UNITED STATES DEPARTMENT OF THE INTERIOR 

J. A. Krug, Secretary

GEOLOGICAL SURVEY 

W. E. Wrather, Director

Water-Supply Paper 998

SUSPENDED SEDIMENT IN

THE COLORADO RIVER

1925-41

BY

C. S. HOWARD

UNITED STATES

GOVERNMENT PRINTING OFFICE 

WASHINGTON : 1947

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

Price 45 cents

CONTENTS

	Page 

Abstract __---___---_-__----__----_ _______ ____ 1

Introduction. .. ________________________________ ______ 1

Collection of samples_____________..-______________ __ ___- _ 2

Colorado River sampler_-___-_____--________________ __ _ 2

Types of samples collected ________________ _ _______ 4

Individual samples_______________________________________ 4

Integrated samples_____-___-_-___-_____-__-__-__----___ _ 4

Frequency of sampling________________.________________-_______ 5

Size samples.---__----------_--_---_-__--_-__-_----_---_--_- 5

Determination of suspended sediment ______________________________ 5

Determinations__-____--____-__-_________._____-___-_-___-__ 5

Weighing the samples_____ ______________________________ 5

Weighing the sediment-_-__--_________-_____-_____--____--_ 5

Computations_______________________________________________ 5

Concentrations --- -_____-_-____----__-----_ _-----__-_ 5

Loads__________________________________________________ 6

Daily loads_______-______--_--_--_-_____---_---____--_ 6

Monthly loads____ __ __-_ _-- ___---_ ---__-_-__ 6

Annual loads______________________ _________________ 6

Daily sediment records____-______-_-____--______-_-_-_-________ 6

Mean daily concentrations_ - __________ _-__________ 6

Suspended sediment in individual samples.___________________ 7

Annual, maximum, and minimum daily loads _____________________ 8

Sources of loads measured at Grand Canyon station________________ 10

Physical nature of suspended and deposited sediment ________ _ _______ 11

Methods of determination of particle size.________________________ 11

Suspended sediment.__________________________________________ 13

Bank deposits_______________________________________________ 13

Reservoir deposits___________ __________________________________ 13

Determined quantities of suspended sediment_________________________ 14

Index_________.._______.____._____..________________ 165

ILLUSTRATIONS

PLATE 1. Geological Survey Colorado River sampler____-___-__-_____ 10

2. Line of demarcation of inflow and water of Lake Mead approximately 90 miles above Boulder Dam______________________ 18

3. Deposit in slack-water area about 97 miles above Boulder Dam_ 18 

FIGURE 1. Map of the Colorado River drainage basin showing sedimentsampling stations______________________.____________ 3

m
IV CONTENTS

TABLES

Page

TABLE 1. Maximum and minimum daily loads of suspended sediment 

at gaging stations on Colorado, Green, and San Juan Rivers, 

October 1, 1925, to September 30, 1941____________ 8

2. Suspended sediment and runoff of Colorado River at gaging 

station near Yuma, Ariz., October 1, 1925, to September 30, 

1941___________________________________________ 10

3. Load of suspended sediment and runoff at Cisco, Green River, 

and Bluff gaging stations in comparison with Grand Canyon 

station______________________________________________ 10

4. Kind of information and periods covered by the tables of data

for 8 gaging stations____._______________________________ 15

5. Mean daily concentration of suspended sediment in the Colorado

River near Cisco, Utah, May 14, 1929, to September 30, 1939_ 16

6. Mean daily discharge, mean daily concentration, and daily load 

of suspended sediment in the Colorado River near Cisco, Utah, 

October 1, 1939, to September 30, 1941____________ 21

7. Mean daily concentration of suspended sediment in the Colorado 

River at Lees Ferry, Ariz., October 1, 1928, to December 16, 

1933________________.__-____._____. .___________-___. 25

8. Mean daily concentration of suspended sediment in the Colorado 

River near Grand Canyon, Ariz., October 1, 1925, to September 30, 1929_______________._____--__-----__--____-_- 28

9. Mean daily discharge, mean daily concentration, and daily load 

of suspended sediment in the Colorado River near Grand 

Canyon, Ariz., October 1, 1929, to September 30, 1941____ 30

10. Suspended-sediment concentration in individual samples collected from the Colorado River near 'Grand Canyon, Ariz., 

April 1, 1935, to September 30, 1936______________ 54

11. Mean daily discharge, mean daily concentration, and daily load 

of suspended sediment in the Colorado River near Willow 

Beach, Ariz., October 1, 1934, to September 30, 1936___. 83

12. Mean daily concentration of suspended sediment in the Colorado 

River near Topock, Ariz., October 1, 1925, to September 30, 

1934_____.___________________________________________ 87

13. Mean daily discharge, mean daily concentration, and daily load 

of suspended sediment in the Colorado River near Topock, 

Ariz., October 1, 1934, to March 31, 1939__ _ _________ 92

14. Mean daily concentration of suspended sediment in the Green 

River near Green River, Utah, May 1, 1929, to September 30, 

1939-________.______________- _____-_---_--_----_--- 101

15. Mean daily discharge, mean daily concentration, and daily load 

of suspended sediment in the Green River near Green River, 

Utah, October 1, 1939, to September 30, 1941_________ 106

16. Suspended-sediment concentration at different sampling times, 

mean daily discharge, mean daily concentration, and daily load 

of suspended sediment in San Juan River near Bluff, Utah, 

August 13 to September 21, 1928______ 110
CONTENTS V

Page

TABLE 17. Suspended-sediment concentration at different sampling times, 

mean daily discharge, mean daily concentration, and daily 

load of suspended sediment in the San Juan River near Bluff, 

Utah, July 1 to September 30, 1929_______________ 113

18. Mean daily discharge, mean daily concentration, and daily load 

of suspended sediment in the San Juan River near Bluff, Utah, 

October 1, 1929, to September 30, 1941____________ 117

19. Suspended-sediment concentration in individual samples collected from the San Juan River near Bluff, Utah, in September 

and October 1937, September 1939, July to October 1940, and 

March, April, and September 1941_______________________ 141

20. Suspended-sediment concentration at different sampling times, 

mean daily discharge, mean daily concentration, and daily 

load of suspended sediment in Little Colorado River at Grand 

Falls, Ariz., July 6 to September 26, 1931 ______ _ ___ 144

21. Velocity and suspended-sediment concentration of water in the 

Colorado River near Grand Canyon, Ariz., April 6 to July 24, 

1935.__________--.___.__________________ 146

22. Velocity and suspended-sediment concentration of water in the

Colorado River near Topock, Ariz., April 3 to June 29, 1935__ 148

23. Mechanical analyses of suspended sediment in samples collected 

in the Colorado River near Grand Canyon, Ariz., April 5, 

1935, to September 30, 1941____________________ 150

24. Mechanical analyses of suspended sediment in samples collected 

in the Colorado River near Willow Beach, Ariz., April 2, 1935, 

to September 27, 1936__._____.___.________ 159

25. Mechanical analyses of suspended sediment in samples collected 

in the San Juan River near Bluff, Utah, May 3, 1935, to 

September 30, 1936__ _ __. __________________ 161

SUSPENDED SEDIMENT IN THE 

COLORADO RIVER

1925-41

By C. S. HOWARD

ABSTRACT

This report gives the results of sediment-sampling studies of the Geological 

Survey in the Colorado River basin for the period from October 1, 1925, to 

September 30, 1941. Records are given for the entire period for the Grand 

Canyon gaging station and for shorter periods at other stations in the basin. 

The results reported consist of the records of the mean daily concentrations.of 

sediment for all stations, and in addition, the mean daily discharge and daily 

load of sediment for many of the stations.

The available records indicate that the runoff of the Colorado near Cisco, 

Utah, plus the runoff of the Green at Green River, Utah, plus the runoff of the 

San Juan near Bluff, Utah, amount to about 90 percent of the runoff at the 

Grand Canyon gaging station, but the sediment loads at the three upper stations 

amount to only about 60 percent of the sediment load at Grand Canyon. The 

Little Colorado River and two or three other unsampled tributaries probably 

are the major sources of the unmeasured sediment.

Information is given concerning the sizes of the particles of the sediment at 

the Grand Canyon, Willow Beach, and Bluff stations during periods of this 

investigation.

The annual load at Grand Canyon during the 16 years ranged from 50,080,000 

tons in 1933-34 to 480,000,000 tons in 1928-29, and the mean annual load at 

that station for the 16-year period was 200,200,000 tons. The mean annual 

runoff for the Grand Canyon station during the period was 12,640,000 acre-feet

INTRODUCTION

For the 16-year period, October 1, 1925, to September 30, 1941, 

sampling programs were carried on at the gaging station on the Colorado River near Grand Canyon, Ariz., and for shorter periods at 

other stations on the main river and its principal tributaries. The 

sampling points were at gaging stations for which records of discharge 

were being obtained and at which engineers were available for the 

collection of samples and the determination of the quantity of sediment in the individual samples.

Records of discharge were made available by A. B. Purton, Salt 

Lake City, Utah, and W. E. Dickinson and John H. Gardiner, Tuc1
2 SEDIMENT IN COLORADO RIVER, 1925-41

son, Ariz., district engineers of the Geological Survey. The samples 

were collected by members of the staffs of those district offices. The 

computations of daily and annual loads were made by the personnel 

of the Water Resources Laboratory of the Geological Survey.

The field work and preparation of this report were under the supervision of W. D. Collins, Chemist in Charge, Quality of Water Division, 

Water Resources Branch of the Geological Survey.

The data presented in this report cover the entire period for which 

a comprehensive sediment-sampling program was carried on in the 

Colorado River Basin. The results obtained in the continuation of 

this program are prepared annually for presentation in the series of 

reports entitled "Quality of surface waters of the United States."

COLLECTION OF SAMPLES

Sediment samples were collected as a continuing project during 

the periods indicated at the following stations:

Colorado River near Cisco, Utah, May 14, 1929, to September 30, 1941.

Colorado River at Lees Ferry, Ariz., October 1, 1929, to December

16, 1933. 

Colorado River near Grand Canyon, Ariz., October 1, 1925, to September

30, 1941. 

Colorado River near Willow Beach, Ariz., October 1, 1934 to September

30, 1939.

Colorado River near Topock, Ariz., October 1, 1925, to March 31, 1939. 

Green River at Green River, Utah, May 1, 1929, to September 30, 1941. 

San Juan River near Bluff, Utah, August 13 ^fco September 21, t928; July

1 to September 30, 1941. 

little Colorado River at Grand Falls, Ariz., July 6 to September 26, 1931.

The locations of these stations are shown on the map of the Colorado River drainage basin, figure 1.

COLORADO RIVER SAMPLER

The samples were collected by means of the sampler shown in plate 1. 

This sampler, designed by Carl H. Au, hydraulic engineer of the 

Geological Survey and described in a previous publication, 1 was designed 

to be attached to the cable in place of the current meter used for 

discharge measurements and was made so that suitable weights 

could be added to the bottom of the sampler.

The first samplers were made to puncture a paper covering a %- 

inch hole in an ordinary milk-bottle cap, but the samplers were modified so that a stopper could be pulled out of a rubber cap that had 

been fitted to a regular pint milk bottle in place of the ordinary milkbottle cap.

i Howard, C. S., Suspended matter in the Colorado River in 1925-28: U. S. Geol. Survey Water Supply 

Paper 636, pp. 18-19,1930.
COLLECTION OF SAMPLES

FIGURE 1. Map of the Colorado River drainage basin showing sediment-sampling stations.
4 SEDIMENT IN COLORADO RIVER, 1925-41 

TYPES OF SAMPLES COLLECTED

INDIVIDUAL SAMPLES

During the early part of the investigation "bottom," "surface," 

and "average" ("integrated") samples were collected. The bottom 

samples were collected by lowering the bottle to the bottom, opening 

the bottle, and allowing it to stay there for a time long enough to be 

filled, after which it was raised rapidly. The average, or integrated, 

samples were obtained by allowing the bottle to become nearly full as 

it was being lowered and raised, or, under some conditions, only 

during the raising. The detailed results obtained on the different 

types of samples are given in an earlier paper. 2

INTEGRATED SAMPLES

The method of collecting average, or integrated, samples used in 

this study is the "depth-integration method" described in a report of 

the United States Engineers.3

Throughout this investigation average samples were used for the 

computation of the mean concentration for each day. During the 

first 3 years the average sample was collected by lowering the empty 

bottle to the bottom, opening the bottle, and raising it at such a rate 

that the bottle was full when it reached the surface. During the 

remainder of the investigation the average sample was taken by 

lowering to the bottom a bottle with an open hole in the cap and 

raising it at such a rate that it would not be quite full when it returned 

to the surface. At some river stages it was not possible to lower and 

raise the bottle fast enough to get a partially filled bottle and it was 

necessary to use the bottle-opening device, At times when the river 

was carrying fine drift, such as grass, needles, and the like, it was not 

possible to operate the bottle-opening device and integrated samples 

were obtained by lowering the bottle with the open hole in the cap 

to such a depth that it could be lowered and raised before the bottle 

became full. It has been shown 4 that there is an initial inrush of 

water into the bottle when it is opened at the bottom, and an undue 

proportion of the sample comes from the greatest depth. As a result 

of this inrush the samples collected in this manner are not representative for the entire depth, but no data are available to show the magnitude of the error in samples collected from the Colorado River by this 

method.

2 Howard,FC. S., op. cit., pp. 29^0.

3 U. S. Engineer Office, St. Paul, Minn., A study of methods used in measurement and analysis of sediment loads in streams, Report 1, Field practice and equipment used in sampling suspended sediment, 

pp. 72-74,1940.

* U. S. Engineer Office, St. Paul, Minn., A study of methods used in measurement and analyis of sediment loads in streams: Report 1, Field practice and equipment used in sampling suspended sediment, 

pp. 72-74, 1940; Report 3, Analytical study of methods of sampling suspended sediment loads in streams, 

pp. 57-60,1941; Report 5, Laboratory investigation of suspended sediment samplers, pp. 88-91,1941.
DETERMINATION OF SUSPENDED SEDIMENT 5

FREQUENCY OF SAMPLING

At each gaging station a set of integrated samples was collected at 

three points in the cross section. It was planned to have one set of 

samples collected each day during periods of normal stage and two or 

more sets each day during periods of flood stage. It was not possible 

to carry out this daily sampling program at all stations, and for 

several periods the records are incomplete.

SIZE SAMPLES

Additional samples for the determinations of the sizes of the particles 

of the suspended sediment were collected approximately twice each 

week at the Grand Canyon station during the period from April 1, 

1935, to September 30, 1941. For part of this period similar samples 

were collected at the Willow Beach and Bluff gaging stations.

DETERMINATION OF SUSPENDED SEDIMENT

DETERMINATIONS

Most of the determinations of the quantities of suspended sediment 

were made at the field stations. The original records were sent to the 

laboratory in Washington for review and further computations.

WEIGHING THE SAMPLES

For the period October 1, 1925, to March 31, 1930, the weight of 

each sample was considered to be 473 grams, but after March 31, 

1930, each sample was weighed and that weight used in computing 

the concentration of sediment.

WEIGHING THE SEDIMENT

The weight of sediment in most of the samples was determined by 

filtering the samples through weighed filter papers, which were then 

dried and reweighed. Corrections for the moisture content of the 

filter papers were made by weighing a check paper at the time of the 

original and the final weighings.

The sediment in samples collected at Grand Canyon after October 

1, 1940, was determined by transferring the sediment with as little 

of the original water as possible to a weighed evaporating dish and 

weighing the dried sediment.

COMPUTATIONS

CONCENTRATIONS

The sediment concentrations were computed for each sample and 

reported in percent by weight of the samples as collected. The mean 

concentration was computed from the individual results, usually as 

the average of the individual determinations, but sometimes one or
6 SEDIMENT IN COLORADO RIVER, 1925-41

more of the individual determinations were obviously not representative for the day and therefore were not considered in computing the 

mean concentration for the day. During flood periods when sufficient 

samples had been collected, the mean concentration for the day was 

computed by considering the mean concentration for each set of 

samples and the rate of discharge for the part of the day for which 

those samples were considered representative.

LOADS

Loads of suspended sediment were reported as tons per day, tons 

per year, and for some stations for which sufficient records were available as tons per month. No effort was made to compute the volume 

of the sediment carried in any period.

Daily loads. The daily loads of sediment were computed from the 

mean concentration for the day and the mean daily discharge by the 

following equation:

Daily load (in tons)=mean concentration (percent by 

weight Xmean daily discharge (in second-feet)X27.

The mean concentration of sediment was estimated for some of the 

days for which records were not available and the daily loads computed 

from these estimated values. , Monthly loads. Monthly loads were computed as the sum of the 

daily loads for months for which data were available for all the days. 

