposited sediment is sediment that has been temporarily or permanently deposited from suspension .in water.

Sediment concentration is the ratio of the weight of the sediment in 

a water-sediment mixture to the total weight of the mixture. It is 

expressed in parts per million in the reports issued in connection with 

the Boise River sediment investigation.

The sediment load is the amount of sediment carried by a stream 

past a reference point, as a gaging station. In this report it refers 

either to the material carried in suspension or to the total amount of 

material transported including the so-called bed load.

A point sample is a sample of water and sediment obtained at a 

single point in the cross section of a stream with an instantaneous type 

of sampler. All point samples were taken with the Tait-Binckley 

sampler.

A bottom sample is a point sample collected at* the bottom of a 

stream, ordinarily including material from the bottom 2% inches.

An integrated (or depth^ntegrated) sample is a sample collected in 

such a manner that it contains water and sediment from all points in 

the vertical section of a stream.

Bed load is that part of the sediment load which is in almost continuous contact with the stream bed and is being rolled or pushed 

along by the force of the moving water.

A dune is a form of bed load in which sediment moves along the 

bottom of a stream, molded into a hill that travels downstream. 

Material is eroded from the upstream face and deposited on the downstream face by the flowing water.

COLLECTION OF SEDIMENT SAMPLES

During the 18-month period of investigation a total of 43,900 

sediment samples were collected at the 13 stream-flow, sedimentmeasuring stations. At the main river stations samples were collected 

from the cable-car installations. At the tributary stations the samples 

were taken from foot bridges near the natural or artificial controls.

SAMPLING EQUIPMENT

The' sampling equipment used by the Geological Survey prior to 

this investigation consisted of the Tait-Binckley, Colorado River,
SEDIMENT LOADS 21

and brass-pipe samplers. The Tait-Binckley sampler was used to 

collect instantaneous samples when depths and velocities were not 

excessive. The Colorado River sampler was used to collect both 

point-integrated and depth-integrated samples, but the brass-pipe 

sampler was limited to the collection of depth-integrated samples.

Because of the wide range of sampling conditions encountered on 

the Boise River and tributaries it was necessary to modify the available equipment and develop new in order to obtain reliable results.

Two types'of depth-integrating samplers were used. The first type 

consisted o'f a pint milk bottle supported on a rigid handle. (See pi. 

QB.) The bottle was fitted with a rubber cap having a hole about %- 

inch in diameter and a piece of small copper tubing for an air exhaust. 

The air exhaust permitted the water-sediment mixture to enter the 

b'ottle smoothly without bubbling action. The holder for the bottle 

was fastened to the handle in such a manner that the opening in the 

rubber cap was nearly parallel to the direction of flow. This sampler 

was used at those stations having overfall sections.

A variation of the first type of sampler consisted of a quart milk 

bottle held in a horizontal position in a frame fastened to a rigid handle, 

(See pi. 'QA.) A rubber cap with a %-inch hole and air exhaust were 

used as with the pint milk bottle. The hole, however, was off center 

which made it possible to collect a satisfactory sample without any 

loss of the water-sediment mixture. This sampler permitted the 

collection of depth-integrated samples to a point within 0.2 feet of the 

bottom. It was used at those stations without overfall sections and 

where the depths seldom exceeded 3 feet.

A second type of depth-integrating sampler was used at the large 

river stations where the use of rigid handle samplers was impracticable. 

It consisted of a pint milk bottle held in a vertical position in, a piece 

of brass pipe to which was fastened an auxiliary lead weight for use 

during high stages. The bottle was fitted with a rubber cap and air 

exhaust similar to that used in the other depth-integrating samplers. 

It was lowered to the stream bed and raised by means of a small rope. 

With this type of sampler it was not possible to collect sediment samples 

closer.than about 0.8 foot from the bottom.

Point samples were collected with the Tait-Binckley sampler/ (See 

pi. 5 A and B.) The sampler consists of three cylindrical metal tubes 

of equal diameter mounted coaxially on line in a horizontal frame. 

The middle tube, which is the sample container, is mounted in bearings 

so that it is free to rotate about its axis and is connected to the two 

rigidly mounted end cylinders by sections of thin rubber tubing. In 

operation the sampler is lowered to the desired depth in the open 

position. The middle section is then rotated by pulling on an auxiliary 

line wound around that section, thus twisting the rubber sections and
22 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

sealing jbhe water-sediment mixture in the-middle se'ction'. This 

sampler was used for the collection of special samples at all stations.

SAMPIJNG PROCEDURE

Sampling procedure used by the Geological Survey on earlier investigations was based on^ a technique developed on rivers of appreciable 

size and depth. Integrated samples were collected in pint milk boitles 

held in a vertical position. Instantaneous ppint samples were collected with the Tait-Binckley sampler. In this investigation sampling 

procedure and equipment were modified to fit the conditions encountered in a manner suited to give the best results without a laboratory 

investigation of the equipment available. All depth integrated samples 

were collected with the entrance hole open while lowering and raising 

the sampler vertically. At those stations having overfall sections the 

bottle was lowered and returned through the nappe from two to five 

times until it was nearly but not quite full. Successive lowerings were 

distributed across the weir rather than being made at a single point, 

thus integrating both the horizontal and vertical sections. In lowering the bottle through the nappe it was held nearly parallel to the axis 

of flow in order that the opening in the cap would be pointed directly 

into the current. In powering it through the nappe, water-sediment 

mixtures were collected from all points in the vertical. From two to 

three samples were collected during each sampling period. Some stations have broad-crested weirs with overfalls in,two or three sections. 

During high stages at these stations at least two samples were taken 

in each section, at each sampling period.

At stations without overfall sections depth-integrated samples were 

collected in much the same manner as at the overfall sections except 

that it was not possible to obtain water and sediment moving close to 

the bottom. The distance above the bottom in which the sampler was 

in operation was 0.2 or 0.8 foot depending on the type of sampling 

device used. Ordinarily three depth-integrated samples were collected during each sampling period in vertical sections approximately 

one-fourth, one-half, and three-fourths of the distance across the 

stream. * v

Point samples were collected with the Tait-Binckley sampler at 

frequent intervals at all stations without overfalls. Each set of 

samples ordinarily consisted of 9 or 12 samples; 3 surface, 3 mid-depth, 

and 3 bottom samples, and usually 3 samples at a point from 0.2 to 

1.0 foot above the bottom. A sample was taken by lowering the 

sampler to the desired depth in the open position and, 1 to 2 seconds 

later, closing it by pulling the auxiliary line.
BBKMfiNT LOADS 23

Since the number of samples in each set of point samples amounted 

to three to four times the number of depth integrated samples ordinarily collected at each sampling period, it was not practicable to 

use this apparatus for routine work at all the stations without overfalls. However, from February 10 through June 30, 1940, from two 

to three set's of point samples were collected daily from the New York 

Canal and at least once daily from the Boise River at Dowling ranch. 

Tabulated sediment loads for this period are based on point samples 

for those two stations. ,

SAMPLING FREQUENCY

The frequency of sampling was determined with reference to variations in sediment content resulting from changes of stage or from other 

causes. Major changes of stage during the spring runoff resulted 

from melting snow usually accompanied by rain. Minor changes of 

stage during the day resulted from diurnal fluctuations of temperature. Increases in stage were usually accpnipanied by increases in 

sediment concentration. At stations on the smaller streams increases 

of 0.01 to»0.02 foot were frequently accompanied by large increases in 

sediment content. At times there were increases in sediment when no 

increases in stage was recorded. Increases in sediment, and usually 

in stage, ordinarily occurred on the small streams between about noon 

and midnight. Decreases usually occurred during the other 12 hours.

During the period of spring runoff, samples were collected from 

3 to 12 times each day depending on the stream and its discharge and 

sediment characteristics. Because changes in stage and sediment 

concentration usually occur more suddenly in small streams than in 

large streams, samples were collected more frequently on the smaller 

streams.

The sediment content of depth-integrated samples collected at 

stations with overfalls frequently varied considerably even for samples 

collected consecutively. This is attributed to the fact that much of the 

material consisted of coarse sand and small pebbles and that there 

was a tendency for the coarse material to move across the weir intermittently. Streaks of coarse sand moving irregularly along the 

bottom were observed many times when the material in suspension 

was of such low concentration that sand moving on the bottom was 

clearly visible. Nevertheless, because two samples in the low-water 

section and two in the high-water section were taken at each sampling 

period during high water and because of the large number of sampling 

periods during the day, computed loads probably are a reliable measure of the total sediment loads passing the stations.
24 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN 

LABOEATOET? PEOCEDTTEE

DETERMINATION OF SEDIMENT CONCENTRATION OF SAMPLES

When the samples were received in the laboratory they were segregated by stations, weighed, and set aside to allow suspended matter 

to settle. If they did not settle clear within a few days, from 1 to 3 

milliliters of dilute hydrochloric acid (1 to 9) was added 24 hours before 

analysis to hasten coagulation. The clear water was siphoned off 

and discarded, and the remaining water and sediment were transferred 

with the aid of a stream of water from a wash bottle to a weighed 

glass evaporating dish or to a Gooch crucible, which previously had 

been provided with an asbestos mat, dried and weighed. Kesidues 

containing large quantities of sediment were usually transferred to 

evaporating dishes, and those containing only small amounts of sediment were filtered through Gooch crucibles. Kesidues in dishes were 

evaporated to dryness on a hot-air bath, dried in an oven for one hour 

at 110° C., cooled, and weighed. Kesidues in the crucibles were dried 

as completely as possible* by suction and then placed in the oven, 

dried for one hour at 110° C., cooled, and weighed. The, quotient 

obtained by dividing the weight of sediment in the sample in grams 

by the total weight of water and sediment in grams, multiplied by 

1,000,000, gives the concentration of sediment in the sample in parts 

per million. All sediment concentrations are expressed in parts per 

million.

DETERMINATION OF SIZE COMPOSITION OF SAMPI^ES

Samples on which size analyses were made were handled by a 

combination of the sieve and sedimentation methods commonly in 

use, as worked out in the laboratory of the Water Resources Branch 

of the Geological Survey. In the sieve method the maximum number 

of'sieves used in an analysis was seven. The actual, number used 

depended somewhat on the character of the material to be analyzed. 

The sieve openings, expressed in millimeters, were 4.00, 2.00, 1.00, 

0.50, 0.250, 0.149, and 0.074.

In the sedimentation method four separations were usually made. 

The maximum sizes of particles in each separation were, successively, 

0.074, 0.050, 0.020,>and 0.005 millimeter in diameter.

As soon as samples for analysis were received in the laboratory 

they were weighed and to each was added about 1 millimeter of 

formaldehyde to prevent the growth of algae. For the analysis the 

cldar water above the sediment was siphoned off and discarded. The 

sediment was washed on to the largest size sieve selected and washe.d 

free of all material that could pass through. The process was repeated 

with smaller-mesh sieves in order, including the 200 mesh-sieve (0.074 

millimeter openings). The material from each sieve was wasned into
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1048 PLATE 5

-...**. ....tmZ-"

A. OPEN POSITION. 

Adapted for use from footbridge.

B. CLOSED POSITION 

Adapted for use from cable car.

TAIT-BINCKLEY SAMPLER.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1048 PLATE 4

PINE CREEK ABOVE BARRY PLACER DIVERSION

Broad-crested weir with rectangular flume for low stages. Discharge 1.4 second-feet. Overfall structure for

sediment sampling in foreground.
SEDIMENT LOADS - '25

*»

a weighed evaporating dish, evaporated to dryness, dried at 110° C., 

cooled, and weighed.

The material passing the 200-mesh sieve was transferred to a tall 

glass cylinder and the volume adjusted to a definite height with tap 

water. Since Boise tap water contains only about 100 parts per 

million of dissolved solids, which is not much more than is found in 

water in samples from most of the stations, it was used in making 

the analyses. The material in the cylinder was allowed to settle for 

a predetermined time, according to Stokes' Law of settling velocities, 

for each size group^ after which the water containing unsettled material was decanted into other similar cylinders. The sediment 

remaining in each cylinder was transferred to weighed dishes, evaporated to dryness, dried at 110° C., cooled, and weighed. Since the time 

of settling varies with the temperature, tables were prepared showing 

the time of settling for each 2.5° of temperature on the centigrade 

scale and that table followed which was closest to room temperature 

at the time of analysis.

The total sediment content of each sample was taken to be the 

combined weights of the material measured in each size group. 

From this the percentage of sediment in each size group and the 

concentration in the original sample were computed.

Size analyses of suspended and deposited sediments are tabulated 

on pages 114 to 143. Results of the more important analyses are 

represented graphically.

COMPUTATION OF SEDIMENT LOADS

Sediment loads were computed in two ways depending on the rate 

of change of the concentration of sediment in" the samples and the 

rate of change in stage of the streams. During the periods of spring 

runoff the loads for most of the stations were computed in tons per 

hour from the content of dried sediment in parts per million and the 

corresponding discharge at the times when the samples were taken. 

The sediment loads in tons per hour were plotted in the form of continuous graphs for each day, and the daily loads in tons were determined by measuring with a planimeter the areas under the graphs. 

Data plotted for Moore Creek above Thorn Creek and for Granite 

Creek on? March 26 and 27, 1940, are reproduced in figures 9 and 10, 

respectively. Discharge and sediment concentration, which are 

shown for reference, are usually not plotted in practice.

During periods of low flow and periods when the sediment content 

was low and the discharge comparatively uniform, the daily loads 

were computed from sediment concentrations in daily samples, or in 

averages of two or more sets of samples per day, and the average discharge of the stream for that day.
26 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

M4RCH ?" I9-5O MARCH 27 I94O

FIGTTRE 9. Discharge, sediment concentrations, and sediment loads measured in Mbore Creek above Thorn

Creek, March 26-27,1940.

For the stations on the New York Canal and the Boise River at the 

Dowling ranch, average sediment concentrations in the cross section 

were determined during the spring runoff period of 1940 from the 

results of point samples. Samples were collected usually from four 

points in each, of three vertical sections distributed uniformly across 

the stream. Inasmuch as the New York Canal is concrete-lined and 

relatively smooth and flat at the bottom, average sediment concentration at this station was computed for each horizontal plane 

corresponding to the four levels at which samples were collected. 

These averages were plotted against depth and the average concentration in the vertical determined by graphical methods. Because 

the stream bottom at the Dowling ranch station is covered with rocks 

and is not uniform in depth, the average concentration in the cross 

section was determined first by computing the concentration in the 

vertical, as described above for each of the three sampling stations, 

and then by taking the average of the three vertical concentrations.
MARCH gS, 1940 MARCH 27, 1940

FIGHBE 10. Discharge, sediment concentrations, and sediment loads measured in Granite Creek near 

* " Idaho City, March 26-27,1940.

At stations where the overfalls consist of two .or more sections, 

discharge ratings were prepared and* corresponding sediment loads 

were computed for each section. Since sediment concentrations in 

samples from the low-water sections were usually considerably greater 

than those in the high-water sections, it was necessary to compute 

the loads carried in each section separately during periods of high water.

BASIS OF REPORTING SEDIMENT LOADS

The quantity of solid material passing a gaging station, as measured 

at a given time, is.referred to as the sediment load of the stream at 

that point. The term "sediment" has been adopted because it 

probably tetter describes^ particles of fragmental material than the 

term "silt," which is understood by some to represent material 

a particular range of particle size. .

758529 ii8 3
28 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

The term "sediment load" is used to represent the quantity of sediment measured, but it may not represent the total quantity of sediment passing the gaging station at that time. For those stations 

with .overfall sections the sediment loads were computed from integrated samples and are assumed to represent the total loads passing 

the stations. For those stations without overfall sections the sediment loads, with two exceptions, also were computed from integrated 

samples. However, since integrated samples from stations without 

overfall sections did not contain sediment from points at and near the 

bottom, the computed loads are assumed to represent only the sediment loads in suspension carried past those stations.

The stations on the Boise Kiver at Dowling Kanch and the New 

York Canal are the two for which daily sediment loads in 1940 were 

not computed from integrated samples. Loads for these stations 

were computed from point samples. The loads reported for the 

Dowling ranch station probably represent essentially the total 

quantities of sediment carried past the station. Data obtained in 

connection with bed-load observations on the New York Canal, 

however, show that the reported daily loads do not represent the entire 

amount of sediment carried past this station.

The stations for whick the reported loads represent the total sediment loads and those for which they represent the suspended-sediment 

loads are listed in two groups as follows:

Station

Boise River at Dowling ranch __ ___ .

Cottonwood Greek at Arrow Rock Reservoir.

Moore Creek above Granite Creek _ ... 

Moore Creek above Thorn Creek ........

Elk Creek.. .__.______.__..__.___________

Period for which suspendedsediment loads are reported

Jan. 17, 1939, to June 30, 1940 .

Jan. 17, 1939, to Feb. 9, 1940- .,

Jan. 13, 1939, to June 30, 1940, ...

Jan. 20, 1939, to June 30, 1940..._ 

Jan. 28, 1939, to June 30, 1940--..

Jan. 20, 1939, to Feb. 4, 1940. .._. 

Feb. 1, 1939, to Feb. 9, 1940. ....

> 

Period for which total sediment loads are reported

Feb. 10, 1940, to June 30, 1940.

Jan. 23, 1939, to June 30, 194£.

Jan. 20, 1939, to June 30, 1940.

Jan. 10, 1939, to June 30, 1940.

Jan. 16, 1939, to June 30, 1940.

Do.

Feb. 4, 1940, to June 30, 1940. 

Feb. 10, 1940, to June 30, 1940.

Jan. 27, 1939, to June 30, 1940.

RELIABILITY OF REPORTED SEDIMENT LOADS

The sediment-sampling equipment available for use in this investigation was not considered entirely adequate for all the sampling 

conditions encountered, but it was modified to give a satisfactory 

degree of accuracy.

Kesults of laboratory tests 5 made at the Jowa Institute of Hydraulic Research subsequent to the Boise River investigation show

»Report No. 5, Laboratory investigations of suspended sedimen* samples: U. S. Engineer District SubOffice, Hydraulic Laboratory, University of Iowa, Iowa City,, Iowa, 1941. " t
SEDIMENT LOADS - - * . - . 29

that the errors in sediment concentrations determined in samples collected with sampling devices with entrance conditions similar, to those 

in the horizontal depth-integrating sampler vary primarily with the 

size of particles in suspension and with the stream velocity. The 

errors, which are positive, increase both with increases in the size of 

the sediment particles a'nd with decreases in the ratio of the intake 

velocity to the. stream velocity. Sediment concentrations determined in samples collected with the vertical type of' depth-integrating sampler also are subject to errors resulting mainly from 

entrance conditions.

At the stations with overfall sections the reported loads were com" 

puted from depth-integrated samples that contained water-sedimentmixtures from all points in the vertical. Inasmuch as much of the, 

sediment carried past those stations-eonsisted of a large proportion 

of coarse material, there is reason to believe that some of the samples 

may have included more sediment ,than was representative of the 

water-sediment mixtures. On the other hand, it is known that at 

some of the stations considerable quantities of coarse gravel were 

transported by the streams that were not effectively sampled. Since 

no standard of reference was available for estimating the accuracy 

of samples collected at stations with overfall sections, it is tacitly 

assumed that the reported loads are representative of the actual total 

loads passing those stations.

At the stations without overfall sections the loads were computed 

on the basis that the average concentrations for the total depth were 

the same as those for the sampling depths. The water-sediment 

mixtures from points less than 0.8 foot from the bottom for the 

vertical type of integrating sampler and from points less than 0.2 

foot from the bottom for the horizontal type of integrating sampler 

were not included in the samples. Thus the sediment concentrations 

determined in samples collected with the vertical depth-integrating 

sampler were, usually appreciably smaller than actually existed in the 

streams at the times the samples were collected, owing to limited 

sampling depths and entrance conditions. Similarly, concentrations 

in samples collected with the horizontal depth-integrating sampler 

were affected by the limited sampling depth and entrance conditions.

Sediment concentrations computed from point samples are believed 

to represent more nearly the true concentrations in the stream than do 

the concentrations determined in the depth-integrated samples, not 

only because the point samples were taken at and near the bottom as 

well as at several other points in the vertical, but also because there 

was little disturbance of the stream-flow pattern of the water-sediment 

mixture approaching and entering the sampler.
S(l DISCHARGE AND SaMMBNT, BOBSE BIVE8 BASIN

* iBuring the spring runoff of 1940 the sediment loads reported iotf 

the Boise River at Bowling ranch and for the New York Carnal are 

ba^ed entirely on point samples^ which were collected from one to three 

times daily. For Bowling ranch the reported loads for 1940 are 

believed to represent essentially the actual total loads passing the 

station. For the New York Canal the reported loads are somewhat 

less than the actual loads largely because of the movement of large 

quantities of coarse sediment in dunes along the bottom of the Canal 

which could not be effectively sampled.

The vertical depth-integrating sampler was used at the stations on 

the Boise River at Bowling ranch and the New York Canal during 

1939 and at the stations -on the Boise River near Twin Springs afcd 

at Notus during 1939 and 1940. The h&rizontal depth-integrating 

sampler was used at 'the stations on Moore Creek, above GraniteCreek and above Thorn Creek, throughout the period of the investigation, and at the station on Elk. Creek near Idaho City during 1939.

In order to determine the approximate relation between sediment 

loads computed from point samples and loads computed from depthintegrating samples, point samples were collected at irregular intervals 

at those stations without overfall sections. From these results rough 

estimates were made, which indicate the proportion of the total loads 

that are represented by the loads computed from routine depthintegrated samples. Inasmuch as point samples were collected only 

two or three times a week at most of the stations, the estimates may 

be considerably in error. They do, however, give a rough indication 

of the total loads passing the stations.

Relation of reported suspended loads to total loads as indicated by point samples

Station

Boise River near Twin Springs.- _____ . _______________

Boise River at Notus- ________________________ <.* ____

Moore Greek above Granite Creek _____________ - _ - ,

.Elk Greek near Idaho City... _ I _ ....... ___ ..... _ . _____ . ......

New York OanaL. . _ . __ ....... __ . _____ .... .. 

Percent of total load

1839

60^80 

50 

80- 90 

96-105 

95-100 

fl5-105 

80-90

1940

50- 70 

95-100 

i 60-80 

S5-U)6 

65-100

85-80

SEDIMENT LOADS MEASURED IN STREAMS NEAR IDAHO CITY

At the beginning of the investigation the five stations, above Idaho 

City were above all active placer mines. They were on Moore Creek 

above Granite Creek and on Granite, Bannock, Pine, and Elk Creeks* 

The station on Moore Creek above Thorn Creek was situated belpw. 

all active placer mines on Moore Creek above the mouth of Grimea 

Creek. The stations on Pine and Elk Creeks wer& subsequently
movedupstream bemuse of actual or proposed placering oft those 

streams after the investigation was under way". - A s^mimary of the monthly sediment loads measured at the six 

stations in the Idaho City area is given in the accompanying table. 

The data, indicate that the loads measured at Moore Creek above 

Thorn Creek were a little smaller during the spring; runoff months of 

1939 and a little larger during the spring runoff months of 1940 than 

the sums of the loads measured at the five stations above Idaho City 

during the same periods. During periods of moderate and loir flow, 

however, the; loads measured at Moore Creek above Thorn Creek were 

considerably larger than the combined loads measured at the five 

.stations above Idaho City- This increase^ in sediment load probably 

is due almost entirely to placer-mining operations in the vicinity of 

Idaho City, inasmuch as the unmeasured inflow is negligible and can 

be disregarded as a source of sediment.

Size analyses of a large number of samples collected at stations in 

the Idaho City area give information about the origin and disposition 

of sediments carried past some of the gaging stations. Graphs of 

these analyses in figure 11 .show that during the spring runoff of 

1939 from about 60 to 90 percent of the material hi samples collected 

from Pine/Creek, Moore Creek above Granite Creek, and Elk and 

Granite Creeks consisted of particles greater than 0.100 millimeter 

in diameter, and that more than 70 percent of the material in samples 

from Pine and Bannock Creeks consisted of particles greater than 1.00 

millimeter in diameter. As classified by the former Bureau of Soils * 

now merged into the Bureau of Plant Industry, Soils, and Agricultural Engmeering-^material coarser than LOO millimeter is fine 

gravel. Although the analyses show that the material collected from 

Bannock Greek was very coarse, it should be pointed out that 4Mb 

coarse material was found only, in samples collected tjver at period 

of a few days during the last week of March 1940. :

The sediment loads measured in Moore Creek above Thorn Creek, 

on. the other handi consisted almost entirely of fine material. Graphs 

of siae analyses in figures 11 and 12 show that from 45 to 55 percent of 

the material in samples collected at this station during the spring 

runoff of 1939 and 1940 consists of particles less than 0.005,iailliiaeter 

in diameter and that from 85 to 95 percent of the material consisted of 

particles less than 0,050 millimeter in diameter. Material consisting 

of particles lesar than 0.005 millimeter in diameter has been classified 

as clay by tl*0 former Bureau of Soils, and is so fine that it does atsfe 

settle readily, evea in reservoirs. There was a period of 3 dr 4 days! 

during the last week off March 1940 corresponding to the period j@f 

maximum discharge when the sediment concentrations in bottom 

samples at the station on Moore Creek above Thorn Creek were from
32 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

Monthly sediment loads in tons measured at stations near Idaho City

«

1939 

January.. ____________

February _ __________

April ___ ____ .........

May _ ___ .- .....

Total....................

July .. ...'_ '

September- __________

October. __ ____ .

November.. __________

TotaL.. ._

1940 

January _____________

February..- ________ .'.._

March, _________ __

April ________ ______

May. _____ _______ .

June. _____ _____ 1 __

Total..... ............

Total-... ... .........

Moore 

Greet 

above 

Granite 

Creek

2.3

12

2,730

1,540

720

23

5,030

9.2

2 7

9 ft

3.2

8.2

14

47

19

170

9 7df\

2,360

928 '

30

6,250

11 ' 300

Granite 

' Creek

0.3

2.3

o nfin

802

68

.8

2,930

.3

0

.3

.2

.5

1.6

3.1

11

413

1,220

272

11

.8

I

Qort

A OCA

Bannock 

Creek

0.09

.5

1.4

7.7

3.2

.8

14

.2

.08

.1

.09

.1

.5

1.1

.5

1.8

443

282

1.1

.4

79O

7d4

Pine

 Creek

.0.9

1:6

364

220

1.4

.2

588

.06

-.04

.1

.08

.06

.4

.7

1.0-

366

5,780

1,130

71

15

7,350

7,940

Elk 

, Creek

2.2

8.1

2,950

2,220

2,200

1,710

9,090

' 615 104-

215

701

351

736

2,720

365

141

661

1,220

811

102

3,300 

15,100

Total

5.8

24

8,110

4,790

2,990

1,730

17,600

625

107 '225

705

360

752

2,770. *

396

1,080

10,800

5,260

1,820

148

19,500

39,900

Moore 

Creek 

above 

Thorn 

Creek

109

1,270

5,330

3,790

4,390

2,240

17,100

716

211

314

474

1,200

1,800

4,720

2,520

3,760

12,400

. 8,520

8,250

3,530

39,000

60,800

three'to five times greater than sediment concentrations in surface 

samples. It is probable that the bottom samples during this period 

contained particles considerably larger than those in surface samples.

It is apparent from the size-analysis data and the information in 

regard to placer-mining activity that only a small part of the actual 

material carried past the stations above Idaho City was measured at 

the station on Moore Creek above Thorn Creek. Most o£ the coarse 

sediment carried past the upper stations was deposited in the deep 

pools behind rock dikes formed by tailings from mining operations. 

(See pi. 7 A and B.) These deep pools act as settling basins because of 

the low velocity through them. The bulk of the fine material carried 

past the station on Moore Creek above Thorn Creek resulted from 

mining operations within the area of placers.

Most of the sediment passing the station on Moore Creek above 

Thorn Creek during 1939 and 1940 was too fine to settle out appreciably in the larger irrigation canals. There is reason to believe, 

however, that during earlier years a large amount of coarse sediment 

was carried downstream and was eventually discharged into the Boise 

River. During future years, when the spring runoff is greater than 

that measured in 1939 and 1940, it is probable that the loads of coarse 

sediment carried past the station on Moore Creek above Thorn Creek-
100

80

70

60

50

40 

...

30

20

10

0.001 .01 

PARTICLE SIZE IN MILLIMET

CLAY SILT

VERY FINE 

SAND

FINE SAND

M

U.S.BUREAU OF SOILS CLASSIFICATION

. Size analyses of sediment carried past five gaging stations near Id
WEIGHT BY FINER PERCENT 

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aonvnosia ONV asioa Nisva

.^ -fofrlfea
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1C48 PLATE 6

A. HORIZONTAL SAMPLER FOR COLLECTING INTEGRATED SAMPLES FROM FOOTBRIDGE. 

B. SAMPLER USED FOR COLLECTING INTEGRATED SAMPLES FROM OVERFALL SECTION.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1048 PLATE 7

A. DREDGE TAILINGS FROM PLACER MINING ON MOORE CREEK BELOW IDAHO CITY.

B. SHALLOW OUTLET FROM DEEP POOL IN PLACERED AREA ON MOORE CREEK BELOW

IDAHO CFTi.
! Li "' : ' ! " ' ' ' ' ' *f> * 'w^/M'iiuyife^rg^^than febie^ iheasured '^uring.'the j|eMa 'bf^this

large but unmeasured loads of 

^i miles below : the station above Thortf0reek

ihe Grinies 

bion 'arid for

Nb'sedinienjt or stream-flow measuring 'station

. was 'estafelSned oft* Grimes Creek ' Bi* it£ tributaries, and therefore no 

'dsliinkte ckn;be made of : the sediment contributed by that stream. 

Hbweveiythe sediment content of a few samples collected at irregular 

Intervals from Grimes C^eek just above its mouth, the appearane^ of 

! the" water ui the twq streams during the spring runoff periods, and the 

, presence of la'rge deposit's of sand hi Grimes Creek and in Moore Creels: 

.below the junction, contrasted with the sand-free channel ui Moore 

Creek above1 Grimes Creek, all suggest that the sediment toads 

earned rnt© Moore Creels ftbtidj, Grimes Creek during the investigation 

'may have been larger than the loads measured 'at the station on Moore 

Creek above Thprn Creek, and tha't the material was con§iderj|Bly ccJai'ser, ' ' .-,< -. ^

SEDIMENT LOADS MBAJ8UBED ABOVB AND BBLOW ABBOW BOOK

-- ..; ,- BAM ... l

T6tpls of isediment loads measured at stations abdye and below 

I$pck Dain fo,r 6-month periods are given in, the table below. 

lieye1 Vas no sedinieiit-ineasuring station on tlje Soufptt Fork of 

the Boise Biver,' which inters Arrow Kock Eeservroic 4 mUe^ abbre 

the dam, br 6n other tributarie^ that are reported to carry large sediinent loads,, this' stiin of thg totals given for th§ three stations above 

tte dam does not represent tlie total sedhnent entering the reservoir. 

l*ne figured for ^he Bowling ranch station do show, Jib^ever, that 

during th? January to June periods ol 1989 and 1940 t!}e sediment 

loads measured at that station were very much legs than the sum of 

thej meastired loads entering the reservoir.

8«Mtoent loads abeve and Mow Arrow Rock Gam .-

 : . ' . ' > ".-{ ' ' ' > ' .' :!;: 

Period

, < i .-i ' ' ''?'; : »i' ' . T -- ."'.' -

January-June 1^9....... _________ , _______ .. ,. ...... I«ly-I>e<seniberl93ft. ^j.^ ,,.-^1^ --uiu - .u *-. i. .

. ' TotaL.,_--_....l.'....;_.__.,.., '.,... ...,. ............. .

- ..'._. "]. :- ,/ i >! »' ' ,

1 l

tuT($6 St&tfolw aliove Arrow Bock Dam. 

(toas) > ;

80,600

1,860

07 400

179.800

Lo^dsfor 

?Boiee Elver' 

at Bowting. 

ranck below 

Awow Book 

Daps, (torn)

13,100

; >'i >.i &W

,,/,. ,'5;<f

45,730

i ; , > '» | '

Arrow Bock. at Arrow Bock Beaervok,
36 DISCHARGE AND SEDIMENT, BQJSE RIVER BASIN

Size Analyses were made on four integrated samples of suspended 

sediment collected on May 11,1940, from the Boise River near Twin 

Springs. Results of two of the analyses representing samples collected 

near the left bank and the right bank are shown by curves A and B, 

respectively, in figure 13. The curves show that a larger proportion 

of coarse sediment was carried near the right bank at the time the 

samples were collected. The suspended-sediment concentration was 

192 parts per million at the sampling point near the left bank and 530 

parts per million at the sampling point near the right bank. Higher 

concentrations were more frequently observed near the right bank 

than near the left.

Size analyses of two sets of integrated stimples collected on April 

1, 1940, from Cottonwood Creek are represented by curves C and D in 

figure 13. Curve C represents the average analysis of two duplicate 

samples taken in the high-water section, and curve D, the average of 

two duplicate samples taken in the low-water section. Approximately 

50 percent of the sediment particles in both sets of samples was coarser 

than 1.00 millimeter in diameter.

Graphs of size analyses of samples collected from Cottonwood 

Gulch and Grouse Creek during March and April 1929 are shown in 

figure 14. These stations have broad-crested weirs with low-water 

and high-water overfall sections. Curves A and (f represent the 

average particle-size distribution. in samples from the high-water 

sections of Cotton wood Gulch and Grouse Creek, respectively, and 

curves B and D represent the average particle-size distribution in 

. samples from. the low-water sections. Material -from both stations 

was coarse. From 50 to 80 percent consisted of particles greater 

,than Q.50 millimeter in diameter, and from 20 to 60 percent consisted 

of particles greater than 1.00 millimeter in diameter. This material 

was somewhat similar to the sediment collected in samples at .the 

stations above Idaho City, which is represented by curves 3^ C,M> 

and E in figures 11 and 12. Sediment concentrations in the samples 

collected from Cottonwood Gulch, during March and April 1939 

ranged from about 1,000 to 40,000 parts per million and those in Grouse 

Creek, from about 10,000 to 100,000 parts per million. Discharges 

durin'g the same period ranged from about 5 to 18 second-feet in 

Cottonwood Gulch, and from about 19 to 34 second-feet in Grouse 

Creek.

Graphs of size analyses of samples collected from the New York 

Canal in April and May 1939 are shown in figure 15." From 45 to 

80 percent of the material in these samples consisted of particles less 

than 0.020 millimeter in diameter. Graphs of analyses of -samples 

collected in March, April, and May 1940 are shown in figure 16. 

The sediment concentrations in samples represented by ^curves A to D - 

in figure 16 ranged from about 100 to 300 parts per million while
/V . SEDIMENT LOADS » , iJ S7

the concentrations in samples represented by curve E ranged .from 

about 50 to 100 parts per million. Although the concentrations were 

-lower, the average particle sizes were larger during April and May 

than they were in March.

Curves F and Q at the right of figure 16 represent the results of 

analyses of samples of bottom material at the gaging station and 

also of material deposited 0.2 mile below the gage. Curve F is the 

average of four samples collected on June 7 from the bottom of the 

canal at'the gage one-fourth the distance from the right bank (station 

A). Curve G is the average of three samples of material collected 

frqm the large sand .deposit after the canal was drained. It will be 

seen that the material in the two groups of samples consisted of coarse 

material, and that the particles were about of the same size. From 

60 to 80 percent of the material represented by curves F and Q 

consisted of particles greater than 1.00 millimeter-in diameter.

The loads measured at Dowling ranch during the period July to 

December 1939 were greater than the sum of those measured at the 

three upper stations. This increase probably resulted partly from 

fine material brought in by the South Fork and other unmeasured 

tributaries and partly from fine material scoured from the old river 

channel as it was exposed by drawdown in the reservoir. The 

amount of sediment measured at the Dowling ranch station during 

the period July to December was Very small considering that nearly 

500,000 acre-feet of water passed the station during the same 6 months. 

Reservoir levels were not sufficiently'low during the period to permit 

sluicing operations. The average sediment concentration for the 

period was only about 10 parts per million.

SEDIMENT LOADS MEASURED AT 13 STATIONS DURING SPRING 

RUNOFF OF 1939 AND 1940

In 1939 and 1940 the greater part of the sediment load in most of 

the streams was measured during the 5-month period from February 

to June. Appreciable sediment loads measured during the other 

7 months in a few streams resulted largely from placerrmining 

operations.

The sediment loads measured at most of the stations were greater 

during the spring runoff in 1940 than during the spring runoff in 193d, 

although at three of the stations the reverse was true. Loads measured 

at the two locations on Elk Creek are not comparable for the two 

periods because of the difference in drainage areas and ako because 

of large .amounts of sediment added to the creek by mining operations 

just above the station near Idaho City. Loads measured ai the two 

Pine Creek stations are more nearly comparable. The difference in 

drainage areas is slight, and there was little if any placer mining 

above either of the stations during the periods of operation.
IOO

90

80

70

CD

tu

20

to

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A. BOISE RIVER NEAR TWIN SPRINGS, ' 

NEAR LEFT BANK

B. -BOISE RIVER NEAR TWIN SPRINGS, 

NEAR RIGHT BANK -

C. COTTOWWOOD CREEK, HK5H-WATE.R SECTION 

D. ~COTTONWOOD CREEK, LOW-WATE* SECTION

PARTICLE SIZE Hsl MILLIMETERS

CLAY SILT

VERY FINE 

SAND

FINE SAND ME

SA

U.S. BUREAU $F SOILS CLASSIFICATION 

18.- Size analyses 9! sedbntet e&trip$, by B<rfse ,Siver near Twte Spring and B
WEIGHT BY' FINER 

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A. MARCH 2 

B. MARCH 9 

C. MARCH IS 

D. APRIL 2 

E. APR. 20- MAY 24 (AV. 5 SAM

F. BOTTOM MATERIAL JUNE 7 

6. DEPOSITED MATERIAL SEPT

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PARTICLE- SIZE IN MILLIMET

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U.S.BUREAU OF SOILS CLASSIFICATION

FIOTTEE 16. Stee analyses of sediment carried by the New York Ca
42 DISCHARGE AND' SEMMBNiy BOISE RIVER BASIN » 

loads measwed during spring runoff of 1BS6 and 1&4& February- June

Station

Boise River at Dowling ranch _____________

firfkTtltfl fJroalr

Pine Creek near Idaho City . 

Elk Creek near Idaho City __ ._,..-

Elk Cieek above Gold HD1 Placer diversion _ ....

Cottonwood 3* Gulch at Boise... _._£. __ . _______

1939 '

Tons

51,900 

113,100 

186,600 

716 

27,700 

15,020 

117,000 

2,930 

14 1687

19,090

138,600 

24,800

Tons per 

square mile

63 

15.0 123 

33 

3,460 

1136 

H43 

610 

3.1 190

1408

1,550

1940

T«

09,100 

127,500 

1 114, WO 

8,050 19,900- 

16,280 

136,500 

1,050 

728

17,350

2,820 

182,400 

15,000

Tons per 

square mite

-88

376 

2,490

1307 

406 

162

11,266

215

"938

i Sediment loads affected by appreciable regulation or diversion above station.

The largest sediment loads per unit of drainage area were measured 

in Grouse Creek during periods of spring runoif of 1939 and 1940. 

They were more than twice as large as the, load per square mile measured at any pther station during each of those years. The second 

largest loads per square mile were measured in Cottonwood Gulch 

in 1939 and in Pine Creek in 1940. The smallest loads per square 

mile were measured in Bannock Creek during, 1939 and in the Boise 

River at Dowling ranch in 1940. The loads measured at Dowling 

ranch are of little significance, however, because the station is below 

Arrow Rock Dam. The smallest load per square mile during 1940 at 

stations unaffected or only slightly affected by regulation or diversions 

was measured in the Boise River near Twin Springs. i

SEDIMENT LOADS MEASURED AT 13 STATIONS DURING 18-MONTH 

PERIOD OP INVESTIGATION

The total loads of sediment measured at all of, the stations during 

the 18 months of the investigation are given in. the table below. 

Inasmuch ,as the loads at many of the staMons were affected by regulation, diversion, or other artificial means the loads asqpressed -in. tons 

per square mile are not comparable. The largest loads per. square mile 

during the 18-month period were'measured in Grouse Creek and the 

second largest in Cottonwood Gulch. The smallest loads per squate 

mile for those streams relatively unaffected by regulation, diversion, 

or othef artificial means, were measured in the Boise River near 

Twin Springs. ~ r
. &edtimnt Ipads measured during 18 months ended June 80, 1940

Station

QrouseOKeek-. - - .. . - _ -

Granite Cssek. , ... . ... __ ..... ........

J5& Gteelc B6&£ Z&aho Oity ^» '

1 Tons"

123,400

146,700

» 210, 000

-. 8,780

47,600 uij'&eo. 360,800'

4890 ,743 tS95

*7,35Q

312,300

2,820

1 128, 500

39,800

Tens per 

square mile

149 121

156

410

5,950 3305

n *511

1,020

165

*92

*l,20e »552

215

2,490

i Sediment loads affected by regulation above station,

* Sediment loads affected by diversions or minor regulation above station. 

» Station operand Jan. 16,1939, to Feb. 12,1940.

* Station operated Feb; 13 to June 30,1940.

1 Station operated Jan. 20, 1939, to Feb. 4,1940.; > .

8 Station operated Feb. 4 td Jane 30,1940.

VARIATION»IN«E3XIMENT CONCENTRATION ANB STBEAM 

VELOCITY IN THE NEW YORK CANAL

During the spring runoff period of 1940, at the time sediment 

samples were collected, BO series of velocity measurements were made 

at the stream-gaging station on the N ew Y ork Canal. These measurements were eaade at 12 points in the cross section corresponding to the 

sediment-sampling points. The velocity was measured at each of 4 

points' in the vertical surface, mid-depth, 0.5 to 1.0 foot off the 

bottom, and 0.2 foot off the bottom immediately after which, sediment samples were collected at those points with the Tait-Biapkley 

sampler. Similar procedure was followed at each of 2 other vertical 

sections. The 3 vertical measuring sections were approximately 

one-fourth, one-half, and three-fourths the distance across the canal.

Although there was undoubtedly sosnae fluctuation in sediment 

concentration from instant to instant at each measuring point, in 

general the concentrations determined in the samples probably 

represent very nearly the concentrations at the measuring points at 

the tame the velocity measurements were made.

The results of measurements of velocity and sediment concentrations are given in the accompanying table. Velocities near the surface and bottom and at two intermediate points have been plotted 

against sediment concentrations and are shown in plate 8. The 

sediment concentrations of from 3,000 to 3,250 parts per million on 

March 27 were the highest measured during the 30 series of measurements. Variations hi sediment concentration with depth for four 

samDling periods are shown in figure 17,

758529-r48 I
44 DISCHARGE AND SE&IMENT, B0JB& BIVER BASiN

0

s 2

8 

10 7

0 

2

S*

0

8

'°2

MARCH 26, 1940-STATION B -

"\

f

/

VVXyO^Jsj^^i

'00 800 900 

SEDIMENT CONCENTRj

MARCH 30, 1940-STATION A

 L 

00

SS

300 400 

SEDIMENT CONCENTR

0

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Ul

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Z '

i 6

B

'°3, 

iTION IN

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LU

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XTION IK

MARCH 27, 1940-STATION C

^V

\^^^-^

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POO 3,100 3,200 

RftRTS PER MILLION

MAY 25, 1940-STATION B

\,

"^"w*.

S88888&88! ^^*/SA^^^A^ R>

> 100 200 

1 FttRTS PER MILLION

FIGURE 17. Variation in sediment concentration with depth in New York Canal at different times during

spring runoff of 1940.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1048 PLATE 8

7 

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SEDIMENT CONCENTRATION IN PARTS PER MILLION 758529 o - 48 (Face p. 44)

SEDIMENT CONCENTRATION AND VELOCITY IN NEW YORK CANAL DURING SPRING RUNOFF OF 1940
\

, Velocities and>$&£im&nt ceseenirafo'ows at various

near Barber

- 45

in the ;Neiff York Canal

Date

19$

Feb. 9.........................

'

Feb. 11 __ ..^ _ *-..-._-_ .-

_

Feb. 13 __ .. __ - _____ .

*

Feb. 14.............-. .....

J-eb. 26-.....-.... .. ....

, ^

Time

9:30 a. m.. ________

*

10:40 a. m... _______ .

10:30 a. m..,._._. ___ .1

,

11:15 a. m .. ...

8:25 a. m..................

 ( "

.Station »

A

B

C

A

B

C

A

B

,

C

A

B

C

t

A

B

C

Depth 

(feet)

0.2

1.4

2.3

2.8

.2

1.4

2.3

2.8

.2

1.4

2.3

2.8

.2

2.4

4.3

4.8

, .2

2.4 4.2'

4.7

.2

2.4

 4.2

4.7

.2

2.4

4.4

4.9

.2

2.4

4.4

4.9

.2

2.4

4.4

4«

.2

2.6

4.7

5.,2

.2

2.5

4.5

5.0

.2

2.5

4.5

5-0

.2

2.4

4.2

4.7

.2

2.3

4.1

4.6

.2

2.3

4.1

4.6

Velocity » 

' (ft. per 

sec.)

3.15

3.31

2.94

2.31

3.22

3.39

2.88

2.35

3.12

3.15

2.69

1.97

4.88

4.62

4.00

3.31

5.23

5.10

4.24

3.87

4.72

4.88

3.83

2.82

4.81

4.67

4.09

3.67

5.35

4.99

4.39

4.00

5.10

4*. 88

4.00

3.52

4.77

4.72

4.00

3.45

5.35

5.49

434

3.91

5.10

5.23

4.19

2.94

4.67

488

3.91

3.39

5.04

4.99

4.48

3.75

4.58

4,67

4.04

3.63

Sediment 

concen-. 

tration 

(p. P. m.)

1 219

226

248

245

250

247

245

243

247

279

248

229

224

239

243

240

225

. 234

236

246

. 225

237

235

234

79

89

102

103

86

73

95

90

89

94

89

96

74

63

65

69

65

62

56

59

62

52

61

55

118

120

115

116

126

. 125

125

132

^ 171

128

121

146

See footnotes at end of table.
46 DISCHARGE AND SEDIMENT, BOISE)RIVER BASIN

Velocities and sediment concentrations at va/ri&m depth$ -in < $« New York

near Barber Continued

\ 

Date

Wlf)

Mar. 6. - ______ - __

Mar. 16 __ ... .-

<

.

;

Mar. 26.. ...... ....'. ...

Mar. 27 . . .

Mar. 28 ...... _ .... _ ....

Time

5 p. m__ _ .....

9 a. m .....................

f

3:55]p. m. __ ...,________

8:40>. m.. ... ..._...__.'.

,

6:29 p. m ..................

v

Station 1

A

B

O

A '

B

C

A

B

i

1 C

A

B

C

A

B

0

(

Depth 

(feet)

0.2

2.0

3.6

4.1

.2

2.0

3.5

4.0

.2

2.0

3.5

4.0

.2

2.4

4.3

4.8

."2

2.4

4.2

4.7

.2

2.4

4.3

4,8

.2

2.8

5.1

5.6

.2

. 2.8

5.0

5.5

.2 2.8'

5.1

5.6

.2

2.8

5.1

5.6

.2

2.8

5.0

5.6

.2

2.8

5.0

5.5

.2

3.2

5.9

6.4

.2

3.1

5.7

6.2

.2

3.2

5.9

6.4

Velocity » , 

fft. per 

sec.)

4.19

4.04

3.43

3.08

4.99

4.67

4.19

3.67

4.67

434

3.67

3.39

4.31

4.36

3.93

3.54

5.07

5.13

4.21

3.88

3.67

5.46

4.81

4.21

3.61

5.96

5.51

4.66

3.98

6.07

5.46

4.29

3.40

5.39 

5.35

4.48

3.91

6.57

6.26

6.10

, 4.29

6.20

5.87

4.82

4.29

5.33

5.16

4.42

4.03

6.37

6.01

5.04

4.28

6.43

5.85

4.71

3.81

Sediment 

concentration 

(p. p. m.)

218

215

224

199

204

214

218

223

212

209

255

228

102

99

103

103

95

103

102

110

109

102

105

109

750

.783

762

779

766

771

, 762

795

781

817

805

800

2,920 

3,090

3,070

3,110

3,040

3,150

3,170

3,240

3,040.

3,080

3,180

3,250

692

i* 73*

760

- 768

687

731

766

788

702

722

739

785

See footnotes at end of table.
ontinued

" *

Date

JftJO

SUM-. 30-.....-.-..._......:....

>;. ! ' ,

i

\

J ,

Apr. 5,_...._....__........_.._

«

Apr. 10 __ ..........

,i

Apr. 13 __ j.. ................

'

%

,

Apr. 17. .A .......... __ .

i

J

.' Time

5:25 p. m _ .

8:15 a. m. _ ; ............

4:25 p. m........: .........

3 p. m . .......

4:15 p. m~. ______ ...

Station 1

A

B

C

,

A

B

C

A

B

C

A

B

0

A

B

0

Depth 

(feet)

0.2

2.8

5.2

5.7

.2

2.8

5.0

5.5

.2

2.8

5.1

5.6

.2

2.2

3.9

4.4

.2

2.2

3.9

4.4

.2

2.2

3.9

4.5

.2

2.0

3.5

4.0

.2

1.9

3.4

3.9

.2

2.0

3.5

4.0

.2

2.0

3.6

4.1

.2

2.0

3.6

4.1

.2

2.1

3.7

4.2

,2

2.8

5.1

5.6

.2

2.8

6.0

5.5

.2

2.8

5.0

5.5

Velocity* 

(ft. war 

sec.)

5.28

4.86

4.13

3.69

6.13

5.34

4.61

4.13

5.80

5.34

4.38

3.69

4.25

4.21

3.54

3.22

5.04

4.98

4,18

3.69

4.66

4.51

3.94

3.24

4.23

4.03

 3.73

3.20

4.71

4.51

4.13

3.61

,4.56

4.25

3.69

3.14

4/42

, 4.23

3.61

3.22

5.10

4.86

4.03

3.69

4.71

4.51

3.71

3.14

6. IE

4.71

406

3.61

«.86*

5.51

4.42

3.77

5.65

5.16

4.13

3.54

Sediment 

eoncentration 

{p» p. m.)

2i9

283

280

312

276

282

302

. 308

282

315

275

304.

116

232

280

289

230

241

305

347

241

215

262

378

100

142

110

143

108

136

118

165

104

143

130

253

139

176

209

224

133

169

201

232

140

199

207

27

74

91

U7

151

66

117

llfi

186

126

82

123

185

See footnotes at end of table.
48 DISCHARGE. AND SEDIMENT, BOISE RIVIB BASIN

Velocities and sediment concentrations at various depths- in the New. York Can&l

near Barber Continued

Date

1940 

Apr. 20 ... .

,

Apr. ^.. ......................

Apr. 27. . _.. . 

May 1 - '

v

May S..........................

Time

8:25 a.m.. ...... ___ . 

3:50 p. m ___ ............ 

.....do.. . -....-....

.

8:20 a. m... _____ .

Station »

A

B,

C

A 

B 

C 

A 

B 

C 

A

B

C

A. 

B 

C

i

Depth 

(feet)

0.2

3.2 

6.0 

6.5

.2

3.2

5.9

6.4

.2

3 2

6.0

6.5

.2

» 4.0 

7.5 

8.0

.2

4.0 

7.4 

7.9

.2

4.0 

7.4 

7.9

.2

4.2 

8.0 

8.5

.2 4.2' 

7.9 

8.4

.2 

4.2 

8.0

8.5

.2

3.8

7.0 

7.5

.2

3.7

6.9

7.4

.2

3.7

6 9

7.4

.2 

4.1

7.7 

8.2

.2 

4.0

7.5 

8.0

.2 

4.0 

7.6 

8.1

\

Velocity * 

(ft. per 

sec.)

5.60

5.28 

4.33 

3.73

6.31'

5.91

4.81

4.42

6.01

5.75

4.71

3.73

6.01 

5.75 

4.61 

4.13

6.98 

.6.63 

5.41 

4.66

6.56 

6.43 

4.92 

3.98

6.19 

.6.01 

4.66 

3.98

6.91 

6.91 

5.41 

4.71

6.77 

6.49 

4.98 

4.23

5.70

5.56 

4.76 

3.90

6.77

6.25

5.16

6.37

5.91

4.81

4.18

5.65 

5.91 

4.56 

3.85

6.91 

6.91 

5.16 

4.76

6.77 

6.43 

4.86 

4.08

Sediment 

concentration 

(p. p. m.)

»53

81 

134 

171

. 42 

73

216 

451

69 

157 

191 

1,520

58 

93 

157 (4)

84 

135 

296 

339

104 

145 

271 

530

88 

179 

273 

316

947

54 

150 

333

54 

86 

189 

350

45 

77 

189 

559

123 

58 

109 

193

See footnotes at end of table.
SBDIMSNT OONCMNrTRASPKHSF AND SCTMliC 49

Velocities and sediment concentrations at various depths in the New York Canal

near Barber Coatinued

1 

Date

1940 May 11.......-:-. . .

f

,

May 15. .. 

May 18...-.... .

x ' 

'

May 22 ..................

,

'

May 25... .

Time

3:05 p. m . . .......

-

9 a. m ___ . ____ ......

'

8:30 a. m _ , __ ......

3:50 p. m _________ .

4 p. m... _ . __ ......

Station i

A

B

C

"A

B

O

A.

B

O

A

B

0

A

'

B

Depth 

(feet)

0.2

4.3

7.6

. 8.6

.2

4.2

7.5

8.5

.2

4.2

7.5

8.5

,2

4.3

7.6

8.6

.2

4.2

7.5

8.5

.2

4.2

7.5

8.6

.2

4.2

7.5

8.5

.2

4.2

7.4

8.4

.2

4.2

7.5

8.5

.2

4.3

8.1

^ 8.6

.2

4.2

8.0

8.5

.2

4.2

. 8.0

8.6

.2

4.3

7.6

8.1

8.6

.2

4.2

7.5

8.0

8,<f

Velocity 3 

(ft. per, 

see.)

S.70

5.75

4.81

3.40

7.06

6.84

5.91

4.71

6.56

6.63

5.16

3.94

5.86

5.91

4.71

3.64

6.84

7.14

5.65

4.61

6.43

6.43

5.16

3.65

&96

5.80

481

3.47

6.98

6.77

5.61

461

6.43

6.25

481

a si

5.86

5.91

433

3.65

6. 63

6*63

5.22

423

' 6.43

6.13

5.34

3.73

5.91

5.65

4.71

466

4.13

6.63

6.63

5.22

498

,.. .4,61

Sediment 

concentration 

(p. p. m.)

75

78

172

Ml

60

71

" 175

386

'65

78

99

160

48

61

101

645

37

48

144

107

36

59

59

169

35

5269'

169

34

39

116

349

41

66

78

155

42

70

299

566

38

43

4T

146

42

51

93

222

34

41 '10$

76

540

33

31

44

52

. . 71

See footnotes at end of table.
t* and*8edi*nttnt &meentrc^i<ma e& various depths fo, 

near

Date

19$

May 25.......i...............

May 29.... .... . ......

June 5. _ ... _______ * ...

,

V

June 121 _. _.. ....4...

June 19:. _ , _ . ____ ._« _

r

H

June 26 _____________

Time

4p. m.. T 

4:16 p. m ................. 1

,

5:05 p. m _ T ..............

6 p. m , . .

i

5p. m .....................

,

4:80 p. *p. ..... ... .... .... ..

Station '

C

A

B

C

A

B

C

A

B

C

'A

B

O

A

\

. Depth 

(feet)

0.2

4.3

7.6

8.1

8.6

.2

4.2

7.7

8.7

.2

4.3

7.6

8.6

 2

4.4

7.7

8.7

.2

4.4

8.4

8.9

.2

4.4

8.2

8.7

.2

4.4

8.4

8.9

.2

3.6

6.7

7.2

.2

3.5

6.5

^ 7.0

.2

3.6

6.6

7.1

'.2

3.6

6.8

7.3

.2

3.6

6.7

7.2

.2

3.6

6.8

7.8

.2

3.7

6.9

7.4

Velocity * 

(ft. sen 

sec.)

6.13

6.19

4.71

4.56

3.69

5.80

5.70

4.71

3.54

6.91

6.49

,5.65

'4.6f

5.91

6.13

- 4.76

3.77

5.86

5.75

4.51

'2.33

6.63

6.83

4.81

4.51

6.19

6.25

4.13

3.50

5.05

5.30

4,00

«2.78

6.10

5.78

4.48

4.09

' 6.88

5.49

4.09

3.18

5.36

5.34

3.68

3.52

6.10

5.83

4.58

4.34

5.73

5.68

4.34

3.52

5.63

5.83

4.39

3.52

Sediment 

concentration 

(p. p. m.)

',! 89

33

35

41

51

24

24

49

 72

30

27

31

147

48

40

64

' 123

41

49

122

'25,000

23

25

24

40

24

23

25

27

34

221

54

'1,180

31

18/

41

68

' 17

16

18

22

18

11

27

339

9

9

12

19

«

10

r

11

10

16

14

« 448, 000

See footnotes at end of table.
Velocities c^nd sediment emcentratio^ & wri&us depths in tke New Yorkv Canalnear Barber Continued

Bate

19$

June 26 ..

\

1 <

Time

4:20 p. m. ........ .T ........

Station i

B

C

Depth 

(feet)

0.2

3.6

6.8

7.3

.2

3.7

6.9

7-4

Velocity* 

(ft. pec 

sec.)

.'

6.21

5.88

4.99

4.14

&17

5.30

3.67

2.96

Sediment 

 oeaeen* 

tration 

(p. p. m.)

12

9

7

24

8

5

5

7

1 A, B, and C approximately one-fourth, one-half, and three-fourths the distance across the canal.

* Velocity corresponding to bottom samples measured about 0.2 foot above bottom.

 i Composites of A, B, and C; size analyses made ol composites. '

* Sample lost.

' Low velocity and heavy sediment, result of sand wave.

 High sedident content, result of sand wave.

Size analyses made on two series of samples, one collected on April 

20 and the other on May 1, are shown graphically in figures 18 and 19, 

respectively. For the series of samples collected on April 20 more 

than 60 percent of the sediment in surface samples consisted of 

particles less than 0.020 millimeter in diameter. The sediment 

became coarser with increasing depth and in the bottom samples 75 

.percent was larger than 0.050 millimeter. The composition of the 

sediment in the series of samples collected on May 1 was somewhat 

similar to the composition in the series collected on April 20. Although size analyses were not made on other samples collected at 

times of velocity measurements, analyses were made of several series 

of point samples collected during the period March 2 to May 24,1940. 

These analyses indicate that the sediment transported during March 

and the early part of April was finer than that carried during the 

latter part of April and during May.

The plots in ^late 8 show that there is no relation between velocity 

and sediment concentration for the size and concentration of material 

transported^. It i& obvious that the water was not saturated with 

suspended sediment for the velocities encountered, and since the 

canal bottom consisted ol concrete instead of sand there was no way 

in whichtthe sediment load in the canal might be increased except 

as it moved beneath the head gates at Diversion Dam. There were 

undoubtedly local areas of saturation along the bottom! of the canal. 

at times when coarse sand was transported in the form of dunes. 

It. wa£ not possible, however, to make reliable measurements of 

velocity at points next to the bottom during the passage of the dunes.
DISCHARGE AND SEDIMENT, BOISE RIVER BASIN 

1H9I3M A8 aSSyVOO JLN3083d

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PARTICLE SIZE IN MILLIMETE

CLAY - SILT

VERY FINE 

SAND

FINE SAND 

U.S. BUREAU OF SOILS CLASSIFICATION 

FISUSE 19. 8 ize analyses of sediment carried at varying depths 
...-. ' ^

54 DI&CHABGE ANB SEDIMENT, BOISE BIYEB B^SIl* , ' /

BJ|D LOAD

BED LOAD IN THE NEW TORE CANAL

The New York Canal diverts water from the Boise River at Diversion Dam 8 miles downstream from Moore Creek. The dam creates 

a pool from 2 to 3 miles long, which acts as a settling basin for the 

coarser sediments carried by the river. The pool has become so filled 

with sediment that the storage capacity is negligible. The deposited 

material in the pool is always a potential source of sediment in the. 

New York Canal.

During the spring and summer of 1939 very little coarse material 

was found in bottom samples collected from the canal. The results of 

size analyses of three sets of point samples, each consisting of 

surface, mid-depth, and bottom samples collected during April and 

May 1939, for which graphs are shown in figure 15, show that about 

70 percent of the material in the samples consisted of particles less / 

than 0.050 millimeter in diameter. The concentration of sediment 

in bottom samples on which no size analyses were made* usually did not greatly exceed the concentration of sediments carried in 

suspension. When the canal was drained in September 1939 no material was found in the lined sections for a distance of 3 miles below 

Diversion Dam. Practically no material was found in the wide 

section 0.2 mile below the gaging station, where sand always deposits 

'"if any appreciable amount is carried past the head gates at Diversion 

Dam.

During April 1940 coarse sand was observed occasionally in bottom , 

samples collected at the gaging stations. The sand appeared to be 

moving along the bottom at irregular intervals since it was found in 

some samples but not in others. During May and June sand was 

found more frequently than during April, particularly at the sampling s 

point one-fourth of the distance from the right bank.

Results of observations suggest that the sand is rolled or skipped 

along the bottom of the canal in much the same manner as sand is 

moved in dunes by the wind. It seems probable that the moving 

sand particles were at times in suspension and at times rolling. The ~ 

entire movement appears to have taken place within the zone of 

saltation which is described by Gilbert 6 as follows: "Some particles 

of, the bed slide, many roll, the multitude make short skips or leaps, 

the process being called saltation. Saltation grades into suspension. 

When particles of many sizes are moved together the large ones are 

rolled." The movement of sand in dunes is a form of bed load.

 'Gilbert, G. K,, The transportation of debris by running water: U. 8. Geol. Survey Prof. Paper 86, p. II, 

1014.
'4ft6 month of Jucie iWfi five series of ofcs^atloBus of the 

movement of sand chines-were made from the bridge at the gaging 

station: -Bottom samples were taken every 2 to 4 minutes at stations 

A, B, and C, these stations corresponding to distances about, onefourth/ one-half, and three-fourths of the distance from the right 

bank. After it was founcf that very little sand was being carried past 

stations B and C, most of the sampling was done at station A.

Point samples were taken with the Tait-Bincldey sampler which was 

fastened to a 15-foot length of %-inch pipe. In order to hold the pipe 

in a vertical position the sampler was fastened to a stay line. The 

sampler was lowered t6 the bottom and held in the open position from 

2 to 3 seconds, then the cord was pulled to close it.

Sand was observed on the bottom at irregular intervals. The 

presence or absence of sand could be determined fairly definitely by 

noting the depth at which the bottom was reached. By careful 

sounding the approximate width and height of the dunes could be 

determined. The widths usually varied from about 2 to 6 feet but 

occasionally widths of 8 feet were observed. The heights were less 

than 0.5 foot. The lengths of the dunes could be determined only 

with'respect to the time it took them to pass the sampling point. 

Ordinarily the dunes passed the sampling point in from 2 to 4 minutes. 

All the data obtained during the five series of observations are given

in the following table.

i ^

Variations in sediment concentration in bottom samples and approximate width of 

sand dunes in the New York Canal

Date

1940 

June 7 

«

J

Timei 

(P. m.)

2:20 

2:22 

2:24 

2:26 

2:28 

2:30 

2:32 

2:34 

2:36 

2:38 

2:40 

2:42 

2:44 

2:46 

2:48 

2:50 

2:52 

2:54 

2:56 

2:58 

3:00 

3:02 

3:04

Sediment concentration in parts per million at the following 

stations 2

A

8,930 

240 

145 

35 

71 

49 

63 

272 

1,630 

10,400 

352 

266,090 

3,370 

58 

338 

3d 

190 

47 

79 

63 

105 

106 

326

B

81

38

68

128

39

62

82

 43

144

34

C

60

-28

34

33

33

35

30

34

36

37

Approximate 

width 

tit 

dune . 

(feet)

Date

1940 

June 7 .....

Time« 

(p.m.)

3:06 

3:08 

3:10 

3:12 

3:14 

3:16 

3:18 

3:20 

3:22 

3:24 

3:26 

3:28 

3:30 

3:32 

3:34 

3:36 

3:38 

3:40 

3:42 

3:44 

3:46 

3:48 

3:50

Sediment concentration in parts per million at the following 

stations *

A

766 

TjBl 

109 

866 

4,570 

289 

328,000 

140 

308 

425 

120 

68 

113 

229 

'185,000 

227 

3185,000 

654 

,144 

286 

82 

66 

372

B

50

71

70

148

48

101

71

56

103

C

43

33

>

44

45

41

42

50

47

46

Approximate 

width of 

done 

(feet)

-

See footnotes at end of table.
56 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

Variations in sediment concentration-in bottom samples and approximate width of 

sand dunes in the New York Canal Continued

Date

mo

June 7 ._

Timei 

(P. m.)

3:52 

3:54 

3:56 

3:58 

4:00 

4:02 

4:04 

4:06 

4:08 

4:10 

4:12 

4:14 

4:16 

4:18 

4:20 

4:22 

4:24 

4:26 

4:28 

4:30 

4:32 

4:34 

4:38 

4:40 

4:42 

4:44 

4:46 

4:48 

4:50 

4:52 

4:54 

4:56 

4:58 

5:00 

5:02 

5:04 

5:06 

5:08 

1 5:10 

5:12 

' 5:14 

5:16 

5:18

5:20

5:22 

5:24 

5:26 

5:28 

5:30 

5:32

~5:34 

5:36 

5:38 

5:40 

5:42 

5:44 

5:46 

5:48 

5:50 

5:52 

5:54 

5:56 

5:58 

6:00 

6:02 

6:04 

6:06

Sediment concentration jn parts per million at the following

stations *

A

49 

81 

55 

296 

76 

46 

54 

168 

109 

102 

764 

198 

348 

174 

734 

5,160 

74 

121 

55 

177 

83 

135 

245 

154 

>136 

167 

147 

87 

Broken 

412 

3,850 

17,400 

16,600 

124 

993 

228,000 

5,330 

- 198 

84,000 

2,150 

130 

278 

No 

sample 

No 

sample 

12,400 

80 

96 

248 

2,500 

No 

sample 

121 

160 

543 

14,400 

15,100 

51,200 

235 

89 

248 

65 

77 

312 

139 

135 

536 

49,000 

No 

samnle

B

57

44

161

94

160

74

74

97

59

72

204

161

141

707

178

176

117

395

33

115

1,740

68

.264

73

315

 v- 61

137

C

31

35

42

33

29

37

30

31

36

36

41

39

25

32

23

26

42

39

18

18

Broken

28

29

32

34

27

30

Approximate 

width 

of 

dune 

(feet)

.<

^

*

Date

1940 

June 7...--

June 12. ... 

*

Timei 

(P. m.)

6:08 

6:10 

6:12 

6:14 

6:16 

6:18 

6:20 

2:10 

2:12 

2:14 

2:16 

2:18 

2:20

2:22 

2:26 

2:30 

2:34 

2:36 

2:38 

2:40 

2:44 

2:46 

2:50 

2:54 

2:56 

3:00 

3:02 

3:04 

3:08 

3:10 

3:14 

3:16 

3:20 

3:22 

3:24 

3:26 

3:28 

3:30 

3:32 

3:34 

3:38 

3:40 

3:42 

3:44 

3:46 

3:48 

3:50 

3:54 

3:56 

3:58 

4:00 

4:02 

4:64 

4:06 

4:08 

4:10 

4:14 

4:30 

4:32 

4:40 

4:42 

4:44 

4:46 

4:52 

5.-02 

5:06 

5:08 

5:20 

5:22 

5:24

Sediment concentration in parts per million at the following 

stations 2

A

100 

53 

79 

290 

198 

558 

213 

6,840 

142,000 

114 

86 

103 

No 

sample 

- 109 

159 

546 

479 

2,450 

7,200 

203 

297 

821 

14,500 

3,580 

198 

76 

391 

363 

9,340 

1,120 

724 

412 

55 

749 

132 

1,050 

80,300 

316,000 

127 

16,300 

2,070 

98 

5,410 

306 

93,500 

1,270 

392 

48,200 

561 

403 

"999 

141 

460 

6,79ft 

132 

83 

795 

45 

286 

220,000 

3,940 

805 

16,600 

1,210 

32 

973 

1,260 

113 

7,160 

79

B

87

70

47 

152

64

140 

1,370 

194

64 104

521 

72

134

- 208

428 

133

38

56

330

72

219

47

34 

149

40

111

57 

69 

1,350 

50 

34

250

22

169

33

134

C

32

39

%

32

23

15

15

15

24

24

24

23

23

23

24

24

24

24

22

Approximate 

width 

of 

dune 

(feet)

f

See footnotes at end of table.
Variations in sediment concentration in bottom samples and approximate 

setnd dunes in the New York Canal Continued

of

Date

1940 

June 12....

June 19. ...

» 

June 26 _ .

Timei 

(p. m.)

5:28 

5:34 

5:36 

5:38 

5:40 

5:42 

5:44 

5:46 

5:50 

5:52 

, ,6:00 

6:02 

6:04 

6:06 

6:08 

6:10 

6:12 

1:30 

1:34 

1:36 

1:38 

1:42 

1:44 

1:50 

1:58 

2:00 

2:10 

2:18 

2:20 

2:24 

2:26 

2:28 

2:30 

2:32 

2:40 

2:50 

3:04 

3:06 

3:08 

3:10 

3:22 

3:26 

3:28 

3:30 

3:32 

3:36 

3:50 

4*2 

4:04 

4:10 

4:30 

4:32 

4:34 

4:36 

4:46 

4:48 

4:50 

4:52 

5:10 

5:12 

5:14 

5:16 

5:20 

5:24 

5:26 

5:30 

1:05 

1:07 

1:09 

1:11 

1:13

Sedtmeat concentration In parts per million at the following 

stations a

A

636 

2,640 

25,600 

108 

'53 

393 

5,170 

251 

724 

65 

47 

82 

1,010 

26,900 

248 

282,000 

693 

97 

5,050 

284 

262 

2,680 

407 

18 

6,230 

2,240 

214 

513, 000 

140 

773 

585 

,329 

«,090 

543 

397 

157 

19,900 

320 

153 

112 

157 

2,060 

331,000 

795 

264 

119 

52 

1,000 

374 

J07 

87 

430,000 

8,270 

561 

460 

267,000 

763 

182 

81 

13,500 

347 

236 

30 

274,000 

589 

93 

27,100 

115 

24 

273 

1,600

B

675

59

89

52

H4

274

61

22

22

22

22 

22

22

69 

69 

69 

69

69

78

78 

78

47 

47

47

11

11 

11

11 

22

C

20

20

20

20

12

/12

12

12

12

 12

10

10

10 

10

10

10

11

11 

8

Ap-. proximate 

width 

of 

dune 

(feet)

4

6

' 2

3

5

. ..4

4

6

Date

1940 

June 26.-.

 Julyl. .

Timei 

(p. m.)

1:15 

1:17 

1:19 

1:21 

1:23 

1:25 

1:45 

1:47 

1:49 

1:51 

1:53 

2:01 

2:05 

2:07 

2:09 

2:13 

2:23 

2:25 

2:31 

2:43 

2:45 

2:51 

3:03 

3:05 

3:07 

3:19 

3:23 

3:25 

3:27 

3:29 

3:31 

3:33 

3:37 

3:45 

3:47 

3:49 

3:51 

3:55 

3:57 

4:05 

4:07 

4:09 

4:11 

4:19 

4:21 

4:23 

4;29 

4:33 

4:35 

4:37 

4:41 

4:45 

4:49 

4:55 

4:57 

5:01 

5:03 

5:05 

5:07 

5:09 

2:10 

2:12 

2:14 

2:16 

2:18 

2:20 

2:30 

2:5(7 

2:52 

2:56 

2:58

Sediment concentration ia parts per million at the following

stations 3

A

22

35,200 

204 

2,790 

18 

18 

62 

372,000 

176 

368,000 

178 

79 

168 

242,000 

361 

59 

197 

117 

34 

95 

1,700 

953 

1,180 

25,600 

112 

52 

247 

38 

891 

173 

11,200 

353 

469 

19 

411 

239,000 

29 

271 

24,800 

19 

242 

255 

27 

124 

244,000 

69 

49 

272 

5,830 

364 

2,850 

35 

2,680 

1,050 

49 

56 

402 

826 

49 

51 

107 

65,200 

231 

2,240 

2,460 

7,140 

76 

20 

288 

8,200 

1,030

B

22

22 

22

27

27

27

15

15

15

15

15

179

179

179

179

179

76

76

14

14

14 

14

14

C

8 

8

8

V

8

t

8

9

9

9

^

9

9

9

17

17

5

5

5

Ap-. proximate 

width 

of 

dune 

(feet)

8

2

5

3

i

 4

_ ..3

... 4

-....2

 .-2

See footnotes at end of table.
in sediment concentration in fwtiom s&inpk** an£

sand dunes in the Nerit ¥ork Ctf*M»-H(3oatlnt»d /

Date

1940 

July ! .

Timei 

(p.m;.)

1

3:00 

3:02 

3:04 

3:10 

3:14 

3:16 

3:18 

3:30 

3:38 

3:40 

3:44 

3:46 

3:50 

. 4:02 

4:04 

4:06 

4:08 

4:10 

4:12 

4:14 

4:16 

4:20 

4:28 

4:30 

432 

434

Sediment concentration in parts per mil- 

' lion at the following 

stations *

A

4,180 

344,000 

108 

333 

555 

1,430 

47,200 

128 

820 

395 

413 

2,270 

23 

85 

240 

253 

205 

346,000 

14,000 

12,500 

75

i 52 

1 314

5,070 

2,680 

230,000

B

37

37

37

37

37

67

67

67

67

O

5

5

6

6

Ap-. proximate 

width 

of 

dune 

(feet)

4 

3

5

1

.4

Bate

W40 

July 1...1.

Timei 

(P.m.)

436

4:40 

4:44 

4:50 

5:00 

5:02 

5:06 

5:08 

5:10 

5:14 

5:16 

5:18 

5:20 

5:22 

5:24 

~ 5:28 

5:44 

5:48 

5:50 

5:52 

5:54 

5:56 

6:00 

6:06 

6:08 

6:10

SenJiment concentration in parts per million at the following

stations .2

A

164

81 

44ft 

27 

.,130 

103 

1,280 

6,320 

3,510 

272,000 

3,730 

377,000 

190,000 

1,160 

v '679 

121,000 

34 

202 

43 

32S 

3,900 

118 

155 

89,200 

140 

12

B

er

67 

19

19

19

19 

19

19

13

13

0

,

6

6

6

10

Approximate 

width 

of 

duufl 

(feet)

6

i Time reported is for station A; samples collected at stations B and C were collected about J-i and 1 minute, 

respectively, after time of collection at station A.

3 Stations A, B, and O approximately one-fourth, one-half, and three-fourths the distance across eamal, 

measured from right bank. 

Sediment concentrations in the bottom samples ranged from 100 

parts per million or less when there was no sand on the bottom to 

three or four hundred thousand parts per million at the time the dunes 

were passing. The heaviest concentrations were found in samples 

that appear to have been collected at 'the time the downstream face 

of a dune just reached the sampling point. During the process of 

deposition on the downstream face of the 'dune large quantities of 

sand moved into the sampler during the 2 or 3 seconds that it remained 

on the bottom in the open position. The rapid changes in sediment 

concentrations in bottom samples at station A on June 19, 1940-y ate 

shown graphically in figure 20.

The size composition of the material moved in the dunes ^ 

shown by curve F in figurex 16. This curve is the average of analyses 

of four samples of material in bottom samples collected at station A 

on June 7, 1940. The size composition of the samples is essentially 

the same as that determined on three samples of material collected 

from the large deposit*) .2 mile below the sampling section of September 

5 after the canal was drained. The results of analyses 6f the de-. 

posited sand is represented by curve O in figure 16.
BED LOAD 59

1,000,000

100,000

10,000

o 'POO

z

o

o

100

10

3.25 3.30 4.30 4.35 4.45 4.50 5.10 5.15 5.20 5.25

TIME IN MINUTES (P.M.) 

FIGUBE 20. Sediment concentrations in bottom samples from New York Canal, June 19,1940.

At the time of the observations the depth of the water in the canal 

was from 8 to 9 feet; the velocity, as measured 0.2 foot above the 

bottom, varied from 3% to 5 feet per second; and the discharge in 

the canal ranged from about 2,000 to 2,700 second-feet.

The quantity of material transported in the form of dunes could 

not be determined directly, but it is known that large quantities were 

deposited in the wide section in the canal 0.2 mile below the gage. 

Results of cross sectioning of the large deposit after the canal was

758529 48 5
60 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

drained in September 1940 show that approximately 5,200 cubic 

yards were deposited at this point. An additional 1,000 cubic yards 

is estimated to have been deposited in the big bend one mile below 

the gage. The results of weight-volume determinations of 3 samples 

of the material from the big deposit near the gage indicate that the 

average weight of the material is about 94 pounds per cubic foot. 

Using this value it is found that the 6,200 cubic yards of deposited 

material weighed approximately 7,900 tons.

The amount of sand carried along the bottom of the canal during 

1940 beyond the two points mentioned above is not known, but it is 

estimated to have been not more than 5,000 tons. Assuming this to 

be a maximum amount, the total load of bed material transported in 

the canal during the spring runoff period of 1940 appears to have 

been about 13,000 tons. The quantity of sediment measured at the 

gaging station from point samples during the 6 months ended June 

30, 1940, was approximately 83,000 tons. It is entirely possible 

that this figure includes a small portion of the load represented by 

the figure given for bed load. Assuming, however, that each figure 

represents material not included in the other, the total load transported during the 6 months was about 96,000 tons. On the basis 

of these figures the load measured at the gaging station was between 

85 and 90 percent of the total load for the period.

Examination of the canal on September 8, 1940, for a distance of 

about 24 miles below Diversion Dam showed that there were several 

small deposits at irregular intervals, usually on the inside of curves. 

Lined sections of the canal were almost completely free from deposits 

and in unlined sections for distances of 2 to 5 miles there were practically no deposits. At two points about 18K and 24 miles below 

Diversion Dam there were fairly large deposits about 200 to 300 feet 

long. (See pi. 9 A and B.} It is understood that most of the deposits in the canal except the two a short distance below the gage 

are not the result of deposition in 1940 alone but represent 

accumulations of several years.

It has been estimated that approximately 61,000 cubic yards of 

sand were removed from the canal by draglines and other mechanical 

means between 1926 and 1940.

Sand removed from the New York Canal 1

Year

1926 

1927

1928 

1929

1930.._. ...........

1931

Estimated 

volume 

(cubic yards)

9,000

6,000

4, 500

3,000

Year

1932

1933____ .....

1934 .

1935

1936

1937. 

Estimated 

volume 

(cubic yards)

7,000

3,000

15, 000

N"onc

Year

1938__. _ 

1939____ _----

TotaL 

Estimated 

volume 

(eubic yards)

7,000

None

6,500

61,000

1 Records furnished by the manager, Board of Control, Boise Project.
BED LOAD 61

BED LOAD IN STREAMS IN OTHER PARTS OF THE BOISE RIVER

DRAINAGE BASIN

The station on the New York Canal is the only one at which 

detailed observations of the movement of sand along the bottom of 

the stream bed were made. The smooth concrete bottom, ordinarily 

free of sand except at times when dunes were moving, made it the only 

station at which such measurements were practicable.

The movement of sand in streaks at irregular intervals was observed 

at other stations particularly at those with overfall sections. It is 

known that samples collected in the overfall sections sometimes 

contained more and sometimes less than the average amount of sediment being transported by the stream. However, since these samples 

were collected by lowering and raising the sample bottle from two to 

five times through the nappe and horizontally across the weir, and 

since at least two samples were collected in the section at each sampling 

period, in general the samples collected probably represent the total 

sediment concentrations in the streams during each sampling period. 

It seems unlikely that there was much, if any, movement of sand past 

the stations in the form of dunes as observed in the New York Canal.

It is fairly certain that there were no sand dunes moving past the 

station on Moore Creek above Thorn Creek, since the bottom at the 

sampling section is made of precast concrete blocks, and the presence 

of dunes would undoubtedly have been observed while bottom samples 

were being collected with the Tait-Binckley sampler. Furthermore, 

practically all of the bottom samples at that station consisted of very 

fine material which was carried in suspension.

It is possible that there was sand movement in dunes past the river 

stations on the Boise River near Twin Springs and the Boise River at 

Notus, although no direct observations could be made at those 

stations because of the high velocities and the roughness of the stream 

bottom. Bottom samples occasionally contained relatively large 

amounts of sand but not in concentrations as large as found in the 

New York Canal during the passage of the dunes. Whether in the 

form of dunes or not, the concentration of sand in bottom samples 

collected at the two stations showed that some sand was moved along 

the stream bottoms at irregular intervals during periods of high flow.

Relatively little sand was found in bottom samples collected from 

the Boise River at Dowling ranch either in 1939 or 1940. The only 

sources of the coarse material found in samples collected at the 

Dowling ranch station are a few minor tributaries and two or three 

small gold placers, which are operated irregularly during the spring 

of the year, and such sediment as may be discharged through the 

sluice gates of Arrow Rock Dam when the water level in the reservoir
62 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

falls below the second set of outlet gates. Sediment concentrations 

of bottom samples seldom exceeded 200 parts per million and usually 

ranged between 50 and 75 parts per million. Nevertheless, these 

bottom concentrations were considerably greater than those at other 

points in the vertical, which usually did not greatly exceed 25 to 30 

parts per million.

DEPOSITED SEDIMENTS 

WEIGHT-VOLUME RELATION OP DEPOSITED SEDIMENTS

The dry weight per unit volume of 71 samples of deposited sediments, collected from several points in the Boise Hiver drainage 

basin during 1939 and 1940, ranged from 51 to 121 pounds per cubic 

foot and averaged about 90 pounds. This figure of 90 pounds per 

cubic foot probably represents the average weight-volume relation of 

deposited sediments in the drainage basin. The sources and weightvolume relations of the 71 samples are given in the following table.

Dry weight per cubic foot of deposited material

Sample

No.

1 

2

3

4

5

6

7 

8

9

10

11

12

13

14

15

16

18 

19

20 

21 

22 

oq

24 

25

26 

27

28

29 

30

Date of 

collection

1939 

Mar. 30

 do 

...do ..

...do 

...do -.

... do... ..

... do__ 

...do 

... do... -

...do 

...do ..

 do 

...do .

 do 

...do ..

...doApr. 8 

. .do 

___do . 

 do 

Apr. 12 

._ .doApr. 14 

 do .

Apr. 16 

...do _

...do _ May 10 

...doLocation

Boise River, 150-200 feet below Diversion Dam near Barber. 

 .do-- 

 .do-. 

... . .do.... - 

. do. -

. do---- 

Boise River about 1 mile below Diversion Dam. 

 do.--.- .... .

 -do_- -- 

 do.- - 

Boise River about 200 feet below

Idaho Power Co. Dam at Barber. 

. do-- 

Idaho Power Co. Dam at Barber. 

 .do-. 

 do-- 

do ------

Bannock Creek near Idaho City -

do . ---.

Moore Creek above Granite Creek 

near Idaho City. 

Right bank of New York Canal about 

1 mile below gage. 

Grouse Creek near Arrow Rock . .

__._.do __ ._- 

Cottonwood Gulch at Boise about 10 

feet below weir. 

 .do ----- - 

Boise River at Notus about 200 feet 

above highway bridge.

.. do ...- .- ...... . ----.

Boise River opposite gage on New 

York Canal near Barber. 

 do..- 

Weight 

per cubic 

foot 

(pounds)

90

88

 97

89

96

86

85 

91

89

80

94

94

95

93

85

92

103 

93

84 

95 

86 

96

102 

101

86

82

81

106 

113

Remarks

From bed of stream uncovered by 

closing of Diversion Dam. 

Do.

Do.

Do.

Sand bank about 6 feet above stream

bed. 

Same as 1-4.

From bed of stream uncovered by 

closing of Diversion Dam. 

Do.

Do.

Do.

Do.

Do.

Do.

Do.

Do.

Do.

From submerged bar above weir. 

Do.

From small submerged bar near gage.

From pile cf sand dredged from canal 

over a period of years. 

From small bar about 75 feet above 

gage. 

From bar about 75 feet below gage.

From bar on left bank. 

Do.

Do. 

Do.

From bar on right bank.

From bar near left bank. 

Do.
DEPOSITED SEDIMENTS 63

Dry weight per cubic foot of deposited material Continued

Sample

No.

31 

32

33

34 

35

36 

37

38 

39

40

41

42 

43

44

45 

46

47 

48

49

50

51

B2 

53

54

55

56

57

58

59

60

61

62

63

64

65

66 

67

68

60

70

71

72

Date of 

collection

19S9 

May 14

 do 

--do.....

 do..... 

...do _.

May 19 

.__ doJune 22 

 do.....

Sept. 4

.-doSept. 10 

_-do .

 doSept. 23 

 do 

 do. 

 do....

...do....

 do.._.

... do....

Oct. 8 

 do..-_

Oct. 25

 do-._-

 do-_-

 do-..

...do....

1940 

Mar. 29

 do....

July 27

 do_.-_

 do-..

 do....

 do....

Sept. 8 

-do---

..do____

-do.-..

-do....

-do.... 

Sept. 22

Location

Moore Creek about % mile above 

Idaho City. 

 .do 

 -do .._

Elk Creek near Idaho City about 75 

feet above gage. 

--do -_.- - .- 

Cottonwood Creek near Arrow Rock 

about 15 feet below weir, 

--.do ------ 

Bannock Creek near Idaho City 

__ do__ - _ _____ .

Elk Creek near Idaho City ... ____ ...

--.do 

Boise River about 2.4 miles below gage 

near Twin Springs.

 do ..._ ....

Creek, about 7.1 miles below gage 

near Twin Springs. 

Boise River about 7.2 miles above Diversion Dam near Barber, 

--.-do 

Moore Creek about 1.0 mile above 

bridge at mouth.

bridge at mouth.

bridge at mouth.

bridge at mouth.

bridge at mouth and 300 feet below 

Grimes Creek. 

Arrow Rock Reservoir, l/i mile above 

dam. 

 do.. . 

 .do...... . .... ....... .....

 -do.-_ ... . 

 .do.. . .

 do.. .... ...... .

..... do.. ... ... ...... ....

do . -----

.... do.. . 

New York Canal 0.2 mile below gage.. 

 .do..... ... ... ... ... ... -

 do. _ 

Diversion Dam.

York Canal 18.4 miles below Diversion Dam. 

New York Canal 18.6 miles below 

Diversion Dam.

Weight 

per cubic 

foot 

(pounds)

95 

ini

71

86

QQ

84

104

93

88

105

102

51

Q9

CO

102

99 

98

97

96

91

77 

53

94

100

105

72

121

100

96

. 93

107

86

92

92 

94

95

82

82

87

Remarks

From sand flat about 300 feet wide. 

Do.

Do.

From sandy bed of stream. 

Do.

From submerged bar. 

Do.

From submerged bar above weir. 

Do.

From sandy bottom at bridge above

gage. 

Do.

From bar uncovered by lowering of 

water in Arrow Rock reservoir. 

Fine sand containing organic 

matter.

42.

water in Arrow Rock reservoir and 

uncovered by lowering of water. 

From bar on right bank.

Do.

From one of several bars between 

boulders.

torn of auxiliary channel at higher 

stages. 

About 15 feet above reservoir backwater.

water. 

From large sand deposit.

Do.

Do.

Do.

Do. 

Do.

edge of reservoir backwater.

backwater. 

Debris cone 400 feet above backwater. 

Debris cone 400 feet below gage

house.

house. 

From downstream edge of large sand 

deposit. 

From center of large sand deposit.

deposit.

curve.

gates.

From center of large sand deposit 

about 300 feet long.

bridge.
64 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

SIZE COMPOSITION OF DEPOSITED SEDIMENTS

Size analyses were made on the 71 samples of deposited sediments 

collected for the determination of weight-volume relation and on four 

samples of bottom material from dunes in the New York Canal. 

Results of these analyses are given on pages 140 to 143.

Graphs of a large number of the analyses are shown in figure 21. 

Curve A represents the average particle-size distribution in three 

samples of deposited material from the Boise River at Notus; curve 

B represents the analysis of a single sample from Cotton wood Creek 

at Arrow Rock Reservoir; curve C is the average of 14 analyses of 

samples of river-bed sediments collected from the Boise River between 

Diversion Dam and the Idaho Power Co. Dam about 2 miles downstream; curve D is the average of 4 samples from Cotton wood Gulch; 

curve E is the average of 6 samples from Moore Creek between Grimes 

Creek and the Boise River; curve F is the average of 4 samples from 

Elk Creek; and curve G is the average of 3 samples from the New 

York Canal. Curves B to G, inclusive, show that deposited sediments in the streams above Boise are composed of predominately 

coarse material in which from about 40 to 70 percent of the material 

is larger than 1.00 millimeter. The sediment in the samples from 

Notus was somewhat finer, as would be expected since Notus is near 

the lower end of the Boise River Valley.