These loads, where computed, are listed in the tables giving the daily 

loads of sediment.

Annual loads. The annual loads of suspended sediment were 

computed as the sum of the monthly loads for those stations for which 

there were sufficient data for the computation of the monthly loads. 

If monthly loads were not computed the annual load was computed 

from the weighted-average concentration of all the samples collected 

during the year and the total discharge for the year. The weightedaverage concentration was computed by multiplying the mean daily 

concentration by the mean daily discharge for each day for which 

samples were available and dividing the sum of those products by the 

sum of the mean discharge values for the same days.

The annual loads at stations for which sufficient records are available 

for computation of such loads are given in table 1.

DAILY SEDIMENT RECORDS

MEAN DAILY CONCENTRATIONS

The mean daily concentrations of sediment are given in tables 5 to 

18 for all days for which sufficient records were available. For some 

days on which samples were not collected a concentration value was
DETERMINATION OF SUSPENDED SEDIMENT 7

estimated. In addition to the mean daily concentration values, the 

mean daily discharge and daily load of sediment are given for certain 

periods for most of the stations.

These tables show the variation in concentration and load of sediment from day to day. The highest concentrations in the main river 

occurred at the Grand Canyon station, and the highest concentrations 

in the tributaries occurred at the Bluff station on the San Juan River.

The records for the Willow Beach, Topock, and Yuma stations 

from 1935 to 1939 are of interest in showing the changes in concentration and load that occurred at those stations after the closing of 

Boulder Dam on February 1, 1935. After that date water released 

at Boulder Dam was clear, except for periods of density flows, 6 and 

the suspended sediment represented sediment picked up in the 10- 

mije stretch between Boulder Dam and the Willow Beach station and 

in the 105-mile stretch between the Willow Beach and Topock stations. 

After the closing of the dam the sediment concentration at Willow 

Beach and Topock showed a decrease, and at the end of the sampling 

periods at those stations the water was practically clear.

SUSPENDED SEDIMENT IN INDIVIDUAL SAMPLES

Records for the Grand Canyon and Topock gaging stations for the 

period 1925-28 6 showed the concentrations for the individual samples. 

Similar records are given in the present report for the Grand Canyon 

station for the period April 1, 1935, to September 30, 1936, and for 

the Bluff station during periods in 1937, 1939, 1940, and 1941. The 

records obtained during the 16 years of observations show considerable 

variation in sediment concentration throughout the cross section and 

at certain times throughout the day. The greatest variations in 

concentration were found during the periods of rapid rise that usually 

occurred after heavy rains on the desert part of the watershed.

Results of some observations of sediment concentration and corresponding water velocity at the Grand Canyon and Topock stations 

are given in tables 21 to 22. The data show no conclusive relationship 

between sediment concentration and velocity.

A study of the available records shows no direct relation between 

concentration and discharge. As a rule, the concentration of sediment 

increased with an increase in discharge, but the concentration of 

sediment carried seemed to depend more on the source of the increase 

in flow than on the quantity of the increase.

«Grover, N. C., and Howard, C. S., The passage of turbid water through Lake Mead: Am. Soc. Civil Eng. 

Trails., vol. 103, pp. 722-723, 1938. 

6 Howard, C. S., U. S. Geol. Survey Water Supply Paper 636, pp. 29-40,1930.
8 SEDIMENT IN COLORADO RIVER, 1925-41

ANNUAL, MAXIMUM, AND MINIMUM DAILY LOADS

The annual, maximum, and minimum daily loads computed from 

the data for 1925-41 are given in table 1 for the Cisco, Lees Ferry, 

Grand Canyon, Willow Beach, and Topock stations on the main 

river; for the Green River, Utah, station on the Green River; and for 

the Bluff station on the San Juan. The data in this table indicate 

that the highest daily loads in the main stream occurred at the Grand 

Canyon station and that the highest daily loads in the tributaries 

occurred at the Bluff station on the San Juan.

TABLE 1. Maximum and minimum daily loads of suspended sediment at the Cisco, 

Lees Ferry, Grand Canyon, Willow Beach, Topock, Green River, and Bluff stations 

for the period Oct. 1, 1925, to Sept. SO, 1941

Colorado River near Cisco, Utah

Water year ended 

Sept. 30

1930 «... __ .......

1931 « 

1932.. .............

1933- _ ..........

1934. ___ .... _ .

1935-- __ ... __ -

1936 

1937- __ ... ... .

1938 

1939 - _ 

1940 

1941 

Annual 

runoff 

(acre-feet)

6,090,000 

2, 860, 000 

6, 680, 000 

4, 640, 000 

2, 220, 000

4, 681, 000 

5, 765, 000 

4, 621, 000 

7, 422, 000 

4, 252, 000

3, 463, 000 

6,576,000

Annual load 

of suspended 

sediment 

(tons)

18, 600, 000 

9, 910, 000 

26, 400, 000 

8, 190, 000 

2, 720, 000

17, 8407000 

17, 180, 000 

23, 560, 000 

35, 700, 000 

14, 470, 000

9, 900, 000 

32, 200, 000

Day of maximum load

Mean 

discharge 

(secondfeet)

11, 700 

11,200 

28,440 

28,600 

15,500

9,360 

9,070 

12,910 

37,400 

5,320

9,430 

40,500

Suspended sediment

Percent i

3.00 

5.03 

.72 

.42 

.33

1.86 

3.75 

4.67 

.87 

2.85

2.91 

1.12

Load 

(tons)

947, 000 

1, 520, 000 

767, 000 

324, 000 

138, 000

470, 000 

918, 000 

1, 630, 000 

879, 000 

409, 000

741, 000 

1, 225, 000

Day of minimum l6ad

Mean 

discharge 

(secondfeet)

1,740

787

1,720 

2,300 

1,180 

1,930 

960

1,670 

2,010

Suspended sediment

Percent i

6.03 

.00

.01

.01 

.004 

.02 

.02 

.02

.01 

.01

Load 

(tons)

1,400

216

459 

243 

637 

1,040 

518

451 

543

Colorado River near Lees Ferry, Ariz.

1929- 

1930.. _ .......

1931.- 

1932.. _ .......

1933 

19, 200, 000

13, 100, 000

6, 380, 000

15, 300, 000

9, 730, 000

352, 000, 000

195, 000, 000

57, 200, 000

214, 000, 000

112, 000, 000

65,500

41, 600

9,810

49, 500

79, 900

5.35

8.02

5.51

6.27

1.09

9, 450, 000

9, 000, 000

1, 460, 000

8, 370, 000

2, 350, 000

3,770

4,700

2,780

4,000

4,500

0.09

.15

.13

.17

.08

8,980

19, 000

9,740

18, 300

9,710

Colorado River near Grand Canyon, Ariz.

1926 > _ -

1927- 

1928.. .............

1930..- _ 

1931 - 

1932 

1933 

1934. 

1935 

1936 

1937 

1938-. _ ..........

1939- __ ... 

1941... ............

14, 400, 000

17, 300, 000

15, 600, 000

19, 400, 000

13, 400, 000

6, 720, 000

16,000,000

10, 000, 000

4, 656, 000

10, 216, 000

12, 322, 000

12, 410, 000

15, 630, 000

9, 618, 000

7, 435, 100

16, 940, 000

225, 000, 000

398, 000, 000

172, 000, 000

480, 000, 000

235, 400, 000

68, 810, 000

261, 400, 000

178, 100, 000

50, 080, 000

122, 300, 000

157, 600, 000

191, 300, 000

232, 400, 000

86, 320, 000

270, 100, 000

64, 700

74, 000

65, 400

59, 300

54, 800

31, 300

49, 800

15,200

8,570

101, 400

21, 500

43, 700

39, 100

28,000

13, 300

76, 800

3.02

13.1

2.58

10.9

10.7

1.83

7.49

9.06

11.5

1.01

7.74

2.95

8.76

2.12

4.96

2.92

5, 260, 000

27, 600, 000

4, 550, 000

17, 400, 000

15, 800, 000

1, 540, 000

10, 100, 000

3, 710, 000

2, 660, 000

2, 770, 000

4, 490, 000

3, 480, 000

9, 250, 000

1, 600, 000

1, 781, 000

6, 050, 000

5,320

3,530

4,610

3,190

5,610

4,400

2,160

3,240

4,370

2,830

3,280

2,520

4,580

3,550

2,660

9,380

0.05

.04

.03

.01

.03

.03

.05

.03

.07

.09

.05

.03

.07

.01

.04

.07

7,17C

3,80C

3.72C

86S

4,53C

3,56(

2,91(

2.60C

8.26C

6,89C

4,43(

2.04C

8,66(

95$

2,87C

17,73(

See footnotes at end of table.
DETERMINATION OF SUSPENDED SEDIMENT 9

TABLE 1. Maximum and minimum daily loads of suspended sediment at the Cisco, 

Lees Ferry, Grand Canyon, Willow Beach, Topock, Green River, and Bluff stations 

for the period Oct. 1, 1925, to Sept. 30, 1941 Continued

Colorado River near Willow Beach, Ariz.

Water year ended 

Sept. 30

1935... ............

1936...............

1937-.. .........

1938--.-.-.-. ....

1939--.-----...-...

Annual 

runoff 

(acre-feet)

5, 556, 000 

6, 282, 000 

5, 826, 000 

6,168,000 

8, 473, 000

Annual load 

of suspended 

sediment 

(tons)

13, 890, 000 

6, 830, 000 

358,000 

451, 000

Day of maximum load

Mean 

discharge 

(secondfeet)

6,760 

9,680 

11, 000 

6,160 

26, 000

Suspended sediment

Percent i

2.12 

2.16 

.02 

.23 

.07

Load 

(tons)

387,000 

565, 000 

5,940 

38, 300 

49, 100

Day of minimum load

Mean 

discharge 

(secondfeet)

152 

9,500

Suspended sediment

Percent '

0.02 

.001

Load 

(tons)

81 

256

Colorado River near Topock, Ariz.

1926*... .. .....

1927....... ....

1928-.. .-.

1929- 

1930-- 

1931... 

1932 __ _____

1933... ..... . ..

1934-.... __________

1935- 

1936- 

1937- 

1938 ...... _

1939 «.. .-

14, 300, 000

17, 000, 000

15, 400, 000

18, 900, 000

6, 770, 000

16, 100, 000

10, 200, 000

4, 870, 000

5, 225, 000

6, 025, 000

5, 577, 000

5, 967, 000

8, 188, 400

140, 000, 000

345, 000, 000

209, 000, 000

437, 000, 000

64, 700, 000

272, 000, 000

121, 400, 000

61, 000, 000

27, 800, 000

20, 100, 000

10, 700, 000

9, 710, 000

17,900

96,500

66,100

52, 700

42,200

28,500

32, 600

68, 200

9,750

6,100

9,320

9,080

12, 700

26,600

3.56

7.91

3.01

5.46

6.71

.94

6.50

1.18

4.27

2.64

2.34

.25

.24

.31

1, 720, 000

20, 600, 000

5, 370, 000

7, 760, 000

7, 640, 000

723,000

5,710,000

2, 170, 000

1,124,000

435, 000

589, 000*

61, 300

82,300

222, 600

6,490

4,200

5,490

8,080

4,220

3,820

3,150

3,590

1,750

422

4,700

8,520

5,560

5,600

0.19

.15

.26

1.08

.26

.28

.36

.22

.06

.02

.11

.06

.08

.001

20,800

17,000

38,500

23,500

29,600

28,900

30, 600

21,300

2,840

227

13,960

13,800

12, 000

151

See footnotes at end of table.

Green River at Green River, Utah

1930*-.-- .......

19312..... 

1932... ........... .

1933- 

1934... ............

1935 __________ ...

1936.-... ..........

1937- 

1938- 

1939- 

1940-. 

1941--......- . ...

4, 560, 090

2, 390, 000

4, 810, 000

1, 306, 000

2, 850, 000

4, 147, 000

4, 134, 000

4, 747, 000

2, 376, 000

4, 242, 000

34, 500, 000

7, 450, 000

36, 100, 000

15, 360, 000

1, 780, 000

M, 3PO, 000

33, 800, 000

43, 400, 000

38, 200, 000

8, 880, 000

31, 900, 000

17, 800

12, 300

31,000

7,720

1,480

17 800

13,000

18, 400

9,140

15, 800

2,660

25, 500

3.10

.76

.81

3.42

.83

6.36

. 3.29

5.68

2.02

4.38

2.01

1,490,000

252, 000

677, 000

471, 000

136, 700

399, 000

2, 230, 000

1, 630, 000

1,400,000

862,000

315, 000

1, 384, 000

2,580

978

580

1,140

520

752

969

1,040

830

1,450

664

0.08

.01

.01

.01

.01

.01

.005

.02

.03

.01

.02

5,570

270

162

297

140

216

135

562

672

392

359

San Juan River near Bluff, Utah

1928 6 .... .......

1928 7 . -----

1930- 

1931-.... ..........

1932- 

1933- 

1934- 

1935 .-. __ -.

1936... ...___. ....

1937... .

1938___ ........

1939 . __ . ....

1940..... .......

1941- 

1, 730, 000

3,110,000

1, 720, 000

2, 950, 000

1, 240, 000

661, 900

2, 183, 000

1, 631, 000

2, 336, 000

2, 466, 000

1, 239, 000

996, 300

4, 242, 000

1, 490, 000

100, 500, 000

58, 300, 000

15, 290, 000

75, 300, 000

23, 610, 000

21, 170, 000

42, 700, 000

32, 600, 000

52, 200, 000

52, 100, 000

21, 410, 000

26, 300, 000

112, 700, 000

669

20, 000

13, 900

3,480

9,160

5,960

4,920

12, 500

3,950

10, 200

14, 000

11, 000

12, 130

25,200

8.73

21.2

23.0

9.64

11.3

13.2

20.3

8.72

21.4

13.3

14.2

20.9

12.1

2.02

158,000

11, 450, 000

8, 620, 000

905, 000

2, 790, 000

2, 120, 000

2, 700, 000

2, 940, 000

2, 282, 000

2,840,000

5, 370, 000

6, 207, 000

411

1,680

229

113

145

26

150

469

400

204

118

664

0.24

.54

.11

.01

.09

' .04

.003

.06

.02

.09

.03

.09

2,660

2,449

679

27

351

27

11

756

216

496

96

1,614

1 Percent by weight. Value reported is usually the average of three or more integrated samples

2 Incomplete records. « Oct. 1, 1938, to Apr. 7, 1939. 

8 Oct 12, 1925, to Sept. 27, 1926. « Aug. 13, to Sept. 21, 1928. 

4 Oct. 3, 1925, to Sept. 30, 1926. ' July 1, to Sept. 30, 1929.
10 SEDIMENT IN COLORADO RIVER, 1925-41

The annual loads of sediment at the Yuma gaging station for the 

same period have been computed from the records of the Bureau of 

Reclamation and are given in table 2.

TABLE 2. Suspended sediment and runoff of the Colorado River at gaging station 

near Yuma, Ariz., Oct. 1, 1925, to Sept. 30, 1941

' Water year ended 

Sept. 30

1926..... .............. ..

1927.... 

1928. .... ................

1929............ ............

1930....... ... ... ___.

1931

1932- . .....................

1933 ........ ...

1934_. ......................

1935----..---.----.. 

1936 .__._ _ ...

1937... .. .. .. 

1938..... ...... .........

1939.... ... 

1940....... _. _

1941.- _- .

Suspended 

sediment 

(tons) i

152, 000, 000

241, 000, 000

128, 000, 000

262, 000, 000

180, 000, 000

42, 300, 000

198, 200, 000

89, 000, 000

27, 400, 000

16, 860, 000

17, 600, 000

15, 090, 000

13, 870, 000

11,100,000

5, 067, 000

14,740,000

Runoff 

(acre-feet)

13, 300, 000

16, 000, 000

13, 900, 000

17, 800, 000

12, 500, 000

4, 920, 000

14, 300, 000

8, 070, 000

2, 916, 000

3, 259, 000

3, 803, 000

3, 823, 000

4, 076, 000

5, 828, 000

5, 323, 000

9, 030, 000

1 Records furnished by Bureau of Reclamation.

The mean annual load of suspended sediment at the Grand Canyon 

station during the years 1925-41 was 200,200,000 tons and the mean 

annual runoff at the station during the same period was 12,640,000 

acre-feet.

SOURCES OF LOADS MEASURED AT GRAND CANYON STATION

Records for the Grand Canyon gaging station represent the flow 

and sediment load of the Colorado River above Boulder Dam and 

Lake Mead, the reservoir behind Boulder Dam.

Approximately 90 percent of the runoff measured at the Grand 

Canyon station can be accounted for by the runoff measured at the 

Cisco, Green River, and Bluff gaging stations. The combined annual 

sediment load for those three stations, however, is less than twothirds of the annual load carried past the Grand Canyon station. 