SPECIFIC GRAVITY OF SAMPLES OF DEPOSITED SEDIMENTS

Determinations of specific gravity were made on 77 samples of 

deposited material collected from different parts of the Boise River 

drainage basin. They were made on portions of 58 samples collected 

for determination of weight-volume relations arid on 19 additional 

samples collected for size analysis. The term "specific gravity" 

refers to the weight of the sediment particles, not including pore 

space, compared to the weight of an equal volume of water as unity.

The specific-gravity determinations were made in Le Chatelier 

flasks lising kerosene as the liquid medium. The minimum specific 

gravity determined was 2.20 on a sample from a mud deposit in Arrow 

Rock Reservoir at the mouth of Cottonwood Creek, which was uncovered when water was released from the reservoir. The maximum 

specific gravity was 2.67, determined on a sample from the bed of Elk 

Creek near Idaho City. The specific gravities of all but 7 of the 77 

samples were greater than 2.50. The average specific gravity computed from the results of these 70 samples is 2.59. If the 7 samples 

having a specific gravity of less than 2.50 are included, the average 

is 2.57.

The seven samples for which the specific gravity was less than 2.50 

were collected from areas where fine material was deposited in back-
DEPOSITED SEDIMENTS 65

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66 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

water behind Arrow Rock Dam or in quiet pools or eddies along stream 

banks. The average specific gravity of 2.59 for the 70 samples collected over the area is only slightly less than 2.65, which is the figure 

usually given for clean quartz sand.

SOURCE OF SEDIMENT DEPOSITED ABOVE DIVERSION DAM

The source of the coarse sediment deposited in the pool above 

Diversion Dam was not definitely established because of the absence 

of sediment-measuring stations on Grimes Creek and on Moore Creek 

near the mouth, and also because of the short period of the investigation.

Relatively large quantities of sediment are deposited in Arrow 

Rock Reservoir as shown in plates 10 and 11. However, the quantity 

of material carried by water released from Arrow Rock Reservoir is 

relatively very small except for short periods in some years when 

sediment is sluiced from the reservoir. During years of small runoff 

Arrow Rock Reservoir is usually drained by opening the sluice gates, 

thus permitting the natural flow in the Boise River to pass through 

the dam unobstructed. During the years 1938, 1939, and 1940 there 

was sufficient storage to supply the irrigation needs of the Boise 

project and, consequently, it was not possible to obtain samples of 

the sediment that is carried through the dam when the sluice gates 

are open. However, in the Boise River large quantities of sediment 

are known to move downstream from Arrow Rock Reservoir during 

sluicing, part of which may have been deposited above Diversion 

Dam. The river channel between Arrow Rock Dam and Moore 

Creek wa§ free of deposited sediment during the 18 months of the 

investigation, which shows that the sediment sluiced from the reservoir 

prior to 1938 was entirely removed from this section of the river 

channel.

Sediment deposited in the channel of Moore Creek below Grimes 

Creek was very coarse. Size analyses of six samples, collected from 

the stream channel between Grimes Creek and the Boise River at a 

time when the discharge was low, show that from 70 to 80 percent in 

most of the samples consisted of particles greater than 1.00 millimeter 

in diameter. Four of these analyses are shown in figure 22.

Results of size analyses of five samples collected from the sediment 

deposited in the pool above Diversion Dam (see pi. 12, A and B] at 

a time when the dam was open and the entire flow of the Boise River 

passed through the dam unobstructed, are plotted^in figure 23. The 

analyses show that from 60 to 70 percent of the material in all but one 

sample consisted of particles greater than 1.00 millimeter in diameter. 

The size composition was similar to that of samples of bed-load 

material in the New York Canal.

The available data seem to indicate that the greater part of the 

sediment deposited in the Boise River above Diversion Dam originated
DEPOSITED SEDIMENTS 67

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89 aoavnosia QKV ' asioa H3AIH Kisva 
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1048 PLATE 9

A. COARSE SEDIMENT DEPOSITED IN NEW YORK CANAL, 18.6 MILES BELOW DIVERSION

DAM x

B. FINE SEDIMENT DEPOSITED IN FARM LATERAL DITCH OPPOSITE GATE IN NEW YORK 

CANAL, 18.4 MILES BELOW DIVERSION DAM.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1048 PLATE 10

A. ARROW ROCK RESERVOIR AT MOUTH OF COTTONWOOD CREEK.

Reservoir is under complete drawdown at this point. Natural flow in Boise River cutting through alluvia 

fan built up by material brought in by Cottonwood Creek.

B. ALTERNATE LAYERS OF FINE MUD AND COARSE SAND DEPOSITED AT MOUTH OF

COTTONWOOD CREEK.

The four light-colored bands represent coarse material deposited by Cottonwood Creek presumably during

4 successive years.
SLUICING OF ARROW ROCK RESERVOIR

in the Moore Creek drainage basin, although some of it may have come 

from sediment sluiced from Arrow Rock Reservoir prior to 1938, 

Probably little if any of the coarse material from Moore Creek originated upstream from the station above Thorn Creek during the period 

of the investigation. It is probable that some coarse sediment was 

carried downstream from the placered area in Moore Creek near 

Idaho City during earlier years. Fragmentary data indicate that 

large quantities of sediment were carried into Moore Creek below 

Thorn Creek from Grimes Creek, and that a considerable proportion 

of the sediment from this source consisted of coarse material.

SLUICING OF ARROW ROCK RESERVOIR

The regulation of flow and storage in Arrow Rock Reservoir began 

in February 1915. Water may be discharged through the dam at 

three elevations. The first set of 10 outlets is at elevation 3,105 

feet, a second set of 10 outlets is at elevation 3,018 feet, and 5 sluice 

gates are at elevation 2,967 feet. Elevations refer to the center line 

of openings. In releasing water from the reservoir it is customary to 

utilize outlets in 1 of the 2 upper sets until the reservoir is drawn 

down to within about 20 or 30 feet of the second row of outlet openings. Because of the variations in discharge resulting from changing 

head as the water surface approaches the second set of outlets, it is 

then the usual custom to discharge in whole or in part through the 

openings in the sluice gates.

The sluicing effect produced by discharging water through the 

sluice gates is reported to be greater when the impounded storage is 

practically exhausted and the natural flow of the river is allowed to 

pass through with all sluice gates open. The manager of the Boise 

Project Board of Control has furnished a list of the periods, since the 

reservoir was constructed, when this condition prevailed. The dates 

and length of period in days in each year during which the sluice 

gates were open, together with the average discharge for each period, 

are given in the following table.

Record of sluicing from Arrow Rock Reservoir

Year

1919

1920

1922

1924

1926

1928

1,929

1931

1933

1934

1935

1937

Period of sluicing

Sept. 13-17, Sept. 20-Oct. l.._ .. .......... 

Sept. 13-Oct. 10-.---. _ ................... _ --.--..-.--. __ .......

Sept. 19-Oct. 22-. .............. .............. .... ...... .-. 

Aug. 19-Oct. 15.............................. _ . _ -- -- _ ------- -

Sept. 16-Oct. 16 ... 

Oct. 8-21 . ................... ........ ................. ......

Oct. 20-31 _ __..._.__.__.._ _.. ___.. _ 

Oct. 13-Nov. 7 -...- ---. --..__-- - - 

Oct. 16-30. - - _. . -. - - ---

Oct. 14-24 .. .......................................................

Oct. 22-26 _ - - 

Oct. 10-25 ............................................ .............

Number 

of days

17

28

34

58

31

14

12

26

15

11

4

16

Average 

discharge 

(second-feet)

576

721

701

439

518

704

608

548

597

569

566

607
70 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

There is no information concerning the quantity of sediment that 

was removed from the reservoir during the sluicing periods. The 

reservoir was not drained down to a point for effective sluicing during 

the years 1938, 1939, and 1940. The sediment loads measured at the 

station at Dowling Ranch furnish no basis for computing the quantities 

of sediment removed from the reservoir during the sluicing periods.

Inasmuch as the sluice gates are utilized in making water deliveries 

when the reservoir level approaches the elevation of the second row 

of outlets, periods of sluicing given in the preceding table may not 

include all the periods when some sluicing effect may have been experienced. The capacity table used for Arrow Rock Reservoir is 

based on inflow and outflow studies, and in irrigation operations it 

is adjusted from time to time for the estimated accumulations of sediment. Data showing the areas submerged and the capacities of the 

reservoir at several water-surface elevations were obtained from 

original records of the contour survey.

Submerged areas and storage in Arrow Rock Reservoir corresponding to several

water-surface elevations

Elevation

3,048

3,038

3,018

2,967

2,956

Gate reference

Area 

submerged 

(acres)

362

290

178

22

0

Storage (acrefeet)

12, 968

9,676

5,032

132

0

Periods during years when the reservoir level was below elevation 

3,018 feet, and when discharges were effected only through the sluice 

gates, are given in the following table. These data include the periods

Periods when water level in Arrow Rock Reservoir was below elevation 3,018 feet

Year

1915

1917

1919

1920

1922

1924

1826

1927

1928

1929

1930

1931

]932

1P33

1934

1935

1936

1937

Period

Feb. 24-28, Oct. 21-31.... ........... . .. .............. ............

Sept. 2-Oct.6____. .____. ......... _-_.---.--.. _--- -.-- 

Sept. 6-Oct. 13.......................................................

Sept. 16-Oct. 26.... ........ ............. .............................

July 25-Oct. 31......................... ...........................

Oct. 21-24-... ......... .... .. . .. .... ...........

Sept. 28-Oct. 2S-... .................................................

Oct. 6-11- ..---....... ......... .. ... ... . . ............

Aug. 13-Nov. 14. ........................ ...........................

Oct. 21-28 ......... . . . ...........

Oct. 14-Nov. 1........... .................................... ........

Oct. 11-30.... ...... .r . .................. ............................

Oct. 18-Nov. 9- ............................................ .......

Oct. 12^-19.. ............ .......................................... .

Oct. 7-Nov. 2... .....................................................

Number 

of 

days

16

24

35

38

42

99

53

4

28

38

6

94

8

19

20

23

8

27

Average 

discharge 

(second-feet)

574

750

615

723

720

463

536

790

696

579

1,090

440

728

654

613

637

700

590
VARIATIONS IN CHANNEL CROSS SECTIONS 71

previously tabulated and other periods when some sluicing effect may 

have been experienced. The average discharge for each of these 

longer periods is also shown. The mean discharges during these 

longer periods vary from the average to a greater degree than in the 

preceding tabulation for the reason that both filling and emptying 

processes are included.

VARIATIONS IN CHANNEL CROSS SECTIONS IN THE 

VICINITY OF GAGING STATIONS

Several channel cross sections were obtained at and near all but one 

of the gaging stations included in this investigation. Inasmuch as the 

channel of the New York Canal is lined with concrete above and below 

that gaging station none was obtained there. Measurements were 

made at three different periods at most of the stations. The first 

period was early in 1939 before the spring runoff, the second in the 

summer of 1939 after the spring runoff, and the third in the summer of 

1940 after the spring runoff.

The sections selected at each station were tied in to markers on the 

banks of the stream. Transverse profiles of the channel bottom 

between each pair of markers were developed by leveling. The 

station gage datum was used as the elevation reference.

The cross-section notes for each section selected at or near the 

gaging stations were reduced. Parallel plottings were made for each, 

showing the transverse profiles of the stream bed between the markers 

for the dates on which the surveys were made. These plottings are on 

file in the Geological Survey district office in Boise. Mean stream bed 

elevations were computed from the plottings for each cross section at 

each of the stations for the several surveys.

The changes in elevation of the channel beds at and near the gaging 

stations do not appear consequential except at the initial location of 

the station on Elk Creek near Idaho City. Within a channel reach of 

102 feet adjacent to this station the channel bed aggraded an average 

of 1.51 feet between March 24 and June 22, 1939; 0.1 foot, June 22 to 

July 15, 1939; and 0.78 foot, July 15 to October 25, 1939. With this 

exception the stream channels at and near the gaging stations remained 

relatively stable during the period of the investigation.

The relative stability of the channel beds at the gaging stations does 

not mean that there was no degradation or aggradation of the beds in 

other reaches of the streams. Certain sections may have gradients 

sufficiently flat that deposition of sediment may be appreciable. 

Other sections may have gradients so steep that erosion may take 

place. Furthermore, a reach of stream bed may degrade during a 

period of a few weeks, months, or years and then aggrade during:
72 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

another period. Changes in channel beds at and near the gaging 

stations may be caused by artificial means such as construction of 

gage housings, sediment sampling structures, artificial controls, and 

riprap bank protection. They may also be caused by other artificial 

operations such as various forms of placer mining which affect the 

natural regimen of the streams. Still other operations that may affect 

directly or indirectly the stability of channel bed are those connected 

with grazing, timber-cutting practices, road building, and the ravages 

of fire. There appears to be no direct evidence, however, of any 

significant changes in stream beds in the vicinity of any of the gaging 

stations during the period of the investigation except at the station on 

Elk Creek near Idaho City, where placer sediments filled the channel 

to an average depth of about 2.5 feet.

Variations of mean elevation of stream beds in vicinity of gaging stations 

Boise River near Twin Springs

fross-section location 

with respect to gage

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Mar. 8, 

1939

1.20 

1.10 

1.11 

.97 

1.88

1.31

Aug. 14, 

1939

1.16 

1.34

.90 

1.82

11.34

Sept. 26, 

1940

1.25 

1.40 

1.22 

1.00 

1.84

1.34

Remarks

Boise River at Dowling ranch near Arrow Rock

Cross-section location 

with respect to gage

A t fratrf

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Mar. 22, 1939

1.38 

.76 

1.21

1.12

Oct. 28, 1940

1.38

.77 

1.17

1.11

Remarks

Since 1915 Arrow Rock Reservoir has 

been operated for storage of river 

flow above station. No sluicing 

operation during period of investigation.

Boise River at Notus

Cross-section location 

with respect to gage

1,090 feet downstream.. .....

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Mar. 10, 

1939

2.81 

1.87 

.64

1.77

July Ifl, 

1939

2.72 

2.07 

.60

1.80

June 24, 

1940

2.91 

2.17

.72

1.93

Remarks

Considerable channel work has been 

done in river bed between Boise and 

Notus during the past several years.

»Weighted.
VARIATIONS IN CHANNEL CROSS SECTIONS 73

Variations of mean elevation of stream beds in vicinity of gaging stations Continued

Cottonwood Creek at Arrow Rock Reservoir

Cross-section location with 

respect to gage

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Mar. 25, 

1939

1.58 

2.01 

2.21 

3.37

2.29

July 13, 

1939

1.84 

2.04 

2.32 

3.23

2.36

June 20, 

1940

2.10 

2.38 

2.40 

3.35

2.56

Remarks

Grouse Creek near Arrow Rock

Cross-section location with 

respect to gage

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Mar. 11, 

1939

2.90 

3.43 

4.09 

5.30 

6.62 

8.48 

11.02

5.98

Aug. 4, 

1939

2.91 

3.33 

3.87 

5.21 

6.76 

8.43 

10.62

5.88

JUT1P21,

1940

3.13 

3.65 

4.12 

5.48 

6.87 

8.24 

10.48

e.oo

Remarks

Several check dams were constructed 

on creek and tributaries farther 

upstream during fall of 1939.

Moore Creek above Granite Creek near Idaho City

Cross-section location with 

respect to gage

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Mar. 23, 

1939

0.80 

1.13

.96

July 15, 

1939

0.83 

1.04

.94

June 13, 

1940

1.18 

1.54

1.36

Remarks

A diversion from Moore Creek 4ji 

miles upstream from station furnishes 

water for use in placering operations 

at Gold Hill.

Moore Creek above Thorn Creek near Idaho City

Cross-section location with 

respect to gage

93 feet upstream _ ... ....

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Mar. 18, 

1939

1.72 

1.49 

2.80 

3.62

2.41

July 13, 

1939

1.80 

1.72 

2.80 

3.58

2.48

July 5, 

1940

1.70 

1.74 

2.92 

3.61

2.49

Remarks

Placer mining including dredging was 

carried on above station throughout 

the investigation. A section of highway was constructed through the 

dredged area during the winter of 

1939-40.
74 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

Variations of mean elevation of stream beds in vicinity of gaging stations Continued

Granite Creek near Idaho City

Cross-section location with 

respect to gage

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Apr. 7, 

1939

2.20 

3.03 

5.54 

10.64

5.35

July 14, 

1939

2.09 

2.88 

5.08 

10.74

5.20

June 7, 

1940

2.41 

3.01 

5.23 

10.61

5.32

Remarks

Bannock Creek near Idaho City

Cross-section location with 

respect to gage

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Apr. 8, 

1939

0.33 

1.56 

2.54 

3.87 

3.91

2.44

July 12, 

1939

0.45 

1.51 

2.40 

3.73 

3.90

2.40

June 7, 

1940

0.67 

1.41 

2.33 

3.55 

3.75

2.34

Remarks

Approximately 12.5 cubic yards of sand 

removedfrom weir pool during period 

of investigation.

Pine Creek near Idaho City

Cross-section location 

with respect to gage

Mean elevation of stream bed in feet, 

referred to gage datum, on dates 

indicated

Apr. 7, 1939

2.21

3.53 

4. 28 

5.64

3.92

July 14, 1939

2.26

3.60 

4.26 

5.49

3. HO

Remarks

Station operated at this location Jan. 

16, 1939, to Feb. 1'2, 1910. Because 

of the construction of Barry Placer 

diversion ditch the station was 

moved % mile upstream.

Pine Creek above Barry placer diversion near Idaho City

Cross-section location 

with respect to gage

Mean elevation of 

referred to gage 

indicated

Mar. 13, 1940

4 40

4.87

5.79

7.20

8.84

12.75

7.31

stream bed in feet, 

datum, on dates

June 8, 1940

4.31

5.05

5.77

7.28

S.94

12.50

7.31

Remarks

A diversion 1J6 miles above station

furnishes water for Davis Placer 

outside of drainage basin.
GEOLOGICAL StJEVEY WATEE-SUPPLY PAPEE 1048 PLATE 11

A, DEBRIS CONE AT MOUTH OF SIDE CANYON ENTERING GROUSE CREEK, 1 MILE ABOVE

GAGING STATION.

B. SEDIMENT AND DEBRIS DEPOSITED AT MOUT11 OF GROUSE CREEK EXPOSED BY 

DRAWDOWN IN ARROW ROCK RESERVOIR.

Deposits extend about a mile upstream to a point corresponding with the maximum level of water in the

reservoir.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1048 PLATE 12

A. VIEW UPSTREAM SHOWING SEDIMEMT DEPOSITED BEHIND DAM. CHANNEL IN 

FOREG11OLND IS ABOU'l 12 FEET BELOW TOP OF DEPOSIT.

B. VIEW DOWNSTREAM SHOWING DAM AT RIGHT AND HEAD GATES AT INTAKE OF 

NEW YORK CANAL AT LEFT OF POWERHOUSE.

BOISE RIVER AT DIVERSION DAM.
VARIATIONS IN CHANNEL CROSS SECTIONS 75

Variations of mean elevation of stream beds in vicinity of gaging stations Continued

Elk Creek near Idaho City

Cross-section location 

with respect to gage

Mean elevation of stream bed in feet, 

referred to gage datum, on dates 

indicated

Mar. 24, 

1939

1.91

1.80 

1.85 

2.24

1.95

June 22, 

1939

3.05

3.28 

3.58 

3.95

3.46

Julv 15, 

1939

3.17

3.51 

3.87 

4.04

3.65

Oct. 25, 

1939

4.04

4.07 

4.64 

4.97

4.43

Remarks

Operated at this location Jan. 20, 

1939 to Feb. 4, 1940. Because of 

resumption of operations at Gold 

Hill and Rubow Placers, station 

was moved 4^6 miles upstream.

Elk Creek above Gold Hill placer diversion near Idaho City

Cross-section location 

with respect to gage

Mean elevation 

feet, referred to 

dates indicated

Mar. 22, 1940

0.22

.92

3.34

5.29

5.59

3.07

}f stream bed in 

gage datum, on

June 19, 1940

0.52

.99

2.hO

4.66

5.61

2.92

Remarks

June 30, 1940, above diversions for 

Gold Hill and Rubow Placers.

Cottonwood Gulch at Boise

Cross-section location 

with respect to gage

Mean elevation of stream bed in 

feet, referred to gage datum, on 

dates indicated

Mar. 13, 

1939

3.62 

3.77 

3.82 

7.00 

8.45

5.33

Aug. 3, 

1939

3.52 

3.63 

3.84 

6.65 

8.25

5.18

June 22, 

1940

3.64 

3.57 

3.83 

6.55

7.88

5.09

Remarks

Old debris dam 550 feet above station.

Weighted.

758529 48-
76 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

DAILY DISCHARGE AND SEDIMENT LOADS

The mean daily discharge in second-feet and daily sediment loads 

in tons measured at each of the 13 stations during the 18-month period 

ended June 30, 1940, are given in the following table. Discharge data 

for all important diversions in the Idaho City area are included. For 

some of the stations sediment loads reported represent total sediment 

loads and for other stations they represent only the suspended sediment loads. The type of load measured is indicated for each station. 

For those stations without overfall sections the probable relation of the 

measured suspended loads to the total loads is given in the table on 

page 30.

STATION DESCRIPTIONS

The following descriptions apply to the stations for which records 

on sediment loads and size analyses of sediments are given in the tables 

on pages 82 to 139.

Boise River near Twin Springs, Idaho

LOCATION. Water-stage recorder, lat. 43°40', long. 115°44', in NW% sec. 27,

T. 4 N., R. 6 E., % mile upstream from Birch Creek, 4 miles downstream from

Twin Springs and 13 miles upstream from Arrow Rock. 

DRAINAGE AREA. 830 square miles.

DISCHARGE RECORDS. Station established March 21, 1911. 

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 17, 1939,

to June 30, 1940. 

EXTREMES. Sediment load: Maximum, 5,450 tons May 12, 1940; minimum, 1.2

tons September 1 1, 1939. 

Sediment concentration: Maximum observed, 590 parts per million March 27,

1940. 

DiVErtsiONS. No important diversion or regulation. Minor diversions for

placering and irrigation within the basin from tributaries above station.

Boise River at Notus, Idaho

LOCATION. Water-stage recorder, lat. 43°43', Ion-?. 116°48', in SE^SE^, sec.

34, T. 5 N., R. 4 W., 360 yards upstream from steel highway bridge, % mile

southeast of Notus and 7 miles northwest of Caldwell. 

DRAINAGE AREA. 3,820 square miles. 

DISCHARGE RECORDS. Station established April 1, 1920. 

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 13, 1939,

to June 30, 1940. 

EXTREMES. Sediment load: Maximum, 8,600 tons April 2, 1939; minimum 0.3

ton August 3, 1939. 

Sediment concentration: Maximum observed, 1,610 parts per million March 28,

1940. 

DIVERSIONS. Station is below all diversions for irrigation in Boise Valley. Flow

regulated by storage in Arrow Rock Reservoir. Several irrigation diversions

above station including the New York Canal. Records for New York Canal

are given in this report.
DAILY DISCHARGE AND SEDIMENT LOADS 77 

Boise River at Dowling ranch near Arrow Rock, Idaho

LOCATION. Water-stage recorder, lat. 43°35', long. 115°58', in SE^SW^ sec.

15, T 3 N., R. 4 E., at Dowling ranch, % mile upstream from Moore Creek

and 4 miles downstream from Arrow Rock. 

DRAINAGE AREA. 2,220 square miles.

DICSHARGE RECORDS. Station established March 12, 1911. 

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 17, 1939, to

June 30, 1940. 

EXTREMES. Sediment load: Maximum, 1,270 tons May 14, 1940; minimum, 0.01

ton Nov. 5, 1939, and Jan. 8, 1940. 

Sediment concentration: Maximum observed, 235 parts per million Mar. 1,

1940. 

DIVERSIONS. No important diversions from river above station. Flow regulated

by Arrow Rock Reservoir on river and by Little Camas Reservoir on Little

Camas Greek. Minor diversions for placering and irrigation within the

basin from tributaries.

Cotton wood Creek near Arrow Rock Reservoir, Idaho

LOCATION. Water stage recorder and broad-crested wooden control structure 

with overfall, with trapezoidal notch for low stages, lat. 43°38', long. 115°49', 

in NWJ4NEJ4 sec. 2, T. 3 N., R. 5 E., at flow line of Arrow Rock Reservoir, 

% mile downstream from Ranger Creek and Cottonwood ranger station arid 

5% miles northeast of Arrow Rock.

DRAINAGE AREA. 21.4 square miles.

DISCHARGE RECORDS. Station established January 23, 1939 (at site 0.4 mile upstream, March 7, 1914, to September 30, 1918).

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 23, 1939, 

to June 30, 1940.

EXTREMES. Sediment load: Maximum, 1,080 tons March 28, 1940; minimum,

0.001 ton September 10, 1940.

Sediment concentration: Maximum observed, 18,700 parts per million March 

28, 1940.

DIVERSIONS. One small diversion for irrigation within the basin.

Grouse Creek near Arrow Rock, Idaho

LOCATION. Water-stage recorder and broad-crested wooden control structure 

with overfall, with rectangular flume for low stages, lat. 43°35', long. 115°55', 

in SWX sec. 19, T. 3 N., R. 5 E., at Sanders ranch, at flow line of Arrow Rock 

Reservoir, 1J4 miles southeast of Arrow Rock.

DRAINAGE AREA. 8.0 square miles.

DISCHARGE RECORDS. Station established January 20, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 20, 1939, to 

June 30, 1940.

EXTREMES. Sediment load: Maximum, 3,950 tons March 27, 1939; minimum,

0.003 ton on several days during period of record.

Sediment concentration: Maximum observed, 93,600 parts per million March 

23, 1939.

DIVERSIONS. No important diversion or regulation above station.
78 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN 

Moore Creek above Granite Creek near Idaho City, Idaho

LOCATION. Water-stage recorder and artificial control without overfall, lat. 

43°50', long. 115°47', in SE#SE# sec. 19, T. 6 N., R. 6 E., % mile upstream 

from Granite Creek, and 2% miles northeast of Idaho City.

DRAINAGE AREA. 37.0 square miles.

DISCHARGE RECORDS. Station established January 20, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 20, 1939, 

to June 30, 1940.

EXTREMES. Sediment load: Maximum, 884 tons March 27, 1940; minimum,

0.008 ton September 10, 1939.

Sediment concentration: Maximum observed, 2,900 parts per million, March 

25, 1940.

DIVERSIONS. One important diversion. Gold Hill Placer diversion, located 

4% miles upstream from station, used principally for mining purposes at 

Gold Hill Placer. A small part is used to supplement the domestic supply 

at Idaho City. Return flow enters below gaging station. Records of daily 

discharge are given in this report.

Moore Creek above Thorn Creek near Idaho City, Idaho

LOCATION. Water-stage recorder and broad-crested control structure without 

overfall, lat. 43°46', long. 115°55', in NW^NWtf sec. 18, T. 5 N., R. 5 E., 

1% miles upstream from Thorn Creek and 5}i miles southwest of Idaho City.

DRAINAGE AREA. 119 square miles.

DISCHARGE RECORDS. Station established January 28, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 28, 1939 

to June 30, 1940.

EXTREMES. Sediment load: Maximum, 4,550 tons March 27, 1940; minimum,

5.3 tons August 22, 1939.

Sediment concentration: Maximum observed 4,390 parts per million June 

12, 1939.

DIVERSIONS. Many diversions for placering purposes within the basin above the 

station. A small ditch diverting from Thorn Creek carries water into this 

basin via Pine Creek. Flow slightly regulated by passage through dredged 

areas in vicinity of Idaho City. Records of daily discharge for diversion 

from Thorn Creek into Pine Creek near Idaho City are given in this report. 

(See under Pine Creek above Barry diversion.)

Granite Creek near Idaho City, Idaho

LOCATION. Water-stage recorder and broad-crested wooden control structure 

with overfall, with modified Parshall flume for low stages, lat. 43°49'30", 

long. 115°47'00", in NE%SE% sec. 30, T. 6 N., R. 6 E., % mile upstream from 

mouth and 2% miles east of Idaho City.

DRAINAGE AREA. 4.8 square miles.

DISCHARGE RECORDS. Station established January 16, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 18, 1931* 

to June 30, 1940.

EXTREMES. Sediment load: Maximum, 392 tons March 27, 1940; minimum,

0.001 ton on several days during period of record.

Sediment concentration: Maximum observed, 61,200 parts per million March 

1; 1940.

DIVERSIONS. No important diversion or regulation above station.
DAILY DISCHARGE AND SEDIMENT LOADS * 79 

Bannock Creek near Idaho City, Idaho

LOCATION. Water-stage recorder and broad-crested wooden weir with V-notch 

with overfall, lat. 43°48'30", long. 115°46'30", in SE^SWM sec. 32, T. 6 

N., R. 6 E., % mile upstream from South Pork, 2% miles upstream from confluence with Moore Creek, and 3% miles southeast of Idaho City.

DRAINAGE AREA. 4.5 square miles.

DISCHARGE RECORDS. Station established January 16, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 16, 1939, 

to June 30, 1940.

EXTREMES. Sediment load: Maximum, 135 tons March 27, 1940; minimum,

0.001 ton on many days during period of record.

Sediment concentration: Maximum observed, 10,900 parts per million March 

27, 1940.

DIVERSIONS. One small diversion within the basin at experimental plot above 

station.

Pine Creek near Idaho City, Idaho

LOCATION. Water-stage recorder and broad-crested wooden control structure 

with overfall, with rectangular flume for low stages, lat. 43°49'00", long. 

115°48'30", in SW#NE# sec. 36, T. 6 N, R. 5' E , % mile upstream from 

Steamboat Gulch, % mile upstream from mouth, and 1% miles southeast of 

Idaho City.

DRAINAGE AREA. 6.5 square miles.

DISCHARGE RECORDS. Station established January 16, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 16, 1939, 

to February 12, 1940. Station moved % mile upstream prior to initial operation of Barry Placer diversion. (See description below.)

EXTREMES. Sediment load: Maximum, 49 tons March 22, 1939; minimum, 0.001

ton on many days during period of record.

Sediment concentration: Maximum observed, 4,220 parts per million March 

22, 1939.

Pine Creek above Barry Placer diversion near Idaho City Idaho

LOCATION. Water-stage recorder and broad-crested wooden control structure 

with rectangular flume for low stages, lat. 43°48'30", long. 115°48'00", in 

NW%NE}4 sec. 1, T. 5 N., R. 5 E., 100 feet upstream from headgates of 

Barry Placer diversion, 1 mile upstream from Steamboat Gulch, 1}£ miles 

upstream from mouth, and 2 miles southeast of Idaho City.

DRAINAGE AREA. 6.1 square miles.

DISCHARGE RECORDS. Station established February 13, 1940.

SEDIMENT-LOAD RECORDS. Sediment loads determined from February 13, 1940, 

to June 30, 1940, from overfall structure 40 feet downstream from gage.

EXTREMES. Sediment load: Maximum, 2,840 tons March 27, 1940; minimum,

0.004 ton May 30, 1940.

Sediment concentration: Maximum observed, 85,000 parts per million March 

27,-1940.

DIVERSIONS. One diversion, Da vis Placer diversion from Pine Creek, 1% miles 

upstream from station, used for mining and domestic purposes at several 

placer claims. Return flow enters below gaging station. Pine Creek receives 

water above Da vis Placer diversion by a small ditch that diverts from Thorn 

Creek in NW% sec. 21, T. 5 N , R. 6 E. Records of discharge for these two 

diversions are given in this report.
80 - DISCHARGE AND SEDIMENT, BOISE RIVER BASIN 

Elk Creek near Idaho City, Idaho

LOCATION. Water-stage recorder, lat. 43°50'30", long. 115°49'30", in

sec. 23, T. 6 N., R 5 E., 400 feet upstream from Spanish Fork and 1 mile 

north of Idaho City.

DEAINAGE AREA. 22.3 square miles.

DISCHAEGE EECORDS. Station established January 20, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 20, 1939, 

to February 4, 1940; station moved 4% miles upstream. (See description 

below.)

EXTREMES. Sediment load: Maximum, 364 tons March 25, 1939; minimum, 0.02

ton February 8, 1939.

Sediment concentration: Maximum observed, 56,300 parts per million June 

9, 1939.

DIVERSIONS. An important diversion, Gold Hill Placer diversion, from Elk 

Creek near Idaho City, 4% miles upstream from station, is used for mining 

purposes at Gold Hill Placer. Return flow, Gold Hill Placer diversion, 

normally enters below station. During short periods in May, June, and 

July 1939, a small part of the return flow was rediverted and entered at 

Rubow Placer adjacent to Elk Creek, X mue above gaging station. In 

October and November 1939, return flow also reentered Elk Creek via 

Eldorado Gulch 1% miles upstream from station.

A second diversion, Rubow diversion No. 3 from Elk Creek near Idaho City, 

1% miles upstream from station, is used for mining purposes at Rubow 

Placer on Spanish Fork. Return flow enters below the gaging station. 

A third diversion, Rubow diversion No. 2 from Elk "Creek near Idaho City, 

IK miles upstream from station, is used in part at Rubow Placer adjacent to 

Elk Creek and in part at Rubow Placer on Spanish Fork. The return flow 

from the first part enters above the gaging station and from the second part 

below the gaging station. A record of discharge was collected below point 

where first part is used to show net diversion to placer claims outside the basin.

Elk Creek above Gold Hill Placer diversion, near Idaho City, Idaho

LOCATION. Water-stage recorder and artificial control, lat. 43°54'00", long.

115°47'30", in SWJ4NWJ4 sec. 31, T. 7 N., R. 6 E., % mile upstream from

head gates of Gold Hill Placer diversion, J4 mile above Forest King Gulch,

and 5)£ miles north of Idaho City. 

DRAINAGE AEEA. 13.1 square miles.

DISCHARGE EECORDS. Station established February 4, 1940. 

SEDIMENT-LOAD EECOEDS. Sediment loads determined from February 4, 1940, to

June 30, 1940 at overfall structure 50 feet downstream from gaga. 

EXTREMES. Sediment load: Maximum, 180 tons March 27, 1940; minimum,

0.04 ton February 5, 1940. 

Sediment concentration: Maximum observed, 1,840 parts per million March 25,

1940. 

DIVERSIONS. No diversion or regulation above station.
DAILY DISCHARGE AND SEDIMENT LOADS 81 

New York Canal near Barber, Idaho

LOCATION. Water-stage recorder and trapezoidal concrete-lined canal section, 

lat. 43°33', long. 116°07' f in SE^NEX sec. 32, T. 3 N., R. 3 E., 1% miles 

downstream from head gates at Boise River diversion dam and power plant, 

1 mile south of Barber and 6 miles southeast of Boise post office.

DISCHARGE RECORDS. Station established February 1, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from February 1, 1939, 

to June 30, 1940. (Records collected by Boise River watermaster at same 

site during irrigation seasons of earlier years.)

EXTREMES. Sediment load: Maximum, 12,200 tons March 27, 1940; no load on

many days of zero flow.

Sediment concentration: Maximum observed, 3,770 parts per million March 27, 

1940.

DIVERSIONS. Canal diverts water from the Boise River in sec. 3, T. 2 N., R. 

3 E., 8 miles downstream from Moore Creek, for irrigation of approximately 

166,400 acres included in Boise project of Bureau of Reclamation. It is 

used also as a feeder canal for Deer Flat Reservoir near Caldwell. Flow 

regulated by operation of head gates.

Cotton-wood Gulch at Boise, Idaho

LOCATION. Water-stage recorder and broad-crested wooden control structure 

with overfall, with trapezoidal notch for low'stages, lat. 43°37', long. 116°11', 

in SEXSWX sec. 2, T. 3 N., R. 2 E., on United States Military Reservation 

adjacent to city limits and 1 mile east of Boise post office.

DRAINAGE AREA. 16.0 square miles.

DISCHARGE RECORDS. Station established January 25, 1939.

SEDIMENT-LOAD RECORDS. Sediment loads determined from January 27, 1939, 

to June 30, 1940.

EXTREMES. Sediment load: Maximum, 2,610 tons March 21, 1939; minimum,

less than 0.001 ton on many days during periods of low flow. 

Sediment concentration: Maximum observed, 42,000 parts per million March 

19, 1939.

DIVERSIONS. No important diversion above station.
82 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN 

BOISE RIVER NEAR TWIN SPRINGS, IDAHO

Discharge and suspended sediment loads, January 1939 to June 1940

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............

Total . . 

1. .....

2.............

3 ..... .....

4--.--..-.....

5........

6 ........

7 .... .... .

8- .........

9..... ........

10... .........

11 

12............

13 .........

14.... _ .

15... .........

16 ........

17 

18 .......

19.. ...

20............

21 

22........ .

23 .........

24............

15 .......

26. .......

27............

28 ......

29 ......

30. ....

31 .......

Total

January 1939

Discharge 

(secondfeet)

385 

397 

414 

391 

397 

368 

274 

279 

300 

350 

400 

350 

345 

351

374 

368 

374 

379 

385 

362 

306 

252 

263 

334 

374 

397 

440 

430 

400 

350 

300

.........

Sediment 

loads 

(tons)

13 

11 

23 

25 

25 

14 

8.5 

16 

18 

33 

37 

33 

25 

29 

26

336.5

June 1939

1,990 

1,730 

1,600 

1,560 

1,450 

1,320 

1,230 

1,120 

1,200 

1,150 

1,120 

1,140 

1,170 

1,220 

1,160 

1,260 

1,150 

1,050 

1,010 

990 

931 

874 

864 

874 

855 

821 

787 

754 

730 

730

156 

84 

99 

72 

78 

50 

93 

36 

87 

81 

88 

55 

66 

86 

63 

143 

40 

31 

38 

75 

63 

94 

65 

57 

92 

82 

81 

71 

51 

53

2,230

February 1939

Discharge 

(secondfeet)

250 

270 

330 

390 

403 

385 

351 

356 

328 

340 

368 

385 

345 

328 

362 

257 

306 

379 

420 

408 

391 

385 

403 

397 

403 

385 

374 

385

.........

Sediment 

loads 

(tons)

4.0 

14 

17 

35 

44 

15 

10 

14 

13 

24 

29 

14 

15 

14 

16 

5.6 

14 

15 

32 

18 

17 

21 

34 

28 

15 

36 

11 

11

535.6

July 1939

714 

675 

645 

660 

730 

706 

622 

587 

559 

538 

538 

526 

500 

500 

480 

462 

450 

438 

426 

408 

403 

391 

379 

374 

362 

356 

351 

385 

368 

362 

374

... ..... -

21 

27 

49 

48 

34 

38 

34 

32 

23 

22 

41 

41 

34 

34 

26 

25 

22 

18 

25 

22 

18 

18 

20 

15 

11 

14 

12 

26 

20 

9.8 

18

797.8

March 1939

Discharge 

(secondfeet)

379 

368 

368 

356 

351 

345 

356 

351 

362 

379 

408 

426 

468 

462 

450 

462 

566 

730 

931 

1,200 

1,360 

1,550 

1,710 

1,910 

2,040 

2,040 

1,870 

1,810 

1,710 

1,740 

1,800

Sediment 

loads 

(tons) 

24 

19 

18 

12 

20 

18 

12 

8.5 

14 

18 

36 

41 

57 

49 

66 

32 

109 

148 

513 

1,070 

1,270 

1,020 

1,290 

1,830 

1,320 

1.220 

'384 

288 

212 

390 

282

11, 790. 5

August 1939

345 

334 

317 

317 

312 

301 

295 

290 

279 

279 

274 

268 

257 

252 

247 

247 

242 

236 

236 

231 

231 

226 

231 

236 

242 

247 

236 

231 

231 

226 

221

.........

14 

14 

13 

13 

. 13 

12 

12 

12 

11 

11 

8.9 

15 

9.0 

14 

13 

10 

7.8 

7.6 

7.6 

6. 2 

6.2 

6.1 

2.5 

6.4 

7.8 

10 

9.6 

11 

6.2 

3.7 

5.4

299.0

April 1939

Discharge 

(secondfeet)

1,850 

1,990 

2,110 

2, 330 

2,190 

1,870 

1,690 

1,710 

.,730 

1,600 

1,560 

1,570 

1,490 

1,410 

1,480 

1,570 

1,630 

1,820 

2,080 

2,260 

2,540 

2,840 

2,840 

2.760 

2,400 

2,120 

2,120 

2,400 

3,060 

4,120

Sediment 

loads 

(tons)

544 

451 

1,130 

1,670 

917 

894 

940 

540 

411 

363 

114 

110 

129 

95 

80 

153 

114 

236 

500 

677 

1,170 

1,870 

1,070 

850 

473 

412 

280 

467 

2.050 

2,250

20,960

September 1939

221 

226 

231 

231 

236 

231 

226 

231 

226 

221 

221 

295 

438 

374 

334 

306 

279 

263 

257 

247 

247 

247 

242 

242 

242 

247 

242 

242 

247 

252

.........

4.8 

6.1 

6.2 

6.2 

6.4 

6.2 

6.1 

5.0 

4.9 

3.6 

1.2 

2.4 

19 

9.1 

3.6 

1.7 

3.8 

2.1 

2.1 

3.3 

2.7 

2.0 

3.3 

3.3 

2.0 

3.3 

1.3 

4.6 

1.3 

3.4

131.0

May 1939

Discharge 

(secondfeet)

3,950 

3,700 

3,780 

3,860 

3,780 

3,380 

2,990 

2,760 

2,690 

2,760 

2,620 

2,620 

2,540 

2,540 

2,620 

2,760 

2,760 

2,690 

2,690 

2,330 

2,080 

1.920 

1,780 

1,660 

1,560 

1,510 

1,600 

1,830 

2,120 

2,470 

2,330

Sediment 

loads 

(tons)

2,150 

1,700 

1,200 

1,580 

1,530 

694 

444 

373 

291 

447 

248 

382 

411 

343 

297 

268 

291 

443 

552 

315 

236 

166 

168 

134 

164 

139 

138 

267 

246 

327 

359

16,303

October 1939

252 

312 

351 

317 

312 

414 

397 

340 

323 

306 

301 

301 

295 

290 

290 

284 

279 

279 

279 

279 

284 

284 

284 

284 

306 

312 

301 

306 

328 

317 

306

.........

2.0 

2.5 

6.6 

6.0 

7.6 

10 

8.6 

4.6 

4.4 

5.0 

4.9 

5.7 

4.8 

3.9 

7.8 

7.7 

3.0 

3.0 

3.0 

3.0 

3.1 

3.1 

3.1 

3.1 

3.3 

4.2 

4.1 

1.7 

1.8 

6.8 

5.0

143.4
DAILY DISCHARGE AND SEDIMENT LOADS

BOISE RIVER NEAR TWIN SPRINGS, IDAHO Continued

Day

I..... ............. -

2......... . .

3--. .... ... - ...

4.. ............ _ ...

5...... __ .... ___ .

6-- . -._-... _ 

8... ..............

9 . . .

10. ........ ..........

12_. .................

13.. ..............

14- 

15_- _ ---....-.....

16... ...... .......

17. 

18-- 

19 

20-.- -

21...................

22

23 

24... .. .... .

25....... ........ ....

26.. ............ .

27.- ......

28-. ............ ..

29. . .

30-. . . ...

31..-. ........

Total 

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-. ..............

Total. 