(See table 3.)

TABLE 3. Load of suspended sediment and runoff at Cisco, Green River, and Bluff 

gaging stations in comparison with Grand Canyon station

. [Expressed in percent of load and runoff at Grand Canyon gaging station]

1932 

1935 

1938 

1941 

Cisco

Suspended 

sediment

10 

15 

15 

12

Runoff

42 

46 

47 

39

Green River

Suspended 

sediment

14 

12 

16 

12

Runoff

30 

28 

30 

25

Bluff

Suspended 

sediment

29 

35 

22 

42

Runoff

18 

21 

16 

25

Unmeasured

Suspended 

sediment

47 

38 

47 

34

Runoff

10

5 

7 

11

Grand Canyon

Suspended 

sediment

100 

100 

100 

100

Runoff

100 

100 

100 

100
GEOLOGICAL SURVEY WATER-SUPPLY PAPEE 998 PLATE 1

GEOLOGICAL SURVEY COLORADO RIVER SAMPLER.

PHYSICAL NATURE OF SEDIMENT . H

For the four yearly periods covered by the data in table 3 the 

ratio of sediment to runoff was much higher for the Bluff station 

than for the Green River and Cisco stations. The data in this table 

also show that a large part of the suspended load at Grand Canyon 

came from sources from which samples were not collected. It seems, 

therefore, that an appreciable part of the suspended load carried 

past the Grand Canyon station was brought into the Colorado River 

by relatively small flows of very muddy water. It is likely that 

considerable quantities of sediment were brought into the Colorado 

River from the San Rafael and Fremont Rivers, and it is known 

that large quantities of sediment were brought in by the Little 

Colorado River.

An indication of the quantities brought in by the Little Colorado 

River during the 5 years ended September 30, 1934, can be obtained 

by comparing the records in table 1 for the Lees Ferry and Grand 

Canyon stations for those years, as the Little Colorado flows into 

the Colorado between those stations. -In those 5 years the average 

annual increase in load of suspended sediment between the Lees 

Ferry and Grand Canyon stations was more than 59,000,000 tons. 

Paria River flows into the Colorado just below the Lees Ferry station 

and at times brings in considerable quantities of sediment. It should 

also be pointed out that during 3 of those years the annual loads 

for the Grand Canyon station were higher than the average load 

for the 16 years of observations.

PHYSICAL NATURE OF THE SUSPENDED AND DEPOSITED

SEDIMENT

The physical nature of the suspended sediment, particularly the 

particle size, is the determining factor as to where the various particles 

will be deposited along the banks in eddies and quiet water and in 

reservoirs. For the determination of the particle size of suspended 

and deposited sediments, samples were collected at different places 

in the basin. A few samples were collected to determine the weight 

per unit volume of the deposited material, but the records are not 

complete enough for a statement of the average weight per unit 

volume of sediment.

METHODS OF DETERMINATION OF PARTICLE SIZE

The size of the particles was determined by a method adapted 

from the usual methods for such determinations 7 and consisted of a 

combination of sieving and decantation methods. The procedure

7 U. S. Engineer Office, St. Paul, Minn. A study of methods used in measurement and analysis of sediment loads in streams, Report 4, Methods of analyzing sediment samples, pp. 175-179,1941.

725606 47 2
12 SEDIMENT IN COLORADO RIVER, 1925-41

used with most of the samples provided for no dispersion of the suspended sediment and complete dispersion of samples of deposited 

sediment. The degree of dispersion in the suspended-sediment 

samples varied with the concentration and character of the dissolved 

solids in the water in which the sediment was being carried, and an 

attempt was made to use in the determinations water similar in 

character and concentration to the original water.

The procedure for suspended-sediment samples consisted in pouring 

the sample through a 100-mesh sieve and then through a 200-mesh 

sieve to get the quantities of particles with diameters of 0.149 and 

0.074 millimeter, respectively. If the quantity on the 100-mesh sieve 

was large the material was transferred to a 50-mesh sieve, and the 

quantity held on that sieve (0.297 millimeter in diameter) was determined. The material that passed the 200-mesh sieve was washed into 

a cylinder and the quantities of small particles determined by settling. 

It was customary to determine the quantities of material with settling 

velocities corresponding to 0.050, 0.020, and in some cases 0.005 millimeter. For the determinations by settling, the temperature of the 

suspension in the cylinder was observed and the suspension well 

shaken. The cylinder was then set upright for a time sufficient for 

all the material of a given size to have fallen from the top of the liquid 

to the bottom of the cylinder under the existing temperature conditions. At the end of the correct settling time the liquid was decanted, 

leaving the size group at the bottom of the cylinder. The suspension 

was again shaken and allowed to stand the necessary time for 'the 

settling of the next size group. After decantation of the suspension, 

determinations of other size groups were made as desired -by settling 

and subsequent decantations. This method of decantation gave results that represent all the material of the maximum size and 

quantities of the smaller sizes that were near enough the bottom to 

settle there|in the required time. It seems likely, however, that the 

results of these determinations will be of value in estimating the rates 

of settling of the material carried in suspension.

Samples of deposited sediment wer6 usually dry at the time the 

analysis was made, and it was necessary to disperse them before the 

analysis was started. A part of the sample was weighed out and 

placed in a conical vessel together with a small volume (4 milliliters) 

of 1.5 percent sodium-oxalate solution and about 150 milliliters of 

water. Air was bubbled through the liquid for about 3 hours with 

the orifice of the air tube at the bottom of the vessel. The sizes of 

the particles were then determined by the sieving-decantation method, 

except that distilled water was used for washing the material on the 

sieves and as additional water for the settling medium.
PHYSICAL NATURE OF SEDIMENT 13 

SUSPENDED SEDIMENT

The results of the determinations of the size of the particles of the 

suspended sediment samples are given in tables 23 to 25. As a rule 

most of the material in those samples was found to consist of particles 

with settling diameters of greater "than 0.020 millimeter, but in only a 

few samples was there as much as 10 percent of the material coarse 

enough to be held on the 100-mesh sieve (0.149 millimeter in diameter). 

After the closing of Boulder Dam some of the suspended sediment at 

the Willow Beach station apparently was carried through the entire 

length of Lake Mead,8 and that material consisted of particles whose 

diameters were less than 0.020 millimeter.

BANK DEPOSITS

Throughout the entire basin, deposits of sediment may be found 

along the banks of the river and its tributaries. These deposits usually 

represent the material that is first dropped out of suspension and that 

consists of the larger particles of the suspended sediment. Samples 

have been collected from some of these bank deposits and determinations made of the weight-volume relation of the material in the deposits 

and also of the size of the particles in the deposits. These deposits 

usually had a weight of more than 80 pounds per cubic foot of -dry 

deposit, and the particles have effective settling diameters of greater 

than 0.020 millimeter. Considerable quantities of the material 

carried by the Colorado River, particularly during periods of summer 

floods, consist of particles whose settling diameters are less 'than 

0.020 millimeter, and considerable quantities of the material had 

settling diameters of less than 0.002 millimeter. A weight greater 

than 80 pounds per cubic foot of deposit probably is not representative for all of the suspended material carried in the Colorado River 

Basin.

RESERVOIR DEPOSITS

Little has been reported on the extent and nature of the deposits 

of sediment in reservoirs in the Colorado River Basin. Studies by 

the Bureau of Reclamation on Lake Mead have included observations 

both on the nature of the inflow at the head of the lake and on the 

formation of deposits along the edge and at the bottom of the reservoir.

On a number of occasions it has been observed that the incoming 

water was very turbid and that there was a sharp line of demarcation 

between the incoming water and the lake water. Plate 2 shows such 

an inflow approximately 90 miles above Boulder Dam in January 

1939. Observations taken just below the line of demarcation show

> Grover, N. C. and Howard, C. S., op. cit., pp. 727-728.
14 SEDIMENT IN COLORADO RIVER, 1925-41

that the incoming water, because of it's greater density, dips under 

the surface of the lake water and travels beneath the surface for 

considerable distances without complete mixing. This stratified flow 

in Lake Mead has been discussed by Bell.9

Observations on Lake Mead made from time to time by th,e Bureau of 

Keclamation have shown large deposits of material in places of slack 

water such as or the inside of curves and across inlets of side washes 

and streams. One of the deposits found on March 17, 1939, at mile 

257, approximately 97 miles above Boulder Dam, in an area where 

there was slack water at a sharp bend is shown in plate 3. In addition, observations have shown considerable deposits at points throughout the upper end of the lake. In 1941, the deposits in-Virgin Canyon, 50 miles above Boulder Dam, were more than 30 feet deep, and 

at the intake towers, just above the dam, it was possible to sink a 10- 

pound weight a vertical distance of about 80 feet into the deposits of 

unconsolidated material at the bottom of the reservoir. 10

DETERMINED QUANTITIES OF SUSPENDED SEDIMENT

The quantities of sediment in samples collected in the Colorado 

Kiver Basin by the Geological Survey during the period 1925-41 are 

presented in this report. For selected periods the quantities in the 

individual samples collected at the Grand Canyon and Bluff gaging 

stations are given; for other periods only the mean daily concentrations are tabulated; for some periods the mean daily discharge and 

mean concentration of sediment and the daily load of sediment are 

given. These data are presented in tables 5 to 20. A key to these 

tables is given in table 4.

' Bell, H. S. Stratified flow in reservoirs and its use in prevention of silting. U. S. Dept. Agr. Misc. 

Pub. 491,1942. 

10 Eecords of the Bureau of Reclamation, U. S. Dept. of the Interior.
QUANTITIES OF SUSPENDED SEDIMENT 15

TABLE 4. Kind of information and periods covered by the tables of data for 8 gaging

stations

Gaging station

Colorado River:

At Lees Ferry, Ariz. _ 

Near Grand Canyon, 

Ariz. 

Near Willow Beach, 

Ariz. 

Near Topock, Ariz..--. 

Green River at Green 

River, Utah. 

San Juan River near Bluff, 

Utah.

Gaging station

Colorado River near Grand 

Canyon, Ariz. 

San Juan River near Bluff, 

Utah. 

Little Colorado River at 

Grand Falls, Ariz.

Mean daily concentration of suspended sediment

Period

May 14, 1929, to Sept. 30, 

1939. 

Oct. 1, 1928, to Dec. 16, 1933_

Oct. 1, 1925, to Sept. 30, 1929.

Oct. 1, 1925, to Sept. 30, 1934. 

May 1, 1929, to Sept. 30, 1939-

Table 

No.

5

7 

8

12 

14

Suspended-sediment concentration 

in individual samplesPeriod

Apr. 1, 1935, to Sept. 30, 1936-

Nonconsecutive periods in 

1937, 1939, 1940, and 1941.

Table 

No.

10 

19

Mean daily discharge, mean daily 

concentration, and daily load of 

suspended sediment

Period

Oct. 1, 1939, to Sept. 30, 1941_

Oct. 1, 1929, to Sept. 30, 1941_ 

Oct. 1, 1934, to Sept. 30, 1936-

Oct. 1, 1934, to Mar. 31, 1939. 

Oct. 1, 1939, to Sept. 30, 1941_

Oct. 1, 1929, to Sept. 30, 1941-

Table 

No.

6

9 

11

13 

15

18

Suspended-sediment concentration at 

differing sampling time, mean daily 

discharge, mean daily concentration, 

and daily load of suspended sediment

Period

Aug 13 to Sept. 21, 1928 

July. 1 to Sept. 30, 1922..... 

July 6 to Sept. 26, 1931 -_-.--

Table 

No.

16 

17 

20

Results of special studies at the Grand Canyon and Topock stations 

showing the velocity at the time of sampling are given in tables 21 

and 22. Data on the size of the particles carried are presented as 

follows: Colorado River at Grand Canyon station, April 5, 1935, 

to September 30, 1941, in table 23; Colorado River near Willow 

Beach, April 2, 1935, to September 27, 1936, in table 24; and San 

Juan River near Bluff, May 3, 1935, to September 30, 1936, in table 

25.
16 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 5. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Cisco, Utah, May 14, 1929, to Sept. SO, 1939

1929-30

Day

1

?,

3

4_ 

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

?fl

21

22. 

?3

?,4

25

26

7,7

28

29

30

31

October

November

December

JanuaryFebruary March *

.

April

-

May

0.06

.12

.13

.10

.19

.19

.14

.06

.16

.17

.22

.34

.32

.22

June

0.18

.17

.12

.16

.14

.09

.09

.14

.10

.06

.06 .05"

.20

.14

.08

.13

.12

.05

.04

.10

.07

.04

.04

.04

.05

.08

.05

.03

.03

.02

July

0.03

.03

.03

.02

.04

.06

.04

.02

.03

.15

.15

1.24

.42

1.24

.21

.13

.35

32

.37

.45

.39

.20

.20

.08

.06

.06

.07

.16

.26

.28

August

0.62

.52

1.50

1.53

.42

.50

1.44

3.00

2.69

2.60

1.40

1.91

2.31

1.06

.96

.54

.32

.28

.19

.13

.12

.14

.08

.06

.08

.05

.04

.05

.04

.04

September

0.05

.05

.04

.06

.51

.05

.04

.03

.03

.03

.03

.03

.02

.05

.06

.81

.54

.31

.32

.14

.25

.16

.11

1.70

1930-31

1

2____

3

4

5

6

7

8

9

10

11

1?,

13

14

15

16

17

18

19

20

?,1

?,?,

23

24

25

?,fi

27

28

27

30

31

1.38

1.60

1.45

.42

.18

.11

.10

.14

.12

.08

.08

.09

.08

.07

.08

.06

.04

.05

.03

.06

.04

.04

.03

.03

.02

.02

.01

.02

.01

.02

.01

0.12

.10

.09

.10

.12

.08

.03

.04

.05

.04

0.03

.02

.03

.02

.03

.03

.03

.01

.01

.02

.03

.03

.02

.02

.05

.04

.06

.06

.06

.08

.06

.05

.05

.06

.05

.06

.06

.04

.02

.04

.03

0.03

.03

.03

.02

.04

.04

.01

.02

.02

.06

.10

.08

.11

.20

.26

.30

.16

.12

.10

.20

.26

.24

.12

.10

.83

.54

.61

.36

.20

.20

0.24

.18

.21

.22

.44

.38

.26

.23

.20

.26

.18

.12

.13

.08

.10

.40

.50

.96

.90

.50

.29

.20

.17

.15

.26

.20

.35

.32

.25

.21

.16

0.15

.22

.23

.30

,29

.19

.23

.27

.28

.18

.14

' .12

.14

.10

.10

.09

.10

.11

.09

.09

.10

.10

.08

.08

.07

.06

.07

.08

.08

.58

0.31

.10

.10

.10

.10

.09

.06

.06

.04

.04

.04

.03

.02

.02

.02

.02

.01

.01

.01

.02

.04

.04

.04

.03

.02

.01

.01

.01

1.30

1.89

1.66

3.57

.86

1.56

.39

.15

.38

.34

.31

.11

.06

.07

.05

.04

.04

.06

.02

.24

.02

.06

.04

.04

.04

.01

.01

.01

.02

.01

.01

.02

.01

.01

0.70

.18

.15

.09

.05

.05

.03

.03

.03

.03

.03

.02

.02

.03

.74

.07

.29

.23

1.69

.63

.77

.44

.26

5.03

3.96

1.83

.86

.64

.49

.26
QUANTITIES OF SUSPENDED SEDIMENT 17

TABLE 5. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Cisco, Utah, May 14, 1929, to Sept. SO, 1939 Continued

1931-32

Day

1 

2 

3 

4 

5 -

6 

7....

8 

9 in

11 

12...

13 

14 

15 

16

17

18...

19

20 

21 

99

23 

94

25...

?«

27 

?,8

29...

30

31 

October

0.18

3.03

.71

.32

.15

.16

.09

.10

.13

.08

.06

November

0.04

03

.56

.63

.07

.04

04

December

0.05

fM

.08

January

.08

.06

February

0.14

.42

March

0.43

9Q

.28

.11

fU

.06

.48

.16

.16

April

0.19

.98

.50

.44

.84

.57

.54

.39

.48

May

0.54

.49

.38

.72

.30

.26

.26

.24

.14

June

0.13

.10

.12

.11

.14

.09

.11

.10

July

0.08

.09

.10

.29

.13

.16

.06

.04

.03

August

0.31

.11

.03

.03

.15

1.06

.15

.99

September

0.19

.06

.04

.04

.03

.03

.03

.16

.10

1932-33

1

?,

3

4

6

6

7

8

9

10

11

1?,

13

14

16

16

17

IS

19

?,0

?,1

?,?,

?,8

?,4

«fi

9,6 X7

 »

W

30

31

0.04

.02

.02

.06

.06

.02

.13

.04

O fU

.03

.02

.04

fM

.04

.02

0.14

.34

0.06

.08

.08

03

.08

0.15

.28

.14

.08

.32

.42

99

.34

0.27

.17

.11

no

.10

.08

.06

0.07

.21

.08

.04

.04

.03

.04

1.48

.21

.34

.25

.02

.02

.01

0.02

.02

.01

.07

.0

.46

.18

.04
18 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 5. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Cisco, Utah, May 14, 1929, to Sept. 30, 1939 Continued

1933-34

Day

l .