. November 1939

Discharge 

(second 

feet)

301 

295 

290 

290 

279 

268 

290 

290 

279 

231 

257 

284 

279 

274 

263 

252 

231 

226 

257 

257 

257 

274 

295 

279 

268 

301 

317 

295 

268 

268

Sediment 

loads 

(tons)

3.3 

3.2 

3.1 

3.1 

3.0 

2.2 

3.9 

5.5 

3.0 

2.5 

2.8 

3.8 

3.8 

4.4 

4.3 

2.0 

1.9 

3.1 

4.9 

6.2 

6.2 

4.4 

4.8 

3.0 

2 9 

2. 4 

2.6 

2.4 

1.4 

3.6

103.7

March 1940

1,200 

1,010 

874 

796 

770 

698 

675 

830 

940 

893 

787 

682 

645 

645 

622 

622 

660 

722 

778 

838 

940 

1,060 

1,230 

1,370 

1,860 

2,690 

4,040 

2,820 

2,260 

2,110 

3,460

117 

87 

. 57 

32 

25 

21 

24 

47 

38 

22 

17 

22 

10 

12 

20 

20 

25 

74 

59 

50 

124 

120 

179 

218 

743 

1,250 

4,570 

944 

323 

308 

1,890

11,448

December 1939

Discharge 

(secondfeet)

284 

284 

284 

268 

252 

323 

312 

295 

379 

594 

512 

432 

374 

362 

356 

462 

706 

566 

420 

426 

408 

351 

317 

317 

268 

180 

220 

270 

330 

397 

403

Sediment 

loads 

(tons)

3.8 

3.8 

4.6 

4.3 

2.7 

4.4 

2.5 

2.4 

3.1 

50 

12 

10 

4.0 

3.9 

4.8 

15 

82 

24 

19 

23 

11 

9.5 

8.6 

12 

11 

5.3 

5.3 

4.4 

8.9 

9.6 

7.6

372.5

April 1940

3,540 

2,820 

2,470 

2,120 

2,030 

1,890 

1,810 

1,730 

1,900 

1,860 

1,820 

1,890 

2,260 

2,820 

3,140 

2,690 

2,470 

2,540 

2,760 

3,060 

2,760 

2,540 

2,540 

2,470 

2,400 

2,540 

2,840 

2,760 

2,540 

2,260

1,060 

457 

400 

143 

132 

133 

103 

75 

133 

100 

118 

138 

262 

929 

1,430 

596 

227 

302 

373 

925 

350 

329 

288 

267 

259 

521 

422 

298 

206 

220

11, 196

January 1940

Discharge 

(secondfeet)

444 

566 

630 

552 

493 

420 

328 

414 

462 

426 

351 

334 

310 

290 

290 

300 

340 

310 

280 

300 

334 

306 

334 

340 

334 

351 

362 

351 

334 

345 

345

Sediment 

loads 

(tons)

12 

35 

34 

27 

16 

11 

11 

18 

19 

15 

5.7 

4.5 

3.3 

7.0 

9.4 

3.2 

7.3 

6.7 

2.3 

5.7 

9.0 

6.6 

6.3 

6.4 

7.2 

11 

15 

9.5 

4.5 

1.9 

9.3

339.8

May 1940

2,080 

2,120 

2,760 

2,990 

2,620 

2,400 

2,330 

2,400 

2,690 

3,300 

4,200 

5,020 

4,830 

4,380 

4,120 

3,780 

3,700 

3,540 

3,540 

3,620 

3,700 

3,700 

3,860 

4,120 

4,200 

4,120 

3,860 

3,540 

3,300 

3,460 

3,620

225 

160 

566 

710 

354 

162 

101 

194 

1,020 

1,170 

3,370 

5,450 

3,830 

1,480 

1,760 

1,320 

1,750 

860 

1,340 

1,450 

1,120 

909 

928 

1,580 

1,670 

1,430 

709 

851 

722 

925 

762

38, 878

February 1940

Discharge 

(secondfeet)

356 

379 

420 

420 

397 

420 

462 

432 

420 

462 

480 

420 

385 

480 

444 

379 

426 

420 

379 

345 

328 

414 

408 

397 

414 

519 

874 

1,450 

1,590

Sediment 

loads 

(tons)

13 

16 

17 

20 

21 

23 

29 

22 

22 

31 

30 

12 

17 

26 

19 

25 

21 

11 

16 

11 

13 

28 

3.3 

11 

10 

42 

349 

846 

305

2, 009. 3

June 1940

3,540 

3,300 

2,990 

2,760 

2,540 

2,330 

2,260 

2,060 

1,850 

1,820 

1,960 

2,260 

2,540 

2,620 

2,330 

2,190 

2,110 

2,040 

1,990 

1,910 

1,670 

1,470 

 1,290 

1,180 

1,100 

1,070 

1,020 

931 

864 

830

698 

642 

476 

410 

411 

239 

220 

267 

165 

69 

116 

220 

329 

396 

201 

95 

68 

99 

97 

52 

59 

48 

31 

32 

27 

23 

19 

10 

12 

16

5,547
84 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

BOISE RIVER AT DOWLING RANCH NEAR ARROW ROCK, IDAHO

Discharge and suspended sediment loads, January 1939 to February 1940

Day

I. .. .......

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.........

Total..

1 

2 

3........ --

4

5_ _ 

6 .

7

8 .

9 ... 

10... .........

11 .

12 

13 _.

14...

16- .......

17 ......

18 ........

19 ......

20 ...

21............

22............

23... ...... .

24 

25. - . .

26- -.

27 

28... ......

29-- .

30 

31 

Total __

January 1939

Discharge 

(secondfeet)

6 

6 

8 

8 

195 

504 

790 

898 

890 

898 

367 

8 

6 

6 

6 

6 

6 

6 

6 

6 

6 

6 

7 

6 

8 

6 

8 

8 

7 

6 

7

Sediment 

loads 

(tons>

0.? 

.08 

.08 

.08 

.08 

.08 

.04 

.05 

.02 

.02 

.02 

.02 

.02 

.02 

.02

.73

June 1939

3,640 

3,540 

3,080 

3,080 

2,990 

2,900 

2,740 

2,650 

2,650 

2,650 

2,570 

2,570 

2,740 

2,900 

2,990 

2,900 

2,740 

2,570 

2,490 

2,490 

2,570 

2,740 

2,820 

2,820 

2,900 

2,900 

2,900 

2,990 

3,080 

3, 170

29 

76 

33 

33 

32 

31 

30 

-36 

50 

43 

35 

42 

37 

47 

65 

55 

74 

42 

47 

40 

42 

15 

30 

23 

23 

16 

31 

16 

33 

17

1,123

February 1939

Discharge 

(secondfeet)

8 

8 

8 

7 

9 

8 

8 

8 

10 

10 

10 

11 

10 

10 

9 

8 

11 

314 

352 

470 

560 

560 

661 

830 

951 

1,030 

1,110 

1,140

Sediment 

loads 

(tons)

0.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.1 

.03 

.05 

.09 

.09 

.08 

.07 

.06 

.1 

3.4 

3.8 

5.1 

6.0 

6.0 

7.1 

9.0 

10 

19 

18 

18

106. 23

July 1939

3,170 

3, 080 

2,990 

2,900 

2,820 

2,740 

2,740 

2,820 

2,820 

2,740 

2,740 

2,740 

2,820 

2,740 

2,740 

2,650 

2,650 

2,650 

2,490 

2,490 

2,340 

2,190 

2,120 

2,190 

2,260 

2,260 

2,260 

2,260 

2,260 

2,260 

2,260

17 

17 

16 

47 

15 

22 

30 

15 

53 

22 

15 

22 

23 

22 

22 

21 

29 

21 

20 

20 

13 

24 

23 

18 

24 

37 

24 

31 

31 

24 

24

742

March 1939

Discharge 

(secondfeet)

1,130 

1,130 

l.ldO 

1,130 

1,120 

1,120 

1,120 

1,160 

1,300 

1,300 

1,220 

1,150 

1,020 

978 

1,000 

1,070 

969 

742 

605 

251 

30 

32 

32 

495 

1,330 

996 

1,000 

1,010 

931 

330 

2,790

Sediment 

loads 

(tons)

12 

24 

40 

55 

39 

24 

12 

6.3 

7.0 

14 

20 

25 

39 

26 

19 

20 

31 

32 

23 

10 

1.3 

2.7 

2.7 

35 

7S 

38 

49 

60 

50 

18 

286

1, 100. 0

August 1939

2,190 

2,260 

2,340 

2,340 

2,340 

2,340 

2,340 

2,340 

2,260 

2,120 

2,120 

2,050 

2,050 

2,120 

2,120 

2,120 

2,120 

2,050 

2,260 

2,260 

2,260 

2,260 

2,260 

2,120 

2,120 

2,190 

1,980 

2,120 

2,190 

1,400 

380

18 

12 

25 

32 

32 

32 

32 

44 

37 

34 

46 

83 

11 

34 

29 

34 

29 

44 

43 

55 

37 

37 

43 

52 

46 

53 

69 

86 

53 

30 

8.2

1, 170. 2

April 1939

Discharge 

(secondfeet)

4,660 

5,100 

5,100 

5,220 

5,340 

5,220 

4, 550 

3,440 

3,440 

3,730 

3,640 

3,540 

3,440 

3, 350 

3,350 

3,440 

3,830 

4,240 

4,340 

4,240 

4,240 

4,240 

4,340 

4,240 

4,240 

4,240 

4,340 

4,440 

4,440 

4,660

Sediment 

loads 

(tons)

478 

523 

413 

296 

274 

240 

160 

84 

195 

282 

275 

105 

186 

118 

136 

241 

196 

218 

246 

206 

252 

126 

70 

103 

126 

103 

82 

120 

132 

340

6,326

September 1939

380 

366 

366 

330 

510 

712 

1,230 

1,780 

1,980 

2,050 

2,420 

2,420 

2,120 

2,050 

1,720 

1,160 

415 

380 

380 

352 

334 

344 

366 

362 

339 

529 

996 

1,470 

1,590 

1,650

7.2 

8.9 

5.9 

7.1 

15 

27 

46 

48 

86 

77 

78 

78 

74 

105 

93 

63 

29 

23 

24 

21 

18 

17 

14 

15 

15 

23 

38 

64 

69 

89

1, 278. 1

May 1939

Discharge 

(secondfeet)

5,690 

6,710 

6,980 

7,2oO 

7,250 

6,980 

6,190 

5,690 

5,340 

5,220 

5,220 

5,100 

4,880 

4,770 

4,880 

4,990 

5,100 

4,990 

4,990 

4,770 

4,240 

3,930 

3,830 

3,640 

3,440 

3,170 

3,170 

3,170 

3,260 

3,540 

3,730

Sediment 

loads 

(tons)

338 

417 

415 

313 

450 

471 

301 

200 

144 

113 

113 

69 

67 

64 

02 

54 

96 

81 

81 

77 

57 

42 

31 

98 

 28 

34 

34 

26 

26 

29 

40

4,401

October 1939

1,410 

528 

516 

447 

322 

290 

340 

528 

480 

474 

498 

516 

492 

492 

492 

510 

528 

528 

522 

417 

236 

240 

240 

562 

847 

1,040 

1,220 

1,410 

1,360 

1,260 

1,140

126 

48 

50 

47 

37 

25 

37 

57 

53 

41 

47 

33 

31 

27 

20 

21 

21 

71 

24 

30 

19 

21 

16 

27 

48 

56 

79 

91 

55 

44 

49

1,351
DAILY DISCHARGE AND SEDIMENT LOADS 85 

BOISE RIVER AT DOWLING RANCH NEAR ARROW ROCK, IDAHO Continued

Day

1.. __ . _ ... .....

2.. ..................

3.... -. .

4...................

5--- .- ........

6... ..............

7..-... ..........

8.....- ..........

9- . ....... ........

10...................

u.. .................

12...................

13... .............

14........ ........

15.. ..............

16.-- ___ ... .... .

17...................

IS...................

19....... ....... .....

20...................

21...................

22 .

23---..-.. __ .......

24-.... ...........

25.. ........ ...... ...

26...................

27-- 

28..-... .........

29..... ...... ....... .

30---- ... ...... .

31 ..

Total-.-, ._..

November 1939

Discharge 

(secondfeet)

513 

8 

5 

4 

4 

4 

4 

4 

4 

4 

4 

4 

4 

4 

4 

4 

4 

4 

4 

289 

654 

942 

1,060 

1,070 

1,060 

1,050 

1,110 

1, 140 

1,130 

1,110

Sediment 

loads 

(tons)

40 

.3 

.1 

.09 

.01 

.05 

.05 

.05 

.03 

.03 

.03 

.03 

.2 

.2 

.2 

.2 

.2 

.04 

.04 

3.1 

7.1 

10 

5.7 

5.8 

11 

5.7 

9.0 

15 

12 

12

138.25

December 1939

Discharge 

(secoradfeet)

1,120 

1,120 

1,090 

1,100 

1,100 

1,110 

1,120 

1,120 

1,120 

1,120 

1,110 

1,120 

1,120 

1,110 

1,130 

469 

8 

6 

5 

6 

5 

5 

5 

5 

4 

4 

4 

4 

4 

5 

5

Sediment 

loads 

(tons)

18 

18 

18 

18 

18 

24 

30 

21 

33 

18 

33 

36 

48 

45 

46 

25 

.3 

.1 

.2 

.2 

.1 

.08 

.07 

.05 

.04 

.04 

.05 

.05 

.05 

.3 

.3

450. 93

January 1940

Discharge 

(secondfeet)

6 

7 

8 

8 

6 

6 

5 

5 

6 

6 

5 

5 

4 

4 

5 

4 

5 

4 

4 

4 

4 

4 

4 

4 

5 

6 

6 

6 

5 

5 

5

Sediment 

loads 

(tons)

0.4 

.2 

.2 

.2 

.06 

.08 

.07 

.01 

.1 

.1 

.1 

.1 

.05 

.05 

.07 

.04 

.05 

.02 

.03 

.03 

.05 

.02 

.04 

.04 

.05 

.08 

.08 

.08 

.07 

.07 

.07

2.61

February 1 940

Discharge 

(serondfcet)

5 

5 

6 

7 

6 

8 

8 

91 

344 

566 

640 

774 

915 

951 

951 

942 

933 

933 

933 

933 

933 

933 

856 

750 

750 

735 

403 

29 

29

Sediment 

loads 

(tons)

0.07 

.07 

.08 

.2 

.2 

.2 

.3 

4.7 

9.3 »26 

16 

21 

25 

31 

21 

20 

13 

15 

13 

13 

10 

25 

23 

20 

18 

20 

32 

2.5 

13

392. 62

Total sediment loads reported on and after Feb. 10,1940.

Discharge and total sediment loads, March to June 1940

Day

1.. . ........

2 

4

5... .

7-. .--- ...

8-.... .... .

9-. . .... ....

10-- 

11.-- _ ...

12 

is

14--..-.- __ ... ....

16.. ..

17..... ........

18--... ......

19. 

20-- .. 

21- 

99

23 

24-. 

25 

26 

27 

28.- 

29-- 

30-- 

31 

Total _ . _ ..

March 1940

25 

24 

20 

18 

104 

290 

385 

400 

298 

302 

366 

474 

586 

626 

626 

626 

280 

9 

8 

8 

8 

8 

8 

8 

48 

64 

12 

10 

10 

10 

16

15 

5.1 

6.8 

1.0 

21 

29 

15 

14 

13 

8.2 

7.9 

24 

38 

25 

19 

29 

6.0 

.2 

.2 

.3 

.4 

.3 

.6 

.5 

3.2 

1.4 

.5 

.6 

.5 

.3 

1.1

287.1

April 1940

20 

396 

1,850 

3,350 

4,660 

4,440 

3,830 

3,640 

3,640 

3,260 

3,080 

3,170 

3,930 

5,100 

5,940 

5,820 

5,340 

5,450 

5,940 

6,450 

6,450 

6,190 

5,340 

4,880 

5,100 

5,220 

5,340 

5,570 

5,450 

5,340

1.6 

53 

325 

724 

1,110 

468 

372 

216 

354 

308 

216 

154 

265 

716 

690 

471 

360 

368 

593 

923 

418 

501 

260 

198 

262 

268 

231 

256 

206 

260

11, 547. 6

May 1940

4,880 

4,660 

4,660 

4,770 

4,990 

4,990 

4,880 

4,770 

4,990 

5,570 

6,580 

8,090 

8,960 

8,380 

8,090 

7,530 

7,250 

6,840 

6,580 

6,710 

6,710 

6,710 

6,840 

7,250 

7,530 

7,250 

6,980 

6,580 

6,060 

6,060 

6,320

211 

377 

252 

270 

216 

189 

145 

180 

202 

271 

391 

1,140 

968 

1,270 

786 

529 

744 

295 

409 

308 

399 

326 

388 

215 

264 

215 

415 

284 

213 

131 

171

12, 174

June 1940

6,450 

6,060 

5,570 

5,340 

4,990 

4,550 

4,340 

4,030 

3,730 

3,540 

3,540 

3, 730 

4,030 

4,240 

3,930 

3,830 

3,830 

3,830 

3,830 

3,830 

3,830 

3,730 

3,640 

3,640 

3,540 

3,640 

3,730 

3,640 

3,540 

3,540

139 

131 

105 

101 

121 

74 

94 

76 

70 

86 

124 

161 

98 

149 

85 

62 

72 

124 

114 

62 

134 

111 

98 

128 

86 

79 

131 

108 

96 

76

3,095
86 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

BOISE RIVER AT NOTUS, IDAHO

Discharge and suspended sediment loads, January 1939 to June 1940

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 

Total .

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 

TotalJanuary 1939

Discharge 

(secondfeet)

540 

555 

550 

540 

555 

540 

496 

474 

465 

457 

457 

461 

540 

520 

520 

520 

501 

501 

515 

520 

510 

492 

470 

478 

470 

483 

510 

550 

535 

540 

525

Sediment 

loads 

(tons)

58 

49 

65 

60 

47 

28 

33 

38 

28 

25 

28 

36 

33 

27 

43 

91 

66 

63 

61

879

June 1939

46 

43 

38 

38 

38 

40 

46 

43 

43 

42 

42 

42 

40 

36 

36 

44 

47 

49 

60 

63 

51 

46 

40 

34 

28 

32 

34 

36 

32 

34

3.7 

3.5 

3.4 

3.4 

4.3 

3.6 

4.0 

3.4 

2.7 

2.0 

2.6 

2.4 

1.9 

1.7 

1.7 

2.9 

2.7 

3.2 

5.3 

3.6 

3.4 

3.9 

2.9 

2.8 

2.8 

2.0 

2.2 

2.5 

1.6 

2.3

88.4

February 1939

Discharge 

(secondfeet)

488 

457 

453 

488 

501 

515 

515 

510 

461 

496 

474 

496 

535 

550 

602 

690 

596 

566 

535 

488 

461 

488 

515 

506 

461 

441 

433 

433

Sediment 

loads 

(tons)

65 

52 

46 

45 

47 

60 

42 

62 

41 

33 

40 

42 

55 

67 

80 

281 

109 

90 

72 

46 

36 

41 

53 

49 

35 

27 

22 

18

1,656

July 1939

44 

45 

40 

40 

43 

47 

44 

36 

31 

36 

40 

38 

38 

34 

29 

30 

34 

32 

34 

34 

32 

25 

25 

22 

25 

24 

26 

19 

17 

18 

18

2.5 

3.5 

3.0 

2.3 

2.1 

2.0 

1.2 

1.7 

1.8 

1.7 

2.9 

1.3 

1.4 

3.4 

1.5 

4.4 

1.3 

.8 

.9 

2.1 

1.4 

1.7 

1.2 

.8 

.8 

1.3 

1.3 

.8 

.7 

1.3 

1.1

54.2

March 1939

Discharge 

(secondfeet)

425 

429 

437 

433 

418 

418 

422 

394 

372 

372 

375 

414 

555 

506 

441 

429 

478 

535 

555 

560 

924 

1,480 

1,620 

1,760 

2,480 

3,340 

3,080 

2,660 

2,000 

1,260 

853

Sediment 

loads 

(tons)

15 

22 

24 

23 

11 

27 

15 

16 

20 

17 21- 

88 

469 

245 

148 

104 

274 

423 

581 

558 

1,350 

2,730 

2,590 

2,670 

6,960 

7,480 

3,290 

2,010 

1,470 

538 

419

34, 608

August 1939

18 

18 

20 

26 

31 

26 

24 

26 

27 

28 

29 

25 

24 

36 

23 

19 

19 

21 

21 

21 

19 

18 

19 

19 

20 

22 

22 

26 

23 

25 

25

0.7 

.6 

.3 

.8 

1.4 

1.0 

1.2 

1.0 

2.0 

1.7 

.7 

1.2 

.7 

1.4 

.8 

.6 

1.0 

1.1 

.9 

.9 

3.1 

.7 

.8 

1.5 

.9 

.7 

1.2 

2.5 

4.3 

2.1 

3.3

41.1

April 1939

Discharge 

(secondfeet)

3,760 

5,360 

5,540 

5,730 

5,490 

4,950 

4,410 

3,460 

2,110 

2,000 

1,560 

1,190 

897 

660 

382 

250 

121 

86 

133 

150 

111 

71 

75 

105 

123 

96 

52 

47 

45 

170

Sediment 

loads 

(tons)

8,120 

8,600 

6,430 

5,150 

4,210 

2,910 

2,050 

1,640 712 

643 

388 

254 

179 

109 

47 

29 

12 

8.1 

10 

13 

7.5 

6.6 

5.1 

9.1 

7.6 

7.0 

2.0 

1.8 

1.3 

12

41,574.1

September 1939

24 

25 

25 

27 

25 

27 

32 

31 

29 

29 

29 

32 

46 

425 

530 

378 

444 

386 

262 

250 

215 

158 

129 

102 

79 

66 

58 

55 

50 

46

1.6 

2.2 

3.0 

5.4 

4.3 

5.7 

3.2 

4.1 

2.4 

2.5 

4.0 

9.3 

5.2 

90 

64 

34 

68 

28 

16 

11 

14 

6.0 

26 

12 

10 

7.5 

7.2 

8.3 

6.9 

5.2

467.0

May 1939

Discharge 

(secondfeet)

645 

1,700 

2,530 

2,870 

2,870 

2,780 

2,440 

1,740 

1,110 

839 

768 

724 

615 

530 

444 

404 

630 

763 

686 

785 

655 

448 

274 

253 

188 

109 

90 

76 

49 

44 

42

Sediment 

loads 

(tons)

226 

1,040 

1,370 

1,460 

1,130 

946 

712 

404 

216 

145 

108 

88 

65 

50 

36 

36 

87 

127 

85 

129 

95 

41 

21 

21 

14 

8.3 

5.1 

5.3 

3.2 

4.5 

4.1

8, 682. 5

October 1939

75 

168 

265 

220 

223 

226 

200 

178 

244 

190 

190 

175 

165 

129 

121 

101 

96 

87 

90 

95 

93 

121 

96 

120 

217 

520 

570 

560 

530 

520 

520

10 

23 

36 

23 

30 

35 

16 

20 

32 

21 

20 

19 

20 

15 

14 

10 

9.3 

11 

11 

11 

12 

13 

9.8 

13 

56 

119 

62 

76 

86 

79 

66

978.1
DAILY DISCHARGE AND SEDIMENT LOADS 87

BOISE RIVER AT NOTUS, IDAHO Continued

Day

1..... __ _ ...

2...... ..............

3..- ........ ... 

4. ................. ..

6....................

7....... ...... .......

8-.... ......... ...

9...... ........ 

10.. ............... ..

11.. .. ...............

l^.. .................

13-..- ........ ....

14...................

16--. 

17.-- 

18-.- - . 

19..- 

20.. ....- 

21-..- . .

22..-- . 

23.. 

24-.- .

25..- . ... ...

26-.- 

27-- 

28..- - . 

29...- . .

30-.- q-i

Total 

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..... .

Total 

November 1939

Discharge 

(secondfeet)

525 

525 

590 

570 

565 

560 

555 

545 

540 

530 

525 

520 

525 

520 

516 

516 

512 

507 

507 

502 

502 

484 

466 

458 

453 

453 

453 

444 

440 

435

Sediment 

loads 

(tons)

31 

34 

45 

34 

26 

30 

51 

37 

34 

33 

33 

27 

38 

35 

40 

45 

33 

37 

23 

57 

35 

51 

28 

22 

24 

108 

35 

19 

23 

25

1 OQ^

March 1940

708 

615 

605 

545 

520 

502 

489 

507 

507 

480 

484 

471 

462 

453 

448 

448 

435 

516 

821 

871 

910 

938 

945 

686 

489 

489 

686 

1,440 

815 

615 

635

474 

296 

265 

155 

136 

108 

107 

104 

182 

80 

68 

65 

110 

55 

79 

65 

48 

68 

483 

513 

523 

582 

536 

280 

114 

103 

335 

5,050 

907 

329 

974

13, 194

December 1939

Discharge 

Csecondfeet)

430 

430 

426 

417 

417 

417 

417 

417 

430 

430 

412 

394 

399 

399 

399 

399 

399 

502 

550 

545 

520 

516 

498 

484 

471 

440 

448 

453 

466 

480 

507

Sediment 

loads 

(tons)

22 

21 

20 

27 

27 

16 

21 

118 

38 

43 

31 

29 

23 

31 

25 

41 

36 

91 

92 

147 

131 

116 

101 

84 

102 

95 

96 

83 

89 

93 

105

1,994

April 1940

1,010 

1,210 

1,300 

2,660 

4,240 

5,410 

4,860 

4,330 

4,500 

4,500 

3,820 

3,500 

3,420 

4,500 

5,600 

5,980 

-, 600 

4,860 

4,680 

4,500 

4,860 

4,240 

3,580 

2,100 

1,500 

1,440 

1,440 

1,550 

2,440 

2,440

2,780 

1,370 

1,540 

5,410 

7,260 

6,560 

3,710 

2,330 

2,130 

2,020 

1,640 

1,610 

2,970 

2,760 

3,760 

3,390 

2,980 

2,130 

1,760 

1,880 

2,550 

1,730 

1,940 

714 

332 

327 

268 

402 

1,590 

975

70, 818

Januar

Discharge 

fsecond- 

' feet)

545 

605 

650 

719 

620 

489 

458 

476 

575 

590 

650 

480 

466 

498 

502 

480 

484 

489 

408 

507 

494 

498 

498 

502 

498 

512 

590 

595 

565 

550 

535

y 1940

Sediment 

loads 

(tons)

160 

185 

258 

460 

330 

111 

87 

63 

88 

124 

101 

70 

73 

75 

77 

84 

90 

95 

68 

97 

87 

112 

83 

94 

98 

135 

180 

177 

149 

143 

124

4,078

May 1940

2,160 

1,660 

1,400 

1,330 

1,270 

1,330 

996 

724 

545 

575 

938 

2,230 

3,990 

4,680 

3,900 

3,740 

3, 180 

2,960 

2,800 

2,510 

2,510 

2,440 

2,370 

2,730 

3,030 

3,340 

3,100 

2,880 

2,440 

1,840 

1,900

589 

368 

299 

280 

226 

262 

137 

90 

63 

79 

238 

1,470 

2,210 

2,500 

1,520 

1,600 

996 

823 

635 

508 

352 

560 

608 

973 

. 859 

1,720 

 1, 100 

809 

659 

348 

328

23,209

February 1910

Discharge 

(socondfeet)

530 

525 

535 

545 

560 

575 

545 

555 

458 

453 

458 

435 

435 

480 

480 

466 

458 

480 

471 

458 

444 

448 

466 

466 

476 

555 

625 

675 

635

Sediment 

loads 

(tons)

102 

105 

88 

141 

150 

199 

174 

172 

110 

76 

72 

62 

45 

45 

56 

60 

28 

32 

52 

46 

42 

68 

92 

128 

105 

500 

790 

822 

360

4,722

June 1940

2,100 

2,230 

1,900 

1,410 

1,220 

884 

590 

378 

235 

165 

131 

109 

76 

111 

70 

65 

43 

34 

38 

28 

25 

25 

25 

30 

26 

24 

24 

21 

24 

26

352 

391 

349 

236 

119 

95 

57 

23 

12 

5.3 

5.7 

2.1 

1.4 

3.0 

2.1 

1.9 

1.3 

1.0 

1.3 

1.0 

1.0 

1.0 

1.0 

.8 

.7 

.6 

.6 

.6 

.7 

.8

1, 667. 9
DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

COTTONWOOD CREEK AT ARROW ROCK RESERVOIR, IDAHO

Discharge and total sediment loads, January 1939 to June 1940

Day

1

2-. ...--

3 

4

5- ------

7

8_ -

9--- ---

10 

11 

13 

14 

15--. --..-

16-. ------

17 

18 

19 .

20 

21. .

22.. .... .... .-

23 

24 --

25 

26 

27 

28 

29... 

30 

31. ........ ...

2.... - -- 

3 

4 

5 

7_-_--.---..-.

8 -------

9

10 

11 

12 

13...... -.-.

14 

15 

16 ....-.

17 

18 

19 

20 

21 __ 

23 .

24____. ......

25 

26 

27 

28-. ------

29..... ..

30 

31 

Total. .

January 1939

Discharge 

(secondfeet)

4.5 

4.5 

4.5 

4.6 

4.9 

4.9 

4.9

4.4

4.0

Sediment 

loads 

<tons)

0.6 

.3 

.2 

.02 

.04 

.01 

.08

.06

.06

1.37

June 1939

6.0 

5.5 

6.0 

5.7 

6.0 

7.0 

6.7 

6.0 

6.0 

5.5 

5.2 

4.9 

4.4 

4.2 

4.2 

4.6 

4.6 

4.9 

5.2

5.2 

4.4 

4.2 

3.8 

3.8 

3.6 

3.4 

3.2 

2.2 

2.2 

2.2

.........

0.4 

.2 

.3 

.4 

.4 

.4 

.2 

.2 

.2 

.1 

.2 

.2 

.1 

.1 

.3 

.1 

.1 

.2 

.5 

.2 

.1 

.1 

.3 

.1 

.1 

.09 

.09 

.08 

.08 

.08

5.92

February 1939

Discharge 

(secondfeet)

4.0 

4.3 

4.3 

4.3 

4.0 

4.3 

4.3 

4.3 

4.0 

4.3 

3.8 

4.4 

4.0 

4.2 

4.6 

4.4 

4.4 

4.4 

4.6 

4.5 

4.5 

4.6 

4.6 

4.6 

5.2 

4.9 

4.9 

5.2

Sediment 

loads 

(tons)

0.08 

.09 

.06 

.06 

.04 

.06 

.06 

.06 

.06 

.1 

.05 

.04 

.1 

.05 

.06 

.01 

.09 

.07 

.08 

.05 

.07 

.1 

.2 

.09 

.3 

.08 

.dS 

.2.

2.36

July 1939

2.1 

2.0 

2.0 

2.3 

3.0 

2.8 

2.3 

1.9 

1.8 

1.6 

1.6 

1.4 

1.3 

1.1 

1.1 

1.1 

.95 

.90 

.84 

.78 

.73 

.73 

.73 

.73 

.73 

.67 

.53 

.53 

.62 

.67 

.67

0.04 

.04 

.04 

.06 

.08 

.08 

.1 

.1 

.1 

.09 

.09 

.03 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.01 

.007 

.008 

.009 

.009

1.173

March 1939

Discharge 

(secondfeet)

5.2 

5.5 

5.5 

5.5 

5.1 

5.5 

5.5 

5.5 

5.5 

6.3 

7.0 

8.4 

10 

10 

1011

16 

23 

29 

34 

39 

42 

44 

49 

53 

53 

49 

45 

43 

43 

44

Sediment 

loads 

(tons)

0.04 

.04 

.04 

.03 

.07 

1.2 

1.4 

.3 

.2 

1.3 

.4 

1.4 

1.2 

1.1

!g

2.1 

7.9 

6.7 

15 

19 

18 

9.0 

18 

39 

27 

21 

14 

11 

7.4 

12

237.82

August 1S39

0.62 

.57 

.53 

.53 

.53 

.48 

.48 

.48 

.48 

.44 

.35 

.35 

.35 

.35 

.35 

.39 

.35 

.35 

.35 

.35 

.35 

.32 

.32 

.32 

.32 

.32 

.32 

.35 

.35 

.39 

.32

0.008 

.005 

.004 

.004 

.004 

.004 

.006 

.006 

.006 

.006 

.005 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.003 

.003 

.003 

.003 

.003

0.133

April 1939

Discharge 

(secondfeet)

46 

47 

49 

49 

44 

39 

36 

35 

35 

34 

34 

33 

30 

30 

31 

31 

31 

32 

33 

35 

36 

37 

36 

33 

29 

28 

29 

31 

33 

35

Sediment 

loads 

(tons)

15 

13 

11 

24 

23 

15 

6.7 

10 

7.7 

9.5 

8.3 

6.6 

4.3 

2.9 

3.8 

3.5 

11 

5.3 

15 

11 

23 

21 

22 

22 

27 

16 

13 

9.5 

8.2 

14

382.3

September 1939

0.32 

.32 

.35 

.35 

.39 

.39 

.35 

.39 

.39 

.44 

.44 

1.0 

2.2 

1.6 

1.2 

1.2 

1.1 

1.1 

.95 

.89 

.83 

.83 

.89 

.95 

1.0 

1.0 

1.1 

1.0 

1.1 

1.1

0.009 

.009 

.01 

.01 

.01 

.008 

.008 

.008 

.008 

.001 

.002 

.2 

.3 

.004 

.006 

.03 

.01 

.01 

.01 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02

0.873

May 1939

Discharge 

(secondfeet)

32 

29 

26 

26 

22 

22 

20 

19 

19 

18 

17 

15 

15 

14 

14 

13 

13 

12 

12 

12 

11 

12 

12 

10 

10 

9.6 

8.8 

7.6 

7.0 

6.7 

5.7

Sediment 

loads 

(tons)

19

4.6 

7.3 

7.6 

5.9 

5.0 

4.0 

3.5 

2.5 

2.3 

3.1 

2.0 

2.5 

1.7 

1.6 

1.5 

1.3 

.9 

2.1 

2.2 

1.8 

.6 

.9 

.8 

.8 

.4 

.4 

.4 

.4 

.3 

.5

87.9

October 1939

1.1 

1.5 

2.3 

1.9 

1.8 

3.2 

2.3 

1.9 

1.8 

1.8 

1.8 

1.7 

1.7 

1.5 

1.5 

1.5 

1.7 

1.8 

1.8 

1.8 

1.8 

1.8 

1.8 

1.8 

2.0 

2.0 

2.0 

2.1 

2.2 

2.2 

2.1

.........

0.02 

.01 

.1 

.02 

.01 

.1 

.06- 

.03 

.02 

.03 

.01 

.01 

.04 

.02 

.02 

.008- 

.01 

.01 

.01 

.01 

.01 

.01 

.01 

.01 

.02 

.02 

.02 

.01 

.01 

.01 

.01

0.688
DAILY DISCHARGE AND SEDIMENT LOADS 89

COTTONWOOD CREEK AT ARROW ROCK RESERVOIR, IDAHO Continued

Day

«

1_. .. ................

3. ........ ....... ....

4... .... _____ ---_

5.--..--.-.... -.-.

6 _ ...-

8 _ 

9 

10-. 

12 - -

13.. --

15-... .......... -

16___. ...............

17..- .. --

18-- 

19..- 

20..- 

21... 

22... -------------

24--. 

25. .- 

26-- 

27-- 

28- 

29 

30- 

31 

Total .

I.... 

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... .........

TotalNovember 1939

Discharge 

(secondfeet)

2.2 

2.1 

2.1 

2.1 

2.1 

2.0 

2.0 

2.1 

2.0 

1.9 

2.1 

2.2 

2.1 

2.0 

2.0 

2.1 

2.0 

2.2 

2.2 

2.2 

2.2 

2.3 

2.3 

2.3 

2.3 

2.3 

2.4 

2.3 

2.3 

2.4

Sediment 

loads 

(tons)

0.01 

.01 

.01 

.01 

.006 

.005 

.005 

.006 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.01 

.01 

.01 

.01 

.01 

.006 

.006 

.006 

.006 

.02 

.02 

.02 

.02 

.01

0.386

March 1940

37 

32 

27 

25 

23 

20 

19 

22 

21 

20 

18 

16 

14 

14 

14 

14 

16 

18 

19 

20 

22 

23 

24 

26 

38 

51 

68 

48 

42 

43 

57

70 

50 

24 

15 

13 

9.8 

11 

10 

8.2 

10 

3.4 

4.3 

7.4 

5.8 

2.4 

1.3 

2.8 

9.4 

8.8 

7.7 

7.0 

9.3 

5.3 

11 

62 

182 

609 

1,080 

480 

366 

594

3, 679. 9

December 1939

Discharge 

(secondfeet)

2.4 

2.4 

2.3 

2.3 

2.3 

3.5 

2.9 

2.9 

4.2 

4.4 

4.9 

3.6 

3.5 

3.0 

3.2 

4.0 

5.2 

3.8 

3.2 

3.6 

3.4 

2.4 

2.9 

2.9 

1.7 

2.3 

3.0 

2.5 

2.7 

3.0 

3.6

Sediment 

loads 

(tons)

0.02 

.02 

.02 

.02 

.02 

.06 

.05 

.05 

.3 

.2 

.3 

.07 

.06 

.05 

.07 

.06 

.07 

.06 

.03 

.03 

.02 

.02 

.09 

.09 

.05 

.07 

.09 

.05 

.03 

.03 

.2

2.30

April 1940

62 

57 

51 

48 

48 

46 

46 

45 

47 

45 

43 

44 47' 

53 

49 

45 

40 

39 

40 

40 

35 

33 

31 

30 

29 

32 

37 

32 

30 

27

625 

405 

197 

332 

146 

162 

164 

142 

138 

144 

50 

49 

99 

121 

121 

54 

66 

77 

107 

73 

42 

44 

25 

33 

43 

50 

54 

42 

32 

26

3,663

January 1940

Discharge 

(secondfeet)

5.2 

8.0 

7.3 

6.0 

5.2 

3.8 

3.6 

4.4 

4.9 

4.9 

4.4 

4.4 

3.4 

4.2 

3.4 

3.6 

4.0 

3.6 

3.4 

3.7 

3.6 

3.5 

3.4 

3.4 

3.4 

4.2 

 4.2 

4.0 

4.0 

4.0 

4.0

Sediment 

loads 

(tons)

0.3 

2.2 

.5 

.1 

.08 

.02 

.06 

.01 

.08 

.06 

.05 

.04 

.04 

.05 

.04 

.02 

.02 

.02 

.04 

.04 

.04 

.009 

.009 

.009 

.04 

.2 

.02 

.02 

.03 

.03 

.03

4.207

May 1940

26 

26 

27 

26 

24 

22 

23 

23 

24 

26 

26 

26 

26 

24 

24 

22 

21 

20 

18 

18 

17 

16 

16 

15 

14 

14 

21 

12 

12 

11 

10

42 

76 

49 

31 

14 

12 

11 

21 

22 

19 

29 

20 

17 

11 

7.0 

9.7 

5.0 

3.8 

3.4 

3.1 

2.8 

2.3 

1.7 

1.8 

1.3 

1.2 

1.7 

1.3 

1.3 

1.0 

.8

423.2

February 1940

Discharge 

(secondfeet)

4.0 

4.0 

4.6 

4.9 

4.6 

8.0 

7.0 

6.0 

6.0 

7.6 

8.0 

6.7 

6.7 

7.0 

6.7 

5.7 

6.3 

6.0 

5.7 

5.2 

5.2 

6.3 

6.3 

6.0 

7.6 

12 

25 

47 

46

Sediment 

loads 

(tons)

0.05 

.05 

.06 

.1 

.1 

1.8 

.4 

.1 

.8 

.4 

.3 

.9 

.3 

.3 

.3 

.5 

.2 

.2 

.6 

.6 

.7 

.2 

.3 

.1 

.7 

5.2 

30 

162 

77

284.26

June 1940

10 

9.6 

9.3 

10 

9.3 

8.3 

8.6 

8.6 

7.7 

7.4 

6.9 

5.8 

5.5 

5.5 

5.0 

5.0 

4.3 

4.2 

3.5 

3.4 

3.4 

3.2 

2.9 

2.1 

2.1 

1.9 

1.8 

1.9 

1.9 

1.8

0.5 

.5 

.4 

.4 

.4

;4

.3 

.2 

.2 

.3 

.5 

.2 

.5 

.1 

.6 

.2 

.2 

.2 

.2 

.2 

.05 

.04 

.04 

.03 

.03 

.04 

.04 

.04 

.04 

.04

6.89
90 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

GROUSE CREEK NEAR ARROW ROCK, IDAHO

Discharge and sediment loads, January 1989 to June 1940

Day

1

2_- ___.- __-

4

5

6

7. - --

8.. ......... --

9-_ ....... --

10 -

11 

13 

14-. -------

16 

17 -

18 

19-... -.-..--

20----- - ---

91

23 -

26 

27 

29 -

on

31 

Total 

3_ -----

4 -

6 

7 

8 

9 . -----

10-- - -

13- 

14- -

16 

17... ....... ..

18 

19 

20 

21 

22- 

23 

24 

25 

26. 

27 

28 

29 

30 -..

31 

Total- -

January 1939

Discharge 

(secondfeet)

1.1 

1.1

1.1 

1.1 

.90 

.90 

1.0 

1.1 

1.1 

1.1 

1.1 

.87

Sediment 

loads 

(tons)

0.3 

.4 

.4 

.5 

.3 

.2 

.1 

.3 

.3 

.3 

.2 

.3

June 1939

1.1

1.1 

1.1 

1.1 

1.1 

1.1 

1.1 

1.1 

1.1 

1.0 

.98 

.93 

.83 

.83 

.93 

1.0 

1.0 

1.0 

1.1 

1.0 

.93 

.88 

.78 

.78 

.78 

.78 

.78 

.74 

.69 

.69

 

0.04 

.01 

.02 

.03 

.04 

.04 

.03 

.03 

.03 

.04 

.04 

.05 

.01 

.01 

.02 

.02 

.02 

.03 

.04 .04' 

.02 

.02 

.02 

.02 

.02 

.02 

.05 

.04 

.04 

.02

0.86

February 1939

Discharge 

(secondfeet)

0.90 

.99 

1.1 

1.2 

1.1 

1.2 

1.2 

1.1 

1.0 

1.1 

1.2 

1.3 

1.3 

1.4 

1.5 

1.4 

1.6 

1.6 

1.6 

1.5 

1.6 

1.7 

2.0 

2.0 

2.4 

2.5 

2.4 

2.7

Sediment 

loads 

(tons)

0.5 

.4 

.4 

.3 

.3 

.3 

.3 

.3 

.4 

.3 

.5 

.5 

.5 

.6 

.8 

12 

25 

24 

15 

3.5 

4.0 

8.1 

6.3 

8.1 

17 

21 

16 

95

261.4

July 1939

0.64 

.64 

.59 

.69 

.74 

.64 

.59 

.54 

.49 

.47 

.54 

.54 

.59 

.54 

.54 

.59 

.49 

.44 

.44 

.44 

.34 

.34 

.34 

.29 

.24 

.24 

.30 

.34 

.34 

.34 

.34

 

0.02 

.02 

.01 

.02 

.02 

.02 

.02 

.02 

.02 

.01 

.01 

.01 

.006 

.006 

.006 

.006 

.005 

.005 

.004 

.004 

.003 

.003 

.003 

.005 

.005 

.005 

.006 

.006 

.006 

.005 

.005

0.294

March 1939

Discharge 

(secondfeet)

3.0 

2,5 

2.4 

2.4 

2.3 

2.3 

2.2 

2.0 

2.1 

3.0 

4.5 

6.5 

9.7 

5.7 

4.5 

7.7 

12 

15 

23 

27 

33 

38 

43 

42 

40 

34 

31 

28 

29 

22 

24

Sediment 

loads 

(tons)

45 

5.4 

3.7 

2.2 

19 

8.2 

20 

4.0 

10 

56 

87 

155 

415 

170 

176 

577 

749 

816 

1,720 

2,030 

2,850 

1,570 

2,120 

1,520 

1,570 

1,850 

3,950 

1,470 

931 

369 

385

25, 653. 5

August 1939

0.29 

.29 

.29 

.32 

.29 

.24 

.24 

.24 

.20 

.24 

.24 

.20 

.20 

.24 

.28 

.24 

.24 

.24 

.24 

.29 

.34 

.34 

.34 

.34 

.31 

.29 

.29 

.29 

.29 

.29 

.34

.........

0.004 

.004 

.008 

.02 

.02 

.01 

.01 

.01 

.01 

.006 

.006 

.005 

.005 

.006 

.007 

.005 

.005 

.005 

.005 

.005 

.006 

.004 

.004 

.004 

.003 

.003 

.003 

.003 

.003 

.003 

.003

0.195

April 1939

Discharge 

(secondfeet)

24 

20 

18 

16 

13 

13 

11 

10 

9.7 

9.1 

8.5 

8.1 

7.7 

7.3 

6.9 

6.5 

6.1 

6.1 

5.3 

4.9 

4.4 

4.2 

4.2 

4.1 

3.7 

3.4 

3.2 

3.0 

3.2 

3.1

Sediment 

loads 

(tons)

606 

454 

214 

243 

49 

37 

16 

28 

13 

14 

9.2 

4.2 

4.9 

5.2 

1.6 

3.1 

1.3 

.6 

.6 

.4 

.7 

.4 

1.1 

.5 

.3 

.4 

.4 .'6 

.5 

.4

1, 710. 4

September 1939

0.44 

.39 

.39 

.44 

.44 

.44 

.49 

.49 

.49 

.49 

.54 

.93 

1.1 

.83 

.74 

.69 

.69 

.64 

.64 

.64 

.64 

.64 

.64 

.59 

.64 

.64 

.64 

.64 

.74 

.74

.........

0.004 

.003 

.003 

.004 

.004 

.002 

.003 

.003 

.003 

.003 

.006 

.3 

.5 

.04 

.05 

.05 

.05 

.04 

.05 

.05 

.05 

.05 

.04 

.04 

.04 

.04 

.1 

.03 

.03 

.03

1.618

May 1939

Discharge 

(secondfeet)

2.8 

2.6 

2.5 

2.4 

2.4 

2.3 

2.2 

2.3 

2.3 

2.2 

2.1 

2.0 

1.8 

1.7 

1.7 

1.7 

1.7 

1.6 

1.6 

1.6 

1.6 

1.6 

1.7 

1.5 

1.5 

1.3 

1.3 

1.2 

1.2 

1.1 

1.1

Sediment 

loads 

(tons)

0.2 

.3 

.1 

.3 

.2 

.3 

.08 

.7 

.08 

.1 

.1 

.07 

.05 

.03 

.02 

.03 

.03 

.02 

.04 

.05 

.04 

.07 

.04 

.03 

.03 

.01 

.04 

.03 

.04 

.07 

.03

3.23

October 1939

0.90 

.90 

.96 

.90 

.83 

1.1 

.83 

.77 

.77 

.71 

.77 

.77 

.77 

.77 

.77 

.77 

.77 

.77 

.77 

.77 

.77 

.77 

.83 

.83 

.90 

.90 

.90 

.90 

.90 

.90 

.90

.........

0.06 

.06 

.05 

.2 

.04 

.06 

.04 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

,02 

.01 

.01 

.01 

.01 

.008 

.008 

.008 

.009 

.009 

.01 

.02 

.02 

.02 

.02 

.02 

.02

0.882
DAILY DISCHARGE AND SEDIMENT LOADS " 

XJROUSE CREEK NEAR ARROW ROCK, IDAHO Continued

91

Day

1_... _ .... 

2.:- .. 

0

J::::::::::::::±:::

S _ 

6.-- - 

7. . ______ _

8- 

9 

10.- 

11 

12 . ... .....

13-. 

14... - 

15.- * 

16.. i

17- 

18- 

19 

20- 

21 - -

22- 

23 

24 

25. 

26 

27- 

28 

29. 

30 

31- 

Total 

1_ 

2, _ . - . 

9. ............. ......

4.-. ...... .... 

5.... __ . _ ------

6 T -

7-. 

8 

9.- 

10- 

11.. - 

19

13.'. 

14 

15.1. .

16 

17 _ -

18- 

19- 

20.L 

21- 

22., 

23.- - ....

24 _ - ....

25..., .

26...?... .........

27__- T 

28.. i..

29. 

30-. . 

31... ........

Total..........

November 1939

Discharge 

(second- 

, feet)

0.96 

.96 

.90 

.90 

.90 

.90 

.90 

.90 

.83 

.77 

.83 

.83 

.83 

.90 

.90 

.90 

.90 

.83 

.90 

.90 

.90 

.90 

.90 

.90 

,.96 

.96 

.96 

.96 

.90 

.90

Sediment 

loads 

(tons)

0.03 

.03 

.03 

.03 

.03 

-.03 

.02 

.02 

.02 

.02 

.02 

.009 

.009 

.01 

.01 

.007 

.007 

.007 

.01 

.01 

.01 

.01 

.007 

.007 

.008 

.008 

.008 

.008 

.01 

.01

0.445

March 1940

'30 

26 

19 

16 

15 

14 

13 

13 

13 

12 

10 

9.1 

8.4 

8.0 

8.0 

8.2 

8.0 

7.7 

7.5 

7.3 

7.1 

7.0 

6.8 

6.8 

7.7 

9.8 

9.8 

9.1 

8.9 

9.8 

16

-- :- 

2,950 

1,840 

-868 

814 

412 

172 , 253 

282 

143 

171 

37 

21 

27 

27 

81 

14 

15 

2.8 

1.5 

1.3 

1.5 

10 

3.4 

11 

22 

72 

91 

43 

44 

73 

564

9,067.5

December 1939

Discharge 

(secondfeet)

0.90 

.96 

.90 

.90 

.90 

1.2 

1.0 

1.0 

1.4 

1.2 

1.5 

1.2 

1.0 

1.0 

1.1 

1.2 

1.4 

1.2 

1.1 

1.2 

1.1 

1.0 

1.0 

.96 

. .59 

.83 

.96 

.96 

1.0 

1.2 

1.6

Sediment 

loads 

(tons)

0.01 

.02 

.01 

.01 

.07 

.4 

.01 

.01 

.05 

.02 

.03 

.02 

.3 

.04 

.03 

.04 

.02 

.02 

.02 

.03 

.03 

.03 

.02 

.02 

.01 

.02 

.02 

.P3 

.03 

.04 

.05

1.46

April 1940

19 

18 

18 

17 

17 

15 

14 

.14 14 ^ 

12 

11 

10 

10 

9.5 

9.1 

8.4 

7.8 

7.5 

7.3 

7.1 

6.8 

6.4 

6.1 

6.0 

6.1 

6.1 

6.4 

6.2 

6.0 

6.0

r

558 

631 

551 

553 

480 

293 

223 

102 

39 

43 

93 

23 

44 

21 

7.5 

5.9 

1.8 

16 

9.2 

5.9 

3.6 

2.6 

.8 

.7 

1.8 

1.3 

2.8 

8.5 

1.7 

1.4

3, 725. 5

January 1940

Discharge 

(secondfeet)

2.1 

3.8 

4.4 

3.6 

2.9 

2.0 

1.7 

1.8 

2.6 

2.6 

2.1 

1.8 

1.5 

1.6 

1.4 

1.4 

1.4 

1.2 

1.2 

1.3 

1.2 

1.2 

1.2 

1.2 

1.2 

2.0 

2.2 

1.9 

1.8 

1.8 

1.8

Sediment 

loads 

(tons)

0.1 

6.4 

.9 

.7 

.09 

.3 

.1 

.01 

.2 

.1 

.5 

.04 

.02 

' .2 .-1 

.06 

,05 

.05 

.05 

.05 

.02 

.02 

.02 

.01 

.01 

1.6 

1.0 

.1 

.08 

.08 

.08

13.04

May 1940

6.0 

5.4 

4.8 

4.5 

4.0 

3.7 

3.5 

3.3 

3.1 

3.0 

2.9 

. 2.8 

2.7 

2.6 

2.6 

2.4 

2.3 

2.2 

2.2 

£1 

2.0 

2.0 

2.0 

1.9 

1.9 

1.9 

1.8 

1.8 

1.8 

1.6 

1.4

 

1.1 

.4

.4 

.2 

.1 

.4 

.1 

.07 

.08 

.09 

.07 

.06 

.05 

.05 

.05 

.08 

.04 

.6 

.03 

.03 

.03 

.03 

.03 

.03 

.03 

.03 

.2 

.2 

.2 

.04 

.03

4.g5

February 1910

Discharge 

(secondfeet)

1.7 

1.7 

3.4 

3.6 

3.2 

6.3 

5.6 

4.8 

4.8 

6.2 

5.6 

4.9 

5.2 

5.4 

4.6 

3.7 

4.0 

3.8 

3.5 

3.2 

3.5 

3.8 

4.0 

. 4.0 

' 7.2 

12 

22 36 ' 

39

Sediment 

loads 

(tons)

0.07 

.09 

1.8 

8.3 

1.4 

49 

7.7 

10 

7.9 

76 

37 

11 

30 

63 

16 

4.9 4.6 ' 

9.8 

6.2 

6.0 

8.2 

2.5 

6.8 

4.5 

68 

272 

900 

2,920 

2,560

7,092.76

June 1940

1.4 

'1.4 

1.3 

1.6 

1.4 

1.2 

1.4 

1.3 

1.2 

1.2 

1.0 

.90 

.83 

.77 

.«71 

v .71 

.71 

.65 

.59 

.54 

.54 

.54 

.48 

.48 

.48 

.42 

.38 

.38 

'.38 

.42

 

0.03 

.03 

.03

.04 :04

.03 

.03 

.03 

.03 

.02 

.03 

.02 

.02 

.01 

.01 

.01 

.01 

.005 

.005 

.004 

.004 

.004 

.004 

.004 

.004 

.004 

.003 

.003 

.003 

.01

0.47T

758529 4£
92 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

MOORE CREEK ABOVE GRANITE CREEK NEAR IDAHO CITY, IDAHO

Discharge and suspended sediment loads, January 1989 to June 1940

Day

1.. ... -

2

3 ... .-...

4

5 .

6 

7 

8 __ ....

» 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24............

25 

26-; 

27 

28 ...

29 

30 

31 

Total. .

Day 

1 ... .

2 .... .

3 

4 

6 ...

6 

7 .

8 .. _ ....

». 

10 

11 

12 

13 

14 ...

15.. _ .......

16 

17 

18 

19 .

20 

21 

22 _ .........

23 .

24- 

25 

26 _ ......

27 

28 

29 

30 

31 

Total. .

January 1939

Discharge 

(secondfeet)

10 

11

8.6 

11 

11 

12 

12 

12 

12 

11 

11 

9.4

Sediment 

loads 

(tons)

0.05 

.09 

.02 

.03 

.2 

.5 

.3 

.5 

.2 

.2 

.2 

.05

2.34

June 1939

12 

11 

10 

13 

9.4 

11 

27 

25 

25 

23 

22 

21 

20 

20 

22 

25 

22 

22 

23 

22 

20 

18 

18 

17 

17 

 15 

15 

11 

7.2 

6.9

........

1.0 

.7 

1.0 

1.4 

.6 

1.1 

2.3 

1.3 

1.1 

.9 

.9 

.7 

.6 

.5 

.9 

1.1 

.9 

.4 

1.2 

.7 

.9 

.6 

.3 

.3 

.2 

.3 

.4 

.3 

.3 

.2

23.1

February 1939

Dipcharge 

(secondfeet)

9.0 

9.0 

10 

. 10 

11 

11 

11 

11 

9.4 

12 

11 

11 

11 

11 

11 

11 

10 

11 

11 

10 

11 

11 

11 

11 

11 

11 

11 

11

Sediment 

loads 

'(tons)

0.3 

.1 

.2 

.2 

.4 

.2 

.7 

.7 

.9 

1.1 

.9 

.6 

.6 

.5 

.2 

.1 

.3 

.2 

.4 

.4 

.2 

.3 

.3 

.4 

.2 

1.0 

.5 

.1

12.0

July 1939

6.9 

6.9 

7.6 

 13 

15 

13 

11 

10 

9.7 

9.7 

9.7 

8.6 

7.6 

7.2 

7.2 

7.2 

7.2 

6.9 

6.9 

6.6 

5.6 

5.6 

5.4 

5.4 

5.1 

5.1 

4.5 

4.8 

4.8 

4.8 

4.8

........

0.1 

.2 

.08 

1.6 

1.5 

.6 

.4 

.2 

.8 

.3 

.8 

.2 

.1 

.2 

.2 

.1 

.1 

.1 

.2 

.1 

.2 

.1 

.1 

.1 

.4 

.03 

.01 

.08 

.2 

.04 

.05

9.19

March 1939

Di^

charge 

(secondfeet)

11 

11 

11 

11 

12 

11 

11 

11 

11 

12 

13 

14 

15 

14 

14 

17 

27 

43 

63 

83 

95 

110 

127 

146 

155 

149 

139 

132 

125 

130 

132

Sediment 

loads 

(tons)

0.2 

.3 

.2 

.3 

1.0 

.2 

.8 

.1 

.4 

.2 

.1 

.3 

1.6 

1.3 

1.1 

1.8 

5.9 

33 

91 

132 

250 

348 

336 

394 

416 

370 

62 

109 

64 

40 

65

2, 725. 8

August 1939

4.8 

4*8 

4.5 

4.5 

4.8 

4.8 

4.8 

4.5 

4.5 

4.5 

4.2 

4.2 

4.2 

4.0 

2.4 

2.4 

2.1 

2.1 

2.1 

2.1 

2.4 

' 2.6 

2.6 

2.8 

3.4 

3.7 

3.7 

3.4 

, 2.6 

2.6 

2.6

........

0.05 

.08 

.09 

.1 

.08 

.04 

.06 

.06 

.07 

.07 

.08 

.09 

.2 

.1 

.09 

.06 

.08 

.04 

.04 

.05 

.09 

.3 

.06 

.1 

.1 

.2 

.07 

.05 

.04 

.06 

.06

2.66

April 193*9

Discharge 

(secondfeet)

135 

146 

157 

164 

143 

123 

114 

114 

110 

99 

96 

95 

87 

86 

90 

92 

98 

110 

123 

131 

141 

148 

146 

132 

110 

101 

102 

122 

150 

163

_,_. __

Sediment 

loads 

(tons)

112

107 

148 

139 

66 

39 

40 

36 

26 

18 

17 

13 

12 

16 

14 

11 

24 

44 

48 

46 

59 

69 

73 

45 

26 

20 

25 

42 

100 

101

1,536

September 1939

2.6 

2.6 

2.8 

2.6 

2.8 

2.8 

2.8 

2.8 

2.4 

2.1 

2.4 

5.6 

9.4 

5.6 

4.2 

3.4 

3.0 

3.9 

6.9 

6.4 

2.4 

2.1 

2.4 

2.4 

2.6 

2.6 

2.6 

2.4 

2.6 

2.8

........

0.1 

.08 

.8 

.04 

.06 

.06 

.05 

.05 

.03 

.03 

.02 

2.9 

2.7 

.5 

.09 

.04 

.03 

.09 

1.2 

.4 

.02 

..01 

.006 

.01 

.02 ' 

.03 

.1 

.03 

.02 

.05

9.566

May 1939

Discharge ' 

vsecondfeet)

153 

148 

148 

/ 146 

136 

122 

105 

92 

84 

84 

97 

98 

87 

67 

78 

71 

53 

54 

44 

35 

32 

29 

26 

23 

20 

19 

17 

16 

 16 

16 

15

Sediment 

loads 

(tons)

71 

67 

55 

57 -

40 

, 27 

1 18 

12 

13 

166 

51 

36 

25 

14 

3.0 

20 

8.9 

9.8 

4.6 

3.1 

4.5 

1.6 

1.3 

1.6 

1.1 

1.8 

1.1 

1.4 

1.3 

1.3 1.2"

719.6

October 1939

3.2 

5.1

5.6 

6.2 

7.2 

11 

5.9 

5.4 

5.6 

6.2 

2.8 

2.6 

2.6 

2.8 

3.2 

3.7 

4.0 

3.4 

3.0 

2.6 

2.6 

2.6 

2.6 

2.6 

3.0 

2.8 

2.6 

3.2 

3.2 

2.8 

2.8

........

0.06 

.3 

.1 

.1 

.4 

1.2 

.09 

.04 

.03 

.08 

.08 

.03 

.06 

.05 

.04 

.04 

.04 

.04 

.008 

.04 j 

.01 

.06 

.03 

.02 

.03 

,06 

.01 

.04 

.03 

.07 

.03

3.218
DAILT DISCHARGE AND SEDIMENT LOADS 93 

MOORE CREEK ABOVE GRANITE CREEK NEAR IDAHO CITY, IDAHO-Continaed

Day

I..... ...............

2

4- 

5--- 

6 -

7 --: < ...

8-.-- -----

9-..- ... -- ....

10--. -

11

19

13..., -------

14-.- 

16-- 

16--. --------

17 

18 

19-- 

20-- 

21 

22 

23.. 

24--- -------

OK

9fi

27. 

28 

29 .

30.-.----. -.-

01

Total 

1. ......

2

3.. .... 

4_ 

5. 

6.--- -------

7 

8. 

9 .

10 

11 

12 

13- 

14., 

16. 

16...- - ... . - --

17..-.- -. .

18 

19. 

20- 

21 

22 

23- .

24.- 

25 

26 

27 

28 .

29.. 

30 ......

31 

, Total. - -

November 1939

Discharj^ (second- ' 

feet) '

2.8 

2.6 

2.6 

2.6 

2.4 

2.4 

2.6 

2.6 

5.6 

7.6 

7.6 

7.6 

7.6 

7.2 

7.2 

7.2 

7.2 

7.1 

7.3 

7.1 

7.2 

7.6 

7.6 

7.6 

7.6 

7.6 

7.6 

7.6 

7.6 

7.6

Sediment 

loads 

(tons)

0.05 

 .02 

.02 

.01 

.01 

.01 

.01 

.01 

1.2 

1.3 

.3 

.5 

.9 

.2 

.3 

.2 

.08 

.6 

.6 

.3 

.5 

.1 

.04 

.08 

.4 

.2 

.08 

.1 

.06 

.06

8.24

March 1940

62 

53 

46 

43 

40 

37 

36 

62 

60 

53 

46 

40 

36 

34 

35 

38 

42 

48 

52 

58 

64 

72 

80 

86 

147 

172 

218 

163 

123 

117 

168

11 

7.3 

4.3 

4.1 

2.3 

2.7 

4.8 

18 

8.4 

4.3 

2.2 

3. 6 

1.9 

1.8 

.9 

2.4 

3.5 

4.9 

9.1 

11 

14 

27 

42 

51 

605 . 

406 

884 

235 

68 

67 

22$

2, 735. 5

December 1939

Discharge 

(secondfeet)

7.6 

7.6 

7.6 

7.6 

6.9 

8.3 

7.6 

8.0 

14 

- 14 

14 

10 

9.7 

9.4' 

10 

17 

23 

 15 

12 

12 

11 

7.1 

9.7 

9.4 

6.0 

8.0 

9.7 

8.6 

10 

11 

12

Sediment 

loads 

(tons)

0.1 

.2 

.08 

.3 

.1 

.2 

.08 

.1 

2.3 

.5 

.9 

.3 

.4 

.2 

.2 

.7 

2.7 

.5 

.6 

.5 

.5 

.2 

.1 

.2 

.05 

.2 

.4 

.09 

.1 

.3 

.4

13.5

April 1940

170 

144 

123 

110 

110 

99 

94ai

103 

100 

99 

105 

119 

136 

127 

110 

103 

109 

119 

119 

100 

93 

89 

85 

84 

91 

119 

86 

74 

69

160 

86 

46 

32 

30 

25 

24 

28 

41 

30 

28 

10-1 

204 

256 

95 

46 

31 

38 

47 

59 

32 

28 

20 

18 

31 

39 

230 

306 

190 

59

2,360

January 1940

Discharge 

(secondfeet)

17 

32 

29 

23 

19 

12 

13 

16 

16 

14 

11 

13 

10 

12 

10 

11 

12 

11 

9.0 

11 

10 

9.7 

10 

10 

9.7 

11 

11 

10 

11 

11 

11

Sediment 

loads 

(ton?)

0.7 

9.3 

1.2 

.4 

.2 

.4 

.3 

1.7 

.4 

.7 

.4 

..2 

.1 

.1 

.05 

.09 

.03 

.2 

.1 

.1 

.4 

.08 

.2 

.05 

.03 

.2 

.3 

.3 

.1 

.6 

.2

19.13

May 1940

67 

72 

83 

86 

78 

74 

74 

76 

84 

99 

116 

123 

119 

108 

97 

90 

86 

82 

80 

78 

77 

75 

74 

74 

74 

72 

66 

61 

59 

56 

54

37 

61 

45 

20 

23 

14 

18 

M 

42 

55 

112 

. 127 

73 

48 

28 

24 

29 

22 

13 

8.2 

22 

,.15 Ms

12 

12 

13

8.4 

4.4 

6.7 

5.6 

5.5

927.8

February 1940

Discharge 

(sccond- 

' feet)

11 

11

12 

13 

12 

17 

17 

15 

14 

20 

18 

14 

16 "16 

14 

16 

13 

13 

11 

10 

12 

12 

13 

12 

15 

25 

53 

87 

88

Sediment 

loads 

(tons)

i 0.05 

.3 

.1 

.2 

.2 

1.7 

.3 

.3 

.3 

1.0 

.2 

.6 

1.9 

.3 

.1 

1.3 

.8 

.2 

.4 

.5 

.3 

.06 

.04 

.03 

.08 

1.6 

27 

76 

54

169'. 86

June 1940

52 

48 

42 

40 

36 

33 

31 

28 

24 

23 

22 

' 18 

16 

12 

12 

8.5 

6.6 

6.0 

4.1 

4.7 

2.8 

2.8 

2.8 

2.3 

2.3 

2.0 

2.0 

2.0 

1.8 

2.0

5.2 

2.9 

4.8 

1.6 

1,7 

2.0 

1.0 

1.4 

.6 

.6 

1.0 

.6 

.7 

2.3 

1.8 

.3 

.2 

.4 

.2 

.1 

.1 

.04 

.04 

.05 

.03 

.03 

.02 

.03. 

.01 

.02

\

29. er
94 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

GOLD HILL PLACER DIVERSION FROM MOORE CREEK NEAR IDAHO CITY, IDAHO

Discharge, in 'second-feet, April 1989 to June 1940

Day

I...... _

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 

1 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 

April 

1939

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

.5I.JK

2.0

2.0

2.5

4.0

6.1

3.7

May 

1939

0.1

0

0

0

1.0

2.8

6.3

10

14

11

0

0

.7

17

.2

9.9

25

19

29

29

28

27

27

27

28

28

29

32

32

32

32

December 1939

June 

1939

31

31

30

. 24

29

25

3.3

4.6

5.0

4.9

4.5

4.2

3.4

3.3

4.0

3.6

3.4

4.2

3.6

3.3

2.7

2.7

2.5

2.5

3.3

6.8

9.8

8.9

January 

1940

^

July 

1939

9.6

9.6

8.9

6.1

5.9

5.9

5.6

5.2

4.7

4.9

4.7 5'.2

5.7

5.7

5.6

5.2

5.6

5.2

,5-0

5.2

5.7

5.7

5.9

5.6

' 5.6

5.2

5.6

5.2

5.2

4.5

4.9

February 1940

August 

1939

4.»

4.5

'3.8 4.4

3.3

4.2

3.6

3.6

3.8

3.8

3.9

3.3

3.9

4.9

4.9

4.9

5.2

5.2

5.2

19

5.0

4.9

5.2

5.2

5.2

5.2

5.2

5.0

5.0

4.9

4.5

-March 

1940

-

September 1939

4.9

5.2

5.2

5.0

5.0

5.0

4.7

4.5

5.2

5.2

5.0

6.3

6.5

5.9

 5.9

5.9

5.9

3.7

0

.9

5.2

5.6

5.7

5.6

5.6

5.7

5.4

5.6

5.6

5.0

April 

1940

0

0

0

0

0 V

0

0

0

0

0

0

0

7.3

18

16

14

. 14

14

14

14

16

19

21

21

21

22

5.9

19

18

20

October* 

1939

4.9

4.9

5.2

5.2

4.7

4.9

4.7

3.9

3.4

2.6

6.3

6.3

6.1

6.3

6.1

5.9

5.9

6.1

-5.4

5.9

6.1

6.1

6.3

5.9

6.7

6.3

6.3

7.1

6.9

6.7

6.3

May 

1940

21

21

21

20

21

21

21

22

23

24

25

22

22

22

25

23

22

23

25

25

25

26

26

25

25

25

25

25

26

26

26

November 1939

6.3

6.3

 6.3

6.1

5.9

5.9

6.3

6.1

3.3

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

June 

1940

25

26

27

27

26

27

26

26

26

26

26

27

28

27

25

27

' 27

25

26

23

21

22

22

21

20

18

18

1 18

17

16

NOTE. No flow December 1939 to March 1940.
DAILY DISCHARGE AND SEDIMENT LOADS 95

MOORE CREEK ABOVE THORN CREEK NEAR IDAHO CITY, IDAHO

Discharge and suspended sediment loads, January 1939 to June 1940

Day

1 ___

2

3, -

4, . 

6. 

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 

Total- .

1 -. .

2 __ . __ ,--

3 _ 

4

5 .

6 

7

8 .

9 

10 

11 

12 

13

14 

15. 

16

17 

18 ,-

19 

20 

21 

22. 

23 

24... .........

26 

26 

27

28 

29 

30 , 

31 

Total..

January 1939

i 

Discharge 

(secondfeet)

28 

27 

27 

25

Sediment 

loads 

(tons)

33 

26 

23

27

109

June 1939

63 

48 

37 

50 

56 

58 

52 

' 50 

52 

52 

49 

44 

40 

38 

38 

42 

48 

46 

46 

46 

45 

39 

37 

34 

32 

30 

38 

28 

27 

26

91 

101 

85 

129 

93 

59 

53 

82

go

106 

123 

213 

69 

56 

45 

44 

41 

36 

44 

69 

70 

66 

88 

91 

77 

61 5-1 

' 40 

34 

30

2,237

February 1939

Discharge 

(secondfeet)

22 

22 

25 

28 

29 

29 

28 

28 

26 

26 

25 

25 

25 

25 

26 

23 

25 

25 

25 

25 

25 

25 

25 

25 

26 

25 

25 

28

Sediment 

loads 

(tons)

20 

19 

23 

26 

30 

33 

35 

33 

33 

. 33 

36 

43 

45 

45 

49 

45 

55 

72 

61 

46 

57 

59 

53 

68 

63 

58 

63 

68

1, 271

July 1939

25 

23 

22 

22 

24 

29 

27 

25 

22 

21 

19 

19 

18 

17 

16 

16 

15 

14 

14 

13 

13 

13 

12 

12 

11 

11 

11 

11 

11 

10 

10

.........

34 

32 

32 

31 

36 

30 

19 

21 

24 

26 

29 

30 

29 

28 

29 

32 

29 

29 

26 

23 

21 

18 16 ' 

13 

12 

12 

12 

12 

11 

10 

9.6

715.6

March 1939

Discharge 

(secondfeet)

31 

30 

30 

30 

29 

28 

27 

27 

28 

29 

33. 

36 

41 

42 

39 

40 

60 

92 

138 

. 189 

213 

252 

. 290 

318 

848 

354 

331 

324 

297 

302 

306

Sediment 

loads 

(tons)

67 

. 84 

71 

68 

61 

63 

76 

71 

95 

81 

76 

70 

96 

99 

78 

79 

140 

206 

291 

303 

359 

366 

332 

346 

410 

349 

225 

225 

171 

174 

195

5,327

August 1939

10 

10 

9.7 

9.1 

9.1 

8.6 

8.1 

8.1 

8.1 

7.7 

7.7 

7.2 

6.7 

6.7 

6.7 

. 6.7 

6.4 

6.0 

6.0 

5.7 

5.3 

5.0 

5.0 

5.0 

5.0 

5.0 

5.0 

5.0 

5.0 

5.0 

5.0

9.4

9.4 

8.8 

9.2 

8.9 

8.4 

7.4 

7.1 

7.6 

7.3 

7.2 

6.8 

6.8 

6.8 

6.7 

6.8 

6.5 

6.3 

6.4 

5.9 

5.7 

5.3 

5.6 

5.7 

5.4 

'5.7 

5.7 

5.6 

5.7 

5.6 

5.5

211.2

April 1939

Discharge 

(secondfeet)

318 

336 

' 348 

371 

.336 

285 

259 

254 

250 

229 

222 

218 

200 

189 

193 

196 

196 

207 

222 

234 

245 

256 

259 

250 

218 

196 

187 

196 

229 

266

Sediment 

loads 

(tons)

'235 

237 

235 

269 

163 

129 

126 

109 

106 

101 

111 

97 

109 

100 

95 

79 

79 

112 

137 

140 

167 

137 

144 

109 

91 

69 

40 

< 38 

98 

124

3,786

September 1939

5.3

s. a

5.7 

5.7 

5.7 

6.0 

6.0 

6.4 

6.4 

6.4 

6.4 

7.7 

9.1 

10 

13 

14 

15 

14 

14 

13 

12 

11 

11 

11 

11 

11 

11 

11 

10 

10

........

5.7 

5.8 

6.7 

6. .5 

6.7 

6.9 

7.8 

8:3 

I 8.9 

1 9.4 

9.0 

11 

13 

15 

20 

22 

19 

14 

13 

9.4 

716 

6.9 

8.1 

9.4 

11 

11 

12 

11 

10 

9.4

314.5

May 1939

Discharge 

(second- 

. feet)

261 

243 

 238 

234 

227 

204 

182 

163 

155 

151 

151 

144 

128 

125 

125 

126 

112 

110 

107 

103 

94 

81 

' 86 

63 

70 

80 

72 

68 

69 

74 

68

Sediment 

loads 

(tons)

113 

120 

128 

108 

99 

81 

106 

104 

93 

135 

144 

120 

135 137- 

137 

142 

152 

186 

284 

309 

175 

127 

153 

115 

183 

142 

130 

133 

155 

135 

108

4,389

October 1939

11 

11 

11 

11 

12 

14 

14 

16 

17 

17 

16 

15 

15 

15 

14 

14 

14 

13 

14 

- 14 

.15 

15 

15 

15 

15 

18 

19 

16 

16 

17 

32

.. .-. 

10 

11 11 ' 

11 

12 

14 

13 

16 

. 17 

18 

16 

15 

15 

14 

13 

12 

12 

12 

 13 

13 

14 

14 

13 

13 

14 

17 

20 

18 

19 

22 

42

474
96 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

MOORE CREEK ABOVE THORN CREEK NEAR IDAHO CITY, IDAHO Continued

1 

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..... __ ..........

Total..........

1.. ... ....... ...

2.. .. ................

3.. ... ...... .... --

,4.. ...... -

5.. ... .... ... -.

6.-. 

7.. ..... ... -

8-.. ... -.

9.. ... .... 

10. 

11 

12.. . ................

13 

14 

15 

16 

17 -

18- 

19. 

20 

21.. 

99

23- 

24. .-

25... -.* .

26--- 

27- 

28 

29- 

30.. -

q-i

Total-. .......

November 1939

Discharge 

(secondfeet)

35 

23 

19 

17 

16 

15 

15 

16 

15 

14 

13 

13 

14 

15 

15 

15 

16 

21 

18 

17 

17 

18 

22 

23 

22 

28 

22 

19 

20 

19

Sediment 

loads 

(tons)

64 

33 

25 

23 

23 '23 

25 

26 

26 

26 

21 

20 

21 

23 

.25 

44 

33 

67 

37 

33 

44 

41 

71 

64 

57 

83 

59 

46 

65 

55

1,203

March 1940

213 

174 

153 

138 

126 

114 

108 

155 

178 

159 

136 

114 

105 

103 

100 

103 

112 

117 

130 

136 

146 

157 

170 

182 

250 

381 

629. 

448 

361 

312 

405

223 

159 

131 

206 

139 

141 

110 

244 

161 

146 

117 

98 

86 

99 

97 

102 

121 

158 

177 

113 

' 58 

110 

92 

136 

752 

1,460 

4,550 

655 

394 

493 

894

12,422

December 1939

Discharge 

(secondfeet)

17 

20 

19 

16 

16 

18 

18 

19 

22 

32 

35 

33 

28 

27 

29 

32 

46 

41 '35 

32 

30 

25 

21 

21 

19 

18 

19 

e 19 

22 

22 

27

Sediment 

, loads 

" (tons)

45 

55 

60 

49 

38 

35 

35 

50 

62 

97 

78 

80 

70 

70 

98 

83 

112 

67 

67 

74 

61 

46 

41 

45 

40 

29 

22 

27 

52 

54 

60

I SO 9

April 1940

448 

402 

345 

291 

302 

271 

266 

244 

259 

249 

237 

230 

247 

284 

299 

261 

247 

244 

251 

259 

232 

212 

199 

192 

192 

203 

242 

214 

203 

186

821 

507 

465 

328 

373 

283 

305 

163 

233 

208 

136 

137 

173 

217 

253 

201 

215 

219 

268 

278 

199 

234 

226 

328 

365 

364 

340 

254 

232 

200

8,525

January 1940

Discharge 

(secondfeet)

35 

52 

66 

61 

50 

38 

33 

25 

34 

38 

34 

28 

25 

24 

23 

24 

25 

25 

23 

23 

23 

23 

23 

23 

23 

25 

29 

30 

28 

27 

26

Sediment 

loads 

(tons)

81 

153 

168 

122 

78 

59 

66 

54 

98 

94 

94 

76 

63 

52 

74 

79 

74 

59 

55 

67 

80 

78 

73 

53 

49 

62 

96 

100 

82 

92 

88

2,519

May 1940

182 

167 

188 

194 

182 

169 

167 

165 

173 

188 

« 214 

228 

230 

219 

203 

188 

177 

169 

161 

161 

155 

147 

145 

143 

143 

143 

134 

127 

123 

119 

112

476 

335 

383 

386 

313 

209 

317 

283 

295 

321 

285 

316 

347 

293 

277 

308 

249 

266 

218 

205 

349 

243 

211 

170 

137 

178 

194 

178 

173 

167 

 166'

8,248

February 1940

Discharge 

(secondfeet)

25 

24 

28 

32 

33 

40 

52 

46 

41 

51 

- 62 

50 

42 

46 

42 

35 

36 

38 

32 

28 

27 

34 

36 

36 

37 

52 

136 

263 

287

Sediment 

loads 

 (tons)

67 

62 

82 

78 

77 

78 

103 

72 

69 

110 

114 

80 

60 

65 

82 

63 

80 

70 

59 

50 

45 

63 

54 

64 

65 

108 

 606 

717 

519

3,762

Jane 1940

109 

104 

99 

97 

99 

87 

83 

80 

70 

69 

65 

63 

59 

56 

55 

53 

48 

44 

42 

32 

36 

3ff 

36 

46 

40 

31 

32 

29 

29 

24

132 

113 

129 

123 

266 

189 

240 

152 

152 

114 

99 

122 

107 

91 

95 

99 

119 

105 

80 

51 

67 

72 

70 

150 

143 

80 

87 

91 

102 

86

3,526
DAILY DISCHARGE AND SEDIMENT LOADS 97

GRANITE CREEK NEAR IDAHO CITY, IDAHO

Discharge and total sediment loads, January 1989 to June 1940

Day

1 .....

2

3.. -.

4 . ....

5 __ .._ .

6 .... ...

7- 

8 _

9.... .........

10 

11 

12-. ,......

13 

14 

15 

16. .... _ 

17 

18 

19 

20-- 

21.. .......

22 ...

23 ......... atji 

25 .........

26 

27 .......

28 .......

29 .......

30 

31 

Total ..

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 

Total . .

January 1939

Discharge 

(secondfeet)

0.72 

.74

.76 

.76 

.76 

.64 

.64 

.64 

.64 

.64 

.68 

.76 

.72 

.72

.76

.72

Sediment 

loads 

(tons)

........

0.01 

.01 

.006 

.04 

.02 

.03 

.01 

.02 

.02 

.04 

.02 

.004

.01

.02

0.260

June 1939

0.88 

.90 

.94 

.82 

.84 

.92 

.88 

.92 

1.0 

.86 

.81 

.82 

.77 

.74 

.90 

1.0 

.92 

.92 

1.0 

 .88 

.82 

.77 

.68 

.64 

.60 

.56 

.64 

.64 

.60 

.60

.........

0.04 

.04 

.06 

.05 

.03 

.02 

.03 

.04 

.03 

.02 

.02 

.02 

.02 

.02 

.1 

.05 

.06 

.02 

.05 . 

.02 

.01 

.01 

.007 

.009 

.01 

, .006 

 .01 

.01 

.01 

.01

0.832

February 1939

Discharge 

(secondfeet)

0.75 

.80 

.80 

.80 

.80 

.80 

.80 

.84 

.80 

.85 

.80 

.84 

.80 

.84 

.96 

.72 

.88 

.80 

.80 

-.80 

.75 

.84 

.88 

.88 

.88 

.88 

.92 

.88

Sediment 

loads 

(tons)

0.03 

.009 

.02 

.03 

.1 

.04 

.05 

.2 

.2 

.04 

.04 

.1 

.06 

.02 

.06 

.06 

.02 

.2 

.2 

.09 

.1 

.3 

.2 

.03 

.04 

.04 

.02 

.02

2.319

July 1939

0.56 

.56 

.60 

.72 

.68 

.60 

.56 

.53 

.53 

.49 

.45 

.45 

.42 

.42 

.45 

.45 

.45 

.42 

.42 

.38 

.38 

.42 

.42 

.45 

.42 

.42 

.38 

.42 

.42 

.42 

.38

.... .....

0.01 

.01 

.01 

.03 

.03 

.01 

.03 

.01 

.01 

.01 

.01 

.01 

.01 

.01 

.01 

.009 

.005 

.006 

.01 

.009 

.009 

.01 

.01 

.01 

.01 

.008 

.007 

.008 

.008 

.008 

.007

0.344

March 1939

Discharge 

(secondfeet)

0.88 

.92 

.92 

.88 

.88 

.88 

.88 

.88 

.92 

 1.0 

1.0 

1.1 

1.4 

1.6 

1.3 

1.7 

2.4 

3.0 

3.7 

4.0 

4.6 

5.1 

5.6 

6.3 

6.8 

6.8 

6.7 

6.6 

6.2 

6.2 

6.4

Sediment 

loads 

(tons)

0.05 

.005 

.01 

. .2 

.08 

.04 

.07 

.02 

.02 

.1 

.3 

.1 

.6 

.5 

.06 

2.3 

8.7 

35 

88 

52 

114 

238 

199 

212 

276 

212 

233 

81 . 

118 

124 

64

2, 059. 155

August 1939

0.38 

.38 

.38 

.38 

.38 

.38 

.38 

.38 

.38 

.38 

.38 

.38 

.38 

.35 

.35 

.38 

.38 

.35 

.35 

.35 

.35 

.35 

.35 

.38 

. .38 

.35 

.35 

.35 

.31 

.35 

.31

 

0.007 

.007 

.007 

.007 

.007 

.007 

.007 

.005 

.005 

.005 

.005 

.005 

.005 

.005 

.005 

.005 

.008 

.008 

.008 

.008 

.008 

.005 

.005 

.005 

.005 

.001 

.001 

.001 

.001 

.001 

.001

0.160

April 1939

Discharge 

(secondfeet)

6.6 

6.5 

6.5 

6.6 

5.9 

5.0 

4.6 

4.6 

4.5 

4.2 

3.9 

3.7 

3.4 

3.2 

3.1 

3.0 

2.8 

2.9 

3.1 

3.0 

3.1 

3.1 

3.1 

3.1 

2.8 

2.6 

2.6 

2.6 

3.1 

3.6

Sediment 

loads 

(tons)

108 

87 

147 

165 

73 

30 

14 

56 

19 

10 

10 

13 

4.3 

12 

10 

3.2 

2.9 

2.8 

4.5 

1.8 

3.3 

-1.7 

1.9 

.9 

2.6 

1.7 

.4 

.7 

'3.7 

12

802.4

September 1939

0.35 

.35 

.35 

.35 

.35 

.35 

.35 

.35 

.35 

.31 

.35 

.70 

.80 

.45 

.42 

.38 

.35 

.35 

.35 

.35 

.35 

.35 

.37 

.42 

.44 

.42 

.42 

.44 

.44 

.44

0.001 

.001 

.001 

.001 

.001 

.001 

.005 

.005 

.005 

.004 

.005 

.1 

.1 

.006 

.006 

.005 

.003 

.003 

.003 

.003 

.003 

.005 

.005 

.006 

.006 

.006 

.005 

.005 

.005 

.005

0.310

May 1939

Discharge 

(second- 

 feet)

3.2 

3.1 

3.0 

2.9 

2.7 

2.'5 

2.3 

2.1 

2.1 

2.0 

1.9 

1.8 

1.7 

1.6 

1.5 

1.6 

1.5 

1.4 

1.4 

1.4 

1,3 

1.4 

1.4 

1.3 

1.3 

1.2 

1.2 

1.1 

1.0 

.95 

.94

Sediment 

loads 

(tons)

8.7 

2.8 

2.0 

2.4 

1.7 

6.6 

6.8 

13 

7.3 

2.2 

3.4 

2.7 

2.6 

2.2 

.9 

.7 

.2 

.3 

.1 

.09 

.3 

.2 

.2 

.1 

.1 

.1 

.07 

.05 

.07 

.06 

.03

67.97

October 1939

0.51 

.57 

.53 

.53 

.62 

.80 

.62 

.57 

.53 .53' 

.53 

.53 

.53 

,53 

.53 

.53 

.51 

.55, 

.57 

.59 

.59 

.59 

.57 

.57 

.64 

.62 

.59 

.66 

.62 

.59 

.59

. 0.007 

.008 

.007 

.01 

.02 

.02 

.01 

.003 

.003 

.003 

.003 

, .004 

.004 

.004 

.004 

.004 

.004 

.006 

.006 

.006 

.006 

.006 

.005 

.005 

.005 

.005 

.006 

.007 

.007 

.006 

.006

0.200
98 , DISCHARGE AND SEDIMENT, BOISE RIVER BASIN 

GRANITE*CREEK NEAR IDAHO CITY, IDAHO Continued

Day

1 . .

2.... .............

3_ - .. 

4....................

5... . ... ..---.

6.. ....... .......... .

7...-.. __ .......

8.. .......... ........

9.... .......... ...

lO-i - 

11- 

12...................

13. 

14.. .................

15- 

16 ....

17... .

18.. ...

19. 

20... .

21.. .

22 . __ .... _ . _ ..

23

24.. .................

25 

26 

27 

28... .........

29- 

30. 

31.. 

Total 

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.- ..

Total... 

November 1939

Discharge 

(secondfeet)

- 0.59. 

.62 

.59 

.59 

.57 

.62 

.64 

.62 

.50 

.51 

.66 

.62 

.62 

.59 

.59 

.60 

.50 

.64 

.64 

.66 

.65 

.68 

.66 

.66 

.66 

.70 

.70 

.64 

.66 

.66

Sediment 

loads 

(tons)'

0.006 

.008 

.008 

.008 

.04 

.003 

.004 

.003 

.05 

.02 

.03 

.03 

.03 

 .02 

.02 

.02 

.02 

.03 

.02 

.02 

.02 

, ' .02 

.02 

.01 

.01 

.01 

.01 

.01 

.01 

.01

0.520

March 1940

4.4 

3.7 

3.2 

2.9 

2.6 

2.4 

2.6 

3.5 

3.2 

3.1 

2.8 

2.4 

2.5 

2.5 

2.5 

2.7 

2.9 

2.9 

3.0 

3.1 

3.1 

3.2 

3.4 

3.5 

5.5 

8.7 

12 

8.9 

7.6 

7.2 

9.9

40 

14 

6.4 

4.2 

2.0 

1.9 

2.5 

9.7 

5.0 

8.1 

2.2 

7.7 

3.0 

1.3 

1.9 

, 5.3 

3.5 

4.9 

4.4 

3.7 

8.2 

13 

9.9 

12 

73 

140 

392 

250 

104 

49 

69

1, 251. 8

December 1939

Discharge 

(secondfeet)

0.66 

.66 

.66 

.64 

.64 

.80 

.68 

.75 

1.1 

.92 

1.1 

.82 

.80 

.77 

' .87 

1.0 

1.4 

.92 

-.77 

.90 

.73 

.49 

.74 

.77 

.40 

.70 

.84 

.73 

.75 

.87 

1.0

Sediment 

loads 

(tons)

0.01 

.01 

.01 

.01 

.01 

.02 

.02 

.02 

.01 

.04 

.05 

.04 

.04 

.04 

.2 

.1 

.1 

:2 

.02 

.02 

.02 

.01 

.02 

.3 

.02 

.04 

.05 

.04 

.04 

.08 

.05

1.64

April 1940

11 

9.1 

8.0 

7.3 

7.4 

6.4 

5.9 

5.7 

5.9 

5.4 

5.2 

5.0 

5,2 

5.3 

5.4 

5.0 

4.6 

4.4 

4.2 

4.2 

4.0 

3.8 

3.7 

3.5 

3.5 

4.6 

5.6 

5.0 

4.8 

4.4

79 

33 

48 

18 

8.2 

14 

4.4 

9.3 

7.3 

6.6 

5.3 

2/9 

3.2 

2.6 

2.1 

3.5 

3.9 

.9 

1.0 

2.9 

1.2 

1.2 

.8 

.5 

1.6 

2.3 

2.8 

3.0 

2.2 

.7

272.4

January 1940

Discharge 

(secondfeet)

1.4

1.8 

1.5 

1.3 

1.0 

.59 

. 75 

1.0 

.97 

.92 

.71 

.90 

.70 

.88 

.70 

.77 

.77 .75' 

.73 

.73 

.73 

.73 

.73 

.75 

.77 

.92 

.90 

.82 

.80 

.80 

.75

Sediment 

loads 

(tons)

2.9 

1.5 

.8 

1.4 

.2 

.3 

.4 

.6 

.1 

.05 

.1 

.05 

,.04 

.05 

.1 

.9 

.04 

.02 

.02 

.02 

.01 

.01 

.01 

.01 

.09 

.02 

.1 

.03 

.05 

.5 

.6

11.02

May 1940

. 4.1 

4.0 

4.0 

3.9 

3.6 

3.4 

3.3. 