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...

October

0.02

.64

.09

.04

.02

.02

.02

.03

November

0.04

.03

.03

.02

.03

.01

.03

.01

.02

December

0.04

.04

.06

.03

.05

January

0.05

.03

.03

no

.03

.01

.01

February

0.03

.02

no

no

04

.04

March

0.01

.01

.01

.02

.02

April

0.03

.16

May

0.09

.25

.16

.33

.12

.08

.06

.06

.06

June

0.09

.04

.04

.02

.02

.02

.01

.16

.02

July

0.01

.01

.01

.02

.37

.12

August

0.03

.02

.02

.17

.20

.22

.03

1.52

September

0.03

.02

.26

.05

.03

.03

.02

.04

.11

.41

.07

.09

1934-35

1 

2

3

4...

5 

6

7

S

9

10

11

1?

13

14...

15.. _

16

17

18

19

an

21

22

33

24 ._ 35

36

27

28

39

30

31

0.07

.02

.03

.03

.02

09

.02

.03

no

.03

04

.06

.13

09

.03

.04

no

0.02

.05

.05

.05

12

.08

.04

04.

.03

no

no

0.04

.07

.03

no

04

Ofi

.07

.04

.05

.08

.06

0.07

04

no

03

no

no

no

.08

0.05

.04

.04

no

.07

.07

.06

.05

0.35

1.00

98

1.26

1.08

.56

.40

.61

.82

.56

1.02

97

.73

.39

.37

.46

.36

.25

0.23

.15

.23

.14

.32

.37

.46

.53

.54

.24

.42

.20

.42

.53

.52

.23

0.20

.26

.32

.37

.35

.32

.32

.27

.22

.19

.17

.13

.12

.12

.12

.09

.07

0.08

.12

.10

.05

.05

.07

.20

.18

1.86

1.20

.31

.24

.03

0.48

.25

.07

.08

.05

.33

.08

1.67

1.05

.04

.34

.63

.54

1.26

.91

.97

0.11

.50

.62

.18

.04

.02

.02

.01

.07

.27

.34

.52

.58
GEOLOGICAL SUEVEY WATER-SUPPLY PAPER 998 PLATE 2

LINE OF DEMARCATION OF INFLOW AND WATER OF LAKE MEAD APPROXIMATELY 90 MILES ABOVE

BOULDER DAM.
GEOLOGICAL SURVEY WATER-SUPPLY PAPER 998 PLATE 3

DEPOSIT IN SLACK-WATER AREA ABOUT 97 MILES ABOVE 

BOULDER DAM.
QUANTITIES OF SUSPENDED SEDIMENT 19

TABLE 5. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Cisco, Utah, May 14, 1929, to Sept. 30, 1939 Continued

1935-36

Day

1

2

3

4

5

6

7

8

g

in

11i?is

14

IS

Ifi

17

18

19

9,0

21 

W,

23

24

25

26

37

?*

39

30

31

October

0.23

.04

.03

.02

.01

.01

.01

.02

.02

.02

November

0.02

.03

.02

.02

.01

.02

.01

December

0.03

.03

03

.01

.02

.03

.03

.03

.06

January

.00

.01

.03

.05

.01

.02

February

0.04

.06

.07

.06

.08

.07

.05

.04

March

.03

.03

.04

.03

.03

.05

.06

.09

.06

.05

.04

April

0.04

.04

.03

.04

.67

2.05

1.05

.75

.70

60

.41

.44

.39

.27

.20

.19

May

0.13

.11

.28

.34

.18

.13

.12

.08

.14

.14

.16

.10

.08

.09

.07

.07

.05

.07

June

0.06

.06

.06

.08

.05

.06

.04

.04

.04

.05

.05

.04

.04

.10

July

0.13

.04

.02

.03

.41

3.75

.40

.35

.11

.06

.46

.42

.26

.05

.13

.14

.66

August

0.64

.31

.30

1.52

.81

.48

.52

.28

.10

.07

.09

.44

1.00

.38

.16

.05

.17

1.49

September

1.71

1.40

.84

.24

.13

.06

.36

.26

.17

.06

.04

.03

.02

.02

.02

.02

.02

1936-37

1

?,

3

4 .

5

6

7

8

9

10

11 

1?

13

14

15

16

17

18

19

20

2122

23

94

25

26

W

28

TO

30

31

0.03

.06

.02

.02

.02

.81

.31

.40

.06

.10

.48

0.22

.05

.04

.02

.04

.04

.04

.01

0.02

.02

.06

.05

.10

.14

.03

.02

.02

0.04

.05

0.04

.03

.09

.18

.38

0.22

.18

.28

.35

.30

.20

.18

.20

.23

.26

.20

.34

.22

.12

.08

.06

0.04

.04

.08

.12

.12

.68

1.30

1.45

1.18

.82

.68

.45

.47

.60

.36

.37

.25

0.26

.31

.49

.52

.42

.47

.41

.36

.24

.33

.25

.14

.10

.09

.12

.16

0.10

.13

.09

.09

.07

.08

.10

.09

.10

.07

.10

.03

.06

.02

.03

.14

0.12

.07

.11

.70

.91

1.50

4.67

.84

.19

.20

.05

.14

.45

QQ

0.10

.06

.64

.15

.05

.05

.04

.05

.36

.09

.08

.04

.02

1.43

1.82

2.80

2.37

4.74

.26

.20

.16

.17

.10

.06

.04

.04

.02

.02

.04

.06

.14

.58

.08

.04
20 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 5. Mean daily concentration of suspended sediment in Colorado River 

at gaging station near Cisco, Utah, May 14, 1929, to Sept. SO, 1939 Continued

1937-38

Day

1... .

2

3

4

fi

6

7

8

9

10

11

1?

13

14

15

16

17

18

19

20

?122

93

24

25

26

27

28

29

30

31

October

0.07

.14

.06

.06

O4.

.03

.02

.02

1.27

1.36

.82

.55

.20

.05

fU

.04

03

November

0.03

.03

.18

.38

.26

.05

.02

.02

.02

.02

.02

.03

.02

.02

December

0.02

.02

.02

.02

.02

.04

.02

98

.35

.56

.12

.08

.06

04

.02

.04

.02

January

0.03

.03

.04

.02

.02

.03

.02

.02

.06

fU

.04

.02

.02

February

0.03

fM

.04

fU

.03

.26

.62

.36

.26

.08

04

04

March

0.48

3.28

3.23

.21

.20

.07

4A

.45

.39

.26

.19

.68

.40

.17

.16

April

0.05

fU

.51

.36

.30

.71

1 4.^1

.96

1.19

1.22

1.29

.87

.88

.87

.61

May

0.53

.54

.42

.35

.16

.17

.24

.47

.41

.27

.22

.20

.16

.16

.30

.27

June

0.15

.17

i - 11

.17

.09

.15

.09

.16

.10

.14

.10

.22

.11

.17

.14

July

0.16

.13

.08

.12

.10

.42

.35

.16

.14

.08

.05

.06

.09

.06

August

0.06

.04

.05

.03

rtO

.47

.42

.25

.10

1.32

.13

.08

fU

.04

.04

.03

.06

September

0.80

1.28

2.16

1.48

01

2.44

1.94

.67

.25

.27

.15

.07

.06

.06

.04

.03

1938-39

1 

2

3

4

fi

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

01

0.08

.05

.07

2.85

.43

.16

08

.08

.07

.05

03

.02

fM

rtO

0.03

.03

.03

03

.04

.04

.02

.02

.03

.02

.02

.02

03

f\A

0 04

.06

.05

.05

.02

rtO

, .01

.01

.02

.01

rtO

.02

.02

.01

O ftA

.03

.02

fM

.02

no

0.02

.03

.04

.02

n3

f\A

fU

fU

.05

0.04

nd

n^

.14

.39

.38

.36

.57

.94

79

.82

AK

-.26

0.23

.64

fift

.53

.33

.20

.28

.16

.10

.11

.13

.11

.46

.20

Q9

.52

.48

.40

.38

.20

.23

.16

.22

.15

.14

.09

.12

.17

.23

.13

.25

.24

.16

.16

.09

.11

.08

.12

0.15

.22

.12

.10

.14

.07

.12

.17

.10

.07

.06

.04

.07

.08

.08

.04

.03

,04

03

0.03

.03

.03

.01

.01

.01

.01

.02

.01

.01

.03

.03

fM

.02

.02

.02

.02

0.03

.03

.02

.84

.10

.04

.03

.04

.02

.02

1.24

2.14

.66

0.09

4.55

.73

1.79

1.51

.54

1.08

1.62

.34

.15

.07

.05

.03

.02

.02

.03

.12
QUANTITIES OF SUSPENDED SEDIMENT 21

TABLE 6. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Cisco, Utah, 

Oct. 1, 19S9, to Sept. 30, 1941

1939

October

Day

1 .

2 . 

3 .

4. 

5 

6 

7... 

8 .

J 

10. 

11 

12 

13.... 

14 

15 

16 

17 

18 

19 

20 

21..- 

22....

23 

24....

26.... 

26 

27 

28 

29 

30 

31-...

Mean 

discharge 

(secondfeet)

2,590

2,590

2,680

2,420

2,500 

2,590

2,500

2,590

2,500

2,270

2,190

2,120

2,040

2,190 

2,370 

2,350

2,270

Suspended sediment

Mean 

percent

0.04

.04

.03

.02

.14 

.03

.03

.02

.01

.01

.01

.01

.01

.26 

.07 

.04

.04

Tons per 

day

2,800

2,800

2,170

1,300

9,450 

3,000

2,000

1,400

675

613

591

572

551

15,400 

4,480 

2,540

2,450

November

Mean 

discharge 

(secondfeet)

2,270

2,500

2,590 

2,680

2,680 

2,760

2,680

2, 590

2,590

2,590

2,320

2,390

2,320

2,500

2,500

2,590

-

Suspended sediment

Mean 

percent

0.02

.02

.02 

.02

.02 

.06

.05

.01

.01

.01

.04

.02

.02

.02

.01

.02

Tons per 

day

1,230

1,350

1,400 

1,450

1,450 

4,470

3,620

699

699

699

2,500

1,290

1,250

1,350

675

1,400

December

Mean 

discharge 

(secondfeet)

2,420

2,230

2,220 

2,270

2,270

2,200

2,320

2,120

1,920

1,800

2,140

1,670

1,860

1,980

1,710

1,460

Suspended sediment

Mean 

percent

0.02

.01

.02 

.01

.01

.01.

.01

.01

.01

.01

.02

.01

.01

.02

.01

.02

Tons per 

day

1,310

602

1,200 

613

613

594

626

572

518

486

1,160

451

502

1,070

462

788

1940

January

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 

1,840 

2,060

2,420

2,420

2,250

2,110 

2,190

2,590

2,120

1,710

1,840

1,780

1,960

1,900

2,200

2,500

2,390

0.01 

.01

.02

.01

.01

.01 

.01

.04

.02

.01

.02

.01

.02

.03

.04

.04

.03

497 

556

1,310

653

608

570 

591

2,800

1,140

462

994

481

1,060

1,540

2,380

2,700

1,940

February

2,420 

2,590

2,760 

2,760

2,370

2,280

2,110 

2,140 

2,150

2,140 

2,150

2,140

1,920

2,060

2,070

2,760 

3,400 

3,300

0.02 

.05

.10 

.08

.05

.04

.02 

.01 

.01

.02 

.01

.02

.01

.01

.01

.08 

.50 

.20

1,310 

3,500

7,450 

5,960

3,200

2,460

1, 140 

578 

580

1,160 

580

1,160

518

556

559

5,960 

45,900 

17, 800

March

2,850

2,680 

2,590 

2,500

2,370 

2,350

2,300

2,420

2,400

2,190

2,200

2,390

2,370

2,680

3,300

4,370

4,580

0.24

.11

.12 

.08

.03 

.03

.02

.02

.02

.02

.01

.02

.01

.03

.04

.17

.26

18,500

7,960 

8,390 

5,400

1,920 

1,900

1,240

1,310

1,300

1,180

594

1,290

640

2,170

3,560

20,100

32,200
22 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 6. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment for the Colorado River at gaging station near Cisco, Utah, 

Oct. 1, 1939, to Sept. 30, 1941 Continued

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

Mean 

discharge 

(secondfeet)

3,680

3,970

3,400

3,400

3,680

3,490

3,210

3,580

5,320

5,320

7,430

10,900

11,600

11,900

12,200 

10,600

Suspended sediment

Mean 

percent

0.23

.22

.18

.15

.18

.16

.16

.42

.43

.31

.78

.67

.50

.39

.38 -.26

Tons per 

day

22,800

23,600

16, 500

is, §60

17,900

15,100

13,900

40,600

61,800

44,500

156,000

197,000

157,000

125,000

1'25. 000 

74,400

May

Mean 

discharge 

(secondfeet)

10, 300

9,360

11,900

15,100 

16,200

17, 300

22,100 

23,300 

25,000

22,500 

21,300

21,300

16,600

15,100

14,300

15,400

17,700

18,500

Suspended sediment

Mean 

percent

0.22

.16

.29

.38 

.34

.25

.37 

.36 

.25

.18 

.14

.15

.10

.08

.07

.10

.10

.09

Tons per 

day

61,200

40,400

93,200

155,000 

149,000

117,000

221,000 

226,000 

169, 000

109,000 

80,500

86,300

44,800

32,600

27,000

41,600

47,800

45,666

June

Mean 

discharge 

(secondfeet)

21,700 

22,500

20,500

17,300

14,000

10,800 

9,960

11,600

11,900

11,200 

10,600

9,360

8,780

7,180

5,880

5,000

Suspended sediment

Mean 

percent

0.15 

.14

.11

.07

.07

.06 

.06

.09

.08

.05 

.04

.04

.64

.63

.67

.04

Tons per 

day

87,900 

85,000

60,900

32,700

26,500

17,500 

16,100

28,200

25,780

15,100 

11,400

10,100

9,480

5,830

11,100

5,480

1940

1 

2__ 

3 

4 

5. 

6 

7 

8 

9_ 

10 

11 

12 

13 

14 

15 

16 

17 

18..-

1Q

20--

21 

22 

23 

24 

25--.

26 

27 

28 

29_ 

30 

31___-

4,580

4,370

4,170

3,490

3,630

2,590

2,190

2,090

2,940

2 ' 680

2,850

2,680

2,200

O AQft

1,600

July

6.11

.04

.03

.01

.01

.01

.02

.01

3.90

KA

.05

.02

no

.02

03

13,600

4,720

3,380

942

980

699

1,180

564

310,000

39 ' 100

8,460

3,620

1,190

1,100

000

i ^nn

1,460

1,200

1,200

1,220

1,080

913

895 

841

796

712

704

712

1,080,

1,200

3 ion

3,210

2,850

2 850

August

0.04

.03

.62

.67

.35

.02

.01 

.02

.02

.03

no

.15

.05

03

i df\

1.32

.35

.18

1,580

972

648

2,310

10,200

493

242 

454

430

577

380

2,880

1,460

972

114,000

26,900

13,800

S

2,420

2,040 

2,040

1,650

1,480 

1,380

1,410

1,440 

1,430

1,810

2,120

2,500

3,580

4,270

3,970

3,870

3,780

9,430

September

6.07

.09 

.14

.05

.02

.02

.02

.03 

.10

.06

.10

1.16

.74

.76

.66

.31

.16

2.91

4,570

4,966 

7,710

2,230

799

745

761

1,170 

3,860

2,930

5,720

78,300

71,500

87,600

70,700

32,400

16,300

741,000
QUANTITIES OF SUSPENDED SEDIMENT 23

TABLE 6. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment for the Colorado River at gaging station near Cisco, Utah, 

Oct. 1,1939, to Sept. 30,1941 Continued

1940

Day

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 

Oetober

Mean 

discharge 

(secondfeet)

10,900

8,220

7,430

6,450

5,100 

5,100

4,580

4,170

3,580 

3,490

3,300

3,300 

3,210

3,030

2,940

4,170

3,120

Suspended sediment

Mean 

percent

2.29

1.33

1.00

.98

.37 

.26

.31

.14

.04 

.07

.05

.05 

.03

.02

.04

1.10

.21

Tons per 

day

674,000

295,000

201, 666

171,000

50,900 

35,800

38,300

15, 800

3,860 

6,590

4,460

4,460 

2,600

1,650

3,190

124, 000

17, 700

November

Mean 

discharge 

(secondfeet)

3,120 

3,030

3,580

3,210

2,940

3,030

3,210

2,760

2,270

3,030

3,300

3,210

3,120

3,030

2,850

2,850

Suspended sediment

Mean 

percent

0.08 

.05

.23

.11

.02

.03

.02

.02

.01

.02

.04

.04

.02

.02

.02

.01

Tons per 

day

6,750 

4,100

22,200

9,530

1,590

2,450

1,730

1,490

613

1,640

3,560

3,460

1,680

1,640

1,540

770

December

Mean 

discharge 

(secondfeet)

2,850 

2,850

2,760

2,680

2,680

2,590

2,940

2,340

1,640

2.420

2,250

2,680

2,500

2,590

Suspended sediment

Mean 

percent

0.01 

.01

.02

.01

.01

.01

.01

.02

.02

.06

.04

.06

.03

.04

Tons per 

day

770 

770

1,490

724

724

699

794

1,260

886

3,920

2,430

4,350

2,030

2; 810

1941

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-.-.