3.1 

3.0 

3.0 

3.0 

3.0 

3.0 

2.8 

2.6 

2.4 

2.3 

2.2 

2.1 

2.0 

1.9 

1.8 

1.7 

1.6 

1.6 

1.6 

1.5 

1.5 

1.4 

1.3 

1.3

1.5 

1.2 

.6 

.8 

.5 

.3 

.3 

.6 

.6 

.3 

.5 

.3 

.4 

.7 .8 ' 

.2 

.2 

.2 

.2 

.1 

.08 

.07 

.08 

.07 

.1 

.08 

.06 

.09 

.07 

.06 

.04

11.10

February 1940

Discharge 

(secondfeet)

0.70 

.80 

1.0 

1.1 

1.0 

1.5 

1.4 

1.2 

1.2 

1.8 

1.4 

1.1 

1.3 

1.3 

l.'l 

1.1 

1.1 

1.0 

.90 

 8.7 

.95 

1.0 

.97 

.97 

1.4 

2.3 

5.5 

7.3 

6.1

Sediment 

loads 

(tons)

0.2 

.09 

.02 

.1 

.08 

1.2 

.3 

.2 

.3 

1.0 

.6 

.5 

.6 

.4- 

.5 

.5 

.05 

.2 

2.2 

.6 

.08 

.8 

.4 

.2 

1.5 

3.0 

104 

218 

75

412. 62

June 1940

1.3 

1.3 

1.2 

1.4 

1.2 

1.1 

1.1 

1.1 

1.0 

.94 

.90 

.84 

.80 

.77 

..73 

.70 

.68 

.64 

.59 

.59 

.57 

.57 

.55 

.53 

.51 

.49 

' .49 

.47 

.47 

.49

..........

0.04 

.04 

.05 

.07 

.1 

.06 

.06 

.06 

.04 

.04 

.03 

.02 

.02 

.02 

.02 

.02 

.02 

.02 

.01 

.01 

.01 

.009 

.009 

.01 

.01

 .01 

, .01

.01 

.01 

.01

0.848
DAILY DISCHARGE AND SEDIMENT LOADS 99

BANNOCK CREEK NEAR IDAHO CITY, IDAHO

Discharge and total sediment loads, January 19S9 to June 1940

Day

1 -

2

3 

4.. _ ..---...

5 

6

7 . .... ... ..

8.. ...... - --

0... ...... ....

10 11 

12... ... ......

13 . 

14 

IS 

16 

17 

18.. .......

19 

20 

21 .. ,._. 

22 

23 

24 

25 

26. 

27 

28 

29 

30

31 

Total. .

Day

1 . .

2 ...

3 

4 

5 

6 ,....

7.. _ -, 

8 -....

9 

10 

11 

12... ...... ...

IS 

14 

15 -

16 

17 _ . ___ -.

18 

19 

20 

21 

22 

23 

24. _ 

25 

26 

27 . 

28 

29 

30 si 

Total..

January 1930

Discharge 

(secondfeet)

0-68 

.68 

.68 

.68 

.68 

.68 

.61 

.68 

.68 

.68 

.68 

.68 

.68 

.68

.68

.65

Sediment loads" 

(tons)

0.01 

.01 

.01 

.01 

.007 

.009 

.005 

.005 

.004 

.002 

.002 

.002 

.002 

.002

.002

.005

0.087

June 193£

0.03 

.03 

.93 

.93 

.80 

.80 

.89 

.89 

.08 

.85 

.82 

.78 

.74 

.74 

.78 

.85 

.78 

.78 

.85 

.78 

.68 

».68 

.61 

.61 

.58 

.55 

.52 

.52 

.50 

.30

0.09 

.00 

.09 

.00 

.02 

.02 

.02 

.03 

.03 

.03 

.02 

.02 

.02 

.006 

.006 

.007 

.006 

.006 

.007 

.006 

.05 

.05 

.04 

.04 

.005 

.004 

.004 

.004 

.007 

.005

0.823

February 1939

Discharge 

(secondfeet)

0.65 

.68 

.68 

.68 

.68 

.68 

.68 

.68 

.68 

.71 

.71 

.71 

.71 

.71 

.74 

.71 

.74 

.74 

.74 

.71 

.71 

.68 

.68 

.71 

.68 

.68 

.68 

.71

Sediment 

loads 

(tons)

0.01 

.02 

.002 

.002 

.002 

.OC'2 

.002 

.004 

.005 

.002 

.04 

.05 

.06 

.02 

.01 

.02 

.04 

.01 

.01 

.01 

.02 

.02 

.01 

.01 

.02 

.01 

.007 

.03

0.448

July 1939

0.39 

.42 

.42 

.55 

.55 

.50 

.44 

.39 .37- 

.37 

.34 

.32 

.30 

.25 

.25 

.25 

.25 

.23 

.23 

.23 

.19 

.21 

.19 

.19 

.17 

.19 

.19 

.21 

.23 

.21 

.19

O.OC5 

.006 

.006 

.008 

.008 

.007 

.006

. .oor.

.007 

.007 

.006 

.006 

.006 

.008 

.008 

.008 

.008 

.007 

.007 

.002 

.002 

.002 

.002 

.002 

.001 

.005 

.005 

.005 

.006 

.005 

.003

0.171

March 1939

Discharge 

(secondfeet) .

0.70 

.74 

.74 

.74 

. .70 

.71 

.71 

.71 

.71 

.74 

.71 

.78 

.85 

.74 

.74 

.85 

.85 

.93 

1.1 

1.2 

1.3 

1.5 

1.7 

2.0 

2.4 

2.6 

2.8 

2.8 

2.8 

2.9 

3.2

Sediment 

loads 

(tons)

0.02 

.02 

.02 

.008 

.008 

.008 

.008 

.008 

.COS 

.008 

.01 

.01 

.01 

.01 

.01 

.01 

.01 

.01 

.03 

.06 

.06 

.07 

.08 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.2

1.396

August 1939

0.17 

.17 

.17 

.16 

.16 

.16 

.17 

.17 

.16 

.17 

.17 

.16 

.16 

.14 

.16 

.16 

.14 

.14 

.14 

.16 

.14 

.16 

.16 

.17 

.17 

.17 

.17 

.17 

.14 

.16 

.14

.........

0.002 

.002 

.002 

.004 

.004 

.004 

.005 

.002 

.002 

.002 

.002. 

.002 

.002 

.002 

.002 

.002 

.005 

.005 

.005 

.006 

.005 

.001 

 .001 

.001 

.001 

.001 

.001 

.001 

.002 

.003 

.002

0.081

April 1939

Discharge 

(secondfeet)

3.6 

3.9 

4.1 

4.3 

4.1 

3.8 

3.6 

13.7 

3.6 

3.4 

3.1 

3.1 

2.9 

2.8 

2.8 

2.7 

2.7 

2.8 

3.0 

3.0 

3.1 

. 3.2 

3.1 

3.1 

2.8 

2.6 

2.6 

2.6 

2.9 

3.4

Sedi7 

ment 

loads 

(tons)

i 

0.3 

.4 

.6 

.6 

.4 

.2 .2 ' 

.2 

.2 

.3 

.2 

.2 

.2 

.2 

.2 

.2 

.2 

.2 

.2 

.2 

.2 

.2 

.1 

.1 

.08 

.07 

.07 

.1 

.4 

1.0

7.72

September 1939

0.14 

.16 

.17 

.17 

.17 

.17 

.17 

.16 

.17 

.17 

.19 

.46 

.58 

.37 

.30 

.28 

.25 

.23 

.23 

.25 

.25 

.25 

.28 

.28 

.28 

.25 

.23 

.25 

.25 

.25

.........

0.002 

.003 

.001 

.001, 

.001 

.001 

.002 

.002 

.002 

.002 

.002 

.02 

.04 

.004 

.003 

.003 

.003 

.001 

.001 

.001 

.001 

.001 

.002 

.002 

.002> 

.001 

.001 

.001 

.001 

.001

0.108

May 1939

Discharge 

(secondfeet)

3.2 

3.0 

3.0 

2.9 

2.9 

2.7 

2.6 

2.5 

2.3 

2.2 

2.1 

1.9 1.7' 

1.6 

1.6 

1.6 

1.6 

1.5 

1.4 

1.4 

1.3 

1.3 

1.3 1.2 

1.2 

1.1 

1.2 

1.1 

1.0 

1.0 .98'

Sediment 

loads 

(tons)

0.2 

.2 

.2 

.1 

.1 

.05 

..05 

.05 

.2 

.7 

.05 

.07 

.07 

. .3 

.1 

.04 

,05 

.02 

" .03 

.07 

.07 

.07 

.03 

.03 

.03 

.03 

.05 

.05 

.04 

.09 

.09

3.23

October 1939

0.30 

.37 

.34 

.34 

.37 

.55 

.39 

.37 

.34 

.34 

.34 

.34 

.34 

.34 

.34 

.34 

.34 

.34 

.32 

.32 

.32 

.32 

.32 

.34 

.39 

.39 

.39 

.M 

.42 

.39 

.39

 

0.006 

.007 

.006 

.005 

.006 

.009 

.006 

.006 

.001 

.001 

.001 

.001 

' .001 

.001 

.001 

.001 

.001 

.003 

.003 

.003 

.003 

.003 

.003 

.003 

.003 

.003 

.001 

.001 

.001 

.001 

.001

0.092

1 Approximately 4.1 cubic yards of sand removed from weir pool.

2 Approximately 1.1 cubic yards of sand removed from weir pool.
100 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN 

BANNOCK CREEK NEAR IDAHO CITY, IDAHO Continued

Day

1

3.... ...... ...

4

5. . .

6. ........

7

8

9_. 

10-. 

11- 

12 

13. 

14- 

15.- 

16 

17-- - 

19- 

20 

21....- . 

22 

23. 

24. 

25- 

26-.. . 

27_ 

28 

29- 

30- 

31-. 

Total-. _ --..

Day

1 '

2... _ .- .... .

3

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... 

Total.. _ .....

November 1939

Discharge 

(secondfeet)

0.39 

.39 

.39 

.39 

.37 

.39 

.39 

.39 

.32 

.34 

.39 

.39 

.39 

.39 

.37 

.34 

.34 

.37 

.37 

.37 

.37 

.39 

.39 

.42 

.39 

.39 

.39 

.42 

.42 

.44

..........

Sediment 

loads 

(tons)

0.001 

.007 

.007 

.007 

.007 

.001 

.001 

.001 

.002 

.002 

.002 

.002 

.002 

.002 

.005 

.005 

.005 

.005 

.005 

.005 

.002 

.002 

.002 

.002 

.002 

.002 

.003 

.004 

.004 

.004

0.101

March 1940

2.0'

1,7 

1.6 

1.4 

1.3 

1.4 

1.3 

1.9 

1.7 

1.7 

1.6 

1.4 

1.4 

1.4 

1.4 

1.6 

1.6 

1.7 

1.7 

1.8 

2.0 

2.1 

2.3 

2.6 

4.3 

6.7 

11 

7.5 

26.2 

6.4 

7.8

0.05 

.04 

.08 

.03 

.01 

.07 

.04 

.08 

.05 

.03 

.06 

.3 

.2 

.05 

.06 

.1 

.06 

.07 

.06 

.07 

.07 

.1 

.1 

.2 

3.6 

111 

135 

42 

25 

47 

77

442. 58

December 1939

Discharge 

(secondfeet)

0.44 

.44 

.44 

.44 

.42 

.58 

.44 

.52 

.85 

.68 

.85 

.58 

.55 

.55 

.64 

.85 

1.2 

1.1 

.74 

.61 

.52 

.42 

.50 

.47 

.40 

.45 

.50 

.47 

.50 

.58 

.68

..........

Sediment 

loads 

(tons)

0.004 

.004 

.004 

.004 

.004 

.005 

.02 

.03 

.05 

.04 

.05 

.008 

.008 

.008 

.009 

.03 

.07 

.01 

.006 

.005 

« .004 

.004 

.004 

.004 

.003 

.004 

.004 

.004 

.007 

.03 

.05

0.487

April 1940

7. '5 

6.9 

6.0 

5.6 

5.7 

5.3 

5.1 

5.1 

5.1 

4.8 

4.6 

4.8 

5.1 

5.4 

"5.4 

5.3 

5.0 

4.7 

4.8 

5.3 

5.0 

4.7 

4.4 

4.2 

4.2 

4.8 

5.9 

5.6 

5.4 

5.1

81 

46 

30 

14 

14 

8.4 

9.8 

5.7 

8.2 4.2' 

7.-6 

8.2 

5.4 

3.1 

4.8 

2.6 

3.4 

2.4 

3.3 

2.0 

2.1 

1.4 

1.2 

1.2 

1.0 

1.7 

4.4 

1.8 

1.9 

1.5

282.3

January 1940

Discharge 

(secondfeet)

0.82 

1.2 

1.0 

.82 

.71 

.50 

.55 

.68 

.68 

.68 

.61 

.58 

.50 

.55 

.50 

.50 

.50 

.52 

.50 

.50 

.50 

.50 

.50 

.50 

.52 

.61 

.61 

.55 

.55 

.55 

.52

Sediment 

loads 

(tons)

0.1 

.2 

.02 

.01 

.01 

.008 

 .009 

.004 

.004 

.009 

.002 

.002 

.001 

.001 

.008 

.008 

.008 

.006 

' .005 

.005 

.005 

.005 

.005 

.004 

.004 

.005 

.005 

.004 

.004 

.004 

.004

0.469

May 1940

4.8 

4.6 

4.4 

4.4 

4.2 

4.1 

3.7 

3.5 

8.4 

3.4 

3.4 

3.2 

3.1 

3.0 

2.9 

12.8 

2.7 

2.5 

, 2.3 

2.3 

2.1 

2.0 

1.9 

1.7 

1.7 

1.7 

1.6 

1.6 

1.5 

1.4 

1.3

0.9 

1.3 

1.0 

.7 

.8 

.6 

.6 

.4 

.2 

.6 

.2 

.1 

.2 

.6 

.8 

.8 

.2 

.2 

.2 

.07 

.07 

.06 

.09 

.05 

.05 

.09 

.08 

.05 

.03 

.03 

.02

1.059

February 1940

Discharge 

(secondfeet)

0.52 

.52 

.61 

.64 

.61 

.78 

.71 

.61 

.64 

.89 

.71 

.58 

.74 

.71 

.64 

.61 

.61 

.61 

.55 

.52 

.55 

.58 

.61 

.61 

.78 

1.1 

1.9 

2.8 

2.5

..........

Sediment loads " 

(tons)

0.004 

.004 

.005 

.01 

.01 

.04 

.01 

.04 

.04 

.1 

.02 

.03 

.04 

.03 

.02 

.01 

.01 

.01 

.009 

.007 

.008 

.008 

.01 

.002 

.02 

.2 

.4 

.6 

.1

1.797

June 1940

1.3 

1.3

1.2 

1.3 

1.3

1.2 

1.2 

1.1 

1.1 

1.0 

.93 

.85 

.82 

.82 

.78 

.74 

.71 

.68 

.64 

.58 

.61 

.58 

.58 

.55 

.52 

.52 

.50 

.50 

.47 

.50

0.02 

.02 

.02 

.02 

.02 

.04 

.02 

.01 

.01 

.02 

.02 

.02 

.02 

.02 

.01 

.01 

.01 

.01 

.01 

.008 

.008 

.009 

.009 

.009 

.01 

.01 

.01 

.01 

.008 

.008

0.429

1 Approximately 3.9 cubic yards of sand removed from weir pool. 

1 Approximately 3.4 cubic yards of sand removed from weir pool.
DAILY DISCHARGE AND SEDIMENT LOADS 

PINE CREEK NEAR IDAHO CITY, IDA*HO

Discharge and total sediment loads, January 1989 to February 1940

101

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-.... .......

Total. _

Day

I.-------.-...

2. .. .......

3 

4.............

5 ... .....

6 

7 ..........

8 ...

9. ........

10 

11 

19

13 

14 . 

15-- -__-_

16 

17 - ..

18 

19... ......

20 

21 ..

22 ..

23. .

24 .........

25 ....

26 .

27 

28.... ...

29............

30- -...

31- .

Total..

January 1939

Discharge 

(secondfeet)

0.57 

.57 

.57 

.57 

.57 

.57 

.54 

.54 

.54 

.57 

.61 

.61 

.61 

.61

.65

.60

Sediment 

loads 

(tons)

1

0.02 

.008 

.008 

.005 

.005 

.07 

.01 

.5 

.03 

.05 

.01 

.08 

.03 

.02

.01

.02

0.876

June 1939

0.27 

.31 

.27 

.27 

.31 

.31 

.31 

.31 

.31. 

.27 

.31 

.31 

.31 

.'31 

.35 

.35 

.35 

.35 

.35 

.35 

 .27 

.27 

.24 

.24 

.24 

.24 

.24 

.24 

.20 

.20

0.004 

.008 

.002 

.004 

.004 

.005 

.004 

-.004 

.005 

.003 

.003 

.003 

.01 

.006 

.01 

.008 

.008 

.02 

.OQ8 

-.006 

.005 

.004 

.003 

.003 

.003 

.002 

.002 

.003 

.005 

.003

0.158

February 1939

Discharge 

(secondfeet)

0.60 

.65 

.65 

.65 

.65 

.65 

.65 

.65 

.65 

.65 

.65 

.65 

.65 

.65 

.77 

.69 

.69 

.69 

.69 

.69 

.69 

.69 

.69 

.69 

.69 

.73 

.69 

.69

Sediment 

loads 

(tons)

0.04 

.04 

.04 

.04 

.02 

.3 

01 

.09 

.009 

.05 

.02 

.03 

.04 

.05 

.2 

.2 

.03 

.04 

.04 

.04 

.04 

.03 

.03 

.03 

.02 

.04 

.04 

.03

1.589

July 1939

0.24 

.20 

.24 

.27 

.27 

.24 

.20 

.24 

.20 

-.24 

.20 

.20 

.20 

.17 

.17 

.17 

.17 

.14 

.14 

.14 

.14 

.14 

.14 

.10 .10' 

.07 

.07 

.10 

.10 

.10 

.10

0.004 

.002 

002 

.002 

.006 

.005 

.008 

.01 

.001 

.001 

.003 

.003 

.001 

.002 

.003 

.003 

.003 

0 

0 

0 

.001 

.001 

.001 

.001 

.001 

0 

0 

0 

0 

0 

.001

0.065

March 1939

Discharge 

(secondfeet)

0.65 

.69 

.69 

.69 

.70 

.69 

.65 

.69 

.73 

.77 

.77 

.89 

1.0 . 

.89 

.93 

1.6 

2.5 

3.2 

4.6 

5.6 

5.5 

6.9 

8.2 

9.0 

9.9 

10 

9.9 

9.7 

9.4 

9.7 

9.9

Sediment 

loads 

(tons)

0.04 

.04 

.04 

.03 

.04 

.03 

.01 

.09 

.03 

.05 

.06 

.1 

.2 

.2 

.2 

1.3 

3.2 

5.4 

19 

20 

18 

49 

33 

38 

37 

32 31' 

30 

17 

13 

16

364.06

August 1939

0.07 

.07 

.07 

.07 

.07 

.07 

.10 

.07 

.10 

.07 

.07 

.07 

.07 

.07 

.17 

.14 

.14 

.07 

.07 

.07 

.07 

.07 

.07 

.07 

.07 

.07 

.07 

.07 

.07 

.07 

.07

0 

0 

0 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.002 

.002 

-.003 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.002 

.002 

.002

0.035

April 1939

Discharge 

(secondfeet)

10 

11 

11 

11 

9.4 

7.9 

7.9 

8.4 

8.2 

7.9 

6.8 

5.2 

3.0 

2.3 

2.1 

2.0 

1.9 

1.8 

1.7 

1.8 

1.6 

1.6 

1.6 

1.5 

1.4 

1.3 

1.3 

1.2 

1.3 

1.4

Sediment 

loads 

(tons)

22 

26 

26 

21 

19 

13 

6.4 

9.2 

27 

19 

14 

12 

2.0 

.7 

.4 

.7 

.3 

.2 

.2 

.4 

.1 

.1 

.1 

.09 

.07 

.06 

.1 

.04 

.1 

.2

220.46

September 1939

0.07 

.10 

.10 

.10 

.07 

.07 

.10 

.10 

.10 

.07 

.10 

.27 

.35 

.20 

.17 

.17 

.14 

.14 

.14 

.10 

.10 

.14 

.14 

.14 

.14 

.14 

.14 

.14 

.14 

.14

0.002 

002 

.001 

001 

.001 

.001 

.002 

.002 

.002 

.002 

.002 

.02 

.02 

.004 

.003 

.003 

.003 

.002 

.002 

.001 

001 

.002 

.002 

.092 

.002 

.002 

.004 

.004 

004 

.004

0.103

May 1939

Discharge 

(secondfeet)

1.2 

1.1 

1.0

' .93 

.85 

.81 

.81 

.77 

.69 

.61 

.57 

.60 

.57 

.57 

.57 

.57 

.73 

.57 

.54 

.50 

.50 

.50 

.46 

.38 

.38 

.35 

.31 

.31 

.27 

.31 

.35

Sediment 

loads 

(tons)

0.05 

.1 

.1 

.03 

.03 

.02 

.05 

.03 

.03 

.07 

.08 

.1 

.04 

.03 

.02 

.02 

.4 

.06 

.02 

.02 

.02 

.01 

.01 

.01 

.009 

.04 

.008 

.007 

.005 

.005 

.009

1.433

October 1939

0.17 

.20 

.24 

.24 

.27 

.35 

.27 

.24 

.24 

.24 

.20 

.20 

.20 

.20 

.24 

.38 

.38 

.38 

.38 

.38 

.38 

.35 

.35 

.35 

.42 

.38 

.38 

.42 

.38 

.17 

.14

0.002 

.002 

.003 

.003 

.004 

.02 

.01 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.002 

.002 

.002 

.002 

.002 

.002 

.002 

.003 

.003 

.004 

.003 

.001 

.001 

.001 

0 

0

0.082
102 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

PINE CREEK NEAR IDAHO CITY, IDAHO Continued

Day

1. ____

2.-.. 

3 ..

4....-. ..........

5.. ..................

6

7.. ....... ........

8

9....................

10.. ........... ....

11...................

12. .

13...................

14 .

15. ..................

16..:................

17.. .................

18.1.................

19..... . .

20

21. .............

22 .

23--....-...-.......

24...................

25---.._--.-..--.

26... -. ..

27

28...................

29.........

30...................

31...................

Total... .......

November 1939

Discharge 

(secondfeet)

0.14 

.14

.14 

.14 

.14 

.14 

.17 

.17 

.14 

.14 

.17 

.20 

.20 

.17 

.20 

.20 

.20 

.20 

.20 

.20 

.27 

.27 

.31 

.31 

.27 

.31 

.31 

.27 

.27 

.27

..........

Sediment 

loads 

(tons)

0 

0 

0 

0 

0 

0 

0 

0 

.002 

.002 

.003 

.003 

.003 

.003 

.004 

.004 

.004 

.004 

.004 

.004 

.002 

.002 

.003 

.003 

.002 

.003 

.003 

.002, 

.002 

.002

0.064

December 1939 -A 

Discharge 

(secondfeet)

0.27 

.27 

.27 

.27 

.27 

.35 

.31 

.31 

.57 

.46 

.61 

.42 

.42 

.38 

.46 

.61 

.85 

.54 

.46 

.46 

.38 

.31 

.35 

.31 

.30 

.35 

.38 

.38 

.38 

.46 

.54

..... 

Sediment 

loads 

(tons)

0.001 

.001 

.001 

.001 

.001 

.002 

.009 

.002 

.1 

.02 

.03 

.008 

- .008 

.007 

.009 

.04 

.06 

.04 

.01 

.01 

.008 

.007 

.008 

.005 

.003 

.004 

.004 

.004 

.004 

.005 

.03

0.442

January 1940

Discharge 

(secondfeet)

0.65 

.87 

1.0 

.85 

.73 

.54 

.57 

.65 

.61 

.61 

.54 

.57 

.54 

.54 

.50 

.46 

.42 

.42 

.42 

.42 

.42 

.42 

.42 

.42 

.38 

.46 

.54 

.46 

.38 

.35 

.31

..........

Sediment 

loads 

(tons)

0.03 

.2 

.3 

.04 

.04 

.03 

.03 

.009 

.008 

.02 

.04 

.04 

.04 

.04 

.009 

.009 

.008 

.006 

.006 

.006 

.002 

.002 

.002 

.003 

.003 

.004 

.004 

.008 

.006 

.006 

,003

0.954

.February 1940

Discharge 

(.secondfeet)

0.35 

.38 

.50 

. .54 

.57 

1.2 

1/2 

.97. 

.96 

1.5 

1.4 

1.0

... 

Sediment 

loads 

(tons)

0.003 

.003 

.004 

.004 

.005 

.5 ' :I- .1

1.0 1.1

2.1

5.319

PINE CREEK ABOVE BARRY PLACER DIVERSION NEAR IDAHO CITY, IDAHO

Discharge and total sediment 'loads, February to June 1940

Day

1

2

3....

4

5..

6... ..........

7.

8...... .

8

10.... ........

11 

12 .

13............

14............

15............

16. ..- .

17 

18 ........

19

20...........

21 

22 

23... ......

24 

25... .........

26.... ........

27... .........

28 

29

30 

31 

Total .-

February 1940

Discharge 

(secondfeet)

0.85 

.86 

.70 

.60 

.58 

.54 

.45 

.35 

.30 

.43 

.43 

.39 

1 .70 

1.6 

6.5 

11 

8.4

.........

Sediment 

loads 

(tons)

0.2 

.2 

.1 

.2 

.09 

.1 

.2 

.4 

.69 

.05 

.06 

.03 

.8 

4.0 

130 

167 

47

350. 52

March 1940

Discharge 

(secondfeet)

5.8 

5.1 

4.5 

3.9 

3.4 

3.2 

3.5 

5.3 

5.3 

4.9 

4.1 

3.5 

3.2 3.3" 

2.9 

2.4 

2.6 2.6- 

2'. 6 

2.6 

2.6 

2.6 

2.6 

2.6 

4.3 

9.4 

27 

17 

12 

11 

15

.........

Sediment 

loads 

(tons)

22 

6.6 

4.7 

1.9 

1.0 

11 

15 

11 

17 

11 

14 

7.0 

5.3 

4.5 

5.2 

1.1 

1.7 

1.1 

1.0 

1.6 

2.3 

1.9 

1.6 

1.4 

25 

315 

2; 840 ' 

1,100 

570 

375 

405

5,780.9

April 1940

Discharge 

(secondfeet)

16 

15 

13 

11 

11 

6.9 

6.4 

6.4 

6.6 

6.2 

6.0 

3.9 

3.2 

3.0 

2.9 

2.6 

2.5 

2.0 

2.1 

2.4 

2.4 

2.7 

1.5 

1.4 

1.4 

2.0 

1.8 

1.5 

1.6 

3.7

.........

Sediment 

loads 

(tons)

364 

209 

179 

151 

94 

20 

19 '18 

21 

18 " 

8.0 

3.8 

.7 

.3 

 .3 

.09 

.3 

1.2 

.6 

1.6 

1.7 

3.0 

.4 

.1 

.1 

1.8 

.2 

.09 

.1 

11

1, 128. 38

May 1940

Discharge 

(secondfeet)

1.1

1.1 

1.1 

1.1 

1.3 

1.1 

1.1 

1.0 

1.2 

.90 

1.1 

.90 

1.1 

.62 

.82 

.97 

1.8 

'.78 

.62 

.51 

.47 

1.0 

.51 

.43 

.43 

.39 

.35 

.43 

.43 

.35 

.35

.........

Sediment 

loads 

(tons)

0.08 

.1 

.06 

.06 

.3 

.08 

.9 

' 3.1 

7.9 

3.4 

9.5 

1.2 

10 

.05 

6.5 

2.9 

19 

1.0 

.4 

.02 

.01 

4.1 

.03 

.01 

.006 

.009 

.009 

.009 

.01 

.004 

.005

70. 752

June 1940

Discharge 

(secondfeet)

0.35 

.32 

.32 

.39 

.35 

.32 

.35 

.29 

.25 

.29 

.25 

.25 

.22 

.22 

.22 

.22 

.19 

.16 

.16 

.16 

.14 

.14 

.14 

.16 

.14 

.14 

.14 

.14 

.14 

.14

.........

Sediment 

loads 

(tons)

0.006 

.008 

.05 

.3 

.3 

.3 

.2 

.1 

1.0 

2.9 

2.6 2.5' 

1.2 

1.0 

1.0 

.1 

.1 

.2 

.09 

.05 

.04 

.1 

.04 

.1 

.08 

.06 

.03 

.04 

.06 

.03

14.584
DAILY DISCHARGE AND SEDIMENT LOADS 103

DAVIS PLACER DIVERSION FROM PINE CREEK NEAR IDAHO CITY, IDAHO

Discharge, in second-feet, April 1989 to June 1940 ,

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.- 

April 

1939

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

.5 

1.5 

3.5

3.5 

 3.3

3.5 

| 3.2

I 2.8

3.0 

3.5

Day

1 -

2 ---------

3. 

4 

5 ... .....

6 ... . 

 7 .

8 ___ _--. 

9

10- _ - -

11 

12 _ __. _ J._ 

13 

14... ...... ..... ..... .......

15. . ,.

16- _ _. _ j...... ... .... ..

17-

IS 

19 

20 

21 __ ----- .

22 _. 

23 ..

24 . 

25 

26 

27 

28 - __ 

29-r - ..... .. .... ....

30- .

31 ..._!. 

May 1939

3.0 

2.7 

2.5 

2.3 

2.2 

2.0 

1.8 

1.8 

1.8 

1.5 

1.6 

1.4 

1.4 

1.2 

111 

1.2 

.9 

.9 

2.0 

1.8 

1.8 

1.9 

1.8 

f 1.5 

1 1.5

1 1 ' 4 

1 l- 2 

( 1-1 

1.1 

.9 

.9

December 1939

0.1, 

.2 

.1 

.2 

.1 

.3 

.3 

.3 

.6 

.6 

.7 

 .6 

.5 

.3 :J

.6 

.3 

.2 

.3 

.3 

.2 

.3 

.2 

.1 

.2 

.1 

.1 

.1 

.1 

.2

June 1939

0.9 

.8 

 .7 

.7 

.7 

.9 

.7 

.8 

.9 

.8 

.7 

.7 

.4 

.4 

.4 

.4 

.7 

.5 

.4 

.4 

.4 

.4 

.4 

.4 

.4 

.3 

.3 

.3 

.2 

.2

January 

1940

0.4 '.6 

.8 

.8 

.6 

.4 

.4 

.4 

.4 

.4 

.3 

.3 

.3 

.3 

.3 

.3 

.3 

.3 

.1 

.1 

.1 

.1 

.2 

.2 

.3 

.4 

.4 

.4 

.2 

.4 

.5

July 1939

0.2 

.2 

.2 

.3 

?4 

.3 

.3 

.3 

.2 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

.05 

.05 

.1 

.05 

.05 

.05

February 

1940

0.4 

.5 

.4 

.4 

.4 

1.3 

.6 

.0 

.5 

1.3 

.9 

.7 

.6 

.5 

.5 

.5 

.5 

.4 

.4 

.4 

.4 

.4 

.4 

.4 

.4 

.6 

.9 

1.6 

1.0

August 

1939

0.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

0 

0 

0 

 0 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05

March 

1940

0.4 

.3 

.2 

.2 

.2 

.1 

.1 

.2 

.3 

.5 

.5 

.5 

.5 

.4 

.4 

1.0 

1.4 

1.7 

1.8 

1.8 

2.0 

2.0 

2.2 

2.3 

6.0 

5.0 

0 - 

1.4 

1.5 

1.6 1 Q

September 1939

0.05 

.06 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.3 

.4 

.2 

.1 

.1 

.1 

.1 

.05 

.05 

' .05 

.05 

.05 

' .05 

.05 

.05 

.05 

.05 

.05 

.05

April 

1940

2.2 

1.9 

1.6 

2.0 

3.0 

2.6 

2.5 

2.5 

3.4 

3.2 

1.9 

3.2 

3.9 

3.8 

3.7 

3.4 

4.0 

4.7 

4.1 

4.4 

4.3 

4.0 

4.8 

4.8 

4.8 

4.0 

6.6 

6.3 

5.9 

2.2

October 

1939

I 0.1 

.2 

.1 

.1 

.1 

.2 

.1 

.1 

.1 

.1 

.1 

.1 

.1 

1 .1 

.1 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

.2 

.2

May 1940

4.7 

4.7 

4.7 

5.4 

4.2 

4.5 

4.4 

4.3 

4.7 

4.5 

4.2 

5.7 

5.6 5.9' 

5.1 

. '5.6 

2.8 

4.3 

4.3 

4.4 

4.1 

3.2 

3.5 

3.4 

3.2 

3.1 

2.9 

2.8 

2.5 

2.2 

1.7

November 1939

0.2 

.2 

.2 

.2 

.2 

\2 

.2 

.2 

.2 

.2 

.2 

.2 

.1 

.05 

.1 

.1 

.1 

.1 

.1 

.1 

.4 '.2 

.2 

1 .1 

.1 

.1 

.2 

.1 

.1 

.1

June 1940

, 2.0 

,1.9 

1.8 

2.0 

1.8 

1.7 

1.8 

1.5 

1.4 

1.4 

1.2 

.9 

1.0 

1.0 

.8 

" .8 

.5 

.4

i : 5

.5 

.5 

.6 

.5 

.3 

.4 

.3 

.3 

.4 

.4
104 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN 

DIVERSION FROM THORN CREEK INTO PINE CREEK NEAR IDAHO CITY. IDAHO

Day

1.. ___ _ ..... _

i::::::::::::::::::::::r.::::::

4 .

.5 

6 .

7............ ................

s........... ........ ......

'9..................... ..........

10.......... .................

n..........- .... ............

12......... .....................

13..............................

14.... ... 

15

16............. ..............

17-. .....'.. .....................

1%.... .......................... 

W...... ....................... .

20 ._- . -

21 

 22... ........ ...... .............

 00

24 

25 

26 

27 

28

29.. 

Oft

31 

Day

1

2

3..... . .

4 

6. . 

6 

7.. ........ ... .. -

8 - 

9 -

10 

]] 

12 

13 

14.-.--.-.---.. _ ------- _ -.-.

15 

16 . T 

17 

18 

19 

20.... 

21- - ..... u... 

22... ........ ......... ..........

23 

24 .

25 - 

26 

97

28 

29 . - 

30 ..... .........

31 

May 

1939

0

0 

0

0

0

0

0

0 

0

0

1 0

0

9 .

0

0

0

0

.1 

1.1

1.0

.9

.8

.7

.5

\ ' 4

f -3

\ ' 2

December 1939

June 

1939

} 0.2

 .1

0

0

0

0

} - 1

0

0

0

0

0

0

f 0

I 0

0 ) n

\ o

I 0

\ 

January 

1940

' July 

1939

i

February 

1940

August 

1939

March 

1940

September 1939

,

April 

1940

0

0

0

' 0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

1

1 2.2

October 

1939

May 

1940

. o

2

0

4.5

4.4

3. 6

2 9

Jj. £i

1.5

\ »

November 1939

June 

1940

1

1 "

.7

.6

.5

1 "

.2

.2

.2

1 ,

1

NOTE. No flow July 1939 to March 1940.
DAILY DISCHARGE AND SEDIMENT LOADS 105

ELK CREEK NEAR IDAHO CITY, IDAHO

Discharge and suspended sediment loads, January 1939 to February 1940

Day

1. ... .

2... ........ -

3.............

4

5.. . .... ...

6.. ...........

g

9 . . .

10... ....... ..

11. 

12--.----..--.

13.... .

14 

15.. .....

16 . 

17 

18 

19.. ........ ..

20 

21 

22 --------

23... --.

24 ---

25 ....

26- 

27-- . --.

28 --.

29 

30 .

31..... .......

Total -

Day

1 -.-- ..

2

3-. -.--

4 

5 

6 .... ......

7

8 ......

9..... ....

10 

11 

12- - 

13 . ..

14 -

15 ....... ..

16

17 

IS 

19 

20 -..

21 

22 

23 

24. 

25... .........

26--- -..

27 .

28 

29 

30-. - ..

31 -. .

Total. .

January 1939

Discharge 

(secondfeet)

7.6 

8.7 

6.8 

S.I 

8.4 

8.7 

8.7 

9.0 

9.0 

8.7

8.1

7.5

Sediment 

loads 

(tons)

0.1 

.2 

.1 

.02 

.07 

.07 

.09 

.4 .4- 

.1

.4

.3

June 1939

8.4 

8.7 

5.2 

3.5 

2.2 

3.5 

5.4 

6.1 

7.6 

7.8 

8.7 

7.6 

9.5 

9.5 

12 

14 

13 

11 

12 

9.2 

9.5 

9.8 

5.2 

6.5 

6.5 

7.8 

6.5 

4.9 

5.8 

M

71 

164 

25 

20 

10 

24- 

30 

16 

398 

36 

13 

64 

31 

65 

115 

62 

50 

32 

27 

23 

48 

26 

55 

118 

25 

49 

43 

17 

25 

25

1,707

February 1939

Discharge 

(secondfeet)

7.5 

7.5 

8.0 

8.4 

8; 1 

8.1 

8.1 

7.8 

7.8 

8.1 

8.1 

8.1 

7.8 

7.8 

8.1 

7.8 

7.8 

 7.8 

7.8 

8.4 

8.7 

8.4 

8.4 

8.4 

8.1 

9.0 

8.7 

8.4

Sediment 

loads 

(tons)

0.2 

.2 

.3 

.3 

.2 

.06 

.04 

.02 

.1 

.1 

.3 

.5 

.4 

.1 

.3 

.3 

.3 

.4 

.5 

.6 

.5 

.5 

.2 

.2 

.2 

.5 

.4 

.4

July 1939

0.9 

.7 

1.3 

1.3 

1.7 

2.6 

1.8 

3.7 

2.9 

2.0 

2.9 

2.0 

1.5 

1.3 

3.3 

2.4 

2.8 

3.1 

2.7 

3.7 

3.7 

3.3 

4.1 

3.9 

2.7 

3.1 

4.3 

2.7 

3.5 

1.7 

2.8

0.7 

.2 

2.8 

3.0 

1.6 

7.1 

5.0 

37 

44 

38 

61 

36 

13 

16 

19 

12 

12 

41 

24 

37 

43 

21 

11 

28 

32 

13 

17 

14 

13 

3.8 

8.7

614.9

March 1939

Discharge 

(secondfeet)

8.4 

8.1 

8.1 

8.1 

8.7 

8.7 

8.4 

8.1 

7.8 

- 8.4 

9.0 

9.2 

10 

9.5 

9.2 

11 

17 

19 

40 

58 

62 

67 

74 

79 

83 

74 

71 

76 

71 

74 

76

Sediment 

loads 

(tons)

0.2 

.3.'4 

.7

:!

.6

.2 

.1 

.5 

1.8 

.5 

.8 

1.7 

.2 

3.0 

14 

42 

138 

155 

133 

217 

252 

266 

364 

254 

246 

232 

160 

212 

250

2, 947. 0

August 1939

3.1

2.9 

1.8 

1.0 

..5 

1.2 

1.3 

1.2 

.7 

.8 

2.0 

2.4 

1.7

. :?

.5 

.2 

,6 

.2 

.7 

1.5 

1.0 

.5 

.4 

.3 

.3 

.4 

.3 

..4 

.4 

.2

8.5 

8.2 

3.8 

.9 

.4 

2.7 

2.3 

.9 

.6 

.6 

12 

18 

13 

12 

4.6 

.4 

.2 

2.8 

.1 

1.0 

3.7 

1.3 

.5 

.4 

1.0 

.4 

.2 

.4 

.9 

1.7 

.5

104.0

April 1939

Discharge 

(secondfeet)

78 

76 

78 

84 

78 

71 

68 

68 

65 

58 

55 

54 

48 

46 

47 

46 

46 

51 

54 

55 

59 

62 

64 

60 

50 

47 

48 

54 

60 

64

Sediment 

loads 

(tons)

241 

209 

180 

164 

90 

71 

102 

90 

84 

66 

48 

50 

30 

29 

46 

29 

47 

43 

53 

53 

76 

57 

55 

48 

29 

20 

30 

44 

66 

75

2,225

September 1939

0.2 

.2 

.2 

.2 

.3 

.3 

.3 

.3 

.2 

.2 

.3 

1.1 

2.7 

1.3 

1.7 

1.5 

.7 

1.0 

2.2 

1.2 

1.5 

1.0 

1.2 

1.2 

1.8 

1.2 

1.2 

1.5 

1.5 

1.5

0.3 

.5 

.4 

.2 

.2 

.2 

.2 

.3 

.2- 

.3 

.5 

11 

16 

3.6 

12 

17 

6.8 

4.8 

16 

8.7 

7.2 

3.2 

4.9 

13 

26 

14 

7.9 

7.2 

16 

16

214.6

' May 1939

Discharge 

(secondfeet)

59 

58 

56 

52 

56 

55 

41 

30 

25 

30 

30 

18 

18 

16 

24 

20 

7.3 

6.8 

- 7.8 

8.7 

8.1 

8.1 

7.T) 

6.3 

6.3 

6.1 

8.1 

9.5 

10 

12 

11

Sediment 

loads 

(tons)

47 

27 

34 

35 

149 

124 

75 

29 

30 

65 

156 

61 

165 

30 

98 

40 

14 

14 

19 

15 

4.5 

4.5 

60 

192 

86 

73 

96 

65 

142 

126 

125

2,201.0

October 1939

1.0 

.7 

2.2 

1.7 

1.7 

2.2 

.2.2 

1.7 

2.4 

2.4 

2.9 

3.3 

.7 

.7 

2.4 

1.8 

2.2 

3.3 

3.1 

3.1 

2.9 

2.0 

2.2 

3.5 

3.1 

3.3 

2.5 

2.7 

2.2 

2.5 

2.5

7.5 

14 

45 

34 

38 

20 

27 

32 

45 

18 

25 

16 

1.2 

1.6 

21 

10 

12 

16 

26 

26 

25 

21 

28 

23 

22 

19 

17 

28 

27 

32 

24

701.3
106 DISCHARGE AND SEDIMENT, BOIS& RIVER BASIN 

ELK CREEK NEAR IDAHO CITY, IDAHO Continued

Day

I.. ................ .-

2.. ..................

3. 

4 

5.. ............ ......

6.. ..................

7. . ..................

8.... ....... ......

9 

10 -

11- 

12--' ... ... 

13- 

14. 

15 

16 

17. 

18. 

20 

21- 

22 

23 

24 

25- 

26 

27- J : _ .... .

28 

29. -.

30 ___ __ - _ -

31-. 

Total.. ___ 

November 1939

Discharge 

(secondfeet)

2.9 

1.3 

1.7 

2.0 

1.7 

1.3 

1.7 

1.3 

1.8 

2.0 

3.1 

5.4 

3.3 

3.9 

2.7 

3.6 

7.3 

5.8 

4.3 

6.1 

4.5 

4.5 

5.2 

4.7 

5.2 

4.7 

3.9 

2.5 

3.6 

5.6

Sediment 

loads 

(tons)

15 

7.5 

13 

5.7 

3.8 

6.1 

10 

1.8 

2.8 

4.1 

19 

37 

18 

5.1 

3.6 

12 

27 

26 

34 

i 29 

12 

9.5 

8.9 

6.8 

11 

4.7 

4.7 

1.9 

4.1 

11

355.1

December 1939

Discharge 

(secondfeet)

4.5 

5.2 

4.5 

5.6 

4.1 

3.7 

4.3 

5.6 

8.1 

8.5 

9.5 

7.6 

5.4 

5.2 

5.6 

8.4 

11 

7.0 

6.3 

5.2 

4.3 

4.5 

8.1 

7.0 

5.5 

7.3 

9.0 

7.6 

 11 

8.4 

11

Sediment 

loads 

(tons)

5.8 

7.2 

11 

10 

15 

17 

18 

44 

79 

42 

38 

52 

38 

26 

50 

41 

36 

31 

26 

12 

21 

6.9 

9.6 

16 

4.8 

9.9 

12 

6.6 

15 

13 

22

January 1940

Discharge 

(secondfeet)

11 ' 20 

18 

14 

12 

7.0 

8.0 

11 

 9.5 

9.5 

9.5 

8.7 

8.0 

7.5 

7.5 

7.6 

9.8 

8.0 

7.0 

7.6 

6.8 

7.3 

7.3 

6.3 

6.8 

7.8 

7.9 

8.4 

8.0 

8.0 

8.0

Sediment 

loads 

(tons)

27 

66 

31 

22 

16 

5.0 

8.2 

8.6 

14 . 22 

8.2 

9.8 

3.6 

2.5 

3.2 

3.1 

4.4 

2.9 

2.7 

2.6 

2.7 

3.8 

6.2 

6.0 

5.1 

8.9 

13 

17 

18 

9.2 

12

364.7

February 1940

Discharge 

(secondfeet)

. 8.0 

8.0 

8.1 

8.1

Sediment 

loads 

(tons)

40 

22 

22 

27

111
DAILY DISCHAKGE AND SEDIMENT LOADS 107

GOLP HILL PLACER DIVERSION FROM ELK CREEK NEAR IDAHO CITY, IDAHO

Discharge, in, second-feet, April 1939.to February 1940

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 .