2,760

2,420

2,190

1,840

2,010

2,060

2,270

2,400

2,420

2,250

2,010 

2,270

2,420

2,420

me.

2,250

2,370

January

0.03

.02

.02

.02

.02

.02

.02

.02

.02

.02

.01 

.02

.02

.02

.01

.02

2,240

1,310

1,180

994

1,080

1,110

1,230

1,300

1,310

1,220

543 

1,230

1,310

1,310

608

1,280

I

2,590 

2,590

2,220

2,110

2,280

2,400

2,850

3,490

2,500

2,940

2,940

3,120

3,030

3,400

2,680

"'ebruary

0.03 

.03

03

.02

.02

.03

.16

.20

.10

.14

.10

.20

.17

.20

.18

2,100 

2,100

1,800

1, 140 '

1,230

1,940

12, 310

18,850

6,750

11,110

7,940

16,800

13,900

18, 400

13, 000

2,500

2,940

2,940

2,760

2,590

2,500

2,370

2,680

2,850

2,760

3,030

3,780

4,070

5,540

4,680

4,270

5,216

March

0.12

.17

.12

.14

.08

.05

.37

.06

.08

.11

.11

.30

.32

.52

.30

.26

.4fi

8,100

13,500

9,530

10,400

5,590

3,380

23, 700

4,340

6,160

8,200

9,000

30,600

35,200

77,800

37,900

30, 000

64, 700
24 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 6. Mean daily 'discharge, mean daily concentration, and daily load of 

suspended sediment for the Colorado River at gaging station near Cisco, Utah, 

Oct. 1, 19S9, to Sept. SO, 1941 Continued

1941

April

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....

Mean 

discharge 

(secondfeet)

7,180 

6,690

6,000

5,650

5,540

6,810 

6,450 

6,340

6,280 

6,340

5,990

5,600

5,200 

5,000

5,990

7,950 

11,200 

15, 800 

19,700 

19,700

Suspended sediment

Mean 

percent

0.78 

.57

.30

.30

-.31

.62 

.44 

.34

.28 

.31

.24

.25

.16 

.22

.31

.50 

.67 

.94 

1.02 

.83

Tons per 

day

151,000 

103,000

48,600

45,800

46,400

114,000 

76,600 

58,200

47,500 

53,100

38,800

37, 800

22, 500 

29,700

50,100

107, 000 

203, 000 

401, 000 

543, 000 

441, 000

""

May

Mean - 

discharge 

(secondfeet)

22,900

27, 900 

40,500

40,500 

37,000 

34,400 

34,800 

38, 300

47,700

63,400

57,400 

48,200

46,400 

45,000

28,800

31,300

35, 700 

36,100

34, 400

27, 900

Suspended sediment

Mean 

percent

0.78

.76 

1.12

.80 

.66 

.49 

.50 

.57

.60

.38

.31 

.32

.24 

.19

.22

.18

.20

.17

.12

.11

Tons per 

day

482,000

573, 000 

1,220,000

875, 000 

659, 000 455, ooa

470, 000 

589,000

773,000

650, 000

480, 000 

416, 000

301,000 

231,000

171, 000

152,000

193, 000 

166, 000

112, 000

82,900

June

Mean 

discharge 

(secondfeet)

26,200

26,200

27,100

27,100 

24,100 

21,300

20,100

22,900

28,400

31, 300 

31,300

30, 500 

30,900

27,900

21,700

Suspended sediment

Mean 

percent

0.09

.09

.10

.13 

.12 

.12

.09

.11

.14

.15 

.17

.10

.43

.11

.08

Tons per 

day

63,700

63,700

73,200

95,108 

78,100 

69,000

48,800

68,000-

107,000

127,000 

144,000

82,400 

359,000

82,900

46,900

1941

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___.

29_...

on

31 

J

16, 900

14, 300

13, 300

11,900

11,200

10, 900

10, 300

9 fififi

8,500

7,430

7 fiQfi

7,950

6,690 

6,450

5,650

5,100

4,580

Fuly

0.07

.06

.07

.05

.06

.07

.05

.14

.04

.17

.07

.05

.04 

.21

.08

.04

.03

31, 900

23,200

25, 100

16,100

18,100

20,600

13,900

36,500

9,180

34, 100 

14,500

10,700

7,220 

36,600

12,200

5,510

3,710

3,800

3,800

2,760

2,500

4,370 

8,690

6,690

5,320

5,000

4,580

5,880

5,650 

4,890

4,270

3,300

2,760

2,220

2,100

August

0.02

.02

.02

.05

.78 

3.91

.85

.29 -.14

.10

1.13

1.30 

.20

.14

.08

.03

.03

.03

2,050

2,050

1,490

3,380

92, 000 

917, 000

154,000

41, 700

18, 900

12,400

179, 000

198, 666 

26,400

16,100

7,130

2,240

1,800

1,700

2,000

1,990

1,920

1,740

1,630

2,220

3,300

4,170

3,870

3,870

3,970

7,850

12,600

8,220 

7,000

5,400

5,210

September

0.05

.04

.03

.03

.03

.03

.77

.16

.07

.05

.05

1.57

2.03

1.94 

.66

.17

.10

2,700

2,150

1,560

1,410

1,320

1,800

68,600

18,000

7,310

5,220

5,360

333,000

691, 000

431, 000 

125,000

24,800

14,100
QUANTITIES OF SUSPENDED SEDIMENT 25

TABLE 7. Mean daily concentration- of suspended sediment in the Colorado River 

at gaging station at Lees Ferry, Airz., Oct. 1, 1928, to Dec. 16, 1933

1928-29

Day

1

?,

3 

4 .

5 

6 

7....

8....

9....

10 

11 

12...

13...

14 

15 

16 

17

18 

19

20 

91

oo

oo

94

W)

?,6

27

?,8

9Q

QA

O1

October

0.17

.33

Kf\

1.12

Q7

.62

44

November

1.56

.92

.77

.38

.35

.38

.35

.33

.28

.31

December

0.24

.21

.20

.16

.14

.16

.09

.17

January

0.23

.12

.12

.16

.29

.30

1Q

February

0.35

0.22

.15

.38

.30

.33

March

0.37

.24

.58

1.16

1.69

1.93

2

04.

4

Q9

2.13

.81

.87

April

0.79

1.01

1.00

1 93

1.43

1.13

1.08

.74

.85

1.03

1.38

1.12

l."06

1.16

1. 10

1.14

.95

.64

May

0.50

.66

.72

.58

.70

.70

.94

1.06

1.22

1.25

1.14

.90

1.19

1.02

.87

1.03

1.06

.99

.89

.77

.86

.84

84.

June

0.86

.69

.68

.58

.81

.67

.51

.63

.55

.76

.50

.32

.40

.40

.37 .'37

July

0.41

.33

.31

.30

1.41

.65

.31

.33

.28

.36

.34

2.18

2.88

4.20

3.79

August

3.80

5.24

3.68

5.67

5.35

4.59

4.12

9 OS?

5.65

3

AQ

1.77

.81

K7

.53

.51

<?Q

4fi

.87

1.31

September

1.68

2

1 Q

3.57

3.36

2.60

1.38

1.30

70

.66

2.26

6.07

3.31

1.66

1929-30

4-..

6 .

8

Q

10 

11

12

i Q

14...

15_._

16 

17...

18...

19

20...

91

22

23 

?4

OK

26

97

28-.

29...

QA

31

1.67

.74

.56

.52

54

.61

.58

' .68

.74

.79

.61

49

.43

0.47

.41

.50

49

.49

.52

.38

.38

.37

.45

.28

0.31

49

on

.33

.37

.31

.33

.31

.26

.15

99

.20

0.17

.26

.39

.45

.33

.31

.27

.28

.27

.22

26

.18

.23

0.45

.36

.31

.38

.33

.58

.58

.45

1.01

.69

0.57

.41

.41

.47

.31

.35

.33

.38

.39

.45

.49

.49

0.43

.32

.31

.54

.78

1.21

1.24

2.06

1.48

1.13

1.70

1.14

1.38

1.23

1.16

.91

.87

.90

1.05

1.22

1.24

.91

.92

0.88

.80

.87

.82

.61

.53

.51

.52

.37

.33

.50

.51

.38

.45

.59

.54

.44

.68

.74

0.90

1.33

1.38

.97

.92

.82

.70

.66

.63

.90

.89

.78

.45

.66

.58

.54

.44

.44

.46

.69

.58

.52

1.01

1.04

.60

.58

.46

.53

.42

.39

0.31

.31

.26

.22

.17

.17

.26

2.20

1.72

1.09

1.82

2.82

2.44

1.98

1.06

1.16

3.63

1.54

->

2.98

3.18

3.40

8.33

8.02

7.13

4.15

3.33

2.88

2.31

1.73

1.59

1.10

.86

.57

0.39

2.29

1.36

1.37

.94

.68

.38

.34

.27

.29

.69
26 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 7. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station at Lees Ferry, Ariz., Oct. 1, 1928, to Dec. 16, 1935 Continued

1930-31

Day

I... .

2____

3 

4

6 

6 _

7 _

8 .

9_._.

10 

11_._

12 

13 

14...

15 

16 

ITIS 

19 

20 

21 

22 

23...

24 

25...

26...

27 

28 

29 

30 -

31 

October

0.80

.60

.60

1.10

1.05

1.05

1.15

.90

.75

.85

.60

.60

.68

.55

.48

.50

.58

.52

.52

.49

.40

.49

.45

.43

.40

.35

.33

.30

.40

.38

.36

November

0.35

.35

.35

.35

.35

.37

.35

.35

.32

.31

.30

.30

.35

.41

.37

.35

.33

.80

.70

.68

.55

.53

.50

.48

.45

.41

.32

.26

.25

.24

December

0.23

.32

.24

.24

.24

.28

.27

.25

.23

.22

.24

.25

.24

.24

.23

.25

.27

.25

.24

.20

.18

.16

.15

.15

.15

.15

.24

.30

.35

.40

.44

January

0.27

.26

.60

.40

.75

.40

.25

.25

.23

.22

.22

.23

.24

.25

.25

.26

.27

.32

.37

.30

.27

.30

.30

.33

.30

30

.35

.38

.40

.40

.40

February

0.40

.41

.45

.45

.50

.45

.35

.38

.41

.38

.37

.37

.37

.39

.41

44

.48

.75

.58

.56

.52

.48

.45

.38

.37

.37

.36

.32

March

0.29

.27

.29

.28

.27

.26

.26

.27

.28

.30

.35

.32

.30

.30

.30

.31

.36

.43

.35

.29

.32

.35

.39

.42

.46

.47

49

.51

.53

.55

.52

April

0.47

.44

.41

.35

.30

.27

.28

.29

.29

.30

.30

.32

.34

.36

.38

.32

.40

.38

.55

.55

.56

.56

.56

.65

.57

.56

.56

.58

.61

.61

May

0.67

.65

.65

.65

.63

'.55 .59

.60

.63

.65

.67

.75

.60

.58

.52

.47

.47

.49

.60

.91

1.50

1.24

.98

.97

.85

.66

.65

.65

73

.59

.59

June

0 59

.50

.65

.69

.49

.57

.40

.54

.51

.58

.60

.56

.54

.52

.50

.48

.47

.47

.47

.44

.43

.42

.37

.32

.32

.32

.30

.27

.24

.22

July

0.25

.23

.31

.40

.50

.62

.70

.60

.40

.35

.30

.25

.23

.20

.18

.17

.17

.17

.20

.28

.20

.18

.15

.13

.15

.20

.14

.13

.13

1.25

1.72

August

1.69

1.04

1.32

2.92

3.11

2.22

1.77

1.27

.94

1.59

1.24

1.45

1.03

.77

.83

.83

.79

.60

.82

.47

.44

.65

.59

.75

.77

.«

.ftl

.35

.20

.16

.28

September

0.27

.25.

.23

.22

.22

.22

.22

.23

.25

.25

.30

.25

.22

.18

.15

.51

.51

2.87

1.82

2.61

2.46

2.12

1.97

2.92

5.51

3.22

2.29

2.53

2.2?

2.42

1931-32

1 

3

4 

5

6

7

8

9

10

11

1?

1 o

14

16

17

18

19

20

W,

00

?4

25

?6

97

38

29

30

SI

2.01

2.90

1.76

1.08

1.25

.84

.49

1.82

2 9ft

1.29

.78

.60

0.38

.35

.41

.55

.71

1.36

.81

.82

.48

.45

.38

.29

.45

.44

.56

.43

.54

0.45

.35

.50

44

.43

.35

.34

.17

.26

0.26

.45

.88

.86

1.05

.91

.99

1.17

0.75

.81

.78

1 79

1 29

1.26

1.21

1.07

1.39

1.65

2.00

2.08

1.82

1.62

1.18

1.31

1.71

1.32

1.53

1.24

1.17

1.11

.95

1.05

.93

0.86

.99

1.07

1.03

1.04

.99

1.09

.87

1.13

1.19

1.13

1.12

1.37

1.36

1.11

1.06

.97

.98

.96

.96

.88

.83

.83

.81

.84

.78

0.82

.74

.61

.62

.57

.59

.50

.52

.48

.56

!

.40

.60

.51

.49

.63

.57

.43

.47

.45

.48

.48

.49

.69

.70

0.83

.68

.52

.75

.66

.66

.61

.53

.30

1.56

1.40

1.36

.87

.60

.60

.64

.49

.34

.28

.27

.26

.26

.80

.63

1.52

.99

.71

.49

.38

.45

.29

.19

.15

.54

.58

1.07

3.97

4.11

2.44

1.74

2.38

5.81

6.27

5.57

4.40

3.62

1.87

1.27

1.02

.74

.39

.49

.35

1.57

1.42

1.42
QUANTITIES OF SUSPENDED SEDIMENT 27

TABLE 7. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station at Lees Ferry, Ariz., Oct. 1, 1928, to Dec. 16, 1988 Continued

1932-33

Day

1.. .

2 

3 _

4 

5 

6

7 

8. 

10

11... to

13

14 

15...

16 

17 

18

19 

20 

21 

22 

58

24 

OR

26

27 

OQ

29

30

31...

October

0.71

.52

.37

34

.30

.29

.41

.52

.40

Novem- 

«ber

0.42

.35

.37

^n

.34

34

.34

.34

.26

'

December

0.31

.28

.35

.26

.19

.18

.21

.19

.27

January

0.21

.22

.23

.08

.19

.36

.26

.19

February

0.25

.23

.21

.23

.19

.21

.33

March

0.41

.41

.52

.55

.54

.54

.44

.42

.35

.34

April

0.52

.51

.43

.36

.40

.40

.37

.34

.37

.34

.30

.33

.33

.36

.34 .'48

.46

.40

May

0.60

.77

.93

1.19

1.14

1.13

.93

.87

.84

.85

.73

.63

.53

.55

- .47

.42

.69

.93

1.38

1.55

1.64

1.24

1.05

1.01

1.07

1.03

.72

June

0.92

1.09

1.11

1.09

1.02

.88

.73

.74

.73

.76

.75

.58

.61

.68

.49

.54

.47

.45

.56

.47

.51

.59

.51

- 71

.57

.46

.52

.45

July

0.38

.36

.29'

.30

.56

1.35

2.27

1.69

3.33

2.46

1.62 . 97

.97

.68

.90

.39

.48

1.06

.78

August

0.61

1.16

.96

.93

1.02

2.54

2.12

2.37

1.45

.93

.98

.95

1.05

.49

.39

September

0

«y>

oo

.16

1Q

9 9Q

2.18

 7 Ot

6

O«l

A. 1Q

9 on

9 99

9 Ql

2.2&

OR

.72

1933

1

?:

3

4

5 

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

?4

?f>

26

27 

28

29

30

31

0.58

3.46

3.24

4.04

3.71

2.03

1.23

.99

1.58

.99

.45

.46

.45

.34

.38

0.39

.35

.45

.40

.52

.45

.49

.40

.38

.43

.41

.39

.41

.44.