April 

1939

' 0 

0 

Q 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 . 

0 

5.0 

11 

11

May 

1939

12 

12 

14

17 

11 

4.6 

13 

17 

19 

15 

11 

24 

26 

27 

9.1 

9.3 25- 

25 

26 

24 

23 

23 22 - 

22 

21 

20 

20 

19 

20 

20 

19

June" 

1939

19 

18 

' 18 

17 

17 

14 

7.6 

7.2- 

8.4 

8.0 

7.8 

7.8 

8.0 

7.6 

7.8 

,8.0 

8.4 

8.2 

9.2 

8.4 

7.6 

7.2 

6.8 

6.8 

6.8 

6.0 

6.0 

5.5 

8.0 

8.0

July 

1939

7.8 

7.6 

8.0 

8.4 

8.4 

8.0 

7.2 

7.0 

6.8 

5.5 

6.6 

7.2 

7.0 

7.0 

 6.2 

2.2 

4.3 

6.0 

5.8 

6.2 

5.8 

, 6.4 

6.0 

6.0 

6.0 

4.7 

2.8 

2.91 

2.8 

3.2 

2.9

August 

1939

3.9 

5.1 

4.9 

4.9 

4,6 

4.9 

4.4 

4.6 

4.7 

4.6 

4.6 

4.6 

4.6 

4.6 

3.9 

3.9 

4.2 

4.0 

4.2 

4.4 

4.0 

3.7 

4.2 

4.2 

4.7 

4.6 

4.6 

4.2 

4.4 

4.2 

4.2

September 

1939

4.2 

4.6 

4.7 

4.2 

4.4 

,4.6 

4.2 

4.2 

4.2 

4.4 

4.2 

7.6 

7.6 

6.0 

5.7 

5.3 

5.3 

4.7 

4.9

5.0

October 

ber 

1939

6.0 

6.8 

7.0 

7.2 

7.4 

7.6 

6.0 

5.5 

5.5 

5.5 

5.7 

5.7 

5.7 

5.7 

5.5 

5.7

5.5

6.0 

5.5

November 

1939

1 5.0

4.7

i 5.0

5.1 

5.0 

4.9 

4.8 

4.7 

4.7 

4.7 

2.7

1 o

0 

0 

0 

0 

0 

0 

0

; o

0 

0 

0 

0 x o

December 

1939

January 

v 1940

'

February 

. 1940

,

NOTE. No flow December 1989 to February 1940.

GOLD HILL PLACER DIVERSION RETURN FLOW TO ELK CREEK NEAR IDAHO CITY,

IDAHO

Discharge, in second-feet, May 1939 to February 1940

Day

1 ________ .

2 ___ . 

3. ..... ... 

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 .

May 

1939

0

0

0

0

0

0

0

0

0

0

0

0

0

0

-0*0

0

0

0

0

0

0

0

.1

1.5

1.4

1.6

1.8

1.8

Q

1.4

June 

1939

1.0

1.0

2.2 l.'S

2.4

2.2

0

0

00'

0

1.5

1.4

1.6

1.4

1.3

1.5

1.6

 1.6

1.7

1.8

1.6

0

1.5

1.4

1.2

1.8

2.2

1. 1

July 

1939

0

0

.6

1.2

0

0

0

0

0

0

0

0

0

0

0

Ov

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

August 

1939

>

September 

1939

October 

1939

0

0

0

0

0

0

 0

0

0

0

0

0

0

0

\ 2.5

3 A

November 

1939

2.5

/ 1.0

0

0

0

0

0

0

0

0

0-

0

0

0

0

0

December 

1939

January 

1940

February 

1940

NOTE.T-NO flow during August, September, and December 1939 and January and February 1940. 

758529 48 8
108 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

RUBOW DIVERSION NO. 2 FROM ELK CREEK NEAR IDAHO CITY, IDAHO

Discharge, in second-feet, May 1939 to January 1940

Day

I.. .. ... _ ............

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 

May 

1939

0

0

0

0

0

0

0

0

0

0

0

2.0

2.0

2.0

0

0

0

0

0

0

0

.2

.2

0

0

.1

/ " 3

' .2

.2

.2

June 

1939

0

0

0

0

0

0

0

0

0

0

0

0

2.3

s i

3.5

3.5

4.0

2.3

4.6

1 4

2.2

2.5

.8

.9

.8

.3

0

.7

July 

1939

3.8

% 9

3.5

4.4

4.6

3.8

2.3

.4

.7

1.1

.8

.2

.4

.4

.2

0

1.9

1.3

.8

.8

.8

.7

.7

3.3

2.5

.6

1.6

1.6

2.3

2.2

August 

1939

2.2

.2

.4

.8

.5

.3

.3

.3

.2

.4

.4

1.1

.8

.2

.6

.4

.4

.3

.4

.4

.5

.8

1.7

.2

/ .2

9'$

.2

.2

.3

September 

1939

0.2

.2

.2

.2

.2

.2

.2

.2

.2

.2

.1

.1

0

1.4

1.4

1.4

0

0

.6

.5

.6

.2

.3

0

.2

0

0

October 

1939

0

.2

.1

.6

.6

1.5

1 Q

.9

.4

.1

.3

.3

.4

. 0

.1

0

0

0

.2

.4

.4

.5

0

.7

0

.2

.6

.6

.2

.9

November 

1839

0

.6

0

0

.1

.1

.2

.7

.3

.1

1.5

.3

.3

.4

.2

1.5

0

0

1.0

1.0

.9

2.0

.9

1.0

1.3

1.2

3.3

3.5

2.1

.9

December 

1939

0.7

.7

.9

.7

.9

.7

1.0

1.2

2.2

2.3

2.0

1.2

. 1.2

1.2

2.2

2.7

3.3

2.3

2.3

3.6

4.2

2.2

2.3

.8

0

0

0

0

0

0

0

January 

1940

0.6

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

RUBOW DIVERSION. NO. 3 FROM ELK CREEK NEAR IDAHO CITY, IDAHO

Discharge, in second-feet, March 1939 to February 1940

Day

1 

2 

3. ..... .....

4 

5... ....... ....

6 -

7 ~

8 -- 

9 -..-

10 --

11 _---

12 .. 

13- 

14 . -

15 _ .......

17- 

18 

19 '-

20 

21 ------

22 

23 ..

24 .

25- ...- -.

26 .- 

27 

28- 

29 

30 

31 

March 

1939

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

5

April 

1939

5

, 

May 

1939

f 5.0

5.0

5.0

5.0

6.0

6.0

6.1

,6.3

5.5

5.7

5.2

4.8

C A

5.0

6.4

5.4

3.7

3.6

3

^J

4.2

4.7

5.5

4 7

4.7

4

O

5.0

s.a

5.0

5.0

4.8

June 

1939

4.7

4.4

4.4

5.0

4, 7

f, Q

c 7

% 7

5.7

% 4

0

0

0

0

0

0

0

0

0

0

4.8

4 R

4.8

o o

4.8

A Q

4.4

4.4

July 

1939

4 9

4.2

4.2

4.4

4.2

4.0

4.2

4.2

4.2

3.3

3 A

9 Q

2.8

5.0

9 fi

.8

.8

.8

.7

.8

.8

.8

.8

.8

August 

1939

O

D

.7

.79 n

1.9

2.2

1 Q

1.9

2.2

9 4

1.0

.9

.9

1.4

5.6

2.9

2.4

9 7

2.9

9 Q

2.4

2.9

2.8

2.9

2

Q

2.8

2

D

2 7

2 a

9 n

Septen> 

ber 

1939

9 4

2.7

2.4

2.6

2.4

2.6

2.7

2.6

2.6

2.6

2.6

3.9

4.8

3.4

2.8

2.8

2.8

2.6

9 7

2.7

2 7

9 7

2.7

2.8

2.8

9 Q

9 7

9 7

2

0

9 Q

October 

1939

s n

3.4

3.3

3.2

3.4

3.4

^ 4

3.2

3.0

3.0

2.9

2.9

2.8

3.0

2.9

^ n

2.9

3.2

2.8

2.7

2.7

2.7

2.7

2.9

3.2

9 4

3.7

4.0

3.3 3 n

2.9

November 

1939

2.9

2.9

3.0

3.0

2.8

2.9

2.9

2.9

3.4

2.3

0

0

0

0

0 *

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

December 

1939

0

0

0

0

0

.6

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

January 

1940

«

Febr 

ruary 

1940

T

NOTE. No flow January and February 1940.
DAILY DISCHARGE AND SEDIMENT LOADS 109

ELK; CREEK ABOVE GOLD HILL PLACER DIVERSION NEAR IDAHO CITY, IDAHO

Discharge and total sediment loads, February to June 1940

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 

Total. .

February 1940

Discharge 

(secondfeet)

6.9 

 7.4' 6.7 

7.4 

7.2 

6.9 7.7

7.1 

7.0 

8.0 7.4' 

6.9 

6.5 

6.9 

6.5 

6.0 

5.5 

6.0 

6.5 

6.2 

6.5 

7.7 

9.4 

14 

22 

21

.........

Sedi- ment' 

loads 

(tons)

0.2 

.04 

1.1 

.1 

.06 

.2 

2. 

.3 

.2 

.3 

.2 

.4 

.3 

.4 

.2 

.06 

.1 

.1 

.05 

.1 

.2 

.4 

2.0 

7.2 

12 

3.5

29.91

Marcb 1940

.Discharge 

(second- 

' feet)

16 

14 

13 

12 

12 

11 

11 

19 

17 

15 

14 

13 

12 

 12 

12 

13 

14 

15 

16 

19 

22 

26 

32 

35 

61 

74 

95 

62 

48 

48 

65

Sediment 

 loads 

(tons)

-2.9 

1.0 

1.2 

.9 

.6 

.7 

.7 

5.1 

3.2 

1.9" 1.3 

5.5 

2.6 

1.7 

1.2 

2.1 

2.2 

2.6 

2.8 

8.1 

12 

16 

27 

15 

99 

108 

180 

39 

24 

32 

61

661.3

April 1940

Discharge 

(second- 

.feet)

58 

51 

45 

41 

41 

39 

38 

39 

42 

41 

42 

45 

55 

70 

69 

61 

58 

60 

65 

63 

. 57 

56 

53 

49 

48 

50 

53 

49 

45 

42

.........

Sediment 

loads 

(tons)

88 

27 

28 

22 

17 

14 

16 

17 

26 

21 

27 

52 

 76 

122 

114 

78 

38 

43 

69 

68 

61 

46 

20 

18 

15 

18 

33 

26 

13 

12

1,225

May 1940

Discharge 

(secondfeet)

41 

45 

51 

50 

45 

44 

45 

44 

46 

. 53 

61 

65 

63 

58 

56 

52 

51 

46 

45 

44 

42 

41 

41 

41 

42 

41 

38 

36 

36 

34 

33

 

Sediment 

loads 

(tons)

17 

28 

18 

24 

10 

13 

8.0 

18 

15 

53 

78 

71 

49 

38 

41 

31 

20 

15 

9.8 

19 

21 

32 23- 

13 

12 

22 

33 

23 

29 

9.2 

18

811.0

June 1940

Discharge 

(secondfeet)

32 

31 

30 

29 

28 

25 

25 

24 

22 

21 

20 

19 

19 

18 

17 

16 

15 

14 

14 

13 

12 

12 

11 

11 

11 

11 

10 

9.8 

9.3 

9.3

 

Sedi- . ment 

loads 

(tons)

18 

8.2 

7.9 

6.2 

11 

8.8 

8.2 

7.4 

2.4 

3.8 

2.0 

2.6 

3.0 

1.7 

1.1 

.6 

1.7 

. .9 

1.2 

.9 

.9 

.8 

.4 

.3 

.5 

.4 

.5 

.4 

.4 

.3

102.5
110 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

NEW YORK CANAL NEAR BARBER, IDAHO

Discharge and suspended sediment loads, February 1939 to February 1940

Day

2... - ~

3 

4

5

6 ..

7 

8 . ....

ft 

10 

11 __ . _ ...

12____. ._,.._.

13 

14... _ .. ..-

15 

16 

17 

18 

19. 

20 

21 

22 __ . _ .. ..

23-r _ 

24 

25 

26 

27 ..

28 _. 

29 

30 

31 

Total..

February 1939

Discharge 

(secondfeet)

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

130 

360 

i 430 

560 

- 560 

683 

883 

1,030 

1,110 

1,170 

1,230

Sediment 

loads 

(tons)

0 

0 

0 

0 

0 

0 

 0 

0 

0 

0 

0 

6 

0 

0 

0 

0 

0 

18 

51 

109 

91 

51 

94 

114 

156 

96 

95 

96

971

March 1939

Dis- . 

charge 

(secondfeet)

1,210 

1,240 

1,240 

1,240 

1,220 

1,220 

1,230 

1,230 

1,400 

1,430 

1,380 

1,320 

1,280 

1,170. 

1,160 

1,260 

1,280 1,200- 

1,160 

731 

0 

0 

0 

0 

0 

0 

140 

700 

1,070 

1,110 

1,260

Sediment 

loads 

(tons)

131

117 

164 

174 

86 

132 

86 

166 

280 

328 

320 

356 

411 

322 

351 

459 

546 

797 

1,100 

928 

0 

0 

0 

0 

0 

0 

113 

575 

719 

617 

1,330

10, 608

April 1939 -

Discharge , 

(secondfeet)

V

1,330 

1,320 

1,320 

1,430 

1,630 

1,760 

1,800 

1,870 

2,030 

2,140 

2,240 

2,320 

2,320 

2,340. 

2,400 

2,480 

2,560 

2,640 

2,700 

2,700 

2,700 

2,720 

2,750 

2,750 

2,720 

2,680 

2,660 

2,680 

2,740 

2,780

Sediloads 

loads 

(tops)

1,020 

684 

584 

764 

651 

646 

423 

475 

696 

689 

689 

595 

514 

449 

661. 

623 

574 

727 

700 

663 

56S 

573 

446 

453 

514 

441 

373 

376 

399 

570

17,441

May 1939

Discharge 

(secondfeet)

2,790 

2,840 

2,830 

2,840 

2,860 

2,860 

, 2,850 

2,840 

2,810 

2,800 

2,800 

2,780 

2,760 

2,760 

2,740 

2,720 

2,720 

2,740^ 

2,720 

2,720 

2,620 

2,240 

2,220 

2,140 

2,030 

1,800 

1,600 

1,540 

1,560 

1,750 

2,010

Sediment 

loads 

(tons)

572 

529 

451 

575 

456 

324 

 416 

391 

258 

219 

219 

180 

238 

246 

178 

213 

176 

170 

206 

198 

241 

139 

126 

162 

115 

136 

99 

100 

93 

104 

136

7,666

June 1939

Dis- 

.oharge 

(secondfeet)

2,030 

1,810 

1,530 

1,300 

1,280 

1,260 

" 1,210 

1,190 

1,200 1,190- 

1,150 

1,200 

1,300 

1,340 

1,470 

1,450 

1,360 

1,260 

1,200 

1,200 

1,220 

1,340 

1,440 

1,520 

1,600 

1,630 

1,630 

1,690 

1,770 

1,780

Sediment 

loads 

(tons)

132

73 

66 

60 

. 76 

48 

49 

51 

58 

84 

71 

58 

67 

58 

' 56 

51 

59 

41 

, 42 

55 

53 

51 

78 

49 

56 

1 172 

114 

5» 

48 

48

. 1,983

Day

1 

2.. .. ... ... ...

3. .__ 

4 . 

5 .... ..

6.. .-'.. 

7 

8. ___ ......

9

10-.- '-

!!-._ -.

12...- .. ... 

13. 

14. 

15 

16. 

17 

18 .

19-. 

20 

21 

22. .

23... . . _

24 

25 

26 

27 

28 

29.. . ..... . ...

30 

31.. .

 Total 

July 1939

Discharge 

(secondfeet)

1,780 

1,740 

1,680 

1,670 

1,610 

1,520 

1,530 

1,540 

1,530 

1,580 

1,630 

1,620 

1,640 

1,650 

1,580 

1,540 

1,570 

1,580 

1,500 

1,510 

1,420 

1,300 

1,240 

1,220 

1,260 

1,270 

1,280 

1,280 

1,250 

1,260 

1,260

Sediment 

loads 

(tons)

58 

47 

36 

36 

48 

53 

41 

33 

25 

34 

35 

44 

44 

31 

26 

25 

34 

38 

36 

33 

35 

25 

27 

26 

27 

31 

28 

21 

27 

20 

34

1.058

August 1939

Discharge 

(secondfeet)

1,250 

1,260 

1,290 

1,280 

1,230 

1,230 

1,220 

1,220 

1,240 

1,320 

1,330 

1,300 

1,340 

1,360 

1,370 

1,360 

1,340 

1,290 

1,210 

1,160 

1,150 

1,170 

1,140 

1,050 

1,100 

1,130 

1,160 

1,340 

1,430 

1,180 

0

Sediment 

loads 

(tons)

51 

20 

28 

14 

10 

23 

16 

16 

17 

21 

22 

21 

14 

18 

15 

37 

25 

28 

26 

22 

22 

25 

25 

20 

27 

24 

16 

14 

19 

13 

0

649

September 1939

Discharge 

(secondfeet)

0 

0 

0 

0 

0 

0 

272 

933 

1,270 

1,230 

1,390 

1, 330 

1,190 

1,250 

1,120 

786 

0 

0 

0 

0 

0 

0 

0 

0 

0 

67 

521 

883 

942 

1,010

Sediment 

loads 

(tons)

0 

0 

0 

0 

0 

0 

9.5 

27 

55 

46 

75 

54 

61 

78 

115 

74 

0 

0 

0 

0 

0 

0 

0 

0 

0, 

1.1 

28 

41 

46 

65

775.6

October 1939

Discharge 

(secondfeet)

920 

0 

0 

0 

0 

0 

0 

0 

0

1 80 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

152 

732 

998 

1,190 

1,370 

1,400 

1,280 

1,180

Sediment 

loads 

(tons)

79 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

12 

59 

84 

145 

141 

155 

97 

76

848
DAILY DISCHARGE AND SEDIMENT LOADS 

NEW YORK CANAL NEAR BARBER, IDAHO Continued

Ill

Day

1.... ____ ..-..--.

"i.. ...... ............

3. _ ................

4.. ________ .....

5....................

6.r 

7.r.. ....... ..........

8....................

9....................

10- - - 

11. .. ................

12...................

13 

U. ...... ... ... ......

U.. .................

l^. ..................

n. .................. i%. ..................

19.. .................

20

21 .. ...

22...................

23 ....

24 _.. 

25 .. .. .

26........ .. ......

27_ 

28 

29..... .....

3D 

31 .................

Total 

November 1939

Discharge 

(secondfeet)

752 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

69 

618 

904 

1,070 

1,090 

1,080 

1,080 

1,130 

1,170 

1,160 

1,140

Sediment 

loads 

(tons)

238 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

15 

135 

173 

144 

106 

79 

87 

171 

126 

53 

80

1,407

December 1939

Discharge 

(secondfeet)

1,130 

1,140 

1,110 

1,110 

1,120 

1,120 

1,130 

1,120 

1,150 

1,180 

1,220 

1,190 

1,180 

1,160 

1,170 

731 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 '0 

0 

0 

0

Sediment 

loads 

(tons)

79 

68 

69 

120 

73 

112 

92 

91 

106 

277 

478 

180 

143 

119 

139 

99 

 0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0

2,245

January 1940

Discharge 

(secondfeet)

0 

0 

0 

83 

147 

158 

92 

0 

0 

37 

79 

, 50 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

. 0 

0 

0 

0 

0 

0 

0 

0 

0

Sediment 

loads 

(tons)

0 

0 

0 

45 

112 

118 

46 

0 

0 

29 

62 

40 

0 

0 

0 

0 

0 

/ 0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0

452

February 1940

Discharge

(secondfeet)

0 

0 

0 

0 

.0 

0 

144 

230 

445 

741 

960 

967 

1,090 

1,150 

1,140 

1;080 

1,100 

1,110 

1,080 

1,090 

1,050 

1,080 

1,060 

904 

922 

1,040 

1,120 

1,100 

1,140

Sediment 

loads 

(tons)

0 

0 

0 

0 

0 

0 

78 

124 

329 

1388 

575 

389 

262 

193 

274 

207 

166 

177 

175 

171 

150 

169 

172 

186 

102 

368 

2,120 

2,700 

2,210

11,685

i Total sediment loads reported on and after Feb. 10,1940.

Discharge and total sediment loads, March to June 1940

Date

l... _ _ _,__ 

2. . ....

3...................

4.. __ , 

5... __ .............

6....... .............

7.......... ..........

8....... .............

9..... ............

10 

11- 

12...... .............

1S^. .................

u_. .................

16.. . ................

W.. .................

17..... ... ...... .....

IS. 

19 

20

21.. 

22...................

23. 

24........... .....

25 ...... ......

26.. . ...

27 

28 

29.. ...

30. 

31- ....

Total..... .....

March 1940

1,020 

819 

699 

611 

624 

750 

816 

1,030 

1,040 

960 

914 

946 

998 

1,050 

1,040 

1,050 

661 

0 

0 

0 

0 

0 

293 

671 

822 

1,260 

1,520 

1,600 

1,480 

1,340 

1,320

i

1,100 

559 

464 

317 

377 

397 

372 

526 

764 

490 

415 

347 

340 

312 

323 

309 

209 

0 

0 

0 

0 

0 

171 

328 

635 

* 2,700 

12,200 

4,030 

2,120 

1,180 

1,270

32,255

April 1940

1,290 

1,370 

1,280 

1,170 

960 

818 

900 

762 

603 

674 

869 

1,060 

988 

928 

984 

1,040 

, 1,200 

1,390 

1,600 

1,810 

2,000 

2,180 

2,320 

2,420 

2,520 

2,580 

2,640 

2,560 

2,320 

2,220

1,930 

1,240 

2,180 

1,300 

632 

314 

301 

193 

166 

206 

291 

544 

494 

398 

361 

309 

337 

 342 

449 

489 

432 

559 

601 

745 

803 

906 

1,080 

968 

802 

569

19,941

May 1940

2,160 

2,180 

2,140 

2,190 

2,320. 

2,420 

2,520 

2,600 

2,640 

2,670 

2,660 

2,680 

2,680 

2,640 

2,640 

2,620 

2,610 

2,580 

2,560 

2,570 

2,560 

2,560 

2,520 

2,520 

' 2,600 

2,62» 

2,630 

2,620 

2,640 

2,660 

2,680

420 

542 

624 

461 

564 

425 

544 

576 

606 

591 

'589 

760 

832 

627 

456 

651 

479 

404 

415 

319 

484 

498 

422 

306 

281 

269 

213 

332 

299 

294 

174

14,457

June 1940

2,700 

2,700 

. 2,700 

2,700 

2,710 

2,710 

2,700 

2,710 

2,400 

2,040 

1,840 

1,900 

2,110 

2,360 

2,180 

1,940 

1,960 

1,960 

1,960 

1,990 

 2,020 

1,980 

1,960 

1,950 

1,960 

2,020 

2,010 

2,000 

1,950 

1,930

233

182 

190 

233 

241 

176 

248 

220 

201 

149 

99 

118 

131 

115 

106 

84 

116 

116 

85 

81 

71 

86 

74 

79 

90 

71 

76 

140 

121 

£3

4,015
112 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

COTTONWOOD GULCH AT BOISE, IDAHO

Discharge and total sediment loads, January 1989 to June 1940

 Day

1. ....... _ .

2... ..........

3 ... -- -

4 L 

6 ... .... 

6 ........ ..

7. .... .... .

8 

9 

10 

11 

12 

13- 

14... .........

15- 

16 

17 

18 . -

19 

20 

21 .. .

22 

23 

24 

25 ... i 

26 

27 

28 

29 

30 

31 

Total -.

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, 

TotalJanuary 1938

Discharge 

(secondfeet)

\

1.3

1.4

 1.6 

1.8 

1:6 

1.5 

.42

 

Sediment 

loads 

(tons)

0.5 

.4 

.3 

.2 

.02

1.42

June 1939

0.67 

.60 

.54 

.54 

.60 

.60 

.60 

.54 

.60 

.54 

.48 

.43 

.38 

.33 

.38 

.54 

.60 

.60 

.60 

.54 

.48 

 .38 

.33 

.33 

.28 

.28 

.19 

.14 

.10 

.10

0.02 

.01 

.006 

.007 

.01 

.01 

.01 

.01 

.02 

.02 

.02 

' .02 

.008 

.007 

.008 

.01 

.01 

.01 

.01 

.009 

.008 

.006 

.004 

.004 

.004 

.004 

.003 

.002 

.002 

.002

0.274

February 1939

Discharge 

(secondfeet)

1.4 

1.4 

1.5 

1.4 

1.6 

1.5 

1.4 

1.4 

1.4 

1.6 

1.6 

1.8 

1.9 

2.5 

3.8 

3.1 

2.4 

2.4* 

2.4 

'2.3 

2.3 

3.5 

3.9 

3.6 

4.6 

3.3 

3.6 

3.6

.........

Sediment 

loads 

(tons)

0.6 

.1 

.1 

.09 

.6 

.2 

.1 

.2 

.5 

.5 

.4 

.7 

.9 

5'. 6 

15 

18 

»8.1 

5.1 

3.5 

3.9 

14 

14 

70 

22 

18 

20 

14 

7.4

243.59

July 1939

0.10 

.10 

.10 

.14 

.14 

.10 

.10 

.10 

.10 

.10 

.05 

.01 

.01 

.01 

.05 

.05 

.05 

.05 

.01 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.10

0.001 

.001 

.001 

.002 

.002 

.002 

.002 

.002 

.002 

.002 

.001 

0 

0 

0 

.001 

.001 

.001 

.001 

0 

.001 

.001 

.001 

.001 

.001 

0 

0 

0 

0 

.001 

.001 

.001

0.030

March 1939

Discharge 

(secondfeet)

2.8 

3.7 

3.5 

3.0 

2.6 

4.6 

4.1 

4.2 

4.6 

6.4 

. 9.8 

23 

22 

15 

14 

17 

26 38- 

51 

51 

51 

45 

43 

40 

37 

26 

27 

24 

23 

20 

18

.........

Sediment 

loads 

(tons)

10 

7.0 

20 

16 

20 

24 

45 

36 

45 

87 

123 

775 

1,040 

773 

515 

591 

900 

1,850 

2,260 

2,440 

2,610 

1,620 

1,160 

1,550 

1,680 

797 

678 

606 

347 

378 

288

23,291.0

August 1939

0.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.10 

.10 

.05 

.05 

.10 

.10 

.10 

.08 

.05 

.10 

.10 

.10 

.10 

.10 

.05 

.04 

.01 

.01 

.01 .05' 

.10 

.10 

.10

0.001 

.001 

.001 

.001 

.001 

0 

0 

0 

0 

0 

0 

0 

.001 

.001 

.001 

.001 

0 

. .001 

.001 

.001 

.001 

. .001 

0 

0 

0 

0 

0 

0 

.001 

.001 

.001

0.017

April 1939

Discharge 

(secondfeet)

16 

15 

14 

12 

11 

10 

9.4 

8.7 

8.0 

7.7 

7.7 

7.3 

6.7 

6.4 

6.1 

5.6 

5.3 

5.1 

4.6 

4.4 

4.4 

4.2 

3.9 

3.9 

3.7 

3.4 

3.0 

2.9 

3.2 

3.2

.........

Sediment 

loads 

(tons)

221 

190 

217 

145 

133 

50 

23 

70 

28 

26 

32 

13 

16 

29 

11 

4.8 

5.9 

11 

5.9 

6.5 

9.6 

3.1 

2 9 

3'. 2 

3.2 

2.2 

1.3 

1.1 

.6 

.9

1, 266. 2

September 1939

- 0.10 

.10 

.10 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.06 

.07 

.05 

.05 

.05 

.05 

.05 

.04 

.04 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05

0.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.009 

.001 

.001 

.001 

.001 

.001 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

.001 

.001

0.028

May 1939

Discharge 

(secondfeet)

2.7 

2.5 

2.4 

2.4 

2.2 

2.2 

2.1 

1.9 

1.8 

1.7 

1.7 

1.5 

1.4 

1.3 

1.3 

1.3 

1.3 

1.3 

1.2 

1.2 

 1.2 

1.2 

1.3 

1.2 

1.0 

.94 

.87 

.73 

.67 

.67 

.67

.........

Sediment 

loads 

(tons)

0.6 

.4 

.3 

.2 

.2 

.2 

.2 

.2 

.2 

.2 

.1 

.1 

.08 

.09 

.1 

.05 

.1 

.1 

.05 

.06 

.05 

.04 

.06 

.07 

.04 

.03 

.05 

.04 

.04 

.03 

.02

4.00

October 1939

0.06 

.06 

, .05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05 

.05

0.001 

.001 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0

0.002,
DAILY DISCHARGE AND SEDIMENT LOADS 

COTTONWOOD GULCH AT BOISE, IDAHO Continued

113

Day

1 _

2.. 

3 ... ...........

4

5- 

6-.. ..............

7 

8. _ _ .. _ .

«..... ......... ...

10 

31- 

12.. .................

13.-

14. ...... ......._....

15.......... .... ...

16--.-...... ...

17-. 

18.. .... .......

19-- 

20 

21 

22 

23 

24 

25 

26 

27 

28.. . 

29... ...

30 

31 

Total 

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 

Total 

November 1939

Discharge 

(secondfeet)

0.05 

.05 

.05 

.05 

.05 

.11 

.13 

.05 

.08 

.11 

.11 

.11 

.11 

.12 

.12 

.12 

.12 

.12 

.13 

.13 

.13 

.15 

.23 

.38 

.40 

.46 

.54 

.57 

.57 

.54

Sediment 

loads 

(tons)

0 '0 

0 

0 

0 

.001 

.001 

0 

0

:ooi

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.001 

.002 

.002 

.002 

.003 

.009 

.002 

.001

0.037

March 1940

23 

20 

19 

16 

15 

13 

12 

12 

12 

12 

11 

11 

10 

9.6 

9.3 

9.3 

, 8.9 

8.6 

8.6 

8.2 

7.9 

7.9 

7.6 

7.3 

8.6 

11 

12 

11 

11 

12 

30

 

676 

774 

488 

364 

178 

87 

82 

65 

53 

44 

48 

39 

27 

11 

15 

5.0 

39 

22 

22 

14 

9.4 

4.8 

3.9 

5.6 

11 

31 

38 

52 

. 46 

74 

1,130

4,458.7''

December 1939

Discharge 

(secondieet)

0.57 

.57 

.57 

.64 

.68 

.68 

.68 

.71 

.87 

.91 

.95 

.91 

.87 

.79 7 r 

!83

^ 

.91 

.95 

.91 

.95 

.91 

.87 

.68 

.68 

. 71 

.75 

.79 

.87 

1.1

Sediment 

loads 

(tons)

0.002 

.002 

.002 

- .002

.002 

.004 

.009 

.006 

.06 

.1 

.1 

.007 

.007 

.006 

.006 

.01 

.02 

.02 

.01 

.01 

.01 

.01 

.01 

.01 

.009 

.009 

.01 

.01 

.01 

.05 

.09

0.613

April 1940

35 

34 

27 

24 

26 

20 

19 

18 

20 

16 

16 

15 

15 

14 

14 

12 

11 

10 

9.3 

8.9 

7.9 

7.3 

6.4 

6.2 

6.2 

6.2 

7.0 

7.9 

7.9 

6.2

1,160 

809 

1,180 

982 

878 

553 

436 . 296 

279 

318 

296 

149 

186 

259 

110 

134 

100 

51 

39 

28 

10 

5.2 

4.8 

4.9 

3.8 

2.6 

3.2 

79 

32 

15

8,403.5

/ January 1940

Discharge 

(secondfeet)

1.6 

2.2 

3.6 

3.4 

2.6 

2.0 

' 1.6 

1.7 

2.3 

2.2 

1.8 

, 1.6 

1.2 

1.4 

1.2 

1.1 

1.1 

.87 

.83 

1.0 

.95 

1.0 

* 1.0 

1.1 

1.1 

2.2 

2.9 

2.4 

2.2 

2.0 

1.9

Sediment 

loads 

(tons)

0.07 

.6 

.3 

.8 

.04 

.03 

.009 

.009 

.4 

.06 

.02 

.04 

.04 

.04 

.04 

.03 

.02 

.02 

.03 

.04 

.04 

.03 

.02 

.02 

.02 

2.5 

.5 

.1 

.1 

.1 

.09

6.158

May 1940

5.2 

4.8 

' 4.6 

4.4 

4.1 

3.9 

3.6 

3.2 

3.0 

2.6 

2.5 

2.4 

2.5 

2.2 

2.3 

2.2 

2.1 

1.9 

1.8 

1.7 

1.6 

1.5 

1.3 

1.2 

1.2 

1:2 

1.2 

1.2 

1.1 

.92 

.84

 

22 

8.8 

7.5 

3.2 

1.0 

1.9 

1.1 

.6 

.4 

.4 

.3 

.2 

.2 

.1 

.1 

.1 

.2 

.1 

.1 

.2 

.2 

.1 

.1 

.08 

.06 

.06 

.06 

.04 

.06 

.05 

.04

49.35

February 1940

Discharge 

(secondfeet)

1.8 

1.8, 

2.0 

2.9 

2.5 

3.7 

4.0 

3.7 

3.6 

4.6 

5.1 

4.4 

4.4 

5.5 

5.1 

4.4 

4.4 

4.6 

4.3 

4.2 

4.1 

5.0 

6.0 

7.0 

11 

15 

26 

34 

31

Sediment 

loads 

(tons)

0.1 

.1 

1.3

.5 

.4 

2.7 

1.0 

.6 

.4 

5.9 

2.0 

.5 

1.0 

7.3 

2.3 

2.1 

2.2 

3.2 

1.7 

13 

4.6 

9.7 

9.7 

18 

64 

96 

291 

673 

884

2,098.3

June 1940

0.84 

.92 

92 

1.2 

1.0 

.94 

.94 

.94 

.76 

.61 

.48 

.35 

.30 

.30 

.22 

.18 

.15 

.13 

.11 

.11 

.10 

.10 

.10 

.09 

.09 

.09 

.09 

.09 

.09 

.09

.. .....

0.04 

.05 

.05 

.05 

.03 

.02 

.02 

.02 

.01 

.005 

.005 

.004 

.003 

.003 

.003 

.002 

.002 

.002 

.001 o

0 

0 

0 

0 

0 

.004 

.004 

.004 

.004 

.004

0.340
SIZE ANALYSES OF SEDIME

Results of size analyses of a large number of samples of suspended 

following tables. A description of the method of analysis is given on page 

Size analyses of suspended sediment

Date ' Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

0

Boise River near Twin Springs. Idaho *

1939

May 18 __ - .-.. 

1940

2, 630

 *

2,690

4 150 '

Point samples 

O.Sft. above 

bottom

A

B,

C

D

Bottom 

A

B

C

D

A

B

C

D

Integrated 

samples

A

B

* C

D

690

279

KO

48

411

3,310

9fl9

63

388

93

96

40

192

152

OKO

530

12.7

5.0

5.3

1.5

15.7

16.7

6.7

3.0

*

15.8

23.5

16.4

8.2
Boise River at Notus, Idaho'

19S9 

Mar. 21... ..............

Mar.25... _ - __ .....

Mar. 30....- __ . __ -

Apr. 4........ ...........

Apr. 8. .. __ . ___ .

194J 

Apr. 1.. ..............

Apr. 5 ...................

Apr. 21 ___ ....... _ .

3:30p. m... ...... .

11:20 a.m.. .....__

6:20'p.m.. ........

4:20 p. m __ _- .._

1:45 p. m ___ ....

1,290

2,930

i,35<r

5,900

3,330

1,170

4,480

4,860

Integrated ' 

samples

B B

A ~ B

C

A

B

C

A

B

C

Point samples 

Surface

A

B

C

Mid-deplh 

A

B

C

0.3ft. above 

bottom

A

B

C

Bottom 

A

B

C

Integrated 

samples

A

B

C

A

B

O

796

1,140

150

158

117

269

408

311

134

186

155

359

417

384

398

422

397

424

595

662

456

3,050

901

665

594

562

315

81

184

26.3

OR O

32.1

36.8

60.3

21.6

13.5

16.1

24.7

20.8

23.7

37.1

33.6

33.2

41.4

38.4

40.9

40.6

1.7

25.6

^4.7

4.6

18.1

15.0

17.9

17.8

4.8

22.0

10.6

32.1

ofl 91

30.7

26.4

14.8

17 Q

28.1

13.6

10.8

25.3

43.8'

44.3

44.6

36.7

35.3

35.2

37.7

5.8

21.0

34.6

5.7

16.5

29.3

23.3

24.6

2.9

8.9

11.3

18.9

1Q 4

9.1

9.9

14.8

18.3

14.0

16.4

20.0

14.1

20.2

13.2

10.9 9.9'

11.6

12.2

10.0

10.9

17.0

6.0

10.4

2.2

5.0

21.2

18.4

17.6

5.9

2.5

8.8

See footnotes at end of table.
Size analyses of suspended sediment Con

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.060 

mm.

Boise River at Notus, Idaho 3 Continued

May 12... -_.

May 23- -- -- 

12:55 p. m.. _ ... 1.580

2,670

2,450

Integrated 

samples

A

B

C

A

B

C

A

B

C

 82

103

71

174

312

209

85

108

124

Cottonwood Creek near Arrpw Rock Reservoir, Id

1940 

Mar. s. .................

Apr. 1 ~~ 

5:10 p. m._ _ !..__ 26

60

28

26

Integrated 

samples

LWS 

LWS

HWS

HWS

LWS

LWS 

HWS

HWS

LWS

LWS 

HWS

HWS

LWS '

LWS

HWS

HWS

3,570 

210

- 165

112

12,800

18, 700 

3,320

4,170

809

589 

120

175

1,380

584

278

455"

0.2 

- 16.1

1.6

10.9

.V

.1 

.1

.1

1.1

0.6 

12.3

15.8

21.8

.5

.3 

1.5

1.2

3.4

0.4 

12.6

28.1

30.3

.6

.4 

2.0

1.7

2.9
SIZE ANALYSES OF SEDIMENTS 117

0 

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Size analyses of suspended sediment Con

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

Q.050 

mm.

Moore Creek above Granite Creek near Idaho City

19S9 

Apr. 2...... ._...-_._

Apr. 13.... ..... 

Apr. 20..................

8:15 a. m ..........

159

113

86

122

Integrated 

samples

Point samples 

Surface

Mid-depth

Bottom

SurfaceMid-depth

Bottom

Surface

Mid-depth 

Composite. ...

281

57

110

1,040

65

66

114

fi4

68

5.4

11.7

4.9

.5

3.5

5.1

2 7

5.5

«.6

7.5

8.5

3.2

.4

2.9

6.1

3.1

2.5

6.2

8.1

8.0

2.6

.3

5.4

12.5

4.4

3.S

8.0
Apr. 28,.......... .... 

May 30 . ....

June 24 .. .

1940 

Apr. 4 ........ __ .....

May 19..................

7 p. m .............

835 a.m.. ........

2:45 p. m------ ... 

10:30 p. m __ .. ...

1:15 p. m.. _ .....

145 

23

17

116 

77 

76

Bottom 

Composite ....

Integrated 

samples

(") 

(>)

Point samples 

Surface

Composite. ...

0.3 ft. above 

bottom

Composite.... 

Bottom 

Composite- ...

Integrated 

samples

m 

«(s) 

(s) 

(6) 

(5)

286

315. 

163

12

12 

14

143 

229 

53 

121 

38 

52

1.6

3.2

7.4

22.9

15.3 

26.5

1.1

7.0 

18.1

19.8

20.6 

22.8

1.6

 9.4 

38.3

17.6

9.9~ 

41.1

Moore Creek above Thorn Creek near Idaho City, 

1939 

Mar. 30... . .... ...

Apr. 3 .. 

Apr. 4................... 

Do ... ............

1:30 p. m ..........

7:10 p.m.... ... 

2 p. m ............. 

7:10 p. m . ....

287 

341 

369 

361

Integrated 

samples

A 

B 

C 

A 

B 

C 

A 

B 

C 

B 

C

211 

242 

229 

339 

.258 

288 

270 

233 

249 

222 

224

62.3 

43.0 

55.3 

43.5 

56.1 

42.6 

 37.3 

45.3 

-40.5 

42.3 

42.0

23.0 

23.8 

21.1 

28.2 

35.3 

44.4 

27.0 

34.3 

37.2 

31.6 

35.2

5.1 

10.4 

6.5 

12.3 

3.2 

6.7 

10.4 

9.1 

5.8 

9.3 

9.0

See footnotes at end of table.
Size analyses of suspended sediment Co

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

Q.020 

mm.

0.020- 

0.050 

mm.

Moore Creek above Thorn Creek near Idaho City, Idaho 

1939

Apr. 7...................

Apr. 13.. .........-..

, Do -.. . .-- .

361

254

200

200

Point samples 

Surface

B

C

Mid depth 

A

-B

C

Bottom 

A

B

C

Integrated 

samples

A

B

C

A

B

C

Point samples 

Surface

A

B

C

Oo«

230

222

233

234

210

282

 255

220

196

181

192

182

176

165

174

171

189

jo 9

48.1

46 4

45.9

38.5

49.6

40.2

42.8

42.3

43.6

42.1

35.2

48.1

44.3

39.5

40.4

32.3

11.8

OO Q

31.1

38.9

31.7

39.4

38.0

25.7

29.3

39.8

30.5

43.7

32.7

36.2

41.0

39.4

47.5

22.4

15.3

7.8

5.1

6.6

5.5

O O

5.1

4.7

" 4 6

5.4

5.0

4.9

5.4

3.4

7:2

 4.0

11.2

28.1
SIZE ANALYSES OF SEDIMENTS 121

OG3C5 COOCO

IN IN '

3 O5 CO CO O »

OOO«O

^aJcj

ONCO

cococi

PH CO CO O5 CO O

iNCOr-! 'O O.-HO

co o

Oi^it ( Oi-l OOO OOO

COt~-O tOOOO

OOO 

COI-HOO

-HIMX5 

ciovoo

<NC*<N

CO 000 

OOO'lO

00"0

co co ?<5

O5 IN 00

OO T I

IN CO CO 

00 tO CD

tOi-HUS -HOOO OJi-ICO COCO>O t^COOO COQi-H

< -^ O5 1> CO * W5CO-*

oeoco oot~-o Or-io

Is
Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

Moore Creek above Thorn Creek near Idaho City, Idaho 

- . ' 

1939 

June 24. __ .. .

July 10- - 

July 21. 

AiK. 2 _________ ..

3:15 p. m ..

11:23 a. m_ .....

j 

3p.m... _

4:10 p.m.. .....

35 

21

13 

10

Surface

A 

B 

C

Bottom

A 

B 

C

Surface

A 

B 

C

Bottom

A 

B 

O

Surface 

A 

Bottom 

A 

B 

C

Surface 

A

956 

990 

564

973 

1,030 

979

939 

489 

499

474 

480 

513

629

554 

605 

626

365

93.1' 

93.0 

96.2

94.5 

93.3 

93.0

92.3 

94.8 

92.1

96.3 

91.0 

89.5

97.2

95.3 

95.4 

95.4

.96.8

6. 2 

6.3 

3.0

4.1 

6.3 

6.0

7.0 

4.0 

3.9

3.1 

7.4 

7.1

2.1

3.4 

3.3 

3,1

2.0

.5 

.6 

.6

.8 

.2

.7

.7 

.8 

3.5

.6 

1.4 

3.2

.3

.9 

.6 

1.2

1.2
Aug. 9.......... ... .

Aug. 18.................