.49

1.26

.49

.50

.32

.40

.59

.44

725606 47-
28 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 8. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Grand Canyon, Ariz., Oct. 1, 1926, to Sept. 30, 1929

1925-26

Day

1 

2....

3. 

4....

5 .

6 

7....

8

9-._

10 

11 

n

13

14

15

16 17

18 

19

20

21

22...

513

74

2fi,

26

27

28

29...

30

31

October

2.86

r

.50

.37

November

0.38

.43

.37

.34

.27

.28

.25

.16

.15

December

0.16

.23

.14

.16

.11

.10

.07

.09"

.13

January

0.09

.12

.08

.07

.06

.05

.05

.06

February

0.07

.10

.11

.11

.16

-.22

.18

.14

March

0.14

.18

.32

.44

.54

.68

1.27

1.13

1.09

April

0.86

3.15

2.17

1.87

1.94

3.55

2.55

May

1.65

1.72

,

3.02

1.35

.71

.67

1.23

2.11

2.38

June

1.28

1.04

1.16

.64

.80

.39

.37

.24

July

0.21

.15

.44

.48

1.09

1.25

.72

.34

.20

August

0.50

.24

.77

.89

.62

60

.55

Septem 

her

0.11

.07

1 85t

1.03

.27

1.25

1.08

1926-27

1....

2...

3 

4 .

5 

6

7....

8

9_ 

10 

11 

13 

14...

15...

16...

17

18

19

20

21...

22...

23

24...

26

26

27 

98

OQ

30

31 

1.36

.87

1.17

.62

.60

.23

.20

1O

0.10

.11

.08

.15

.09

.12

.12

0.15

.59

.60

.57

.15

.06

.05

" 0.04

.07

.17

.19

.i2

.11

.14

.11

.10

0.08

.08

.10

.36

2.85

.94

.84

.70

0.77

.91

.84

.65

.64

.50

.37

.45

.77

1.18

1.90

2.07

1.52

.73

.50

.54

fin

1.04

1 00

1.67

1.38

2.32

2.34

2.30

1.07

.98

1.90

2.19

2.77

1.08

0.49

.59

.72

.91

.99

.83

.73

.92

4.69

.83

.85

1.01

1.50

.31

.16

.20

1.22

0.96

.85

3.16

2.09

1.15

.75

.4i

.23

2.06

2.16

.98

3.86'

13.81

5.38

2.99

1.89

.95

2.77
QUANTITIES OF SUSPENDED SEDIMENT 29

TABLE 8. Mean daily concentration of suspended sediment in the Colorado River at 

gaging station near Grand Canyon, Ariz., Oct. 1, 1925, to Sept. SO, 1929 Continued

1927-28

Day

1....

2

'

3

4

5

6

7 

9....

10 

11 

12 

13 

14 

15 

16 

17 is

19 

20 

21

22

23

24

25

2fi

27

28

29

30

31

October

0.86

4.Q

.42

.32

.25

.21

.16

.16

.17

November

 0.77

1 19

.62

.38

.24

.27

.28

.22

.17

.16

.16

December

0.19

.17

.16

i<*

.08

.08

.11

no

.04

.03

.05

.08

January

0.05

.09

.07

.05

.07

.07

.07

.10

.21

.11

.09

.05

.05

.05

February

0.06

.12

.38

.75

.49

.23

.19

.14

.09

.12

.14

March

0.36

.56

.53

.60

.62

.78

.79

.67

.55

.49

.72

1.57

April

1.22

.98

QO

.67

.64

.68

.52

.47

.35

.31

.30

.31

.24

.28

.36

.41

.56

.60

.72

.90

May

2.11

2.92

2.58

2.26

1.99

1.74

1.49

1.72

1.45

1.93

1.24

1.52

1.28

1.13

1.12

.97

.97

* 1.03

.88

June

1.24

1.28

1.10

.89

1.02

.85

..48

.77

.63

.77

.67

.45

.57

.41

.56

.48

.41

.32

.38

.48

.54

July

0.43

.41

.50

.29

.17

.15

.17

.17

.50

.14

.63

.53

.67

.70

.40

August

0.72

.65

1.13

.43

.38

.40

.45

.47

.28

.62

.79

.57

.41

.32

.34

.35

.23

.57

.50

1.30

1.90

1.88

1.40

September

1.18

1.75

1.02

.71

.93

.76

.70

.69

.45

.34

.31

.24

.20

.18

.44

.26

.16

.16

.10

.10

.09

.09

.06

.06 .07'

.06

.06

.05

.06

1928-29

1

2

3

4

B

f>

7

8 

9

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23...

?4

25 

26

27

?,8

?9

30

31

0.07

.19

.16

.12

.53

.62

.21

1.86

5.76

3.01

1.96

1.58

1.12

.83

.52

.44

0.65

2.28

1.02

.81

.61

.32

.28

.27

.25

.27

.23

.23

.17

.14

0.16

.18

.13

.14

.12

.11

.10

.09

.07

.06

.05

.02

.01

.02

.04

0.07

.06

.05

.04

.04

.02

.06

03

.04

.06

.08

.07

.08

nfi

.05

0.04

.05

18

.15

.11

05

.06

.07

.07

.12

.11

.08

0 19

1^

no

99

2 Q4.

3.28

3.66

1.75

1.26

.92

 .61

.80

1.19

.95

CO

6.95

1.74

4.20

3.26

3.31

2 79

2.07

1.50

1 30

i 93

.96

.80

.79

.77

.89

1 37

2.05

1 Qfi

1.88

1.77

1.65

1.61

1.30

1.20

.96

oo

0.75

.62

.61

.68

.74

.77

.87

Oft

1.18

1.68

1.53

1.27

1 48

1.46

1 ^fl

1.88

1.69

1.26

1.98

1.45

1 98

i 4n

1.30

2.12

1 34.

1 ^3

1.30

.88

1.04

89

.88

1.01

1.08

.92

QQ

1.15

1.03

.91

.87

69

.84

70

.68

64

.62

.77

.68

.61

.57

Af\

.52

ifi

.46

Aft

.52

9O

0.27

.30

.39

.30

.40

.23

.20

.21

.22

.20

1.28

.41

.60

.23

.18

.20

.19

.24

.30

.29

.31

2.52

.64

Kn

.73

7.49

3.12 in Q

8.03

8.85

5.17

7.53

5.70

7 Q4

6.89

4.87

4.38

3.82

4.40

5.30

9.28

5.66

3 91

1.91

1.23

.88

.64

.69

.49

.48

40

.52

31

.36

.39

.40

.42

.51

0.98

2.02

2.80

3.86

5.64

4.95

4.59

5.06

3.81

3.34

2.43

1.62

1.66

1.32

1.39

91

.65

.61

1.09

6.35

8.07

4.81

8.90

6.87

4.24

2.86

2.03

.
30 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily lead of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941

1929

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...

97

28... 

29-.. 

30... 

31..-

October

Mean 

discharge 

(secondfeet)

22,900 

21,600 

20,200

18,900 

17, 700

16,500 

15, 800 

15,200 

15, 100 

14,800

14,500 

14,400 

14,900 

16, 100 

16,700

16, 300 

15,600 

16,800 

16,900 

16,900

15,400 

14, 600 

14,000 

13,300 

12, 700

12,400 

11,900

11,600 

11,300 

11,200 

10,900

Monthly k

Suspended sediment

Mean 

percent

1.57 

1.06

1.00 

.68

.58 

.81 

.45 

.42 

.36

.37 

.31 

.34 

.34 

.41

.39 

.43

.40 

1.37 

1.02

.73

.70 

.58 

.69 

.38

.39

.26 

.22 

.20 

.17

ad (tons).

Tons per

day

970, 000 

618,000 

539, 000 

510, 000 

325, 000

258, 000 

217, 000 

184, 000 

171, 000 

144,000 

145, 000 

120,000 

137,000 

148, 000 

185,000

171,000 

181,000 

181, 000 

624,000 

,485,000

303,000 

276,000 

219, 000 

248,000 

130, 000

130, 000 

83,400 

81,300 

67,000 

60,400 

50,000

7, 941, 000

November

Mean 

discharge 

(secondfeet)

10, 800 

10,800 

10,800 

10,800 

10,800

10, 700 

10, 400 

10,300 

10,600 

10,700

10, 600 

10,800 

10,800 

10, 700 

10,500

10, 200 

10,000 

9,760 

9,320 

8,930

8,950 

9,220 

9,350 

9,320 

9,120

8,890 

8,330 

7,890 

7,480 

7,300

Suspended sediment

Mean 

percent

0.20 

.19

.16 

.17

.16 

.19 

.16 

.18

.17

.13

.14

.Is

.16

.11 

.10 

.13

.13

.11 

.06

.06 

.07

Tons per

day

58,000 

55,000 

46,600 

46,600 

49,500

46,200 

53,300 

44,400 

51, 500 

48,600

48, 600 

37,900 

37,900 

37,500 

39,600

35,800 

35, 100 

34,200 

40,200 

26,500

26,500 

24,900 

32,800 

32,000 

32, 000

26,400 

13,500 

12,800 

12,100 

13,800

1,100,000

December

Mean 

discharge 

(secondfeet)

7,230 

7,410 

7,780 

8,020 

8,340

8,680 

8,840 

8,740 

8,360 

8,280

8,130 

8,130 

8,120 

 8, 170 

8,150'

8,390 

8,450 

8,550 

8,470 

8,330

8,180 

7,890 

7,590 

7,160 

6,450

5,960 

5,580 

4,890 

4,540 

4,370 

4,660

Suspended sediment

Mean 

percent

K&P 

.07

.08 

.11

.11

.14 

.13 

.12 

. .08

.12 

.15 

.12 

.08 

.14

.04

.12

Tons per

 -day'

; S>600 

14,000 

14,700 

17,300 

24,700

25,800 

33,400 

30,600 

27,600 

17,900

26,300 

32,900 

26,300 

17,700 

30,800

15,800 

9,120 

27,700

1930

l--~

2-.~ 

3__- 

4..- 

5. _

6-.-.

7_ 

8----

10-..

11... 

12--. 

13.--

15.-.

16--- 

17-..

18...

19--. 

20--.

21..-

22--.

23-.- 

24... 

25.--.

26-..

27-.-

28..-

29... 

30... 

31---

January

4,900 

5,080 

4,930 

4,880 

4,920

5,340 

5,930 

6,240 

6,360 

6,440

6,700 

6,440 

6,090 

5,780

5,610

5,550 

5,690

5,850

6,030 

5,640

5,340 

4,860

4,160 

3,860 

3,260

3,250

3,200

4,430

4,600 

4,420 

4,360

Monthly 1(

0.04

.04

.04

.04

.04

.03

ad (tons).

6,200

5,260

6,500 

6,390 

6,700 

6,850 

6,700

7,230 

6,700 

6,580 

5,400 

4,530

February

4,710

5,390 

6,480

7,200 

7,200

6,600 

6,380 

6,380 

6,580 

6,810

7,000 

7,120 

7,280 

7,580 

7,890

8,440

9,150 

9,440

9,300 

9,280

9,280 

9,540

10,200

10,700 

11,500

16,500 

14,600

13,800

0.05

.09

.07

.10

.07

.11

.10

.17

.15

.25

.24

.64

1.33

5,400 

7,280 

10,800 

17,500 

13,500

12,500 

13,500 

17,200 

27,000 

14,000

13,200 

13,500 

21,600 

21,500 

21,300

27,000 

42,000 

40,500 

37,600 

40,500

62,600 

64,700 

65,000 

69,300 

80,900

285, 000 

324, 000 

495,000

1, 864, 000

March

13,400 

12, 300 

11,500 

10,800 

10,100

9,540 

9,200 

9,030 

8,760 

8,710

8,950 

9,030 

8,810 

8,490 

8,250

8,170 

8,280 

8,290 

8,550 

8,890

9,810 

10,100 

10,100 

10,300 

11,400

11,400 

11,500 

11,500 

11,400 

11,300 

11,200

0.25 

.19

.20

.20 

.22

.21

.21 

.22 

.20 

.20 

.16

.17 

.16 

.20 

.20 

.42

.38

.40

.46 

.58

.73

.68 

.62 

.68 

.68 

.62

216,000 

82,900 

58,900 

53,900 

54,500

48,500 

49,600 &fm>

48,500 

49,300

50,700 

53,600 

47,500 

45,800 

35,600

37,500 

35,700 

44,700 

46,100 

101,000

101,000 

109,000 

113,000 

125,000 

177,000

224,000 

211,000 

192,000 

209,000 

207,000 

187,000

3,069,000
QUANTITIES OF SUSPENDED SEDIMENT 31

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1930

Day

l..~

2_...

3__-

4

5.--

6.--

7....

8-_-

gML "

11...

12.,.

13...

14...

15..-

16...

17-.-

18.. .

19...

20...

21...

22...

23...

24. .

26. .

26- .

27- -

28. .

29. .

30..-

31

April

Mean 

discharge 

(secondfeet)

10,900,

10,600

9,910

9,SOO

9,600

9,640

9,440

10,300

11,300

13,800

21,000

30,100

39,100

40,200

39,100

40,100

40,300

41, 100

39,600

36,900

33,100

30,100

28,600

29,300

34,400

39,200

42, 100

, 44,400

44,600

44,000

Monthly 1

Suspended sediment

Mean 

percent

0.55

.49

.46

.29

.32

.49

.68

.74

1.97

1.99

2.94

2.63

2.78

3.38

1.71

1.47

1.86

2.09

.84

.89

1.08

.69

1.06

1.22

1.04

1.27

1.26

.87

jad (tons) -

Tons per 

day

W2.000

140,000

123, 000

80,900

97,400

74,600

81,500

136,000

207,000

275,000

1, 120, 000

1, 620, 000

3, 100, 000

2, 850, 000

2, 930, 000

3,660,000

1,860,000

1,630,000

1.990,000

2,080,000

750,000

723,000

833,000

545,000

983,000

1,290,000

1, 180, 000

1, 520, 000

1,520,000

1,030,000

34, 590, 000

May

Mean 

discharge 

(seeondJeet)

44,100

42,200

39,300

36,900

07 Kf\f\ Off uvw

40,900

41,400

38,600

36,000

33,700

31,300

29,600

27,600

25,800

24,200

22,800

21,500

20,600

21,400

24,400

25,800

25,400

24,900

25,400

32,100

37,000

34,300

34,200

38,000

42,600

48,300

Suspended sediment

Mean 

percent

1.10

1.07

.80

.85

.75

.86

.79

.64

.58

.50

.47

.40

.37

.44

.43

.42

.30

.30

.29

.54

.62

.58

.50

.45

.74

.89

.78

.78

.63

.67

1.03

Tons per 

day

1,310,000

1,220,000

848,000

846,000

759,000

949,000

882,000

665,000

563,000

454,000

397,000

319,000

275,000

306,000

281,000

258,000

174,000

167,000

167,000

355,000

431,000

397,000

336,000

308,000

641,000

883,000

722,000

719,000

646,000

770,000

1,340,000

18, 390, 000

June

Mean 

discharge 

(secondfeet)

54,800

65,900

69,000

67,400

60,500

54,800

49,800

46,200

46,200

49,800

53,600

55, (JOO

55, 600

55,200

57,900

61,600

61,400

58,500

55,700

53,800

51.600

50,680

47,500

44,700

43,400

42,600

40,000

36,000

32,200

29,200

Suspended sediment

Mean 

percent

1.09

1.28

1.21

1.17

1.20

.84

.87

.67

.61

.84

.66

.54

.74

.69

.68

.66

.57

.64

.45

.46

.54

.53

.81

.48

.44

.47

.43

.39

.30

Tons per 

day

1, 610, 000

2, 280, 000

2,250,000

2,130,000

1,960,000

1,240,000

1,170,000

835,000

809,000

819,000

1,210,000

990,000

808,000

1,100,000

1,080,000

1,130,000

1,080,000

899,000

961,000

653,000

640,000

737, .000

679,000

976,000

562,000

604,000

507,000

417,000

339,000

236,000

30, 610, 000

1930

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...

July

26,600

24,900

23,200

21,500

11,180

18,000

16,600

15,300

14,600

14,100

14,000

13,200

15,700

24,400

19,600

16,700

16,900

15,400

16,900

25,200

22,800

21,100

19,600

21,600

21,900

19,700

17,900

16,500

15,600

15,400

18,100

0.32

.23

.32

.20

.20

.22

.18

.20

.20

.19

.27

.25

2.25

5.33

4.19

3.28

2.20

2.32

1.81

2.76

2.93

2.38

3.36

2.81

2.34

2.16

1.42

1.18

1.12

1.38

Monthly load (tons).

230,000

154,000

200,000

116,000

106,000

107,000

80,100

82,600

78,800

72,300

102,000

89,000

953,000

3, 510, 000

2,200,000

1,480,000

1,000,000

964,000

825,000

1, 880, 000

1,620,000

1, 670, 000

1, 260, 000

1, 960, 000

1, 660, 000

1,240,000

1,040,000

632,000

496,000

465,000

674,000

26, 950, 000

August

17,600

18,100

17,800

19,000

23,000

24,100

28,100

21,400

27,300

30,000

44,400

54,800

47,900

43,300

35,900

34,700

29,300

27.600

29,500

32,900

30,000

25,400

22,200

20,100

18,200

16,400

14,600

13,600

12,500

12,100

11,200

2.01

3.03

2.41

2.83

4.47

3.40

3.36

3.10

6.64

8.45

10.3

10.7

6.89

6.41

8.64

5.46

3.98

3.31

3.48

3.09

- 2.72

2.36

2.33

1.77

1.49

1.21

1.03

.91

.60

.60

.45

963,000

1, 480, 000

1, 160, 000

1, 450, 000

2,770,000

2, 210, 000

2, 550, 000

1, 790, 000

4, 890, 000

6, 840, 000

12, 300, 000

15, 800, 000

8, 910, 000

7,490,000

8,360,000

5,110,000

3,150,000

2, 460, 000

2,770,000

2, 740, 000

2,200,000

1,620,000

1,400,000

960,000

731,000

535,000

406,000

331,000

202,000

196,000

136,000

103,900,000

September

10,200

9,680

8,360

9,370

10,200

9,830

10,000

13,500

14,500

14,000

13,300

11,200

9,860

9,050

8,470

8,090

7,760

7,400

7,120

6,980

6,840

6,550

6,320

6,170

6,070

6,160

6,830

6,860

6,720

9,030

0.46

.42

.36

.31

.29

.29

.88

1.83

1.88

1.48

2.55

1.19

.93

1.08

.71

.68

.44

.46

.39

.29

.22

.17

.16

.14

.13

.15

.15

.14

.33

127,000

U3>000

106,000

91,000

85,300

76,900

78,200

320,000

716,000

710,000

531,000

770,000

316,000

227,000

247,000

155,000

142,000

87,800

88,300

73,400

53,600

38,900

29,000

26,600

22,900

21,600

27,600

27,800

25,400

80,400

5,415,000
32 SEDIMENT IN COLORADO -RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 30, 1941 Continued

1930

Day

1-...

2....

3....

4_...

5..-

«...-

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...

October

Mean 

discharge 

(secondfeet)

9,830

9,540

8,920

10,600

10,300

10,800

10,000

9,710

9,220

8,850

8,550

8,530

8,550

8,810

8,820

8,730

9,030

9,340

9,120

9,060

9,100

9,330

9,480

9,530

9,380

9,160

8,970

8,730

8,570

8,430

8,300

Suspended sediment

Mean 

percent

0.53

1.31

.89

.66

.88

.94

' .80

.91

.79

.73

.75

.66

.49

.48

.44

.35

.30

.38

. .36

.30

.33

.32

.32

.32

.30

.32

.28

.23

.21

.18

.18

Monthly load (tons)..

Tons per 

day

141,000

337,000

214,000

189,000

244,000

274,000

216,000

238,000

196,000

174,000

173,000

152, 000

113,000

114, 000

105.000

82,400

73,100

95,700

88,500

73,300

81,000

80,500

81,800

82,300

75,900

79,000

67,700

54,200

48,500

40,900

40,300

4, 025, 000

November

Mean 

discharge 

(secondfeet)

8,210

8,040

8,060

7,950

7,770

7,580

7,530

7,410

7,420

7,470

7,420

7,300

7,180

7,160

7,020

6,990

7,100

7,280

9,690

. 8,830

8,190

8,430

8,190

8,010

7,880

7,520

6,820

5,950

5,390

4,990

Suspended sediment

Mean 

percent

0.22

.24

.19

1.18

.16

.16

.15

.16

.14

.19

.15

.16

.15

1.12

.27

1.10

i.lO

.14

.43

.68

.45

.37

L20

.25

.28

1.20

1.17

.17

1.10

.09

Tons per 

day

48,700

52,100

41,300

38,600

33,500

32,700

30,500

32,000

28,000

38,300

30,000

31,500

29,000

23,200

51,100

18,900

19,100

27,500

112,000

162,000

99,400

84,100

44,200

54,000

59,500

40,600

31,300

27,300

14, 500

12,100

1,347,000

December

Mean 

discharge 

(secondfeet)

4,910

5,140

5,840

5,930

5,950

5,900

5,730

5,510

5,560

5,600

5,550

5,590

5,690

5,690

5,680

5,650

5,700

5,610

5,570

5,470

5,310

5,200

4,850

4,510

3,980

3,680

3,780

3,580

3,480

3,450

3,600

Suspended sediment

Mean 

percent

10.09

.10

1.15

.40

.28

1.22

1.18

.19

1.13

.11

i.lO

i.lO

.09

1.10

.11

1.09

.08

1.08

1.08

.09

1.08

.07

1.06

.06

1.06

.05

-1.05

1.04

.04

1.04

.04

Tons per 

day

11,900

13,900

23,600

64,000

44,900

35,000

27,800

28,200

19,500

16,600

15,000

15,100

13,800

15,300

16,900

13,700

12,300

12,100

12,000

13,300

11,500

9,820

7,850

7,310

6,450

4,960

5,100

3,860

3,750

3,720

3,880

493,100

1931

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...

January

3,580

3,550

3,660

3,860

4,070

4,080

4,200

4,210

4,420

4,620

4,570

4,530

4,500

4,400

4,560

4,790

4,870

4,980

4,900

4,830

4,860

4,740

4,690

4,760

4,980

4,880

4,920

4,950

4,920

5,080

5,220

10.04

.04

1.04

1.04

.04

1.05

.«7

1.06

.06

1.05

.05

1.04

1.04

.03

1.03

1.04

.04

1.04

.04

1.03

.03

1.03

1.03

.03

i.03

.07

1.07

.08

1.08

.10

i.lO

Monthly load (tons)..

3,860

3,830

3,940

4,150

4,400

5,500

7,930

6,820

7,150

6,230

6,150

4,880

4,850

3,560

3,690

5,180

5,260

5,370

5,290

3,910

3,940

3,830

3,800

3,860

4,020

9,220

9,280

10, 700

10,600

13,700

14,100

189,000

February

5, 420 1

5,600

5,840

6,770

6,780

6,890

6,840

6,790

6,960

6,980

6,790

6,700

6,920

6,980

7,080

7,500

8,100

9,020

8,700

8,070 **7,560

7,020

6,750

6,570

6,530

6,540

6,330

6,260

10.10

.10

1.15

.22

.20

.19

.20

1.19

.18

.19

.15

.16

.16

.20

1 .28

1.25

.26

1.26

1.03

.74

.67

.54

.38

.26

1.20

.19

.19

.17

14,600

15,100

23,600

40,200

36,600

35,300

36,900

34,800

33,800

35,800

27,500

28,900

29,900

37,700

53,500

50,600

56,800

307,000

242,000

161,000

137,000

102,000

69, 200

46,100

35,200

33,500

32,400

28,700

1, 786, 000

March

6,230

6,160

6,050

6,050

6,110

6,160

6,190

6,160

6,250

6,500

6,740

6,810

6,650

6,470

6,150

6,150

6,530

6,950

7,650

7,900

8,120

8,380

8,380

8,460

8,540

8,690

8,970

9,360

9,740

9,760

9,550

10.14

1.13

.11

i.lO

.11

1.12

.12,

i.M

.10

1.12

.24

1.22

.20

1.17

L14

.13

.16

.24

.36

.39

.52

.68

.62

.52

.48

.54

.57

.60

.66

.60

.65

23,500

21,600

18,000

16,300

18,100

19,900

20,000

14600

16,900

21,000

43,600

40,400

35,900

29,700

23,200

21,600

28,200

45,000

74,300

83,100

114,000

154,000

140,000

119,000

111,000

127,000

138,000

151,000

173,000

158,000

167,000

2, 169, 000

i Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 33

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of sus- 

. pended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1931

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

Mean 

discharge 

(secondfeet)

9,160

8,640

7,960

7,520

7,000

6,650

6,910

7,050

7,170

7,200

7,100

7,440

7,830

7,840

7, 860

7,920

8,510

9,640

10,500

10,900

11,600

11,400

11,200

11,900

12,800

13,000

13,600,

13,800

14,800

15,100

Suspended sediment

Mean 

percent

0.65 i.50

1.40

.38

1.33

.31

i.30

.31

1.30

i.29

.27

1.28

.30

1.30

.36

1.43

1.50

.51

.73

.75

.74

.86

.72

.66

.81

.70

.70

.74

.92

.80

Monthly load (tons) _

Tons per 

day

161,000

117,000

85,900

77,100

62,300

55,600

55,900

59,000

58,000

56,300

51,700

56,200

63,400

63,400

76,300

91,900

115,000

133, 000

207,000

220,000

232,000

264,000

217,000

212,600

280,000

245, 000

257,000

275,000

367,000

326,000

4, 541, 000

May

Mean 

discharge 

(secondfeet)

13, 300

13, 500

13,000

12,600

12,800

13,000

13,400

14,300

15,900

16,000

15,800

17,700

18,300

17,100

16,000

15,600

14,900

14, 700

15,900

21,400

29,000

33,800

31, 300

27,800

24,400

21,000

19,000

19, 100

23,200

26,700

26,900

Suspended sediment

Mean 

percent

0.85

.80

.95

.77

.82

.88

.72

.96

.99

.93

.83

.96

.89

.93

.76

.72

.77

.71

.76

1.16

1.51

1.68

1.83

1.45

1.14

1.07

.87

.90

1.03

1.01

.P8

Tons per 

day

305, 000

291,000

333,000

262,000

283,000

309,000

260,000

370,000

425, 000

401,000

354, 000

458,000

439,000

429,000

328,000

303,000

309, 000

281, 000

326,000

670,000

1,180,000

1, 530, 000

1, 540, 000

1,090,000

750,000

606,000

446,000

464,000

644,000

727,000

711,000

16,820,000

June

Mean 

discharge 

(secondfeet)

26,200

25,100

24,400

24,900

26,800

28,700

29,800

30, 100

29,300

30,500

31,900

31,600

29,800

27,500

25,400

24,000

23,500

23, 100

23,100

23,600

23,600

22,000

30,200

18,600

17,300

15,900

14,500

13,700

13,300

12,900

Suspended sediment

Mean 

percent

0.95

.80

.85

.68

.97

.94

.84

.86

.68

.54

.86

.90

.70

.71

.62

.64

.67

.50

.56

.70

.54

.47

.32

.38

.34

.34

.29

.24

.29

.24

Tons per 

day

671,000

542,000

559, 000

457, 000

701, 000

728,000

675, 000

698,000

537,000

444,000

740,000

767, 000

563,000

527, 000

425,000

414,000

425,000

312,000

349,000

446,000

344,000

279,000

174,000

191,000

159,000

146,000

113,000

88,700

104,000

83,500

12, 660, 000

1931

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...

July

12,600

12,900

13,100

13,600

14,900

17,700

15,900

14,500

12, 700

_ 11,600

10,400

9,290

8,340

7,460

6,760

6, -ISO

5,770

5,290

4,910

5,200

4,750

5,040

4,690

3,980

3,600

3,480

3,620

3,600

3,680

3,350

5,160

10.10

.23

.24

.27

.42

.88-

.93

1.12

.90

.63

.40

.37

.31

.22

.16

.13

i.ll

.09

i.ll

.13

.61

1.23

2.86

1.22

.70

1.42

.32

.27

.75

2.25

.70

Monthly load (tons) .

34,000

80,000

84,800

99,000

169,000

420,000

399,000

438,000

308,000

197, 000

112,000

92,700

69,700

44, 300

29,200

21,700

17,100

12,800

14,600

18,200

78,200

167,000

362,000

131, 000

68,000

39,400

31,200

26,200

74,400

203,000

97,400

3, 939, 000

August

5,640

8,400

7, 830

7,860

8,860

7,470

6,930

8,090

7,380

6,190

6,500

7,290

5,980

5,380

5,570

5,270

4,960

4,720

4,140

3,880

3,640

3.350

3,180

3,070

3,460

3,400

3,190

2,940

2,900

2,940

3,240

6.35

3.14

15.06

3.88

3.48

4.75

3.40

5.39

4.54

3.30

2.06

3.58

2.50

2.02

1.28

1.00

.88

1.67

1.95

1.14

.83

.78

.62

.46

.86

1.87

1.42

.83

.59

.55

.32

966,000

711,000

1, 070, 000

823, 000

832,000

957,000

635,000

1,180,000

904,000

551,000

361, 000

704, 000

403,000

293,000

192, 000

142,000

118,000

213, 000

218, 000

119,000

81,500

70,500

53,200

38,100

80,300

171,000

122,000

65,800

46,100

43,600

28,000

12, 190, 000

September

3,220

3,110

3,200

2,930

2,720

2,780

3,120

2,930

2,680

2,580

2,870

2,700

2,560

2,630

2,840

3,140

2,750

3,440

4,610

3,290

4,920

5,460

5,630

5,810

8,710

12,400

15,400

12,600

10,900

8,850

10.65

.47

.36

.67

.67

.40

.28

.20

.22

.15

.21

1.24

.73

.53

.39

.87

1.83

.77

1.08

1.69

2.61

2.25

2.85

3.58

2.70

4.01

3.54

3.32

2.34

2.48

56,400

39,400

31,100

52,900

49,100

30,000

23,600

15,300

15,900

10,400

16,300

90,300

50,400

37,600

29,900

73, 700

136,000

71,400

134,000

150,000

346,000

331,000

433,000

561,000

634,000

1,340,000

1,470,000

1, 130, 000

688,000

592,000

8, 639, 000

1 Estimated.
34 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, -and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1931

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...

October

Mean 

discharge 

(secondfeet)

7,910

7,470

7,730

15,300

15, 900

18,200 

13,900

10, 800

9,230

8,390

7,670

7,340

7,970

7,440

6,860

6,410

6,290

6,010

5,800

6,010

7,500

13,300

11,200

9,230

7,800

6,820

6,550

6,480

6,170

6,030

5,920

Monthly IOE

Suspended sediment

Mean 

percent

2.27

12.50

12.40

2.90

6.17

5.24 

2.98

2.88

12.30

1.79

1.54

1.17

1.12

1.11

.81

1.07

.85

.60

.36

.46

.39

1.78

2.38

2.14

1.71

1.79

11.20

1.19

1.03

.61

.62

d (tons)-.

Tons per 

day

484, 000

504,000

500,000

1, 200, 000

2, 650, 000

2, 570, 000 

1, 120, 000

839,000

573, 000

405,000

319, 000

232,000

241,000

223,000

150,000

185, 000

144, 000

97, 300

56,300

74,600

78,900

638,000

719,000

533,000

360,000

329, 000

212, 000

208,000

171, 000

99,200

99,000

16, 010, 000

November

Mean 

discharge 

(secondfeet)

5,880

5,760

5,820

6,090

6,010

5,810 

5,810

5,740

5,690

6,030

6,160

6,520

7,960

9,950

10,500

10, 300

8,670

7,310

6,830

6,650

6,500

6,680

6,440

6,310

6,290

6,100

5,600

4,860

4,390

4,020

---.-----..

Suspended sediment

Mean 

percent

10.40

.36 i.35

.31

.28

.25 

.22

1.21

.21

1.23

.26

1.35

.35

3.25

2.01

2.28

1.68

»1.30

'.7798

.81

1.75

.50

.30 1.28

1.26

1.25

.24 1.18

.12

----------

Tons per 

day

63,400

55,900

54,900

50,900

45,400

39,200 

34, 500, '

32,500

32,200

37,400

43,200

61,500

75,100

872,000

569,000

633,000

393,000

256,000

181,000

138,300

142,000

135, 000

86,800

51, 100

47,500

42,800

37,800

31,400

21,300

13,000

1 4,277,000

December

Mean 

discharge 

(secondfeet)

3,710

4,160

4,740

4,600

4,610

4,430 

4,010

3,530

3,720

3,910

4,130

4,000

5,550

5,620

5,170

4,950

4,560

4,080

3,150

2,520

2,160

2,560

2,850

3,430

4,740

4,900

5,330

6,200

6,550

6,900

7,010

.-.._......