Aug. 25.................

Sept.27._.--.___....

Get. 14..

3:25 p. m____."

4:30 p. m_____

3 p. m .....

9:05 a.m..........

11:10 a. m

.

7.7

6.0

11

15

Bottom 

A

B

' Swfaea 

A

Bottom

B

Surface 

A

Bottom

3

A

Bottom 

A

B

Integrated 

samples

A

B

Point samples 

Surface

A

B.

Bottom 

A

B

O

357

373

047

380

354

385

"398

470

AIR

399

394

454

410

427

403

385

848

85 5

94.9

92.6

89.8

91.2

93.6

fifi R

72.0

95.5

07 7

98.4

ea o

91.7

90 9

92.4

92.9

98. 3

95.1

3.7

3.5

3.6

4.2

4.9

2.5

4.5

A Q

O Q

1.7

1.0

3.7

3 

A.

0 0

o 3

2,2

2.2

.8

.1

J.S

3.1

2.3

1.8

5.0

15.6

1.0

0

.2

g

,2

.4

.8

.1

See footnotes at end of table.
Size analyses of suspended sediment Con

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

Moore Creek above Thorn Creek near Idaho City, Idaho

1939 Nov. 18. . 

Nov. 27.. . ..............

1940 

Jan. 13.... __ ... .... 

-

22

24

25

* 98

^

Integrated samples

A

B

C

A

B

C

Point samplesSurface

A

B

Bottom 

j^

' "n

C

Surface 

A

- Bottom 

A

C

Integrated 

samples

A

C

610

596

641

1,020

984

1,010

844

SQQ

cms

805

809

899

ft Oft

Q74.

930

QA7

1,080

1,160

1.740

96.7

96.4

97.2

93.9

95.3

98.3

94.8

94.5

Q4. fi

96 1

97.1

91.5

91.8

91.5

Q1 fi

" Q1 7

47.5

80.3

73.2

1.4

1.5

1.1

4.8

3.3

1.1

3.2

4.6

4.5

2

0

1.2

5.3

4.1

I 4-l

4.7

4.6

50.6

17.6

6.8

0.4

.7

.4

.6

.3

.2

.6

.4

.4

.5

.6

1.3

.9

1.0

1.1

1.1

":5

.9

.9
Feb. 12.

Feb.-83.

Feb. 27.

Mar. 11.................

1p.m.............

10:30 a.m.........

4:45 p. m......_.

48

35

182

136

See footnotes at end of table.

Point samples 

Surface

A

B

O

Bottom 

A

B

C

Integrated 

Samples

A

B

O

Point samples 

Surface

A

B

O

O.Sft. above 

bottom

A

B

0

Bottom 

A

B

C

Surface 

A

B

O

0.3 ft. above 

bottom

A

B

C

523

518

519

502

549

582

558

551

571

1,510

1,640

1,590

1,710

1,660

1,620

1,730

1,820

1,720

250

226

245

245

226

225

79.6

77.9

81.1

76.8

82.2

70.7

89.9

91.0

89.3

32.9

44.0

43.1

41.8

37.5

" 43.0

41.0

37.5

30.0

72.0

64.5

76.6

74.6

71.6

58.3

16.7

17.6

13.7

18.6

15.0

20.4

6.6

5.1

7.3

38.4

34.5

35.9

34.7

36.7

33.4

33.9

32.2

34.9

17.6

23.7

19.7

14.8

21.7

21.6

1.6

1.8

2.8

1.3

2.3

"5.0

1.6

2.1

.4

17.3

13.4

13.0

11,6

13.3

8.6

12.5

13.2

16.7

6.7

5.1

2.0

"3.2

2.7

7.2
Size analyses of suspended sediment Con

Date Time

/

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050

mm.

Moore Creek above Thorn Creek near Idaho, City, Idah

1959 

Mar.26.. - .:..

Apr. 13... ............

Apr. 21 _ __

Apr. 28 _ . _ ... _ ..

^

TVfav 17

-

2:30 p. m _____

12:15 a. m.. ....

12m...... ___ ..

34ft

. 286

 )KA

247

214

167

x 182

Bottom 

A

B

Integrated 

samples

A

B

0

A

B

O

A

B

O

A

B

O

A

B

0

A

B

0

Point samples 

Surface

A

B

8

Midrdepth 

A

'8

0

254

240

733

742

727

384

376

365

224

220

259

417

332

330

414

423

398

590

633

533

399

389

354

364

371

360

75.6

70.3

30.6

33.0

29.4

43.3

45.1

48.2

47.9

68.4

56.1

50.5

59.2

67.6

69.4

67.6

71.0

63.8

50 1

53.5

56.3

59.2

64.7

57.5

61.5

16.2

19.1

35.5

31.2

36.2

27.9

25.7

24.7

24.4

15.4

28.8

25.1

30.4

22.8

22.3

20.2

20.4

33.3

37.8

46.4

39.6

39. 9"

38.3

38,6

37.4

34.0

6.1

3.7

1*9

17.6

19.3

13.4

I«.5

15.0

9.0

»

Q

8.0

5.1

5.1

6.0

3.5

3.6

6.5

1.5

2.2

2.3

2.6

2.7

.6

2.1

1.9

2.4
May 27...- 

June 18 

11:25 p.m. ... .

7:15 p.m. ....

125, 

46

03 ft. aboee 

bottom

A 

' B 

O

Bottom

A 

B 

O

Integrated 

samples

A 

B 

C 

A 

B 

C

394

388 

385

411 

390 

394

441 

450 

441

772 

769 

772

58.9 

69.7 

59.6

61.1 

69.2 

'58.6,

. 64.9 

64.5 

63.7 

47.3 

44.8 

45,4

38.1 

33.9 

35.1

32.3 

33.9 

34.3

31.1 

30.7 

-32.3 

49.8 

52.3 

52.5

1.9 

4.2 

2.1

2.7 

3.6 

2.2

1.0 

2.3 

1.5 

1.9 

1.0 

1.1

Granite .Creek near Idaho City, Idaho <

19S9 

Mar. 21 - 

Do.... ___ ........ 

DO.............. .

Mar, 27... .. 

Do....... .... ....

DO.. ... ..... ... 

DO.... 

Apr. 4.. 

Do.. 

Do...... .... 

Apr. 6.. - 

Apr. 6. - - ..........

10:10 a. m. ........ 

4:50 p.m.. ........ 

10p.m............ 

9:50 a.m. 

3:15 p. m '.. 

4 p. m _ ......... 

8:15 p.m. 

lla.m... 

4:10 p. m .......... 

7:50 p. m .......... 

8:50 a. m 

7:15 p.m.. ........

4.0 

5.5 

5.0 

6v3

7.0 

7.2 

7.1 

6.3 

6.6 

6.6 

> 6.0 

5.0

Integrated 

samples

LWS" 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS - 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS 

LWS

3,150 

15,600 

13,800 

19,200 

22,800 

11,800 

6,720 

2,630 

4,900 

31,200 

14,700 

12,800 

9,460 

13,700 

-13,000 

4,190 

27,400 

16,400 

2,610 

1,760 

5,070

0.8 

.6 

.5 

.2 

.2 

.7 

1.2 

3.7 

2.0 

.3 

.5 

.4 

.8 

.4 

.6. 

1.2 

.2 

.2 

.7 

1.7 

.2

0.6 

1.2 

.9 

.3 

.2 

1.2 

2.3 

0.2 

2.8 

.3 

.7 

.3 

.4 

.6 

.6 

1.5 

.2 

.2 

1.4 

1.8 

.2

0.5 

1.6

!2 

.2 

1.3 

2.6 

6.6 

2.9 

.4 

.8 

/4 

.5 

.6 

.7 

2.0 

.3 

.2 

1.6 

1.9 

.3

See footnotes at end of table.
Size analyses of suspended sediment Con

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

Granite Creek near Idaho City, Idaho Contin

19S9 

Apr. 30... ___ 

Do.. .............

Do..... .............

Do........... .......

Do. _ .... __ . ....

1940 

Mar. 4 _________

Mar. 12.... ... _

Apr. 12.......... _ .....

Apr. 19...... ______ _

A'pr. 26-. .

May 6. _________

May 16 .................

May 27.... ..... . 

2:45 p.m. .....

4p.m..... . ...

10:10 p. m . .

11:25 a.m... ......

2:45 p. m ..........

5.0

5.0

4.6

3.7

3.5

' 2.8

3.7

5.0

4.3

4.3

3.4

2.5

1.4

Integrated 

samples

LWS 

LWS

LWS

LWS

LWS 

LWS

LWS

LWS

LWS-s 

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

LWS

1,880 

1,110

1,660

3,980

4,060 

3,690

614

KftA

1,220

01 8

542

800

2,980

4,010

56

106

153

677

68

631

29

46

455

19

653

229

3.8

19 ft

7

0

3.2

3.3

3

n

8.7

7.6

3.0 

3.8

3.9 

18.2

1 9 ft

4 Q

5.9 

6.5

11.5

9

«

3.5

5

0

4.6 

17.6

11.7

4

n

5.1 

6.3

9 n

7.5

3.6

4 9

Bannock Creek near Idaho City, Idaho

1940 

Mar. 12. ............. ...

Mar. 27.. ...............

Apr. 12.. ..... ., ...

 "

1.6

11

4.8

Integrated 

samples

... ..do... ..... .

 ..do... 

.....do...... ...

... ..do.... 

. -do.........

132

175

- 32,900

10,900

273

1,800

1Q. 4

17.9

.1

.4

5l.O

22.3

.4

.9

34.2

27.1

.5

1.3

**
May 1.......... ........ 2 p. m ............. 4.8 

3.' 4

.... .do.... 

 do

 TJo

 do

77 

47 

104 

83 -

Pine Creek near Idaho City, Idaho *

19S9 

Mar. 22. ___ . ___ __

Mar. 27........ ......... 

Do . 

Mar. 31.. __ ...... 

Apr. 3. 

Apr. 6.. . 

2:50 p. m ..........

4:25 p. m ___ ...

7:55 p. m .......... 

4:50 p. m .......... 

8:10 p. m .......... 

6:45 p. m ..........

6.8 

11

11 

11 

12 

8.0

Integrated 

samples

LWS 

HWS 

LWSHWS 

HWS 

LWS 

HWS 

HWS 

LWS 

HWS 

HWS 

LWS 

HWS 

HWS 

LWS 

HWS 

HWS

10,300 

2,500 

1,960 

1,850 

1,970 

1,690 

1,800 

1,610 

1,490 

1,060 

1,230 

1,390 

1,320 

1,290 

492 

257 

197

1.7 

7.8 

6.5 

7.4 

7.6 

 5.1 

7.6 

8.2 

^7.2 

7.6 

8.6 

6.9 

6.5 

7.4 

6.2 

10.0 

18.7

3.6 

14.7 

10.4 

14.0 

13.1 

11.0 

11.4 

11.7 

12.7 

17.4 

13.8 

11.4 

13.7 

13.8 

4.2 

10.9 

11.2

5.2 

22.0 

16.3 

21.7 

18.7 

15.5 

14.7 

14.7 

15.4 

20.7 

17.3 

12.7 

17.0 

16.1 

2.4 

4.8 

5.6

Pine Creek above Barry Placer diversion near Idaho 

19^0 

Mar. 11.. ...... ......

Mar. 27 

Apr. 2. . - 

Apr. 12... . 

Apr. 26.. -

May7____ 

May 16. -

7:40 p. m ..........

2 p. m .............

1:50 p. m _ _ . 

3:20 p. m ___ .... 

12m....,. .....

11:10 p.m. .

4.1 

28 

15 

3.4 

1.6 

1.1 

1.5

Inte 

sair

( 

( 

(

.

jrated 

pies

<0 

 )

6) 

6)

6 ) 

6)

")

1,150 

1,480 

73,200 

78,100 

9,700 

6,450 

393 

248 

330 

438 

1,320 

1,280 

3,240

0.6 

.8 

.2 

.3 

9.5 

19.4 

15.8 

1.3 

10.4 

11.0 

1.9

-

1.3 

1.7 

.5 

.9 

21.7 

28.3 

22.9 

3.1 

30.7 

35.0 

3.8

2.1 

' .2.7 

.4 

.8 

12.9 

25.5 

12.3 

12.0 

41.8 

39.1 

2.0

See footnotes at end of table.
Size analyses of suspended sediment Cont

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

Elk Creek near Idaho City, Idaho

19S9 

Mar. 29.. ............

Apr. 2. ... _

Apr. 6.. .. . 

Apr. 13-.. 

Do ..... .... . .....

7:35 p. m ..........

3 p. m... .

3 p. m _ ........

11 a. m ............

-

71

74

 71

47

47

46

Integrated 

samples

A

. B

A

B

A

B

TO(»)

(5)

Point samples 

Surface

A

B

Mid-depth 

A

B

Bottom 

A

B

SuTfuee 

A

B

Mid-depth

A .

B

Bottom 

A

B

631

729

2,140

879

508

469

241

192

303

149

171

299

207

1,130

535

88

75

228

123

519

643

7.0

5.9

3.0

3.8

3.6

4.3

9.5

10.8

6.2

10.7

7.3

6.1

6.3

1.9

3.1

' 7.3

13.4

2.1

S.4

 1.2

1.4

7 Q

8.6

2.6

5.9

4.4

5.8

13,6

12.6

8.0

15.0

12.1

7.7

11.2

2.3

4.8

15.6

21.3

5.8

7.4

2.7

1.0

10:0

7.1

3.4

9.6

5.1

5.6

11.5

12.1

9.2

20.1

17.9

8.8

14.0

2.5

4.7

10.8

15.3

4.3

13.4

2.6

2.7
June 17... ...............

.

June 28 . - 

\

64

14

' 4 O

Integrated 

samples

(«)

(«)

(«)

Potnt samples 

Surface

A

B

0.1 ft. above 

bottom

A

Bottom

A ' B

Surface

AB

0.1 ft. above 

bottom

A

B

' Bottom 

A

B

3

7K

JOK

436

cm

1,420

4

KA()

1,610

3,590

OQ Af\t\

8,360

6,680

8,320

5,960

21,400

72,300

a 

A

3 

A

3

O

i e q

in Q

2.9

8 

A

3.8

.4

21.8

6.3

4.(i

6.8

1.6

.6

7.2

5.8

5.8

20.0

10.4

3.4

1 A A

4 S

.5

51.8

66.2

70.6

fin s

26.0

4.2

9 7

7.4

6.8

10 Q

19 *

3.1

Q q

4.4

.4

17.7

17.6

16.7

IKK

4.4

1.2

Elk Creek above Gold Hill Placer diversion near Idaho 

1940 

Feb. 28 

Mar. 25.. ............ ...

Apr. 18 

Apr. 28 ...............

TWnir 11

May 21.. .............. .

May 31..... .........

1:45 p. in..........

11:15 a.m.. ___ .

11:40 a.m.. _ ....

22

78

71

49

68

42

32

Integrated 

samples

(«)

(6)

(«)

(6)

(»)

(«)

(«)

(«)

w

TO(«)

(«)

(»)

265

189

884

395

56?

^499

125

266

380

272

313

116

44

365

""

See footnotes at end of table.
Size analyses of suspended sediment Co

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

New York Canal near Barber, Idaho »

19119

Apr. 2.. ..............

May 1 ______ . __ ..

,

6:20 p. m ..........

7:30p. m ... ...

1,320

2,800

Point samples

Surface

A

B

0

Mid-depth

A

B

O

Bottom

A

B

O

Surface

A

B

O

Mid-depth

A

B

C

Bottom

A ,

B

O

124

" 120

141

163

148

146

183

202

194

(8)

<8)

0)

(8)

WC8)

(«)

( )-

(8)

41.1

51.8

42.9

38.3

42.0

42.4

37.3

28.5

32.2

32.1

40.5

36.2

31.4

26.1

36.3

16.2

1O A

16.3

22.7

9x1 *)

19.9

21.0

18.6

16.1

16.7

16.1

IQ n

33.8

17.3

19.1

29.5

20.0

18.3

15.6

i O q

8.3

15.9

12.8

15.7

13.8

12.8

16.5

12.3

10.2

9.6

14.1

13.4

11.7

13.2

14.9

10.3

5.1

5.7

6.6
MaySl.................

June 4 ______

6p, m ......

7:60 p. m ..

2,010

1,260

Surface

A 

B 

O

Mid-depth

.A. 

B 

O

1.0ft. above 

bottom

A 

B 

O

Bottom

X

A 

B 

O

Surface

A 

B 

O

Mid-depth

A 

B 

0

0.5ft. above

A 

B 

O

Bottom

A 

B 

O

See footnotes at end-of table.

23

25

30

oo

20

24

m

24

27

18

22

21

19

ifi

20

17

17

22

2fi

1Q

22

20

to

24

65.7

52.2

64.3

H

o

65.5

51.0

48.3

67.1

63.3

53.1

69.1

72.7

50.5

64.8

56.2

55.3

57.7

57.3

52.9

66.1

62.6

33.7

57.1

58.6

9

0

22.1

27.1

OR n

14.2

35.3

23.8

23.4

20.7

16.3

22.8

16.1

28.4

21.6

149

26.6

2U7

28.2

13.8

20.2

19.5

7.1

21.9

21.8

9.8

1.4

6.2

0

3.5

6.8

> 

6.7

8.8

3.3

3.1'

2.4

4.8

9.2

0

.,10.5

8.5

0

, 4.0

6.5

16.8

7.3

* 

7.1

7.6

3.0
Size analyses of suspended sediment Con

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. md

<0.005 

mm.

'0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

New York Canal near Barber, Idaho» Continu

June 13. ......

-

*

1940 

Mar. 2... - -- 

x

1,310

831

Surface 

A

B

C

Mid-depth 

A

B

C

0.5 ft. above 

bottom

A

B

O

Bottom 

A

B

O

Surface 

A

B

C

Midilepth 

*A

Q

0.5ft. above 

bottom

A

B

O

21

24

20

21

27

17

20

21

16

26

24

18

238

293

268

244

245

225

254

247

259

77 O

55.1

92.8

71.7

50.4

90.6

62.5

80.0

86.8

60.3

75.8

84.5

47.6

 43.3

32.0

57.4

56.6

 53.1

51.9

54.8

49.3

8.6

16.7

4.5

* 

12.1

17.8

2.1

24.2

13.0

3.3

27.4

15.8

7.7

36.5

29.1

30.4

25.5

30.5

35.7

33.2

32.4

39.8

2.4

5.8

0

6.5

1.3

3.1

11.7

0

5.5

0

3.8

0

12.0

8.1

«.o

12.9

11.5

9.8

11.9

7.8

7.7
Mar. 9..._______ 8:40 a.m.......... 1.060

Mar. 15................. 9:06 a. m__...... 1,040

A 

B C

Surface A§

Mid-depth

A 

B C

OJft. above 

bottom

A. 0

Bottom

A 

B C

Surface

A B

Mid-depth

A 

B O

0.6 ft. above 

bottom A

B O

Bottom

A 

B 0

m

2§4 m

S!7fi

288

248

281 m

9KW

<mm

2*6

287

278

1«S

129

106

7S

120

97

105

103 m

117

104

55.1

51.5

44 4

46.9

41.4

50.5

53.2

47.1

53.1

53.5

47 Q

80.6

50.4

50.6

72.7

61.5

49.0

63 9

61.4

61.5

62.9

54.6

62.9

67.7

58.7

33.2

33.9

38,4

34.8

37.1

38.6

32.3

40.0

33.7

33.4

37.2

82.6

32.2

34.4

20.1

20.7

31.8

25.1

23.3

22.0

27.0

23.3

20.2

21.1

27.6

10.3

8.7

10.8

11.1

9,4

8.8

8.6

10.8

9.1

11.6

10.1

13.0

10.3

10.6

3.6

5.3

10.5

3.3

5.5

«.5

2.8

10-8

6.7

6.4

3.3

See footnotes at end of table.
Size analyses of suspended sediment Cont

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p. m.)

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

New York Canal near Barber, Idaho 3 Continu

19tO 

Apr. 2...................

Apr. 20. __ . ______ .

8:30 a.m. _ ....... 1,340

"

-

-

1,710

Surface

A

B

O

Mid-depth

A

B

O

0.5 ft. above 

bottom

A

B

O

Bottom 

A

B

O

Surface

Mid-depth

0.5ft. above 

bottom

Composite. ...

Bottom 

Composite. 

261

287

293

296

338

328

341

304

274

319

308

323

53

81

134

171

30.2

25.8

33.4

32,4

32.0

35.0

33.2

32.2

20.1

31.8

32.7

26.6

28.5

16.5

13.3

7.1

37.3

41.3

41.4

38.5

35.8

33.8

34.8

36.7'

43.8

35.3

-31.4

38.9

34.5

22.1

16.0

11.2

27.3

25 2

18.8-

22.3

21.2

23.8

22.1

21.7

24.6

21.2

25.4

22.1

17.0

9.4

6.3

6.5
Apr. 25...... ............

May 1.. _____ .......

May 11. ................

,

 «.

m

3:50 p.m.. __ ...

2,480

2,130

2,620

Surface

Mid-depth

0.5ft. above 

bottom

Bottom

Surface 

Composite- ...

Mid-depth

0.5ft. above 

bottom

Bottom 

Composite ....

Surface

Mid-depth

1.0ft. above 

bottom

Bottom 

Composite ....

56

92

194

296

47

54

150

333

4fl

55

82

204

28.8

18.7

11.5

5.7

38.8

33.1

9.7

2.8

19.4

17.9

10.9

5.4

20.9

15.3

5.7

4.3

25.9

20.6

8.6

3.5

46.5

28.8

23.2

11.9

8.7

7.3

3.3

9 Q '

14.4

9.9

5.7

2.4

9.7

. 21.4

5.6

3.6

See footnotes at end of table.
Size angles of suspended sediment Conti

Date Time

Discharge 

(secondfeet)

Description of 

sample

Sediment 

concentration 

(p. p> m.)

<O.OQ5 

mm.

0.005- 

0.020 

mm.

0.020- 

0.090 

mm.

New York Canal near Barber, Idaho 3 -Continu

1940 May 24 ..

,

-

2,520

-^

Surface

Composite _

Mid-d«pth

Composite. _

0.5ft. above

bottom

Composite- ...

Bottom

Composite. .

20

35

77

218

40.5

29.3

16.2

5.9

28.6

32.3

11.9

«.4

2.3

10.4

1.4

1.5

Cettonwood Gulch at Boise, Idaho <

1939 Mar 30 "*

Mar. 31.. ___ ........

Ar»r 1

1R

18

16

16

16

Integrated 

samples

LWS

LW8

HWS

LWS

LWS

HWS

LWS -

LWS

HWS

LWS

' LWS

HWS HWS

34,100

45,600

5,280

14,400

20,300

3,180

29,500

26,700

1,360

1,020

4,470

673

1,460

_
Apr. 10 ...............

e»

3 Feb. 29 . ..............

to

!5 Mar. 8..................

1

S Mar. 81 ..............

Apr. 8...S __ . .........

j Apr. ill..:;....,........

1-1 I

Apr. 29....... ...........

4:10 p.m.. ........

2:40 p. m ____ .

1:30 p. m ..........

6:30 p. m _____

11

7.7

32

13

62

18

15

8.2

LW8

LWS

HWS

LWS

LWS

HWS

LWS

LWS 

HWS

HWS

LWS

LWS 

HWS

HWS

LWS

LWS

HWS 

HWS 

LWS

LWS 

HWS

HWS

LWS

LWS

HWS

HWS

LWS

LWS

HWS

HWS

21,500

4,320

811

2,420

5,190

110

26, 700

17,300 

2,400

2,790

3,780

7,030 

347

313

9,250

13,200

14,400 

8,970

f)A 7flft

20,000 

615

665

11,900

14,900

634

500

5,630

3,010

183

181

0.7

1.2 

10.0

6.9

.7

.3

7.1

7.3

7.0

5.2

4.8 

7.7 

.2

.2 

9.5

6.1

.3

.3

3.7

4.2

.5

13.5

16.0

1.0

1.3 

12.6

9.5

.5

.3 

6.1

6.7

16.9

12.5

11.3 

17.4 

.4

.4 

12.6

11.6

.5

.2

4.8

4.5

1.3

23.4

28.1

1.0

1.5 

10.5

9 0

.5

.6 

6.2

15.5

21.3

14.1

12.0 

21.6 

.5

.7 

16.7

16.4

.5

.4

9.3

9.3

1.3

2.7

35.0

31.9

' First value reported shows percent finer than upper limit of range indicated; last 

value reported shows percent coarser than lower limit of range indicated.

1 Sampling points A, B, C, and D are approximately one-fifth, two-filths, three-fifths, 

andjour-flfths the distance across the stream.

»Sampling points A, B, and O are approximately one-fourth, one-half, and threefourths the distance across stream.

4 L,WS indicates low-water section; HWS indicates high-water section. Sample 

obtained by lowering bottle through nappe at several points across section.

6 Sample obtained 

* Sample obtained 

' Sampling points 

across stream. 

1 Concentration le
Size analyst of deposited sediment

Sample 

No. i Date Location

Percen

<0.005 

mm.

0.005- 

0.020 

mm.

0.020- 

0.050 

mm.

0.050- 

0.074 

mm.

0.074

0.14

mm

Boise River

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

26

27

28

29

30

4.9

43

44

WSS 

"War Sfi

.....do ........

.....do ........

 ,_do. 

.....do ..---

.....do ........

So

So

5o

... .'do. ..... -

 ..do... ........

.. .. do .. .

..._do ........

 _ilo 

... ~Io .. .

Apr. 16 .......

... ..do... ... .....

.....do . 

Sept. 10.. .-

 do. 

--__do. _ _ ...

near Barber. 

 do... ... 

 do- .... ..... .. ....

 do ..... 

 do 

do .-----..- .. ..

... . do... ........ .. 

 .do -.

at Barber. 

....do .... . 

at Barber. 

 do. _ 

.....do .

-_...do._--.. ... ... 

Notus. 

 do ...

 .do - _ 

near Barber. 

_ _do.-- ............... ......

Springs. 

 do . 

At mouth of Cottonwood Creek..-.

1.6

.2

1.4

.4

15.9

1.1

.1

2.7

.2

41.5

2.4

.5

11.1

.5

28.2

2.7

.2

.4

.1

.2

.2

.6

.8

.2

.1

.2

.2

.1

.1

.1 1

1.4

3.7

9.0

4.6

1.1

.1

1 9 ft

1.1

4.3

1

2

2

 5
45

46

52

S3

64

55

56

57

58

Sept. 23.... ......

do ....

Oct. 8 - 

.....do. .........

Oct. 25- ..

 - do.... 

 do 

... ..do ........

 ..do. .. 

near Barber, 

do

above dam. 

do

.....do ........ -. .-

 do 

.4

1.0

9.8

25.8

3.6

6.4

.2

10.7

245

4.8

3.0

.1

1.5

7.1

18.5

2.7

16.8

.2

4.6

4.0

4.3

2.0

.7

3.5

4.8

12.8

Cotton-wood Creek

36

37

1939 

May 19.. . ....

..... do...... .. . .do 

0.3

.3

0.3

.2

0.1

.2

0.1

.1

Grouse Creek

22

23

61

62

63

64

65

1939 

Apr. 12. ... ..

do

July 27.. 

 do_ ..... ..

..... do .......

..... do .... ...

do

do ...... . .... 

do

. do ... . . ....

do

 do..... ______ ......

1.5

3.2

.8

.3

1.8

0.6

.2

4.2

2.1 j

Q ;

rl*

4.2

.6

8.9

4.4

1.4

9 ^

5.7

6.3

1.2

1.2

1.2

.7

Moore Creek

20

31

32

33

19S9

do. . 

-...do.... 

do .. .

 ... do... ...................... 1.4 2.3 9.5

4.4

4.6

15.5

See footnotes at end of table.
Size analyses of deposited sediment Co

Sample 

No.« Date Location

Perce

<0.005

mm.

0.005- 

0.020 

mm.

0.020- 

0.060 

mm.

0.050 

0.074 

mm.

0.0

0.

nu

Moore Creek Oontinued

47

48

49

50

51

79

19S9 

Sept. 23.. .......

 ..do. .......

.....do ........

..... do..... .

.....do...........

1940

Giant 99

5.9 miles above mouth _ ___ 

0.9

1.5.5*

1.5

0.9

.8

.5

.5

0.6

.1

.2

.2

0.6

.1

.1

.2

1.7

Bannock Creek

18

19

38

39

59

60

1939

June 22 ..........

.....do...........

1940 

Mar. 29 .........

.....do...........

.....do-....... :... .... ...... 

 do 

 do 

.....do. ......... ............ ...

.....do................... .......

"

0.8

1.0

0.5

.6

0.5

1.3

0.6

3.1

.4

.9

1.4

1.4

Elk Creek

34

35

40

41

1939 

Mayl4._ .......

 ..do- -- . 

1.3

.6

.3

.4

1.9

.9

.5

.6

3.5

.6

.9

1.8

9.2

1.2

.8

2.0
New York Canal

21

66

67

68

69

70

71

19S9 

Apr. 10..........

1940 

Sept. 8.. ____

.....do. __ . ....

...-do . .

.....do...........

.....do... .....

..... do...........

1.0 mile below gaging station... _

__ do ____________ : ...

Lateral ditch adjacent to canal 18.4

miles below Diversion Dam.

1.0

1.6

Cottonwood Gulch

24

26

WS9 < Apr. 14..... _£.._ 1.3

1.1

i Numbers correspond to those in the table on pages 62 and 63.

8 For each sample, the first entry shows the percentage of the sample that is finer than the upper limit of the siz

that is coarser than the lower limit indicated.
144 DISCHARGE AND SEDIMENT, BOISE RIVER BASIN

COMPOSITION OF DISSOLVED MATTER IN THE BOISE

RIVER

The chief interest in the Boise River is in its utility in connection 

with irrigation. In addition to difficulties resulting from sediment 

loads carried by the river and irrigation canals in the drainage basin 

there are problems relating to the concentration of dissolved mineral 

matter in the irrigation and return drainage waters. Although not 

so readily recognized, damage to lands and crops from high concentrations of certain salts in some parts of the country is frequently of 

greater significance than damage from clogging of canals and ditches 

with stream sediments.

Investigation of the composition of dissolved matter in the Boise 

River was made in connection with the stream-flow and sedimentmeasuring program. Arrangements were made for the collection of 

daily water samples from the Boise River at Dowling ranch and at 

Notus for the purpose of determining the chemical character of the 

river water at those two points.

The station at Dowling ranch was selected because of its proximity 

to Arrow Rock Reservoir. It is above all important diversions for 

irrigation, and water passing this station is representative of water 

released from the reservoir. Inasmuch as only small releases were 

being made at the time the sampling program was started, it was 

decided to collect samples from the Boise River near Twin Springs 

until larger releases were made from the reservoir. Daily samples 

were collected at this station from January 21 to March 31, 1939. 

Daily samples were collected from the station at Dowling ranch from 

April 1, 1939, to January 17, 1940.

The station at Notus was selected because it is below all diversions 

and below most of the drainage ditches on the Boise project. Water 

passing this station contains practically all of the dissolved matter 

brought in by drains flowing into the Boise River except that which 

may have been removed from the water by the soil. Daily samples 

were collected at Notus from January 13, 1939, to January 17, 1940.

Chemical analyses were made in the laboratory of the Water 

Resources Branch of the Geological Survey in Washington on 10-day 

composites of daily samples. The results of these analyses, together 

with the loads of dissolved matter given for each station, are tabulated 

at the end of this section. The last column of the table is labeled 

"percent sodium." The percent sodium of a water is the ratio, 

multiplied by 100, of the equivalents per million of sodium to the sum 

of the equivalents per million of calcium, magnesium, sodium, and 

potassium.
DISSOLVED MATTER IN THE BOISE RIVER 145

According to Scofield,7

The significance of this characteristic of the salt complex in irrigation water 

lies in the results of reactions of base exchange on the physical properties of the 

soil. If the dissolved salts are preponderantly those of calcium and magnesium, 

i. e., if the percent sodium is low, then the reactions of base exchange are in the 

direction of maintaining good tilth and good permeability in the soil. On the 

other hand if the percentage of sodium is high the consequent reactions of base 

exchange in the soil tend in the direction of the replacement of calcium and magnesium by sodium in the exchange complex with the result that the soil becomes 

deflocculated and impermeable to water. Experience indicates that if the 

sodium percentage is below 50 there is little danger of impairing seriously the 

physical condition of the soil. If it is above 60, such danger exists. The critical 

ratio is believed to lie between 50 and 60.

The water passing the Twin Springs and Dowling ranch stations is 

low in dissolved matter, is soft, and the percent sodium is well under 

the critical limit suggested by Scofield. The concentration of dissolved solids ranged from about 50 to 100 parts per million, the total 

hardness from about 30 to 60 parts per million, and the percent of 

sodium from about 20 to 35.

The composition of the water passing the station at Notus is characterized by larger amounts of dissolved matter and is more variable 

than the water passing the upper stations. The concentrations of 

dissolved solids ranged from about 120 to 900 parts per million, total 

hardness from about 60 to 280 parts per million, and percent sodium 

from about 30 to 60. Changes in composition resulted in part from 

variations in the amount of water released from Arrow Rock Reservoir, 

the amount of water diverted for irrigation, and the amount of drainage return water discharged into the river. The effect of these variables on the composition of the water is different at different seasons 

of the year.

Based on Scofield's classification, water released from Arrow Rock 

Reservoir is suitable for practically all types of agriculture and will, 

with proper drainage, have little tendency to impair the physical 

condition of the soil. Water passing the station at Notus sometimes 

has a higher percent sodium than is generally recommended for 

agricultural use.

The general increase in dissolved mineral salts in the lower reaches of 

the Boise River is due largely to the discharge of concentrated drainage 

waters. With each succeeding diversion of the river water for irrigation, and it may be reused several times, there is usually a corresponding increase hi dissolved mineral salts. It seems probable, 

however, that with adequate drainage and with sufficient flow in the 

Boise River to dilute the more concentrated drainage water, the quality 

of the water in the river is suitable for practically all agricultural 

purposes.

7 Scofield, C. S., South coastal basin investigation, quality of irrigation waters: California Dept. of Public 

Works Bull. 40,1933.
Analyses of water from the Boise River, 1

[W. M. Noble and J. D. Hem, analysts. Analytical results in parts per 

Date of collection

Mean 

discharge 

(secondfeet)

Specific 

conductance 

(KXIO* 

at 25° C.)

Silica 

(Si02)

Calcium 

(Oa)

Magnesium 

(Mg)

Sodium 

and potassium 

(Na+K)

Bicarbonate 

(HC03)

Sulfate 

(SOi)

Chlo

(01

Boise River near Twin Springs, Idaho

19S9 

Jan. 21, 23-31. ...... .

Feb. 1-10...... .....

Feb. 11, 13, 15-19. 

Feb. 20-28..... .... ..

Mar. 1-10...........

Mar. 11-20..........

Mar. 21-31......... .

350 

340 

350 

392 

362 

610 

1,776

11 

10 

9.9 

9.7 

9.8 

9.3 

7.6

21

19

12 

12 

12 

12 

12 

12 

9.8

1.4 

1.3 

1.3 

1.3 

1.3 

1.3 

1.2

7 

6 

7 

5 

6 

5 

3

54 

50 

52 

50 

52 

48 

38

5.0 

5.8 

4.8 

4.7 

4.5 

4.2 

3.0

Boise River at Bowling ranch near Arrow Rock, I

1939 

Apr. 1-10.. ....... ..

Apr. 11-20...........

Apr. 21-30...........

May 1-10.. .........

May 11-20.. ..... ...

May 21-31.. ..... ...

July 1-10... ........ .

July 11-20... ........

July 21-29.... ...... .

Aug. 2-10...........

Aug. 11-20.. ........

Aug. 21-31....... ....

Sept. 1-10.. .........

Sept. 11-15, 17-20. 

Sept. 21-30... .......

Oct. l-10-...u ..

Oct. 11-20.. ........ .

Oct. 21-31........ ...

Nov. 1-10.. 

Nov. 11-20. -

Nov. 21-30.. 

4,580 

3,741 

4,342 

6,330 

4,969 

3, 556 

2,992 

2,696 

2,889 

2,882 

2,671 

t242 

287 

2,127 

1,935 

970 

1,342 

798 

534 

500 

869 

55.4 

32.5 

1.033

10 

9.4 

9.0 

8.0 

6.7 

6.8 

7.6 

7.3 

6.7 

6.7 

6.8 

7.3

9.2 

9.2 

9.3 

10.1 

10.4 

10.8 

11.2 

10.8 

12.8 

13.5 

11.0

14 

15 

13 

14 

13 

13 

15 

14 

14

10

11

13

12 

12 

11 

10 

9.0 

9.2 

10 

9.4 

8.8 

9.4 

9.3 

10 

11 

12 

11 

12 

12 

13 

14 

14 

14 

15 

17 

14

1.9 

2.0 

2.1 

1.4 

1.1 

1.2 

1.3 

1.4 

1.2 

1.2 

1.2 

1.3 

1.4 

1.4 

1.5 

1.5 

1.6 

1.7 

1.8 

1.8 

1.7 

2.1 

2.4 

1.7

5 

4 

4 

5 

3 

3 

4 

4 

3 

4 

4 

5 

5.2 

4.9 

5.5 

6.6 

7.4 

6.9 

7.4 

7.1 

6.6 

12 

8.8 

8.7

52 

50 

47 

44 

37 

38 

42 

40 

36 

40 

41 

44 

47 

50 

49 

54 

56 

58 

62 

61 

60 

77 

76 

64

4.3 

3.8 

3.9 

3.3 

2.4 

2.6 

2.6 

3.2 

2.7 

2.9 

2.9 

3.2 

3.0 

3.3 

3.6 

4.4 

4.6 

4.8 

5.3 

5.4 

5.0 

6.5 

5.6 

6.1
DISSOLVED MATTER IN THE BOISE RIVER 147

CM COCO

»-4 rtJ

r-IOCO CO-*

"ooooi * to

O i>. corCOOOO t-rH

oo' to' od t> 06

COOOCO COrH 

r-t i-J IN « CO

o

< r-eo >or-

«o coco

§ § § a a 

PPQ ^^

IO CO CO CO *O 5 i 1 r"H CO » 1 1- CO N

r-rr^ C4 *- ( ^

33SS£S3S88S9|;fe88S38833£89S8SS$S898 9§

O (N ^' «0 * >0 >0 «0

tdiotdc^td io<N-*<Ncor-i-*iococooitpoico>o>o» lOoicooicoiooocococo IN co 

eo eo eo eo co * eo 1-1 «>o i-irHoot»oo*eSOr-(5>ocoeo-*>oeoeoeoeoeoeo coco

sn^t? 59^i^i Qpiaiot^iorH^^iSSSSS^!:! 53^9 StRrrfriStrPS^ CO 3S

I>O-* r-C*

K^cof^t-cocSScoFi«c^SoHS55eo?iei5cO!COoBtS>i>F;fif-;tifif;fii>- coS

IN t~ CO CO 00 * 00 CO * OO
INDEX

Page

Abstract,.______________.._____ 1-2 

Arrow Rock, mean monthly temperatures at- 8 

precipitation at-________. _____ 7,9 

Bannock Creek near Idaho City, description

of gaging station on_ ______ 79 

discharge and sediment loads of-____ 99-100 

size analyses of suspended sediment

from............................ 128-129

Bed load, variation in._______... 54-62; pi. 9 

Boise, mean monthly temperatures at- ___ & 

precipitation at__ __.____. 7,9 

Boise River, at Notus, chemical analyses of

dissolved matter from.. __. __ 147 

at Notus, description of gaging station on. 76 

discharge and sediment loads of -_ 86-87 

size analyses of suspended sediment

from........................... 115-116

near Arrow Rock, chemical analyses of

dissolved matter from.. ___ - 146-147 

description of gaging station on___. 77 

discharge and sediment loads of...._ 84-85

near Twin Springs, chemical analyses of

dissolved matter from-...__.. 146 

description of gaging station on___ 76 

discharge and sediment loads of_ _ 82-83 

size analyses of suspended sediment

from................__.......... 114

Climate of the area________.__..._ 5-10 

Cottonwood Creek, near Arrow Rock Reservoir, description of gaging station 

on...._______________.. 77

near Arrow Rock Reservoir, discharge

and sediment loads of-..___ _ 88-89 

size analyses of suspended sediment

from............................ 116-117

Cottonwood Gulch, at Boise, description of

gaging station on _ _______ _ 81 

at Boise, discharge and sediment loads

of.. .......................... 112-113

size analyses of suspended sediment

from............................ 138-139

Cross sections of channel, variations in.-----. 71-75

Deposited sediment, above Diversion Dam,

source of...____ 66-69; pis. 10,11,12 

size analyses of suspended sediment

from......................... 64,140-148

specific gravity of samples of- ______ 64,66 

weight-volume relation of- __ __ _ _ 62-63

Discharge, record of mean daily.--_____ 82-113 

Dissolved matter in Boise River, composition

of ............................ 144-147

Diversions, placer, discharge of-. 94,103-104,107-108 

Diversions from the Boise River, records of. 19 

Elk Creek, above Gold Hill Placer diversion,

description of gaging station on_ 80 

above Gold Hill Placer diversion, discharge and sediment loads of..... 109

Elk Creek Continued

size analyses of suspended sediment

from..________________ 113 

near Idaho City, description of gaging

station on..___________.. 80 

discharge and sediment loads of-_ 105-106 

size analyses, of suspended sefliment

from............................ 130-131

Gaging stations, description of- ________ 76-81 

Geography of the area..-_________ 3-4; pi. 1 

Granite Creek, near Idaho City, description of

gaging station on..._.....___ 78

near Idaho City, discharge and sediment

loads of________. ______ 97-98 

size analyses of suspended sediment

from............................ 127-128

Grouse Creek, near Arrow Rock, description

of gaging station on____ A- 77 

near Arrow Rock, discharge and-sediment

loads of-______________ 90-91 

size analyses of suspended sediment

from ........................... 117

Idaho City, mean monthly temperatures at- - 8 

precipitation at_ -__-____----- 6.9

Irrigated areas, location of----___.____ li

Moore Creek, above Granite Creek, description of gaging station on. _____ 78 

above Granite Creek, discharge and

sediment loads of . .. 92-93 

size analyses of suspended sediment

from 118-119

above Thorn Creek, description of gaging

station on---- -- 78

discharge and sediment loads of _ 95-96 

size analyses of suspended sediment

from 119-127

New York Canal, near Barber, bed load

in ---------------------- 54-60; pi. 9

near Barber, description of gaging station

on- . 81

discharge and sediment loads of- . 110-111 

size analyses of suspended sediment

from 132-138 

velocities and sediment concentrations

at various depths in. - ___ 43-53 

Pine Creek, above Barry Placer diversion,

description of gaging station on__. 79 

above Barry Placer diversion, discharge

and sediment loads of __ _ __ 102 

size analyses of suspended sediment

from_-_-______________ 129 

near Idaho City, description of gaging

station on.-- _______.... 79

discharge and- sediment lands of. . 101-102 

size analyses of suspended sediment

from-._....... _._ - 129

149
150 INDEX

Page

Placer-mining areas, location of-_______ 12-13

Precipitation, records of- -_________... 6,7,9

Reservoirs in the area_____ ____ 11-12; pi. 2

Runoff, comparison of_____________ 16-19

discharge of.-.._______________ 19

measurement of-_________ 14-16; pis. 3,4

Runoff and sediment-load measurements,

areas selected for_________ 14 

Sediment samples, determination of sediment

concentration of._________ 24 

determination of size composition of. -__ 24-25 

equipment for collecting.---.__ 20-22; pis. 5,6 

frequency of collecting_____. _____ 23 

sampling procedure for collecting. ____ 22-23 

Size analyses of sediment, measurements of. 114-143

Page

Sluicing of Arrow Rock Reservoir.. ... 69-71 

Stream gradients in the area . ________ 11 

Stream beds, mean elevation of________ 72-75 

Suspended sediment, at 13 stations, measurement of. -.---.___._-__ 37-43 

basis of reporting----__________-. 27

computation of__________ __... 25-27

definitions of terms concerning 19-20

record of daily loads of___________ 76-83,

95-102,105-106,109-113

relation of to total loads... ________ 30 

reliability of reports on. ____ -. 28-30 

size analyses of............. 38-41,52-53,114-143

Temperatures, records of..________ 8,9,10 

Topography and drainage in the area . 4-5

o