Suspended sediment

Mean 

percent

10.10 i.l2

i.l5

.22 i.l6

1.12 

.12

MO

.08

1.08

1.08

.09

1.15

.23

1.27

.17

1.12

1.11

.06

1.05

1.05

.07

1.06

.06

1.07

.18 1.21

1.24

.26

1.28

.30

.-.--.-.-..

Tons per 

day

10,000

13,500

19,200

27,300

19,900

14, 300. 

13, Oft)

9,520

8,040

8,440

8,900

9,710

22,400

34,900

37,700

22,700

14,800

12,100

5,100

3,400

2,910

4,830

4,610

5,560

8,950

23,800

30,200

40,100

45,900

51,900

56,700

590,400

1932

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--.

January

7,160

6,170

5,680 

5,410

5,230

5,190

4,970

4,620

4,450

4,770

4,730

5,040

5,130

5,410

5,450

5,380

5,270

5,010

4,910

4,900

4,830

4,610

4,600

4,680

4,450

4,220

4,320

4,470

4,490

4,700

4,360

10.24

i.26

1.22 

.18 1.12

.15

1.10

1.08

.12 i.ll

.11 1.13

.15

1.13

1.14

.14

1.13

.15

1.13

.10

1.10

1.10

.10 1.10

.10

1.08

.08 1.10

1.10

.18 1.08

Monthly load (tons)

46,300

43, 300

33, 700 

26, 300

16, 900

21, 000

13, 400

9,980

14, 400

14,200

14, 000

17, 700

20,800

19, 000

20,600

20,300

18,500

21, 900

17,200

13,200

13,000

12, 400

12, 400

12,600

12,000

9,120

9,330

12, 100

12, 100

22, 800

9,410

559. 000

February

4,170

4,190

4,380 

4,830

5,810

6,450

7,120

6,720

9,310

23,600

45, 900

33,000

23,800

22, 700

17, 300

14,200

12, 100

11,200

10,900

10, 600

9,700

10, 700

10,300

10,200

9,800

9,650

9,670

9,650

10,600

0.10

i.OS

1.10 

.14

1.30

.57

.61

11.00

1.44

4.47

8.12

5.68

4.95

3.48

2.35

1.82

1.44

1.07

11.00

.94

.81

.91

.78

.93

.76

.85

.85

1.84

.92

11,200

9,040

'11,800 

18,200

47,000

99,100

117,000

181,000

362,000

2,850,000

10,100,000

5, 060, 000

3, 180, 000

2,130,000

1,100,000

697,000

470, 000

323,000

294,000

269,000

212,000

263,000

217, 000

256,000

201,000

221,000

222, 000

219,000

263,000

29, 400, 000

12,100

13, 300

15, 200 

16, 100

16, 300

14,400

12,200

10,600

9,670

9,580

10,900

12,500

13, 300

12, 800

11,500

10,700

10,200

10, 100

10, 700

11,000

12,500

14,400

15,900

17,300

19,200

18, 600

17,700

18,400

17, 900

16, 700

15,800

March

1.28

11.30

2.18 

2.20

2.36

2.04

1.72

1.24

.98

.95

' .99

1.13

1.23

1.04

1.06

.87

.71

.69

.71

.80

1.03

1.46

1.50

1.78

2.42

1.85

1.55

1.76

1.90

1.49

1.49

.. ..--..--.. 

418,000

466,000

894,000 

955, OTO

1,040,000

792,000

566,000

354,000

256,000

245,000

291,000

381,000

441,000

359,000

329,000

251,000

195, 000

188,000

205,000

237,000

347,000

567,000

643,000

831,000

1, 250, 000

928,000

740,000

873,000

917,000

671,000

635,000

17,260,000

Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 35

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 30, 1941 Continued

1932

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

Mean 

discharge 

(secondfeet)

15,700

15,300

14,300

15,900

18,500

20,400

23,300

29,200

31,400

29,100

26,700

26,300

24,800

23,800

24,800

27,600

32,100

32,400

34,500

38,200

39,200

38,600

40,100

40,500

39,400

36, 700

33,900

32,000

32,300

32, 100

Monthly ]

Suspended sediment

Mean 

percent

1.37

1.16

J 1.10

1.10

1.41

1.75

2.26

2.63

12.00

2.52

1.97

1.94

1.73

1.72

1.77

1.53

1.56

1.83

1.28

1.71

1.65

1.66

1.64

1.45

1.69

1.38

1.70

1.04

1.12

.98

oad (tons)

Tons per 

. day

580,000

479, 000

424, 000

472,000

704, 000

963,000

1, 420, 000

2, 070, 000

1, 690, 000

1,980,000

1,420,000

1,380,000

1, 160, 000

1,100,000

1, 180, 000

1, 140, 000

1, 350, 000

1,600,000

1,190,000

1, 760, 000

1, 740, 000

1,730,000

1,770,000

1,580,000

1,800,000

1, 370, 000

1,550,000

898,000

976,000

848,000

38,320,000

May

Mean 

discharge 

(secondfeet)

29, 700

27,000

27,200

29,300

32,000

37, 100

43.500

45,900

46, 100

44,300

44,000

45,200

47, 700

52, 100

58,800

68,000

74,400

79,700

83,500

85,900

91,800

94,000

91,600

90,300

97,500

101, 000

99,100

95,900

89,400

78,400 

70, 700

Suspended sediment

Mean 

percent

1.04

.83

.92

.80

.98

1.14

1.48

1.19

1.30

1.24

L04

1.21

1.02

1.21

1.08

1.16

1.27

1.66

1.42

1.49

1.35

1.45

1.26

1.28

1.41

.76

1.13

1.13

1.04

.95 

1.90

Tons per 

day

833,000

604,000

675.000

632,000

846,000

1, 140, 000

1,740,000

1,470,000

1, 620, 000

1, 480, 000

1,230,000

1,480,000

1, 310, 000

1, 700, 000

1, 710, 000

2, 130, 000

2, 550, 000

3, 570, 000

3, 200, 000

3,450,000

3, 340, 000

3,680,000

3, 110, 000

3,120,000

3,710,000

2,070,000

3, 020, 000

2, 920, 000

2,510,000

2,010,000 

1, 720, 000

64, 580, 000

N June

Mean 

discharge 

(secondfeet)

66,900

66,800

62, 700

58,600

57,200

56,100

55,200

54,300

52, 100

49,900

50,200

51,800

53,600

54,000

54,900

57,700

62,700

64,000

67,000

67,900

66,500

63,000

62, 100

63,100

63,400

65,900

67,800

69,700

71,200

68,600

Suspended sediment

Mean 

percent

0.89

.79

.75

.80

.64

.56

.57

.63

.62

.51

.53

.46

i .40

.51

.46

.43

.54

.56

.61

.43

.74

.55

.62

.48

.39

.55

.43

.41

.45

.50

Tons per 

day

1,610,000

1,420,000

1,270,000

1,260,000

987,000

847,000

849,000

923,000

871,000

686,000

718,000

643,000

578, 000

743,000

681,000

669,000

913,000

967,000

1, 100, 000

787,000

1,330,000

935,000

1,040,000

817,000

667,000

978,000

786,000

771,000

864,000

925,000

27,640,000

1932

!-._.

2L___

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...

July

65, 300

62,200

59, 700

57,200

54,500

50,500

47,200

44,800

41,200

36,900

33,900

31,100

31,000

39,000

34,100

33,400

30,800

27,900

25,500

24,500

24,000

23,900

23,300

21,600

19,500

17,900

16, 700

15,500

14,800

15, 700

18,300

Monthly

a 39

.49

.43

.42

.41

.54

.35

.41

.33

.29

.28

.27

.28

1.67

1.55

1.40

11.20

.97

.79

,64

.56

.44

.44

.47

.26

.28

.27

.22

.16

.20

1.55

oad (tons)

687,000

822,000

692,000

648.000

603,000

735,000

446,000

495,000

367,000

289,000

256,000

226,000

234,000

1,760,000

1, 420, 000

1, 260, 000

997,000

730,000

543,000

423,000

362,000

284,000

276,000

274,000

137,000

135,000

122,000

92,000

63,900

84,700

271,000

15,730,000

August

18,600

16,200

18, 100

20,100

19,300

17,400

16,500

15,000

13,500

13,000

11,800

10,700

9,940

9,100

8,440

7,940

7,500

7,150

6,750

7,000

7,620

8,650

16,100

17,200

13,600

11,400

11,500

18,600

32, 100

49,800

43,900

0.96

.99

U. SO

1.32

1.00

.72

1.64

.59

.39

.42

.52

1.40

.29

1.35

.36

1.23

.16

i.ll

.10

1.08

.09

.35

.99

2.69

4.94

3.76

2.15

2.13

5.95

7.49

5.93

_- -__ .

482,000

433,000

879,000

716,000

521,000

338,000

285,000

239,000

142,000

147,000

165,000

115,000

77,800

85,900

81,900

49,200

32,400

21,200

18,200

15, 100

18,500

81,700

430,000

1,250,000

1, 810, 000

1, 160, 000

667,000

1,070,000

5, 150, 000

10,100,000

7,020,000

33, 600, 000

September

31,200

20,600

17,300

14,800

12,800

11,500

10,800

10,000

9,380

8,920

8,380

7,870

7,360

6,790

6,480

6,170

5,940

5,630

5,430

5,200

5,090

4,960

4,810

4,690

5,120

6,240

9,000

6,970

6,280

6,870

----------

5.82

14.00

3.37

2.70

2.17

1.31

.92

.91

1.07

.80

1.80

.60

1.44

.29

1.23

.20

.23

1.22

.24

 1.18

.16

1.12

1.12

.18

1.15

.15

.62

.69

1.02

1.63

... _ ....

4,900,000

2,220,000

1,570,000

1,080,000

749,000

406,000

268,000

245,000

270,000

192,000

181,000

127,000

90,000

53,100

40,200

33,300

36,800

33,400

35,100

25,200

22,000

16,000

15,600

22,800

20,700

25,200

150,000

130,000

173,000

302,000

13, 430, 000

Estimated.
36 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1932

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...

October

Mean 

discharge (second-^ 

feet)

6,660

5,960

5,830

5,540

5,520

5,410

5,180

5,140

5,080

5,050

4,970

5,040

5,150

5,010

5,080

5,090

5,210

5,220

5,230

5,540

5,610

5,990

5,920

6,180

6,340

7,070

6,770

7,110

6,970

6,910

6.950

Suspended sediment

Mean 

percent

1.24

1.11

1.03

.73

.58

.39

.34

.26

.22

.17

.14

.14

.13

.23

.26

.20

.17

.18

.17

».16

."14

.29

.50

.23

1.05

.52

.33

.27

".27

.27

.21

Tons per 

day

223.000

178,000

162, 000

109,000

86,400

56,900

47,500

36,000

30,200

23,100

18,800

19,000

18,000

31,100

35,600

27,500

23,900

25,400

24,000

23,900

21,200

46,800

79,800

38,300

180,000

99,100

60,300

51,800

50,800

50,300

39,400

Monthly load (tons). 1,917,000

November

Mean 

discharge 

(secondfeet)

6,900

6,810

6,900

6,970

7,020

7,010

6,860

6,650

6,670

6,770

6,810

6,730

6,590

6,550

6,490

6,510

6,550

6,370

6,180

6,240

6,490

6,670

, 6,520

6,670

6,660

6,670

6,530

6,660

6,630

6,460

Suspended sediment

Mean 

percent

10.18

.17 1.17

.17

.15

».14

.13

.13

.13

.11

.10

.10

.10

.10

.10

.10

.10

.10

.09

.09

09

.10

.09

1.10

.10

.09

i.08

.08

.12

.11

Tons per 

day

33,500

31, 200

31,600

32,000

28,400

26,500

24,100

23,300

23,400

20,100

18,400

18,200

17,800

17,700

17,500

17,600

17,700

17,200

15,000

15, 2W

15,800

18,000

15,800

18,000

18,000

16,200

14,100

14,400

21,500

19,200

617,400

December

Mean 

discharge 

(second- 

.feet)

6,310

6,250

6,300

6,460

6,560

6,730

6,550

6,440

6,390

6,170

6,250

6,090

5,700

5,430

5,060

4,460

3,760

3,400

3,180

2,790

3,030

3,370

3,900

4,080

4,140

3,930

3,730

3,660

3,700

3,610

3,300

Suspended sediment

Mean 

percent

10.15

.19

.17 1.17

.17

.14

.17

.11

.11

.11

i.ll

.11

.10

.10

.09

1.08

.07 1.06

.05

.05

.05

.06

.04

.04 1.04

.04

.04

.04

.04

.04

.04

Tons per 

day

25,500

32,000

28,900

29,600

30, 100»

25,400

30,000

19,100

19,000

18,300

18,600

18,100

15,400

14,600

12,300

9,630

7,090

5,500

4,290

3,780

4,100

5,450

4,210

4,400

4,480

4,230

4,020

3,940

3,990

3,880

3,560

413,400

1933

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---

January

2,880

3,990

3,340

3,240

3,340

4,090

3,480

3,690

3,340

3,490

3,730

4,280

4,890

5,180

4,760

4,820

4,980

5,210

5,190

5,000

5,120

5,150

5,240

5,470

5,610

5,560

5,640

5,650

5,620

5,480

5,490

10.04

.03

1.03

.03

.04

1.04

.03 1.03

1.02

.02

1.02

.02

1.06

.07 1.08

.09 i.ll

.14

.04 1.04

.05 1.05

.05 1.06

.07

1.07

.07 1.07

i.07

.07 1.06

Monthly load (tons).

3,100

3,240

2,700

2,600

3,610

4,420

2,800

2,990

1,810

1,890

2,020

2,320

7,900

9.790

10,300

11,700

14,800

19,700

5.610

5,390

6,900

6,960

7,070

8,850

10,600

10,500

10,700

10, 700 in finft lv, OUU

10,400

8870

220.800

February

5,470

5,480

5,450

5,140

5,060

5,020

4,930

4,710

4,320

3,980

2,720

2,910

4,510

4,090

4,530

4,610

4,650

4,950

5,130

5,220

5,490

5,740

5,830

5,910

5,830

5,760

5,880

6,180

0.05

.05

1.05

.05 1.05

.05

.04

.04

.03

.03

.02

.02

.04

.03

.03

.03

.03

.03 1.04

.04

.05

.06

.07

.07

.07

1.07

.07

.08

7,390

7,390

7,340

6,930

6,820

6,770

5,310

5,070

3,510

3,210

1,460

1,560

4,850

3,320

3,670

3,720

3,780

3,990

5,530

5,640

7,390

9,280

11,000

11,200

11,000

10.900

11,100

13,300

182,400

March

8,390

8,310

8,250

8,600

8,570

8,410

8,240

7,950

7,920

7,840

7,780

7,720

8,340

8,520

9,390

10,100

9,960

9,550

9,870

10,400

9,700

9,290

9,110

8,870

9,210

8,780

8,240

'7,860

7,480

7,070

7,120

1.69

.94

.71

1.68

.65

.51

.42

.31

.32

.36

.36

.38

.43

.44

.49

.90

.69

.53

i .49

.45

.42

.42

.38

.40

.39

.36

.31

.34

.32

.33

' .33

382,000

211,000

158,000

158,000

150,000

116,000

93,300

66,500

68,300

76,100

75,500

79, 100

96,700

101,000

124,000

245,000

185,000

137,000

130,000

126,000

110,000

105,000

93,400

95,700

96,900

85,300

68,900

72,100

64,600

62,900

63,400

3,697,000

' Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 37

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1933

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

Mean 

discharge 

(secondfeet)

7,360

7,830

8,000

8,280

8,460

8,940

9,320

9,940

10,400

10,600

10,300

10,200

9,940

9,890

' 9,550

9,060

8,500

8,070

' 7, 710

7,360

6,910

6,870

6,830

7,360

7,950

8,160

9,340

10,300

9,730

9,310

Monthly It

Suspended sediment

Mean 

percent

0.41

.39

.39 1.39

.39

.35

.51

.56

.56

.62

.44

1.50

.47

.36

.38

.35

.36

.35

.30

.29

.25

.23

.22

.20

.25

.31

.34

.41

.42

.33

ad (tons)

Tons per 

day

81,400

82,400

84,100

87, 100

89,000

84,400

128,000

150,000

157,000

177, 000

122, 000

138,000

126,000

96,000

97, 900

85,500

82, 500

76,200

62,400

57,600

46,600

42,600

40,500

43,700

53,600

68,200

85, 700

114,000

110, 000

82,900

2, 752, 000

May

Mean 

discharge 

(secondfeet)

9,220

11,600

12,900

15,600

18,000

18,800

18,000

17,000

17,100

17,000

17,400

17,700

17,800

17,200

15,800

14,700

13,800

12,900

12,200

if; 400

11,000

18,500

28,500

37,500

44,600

44,500

41,100

39,400

39,100

42,500

48,100

Suspended sediment

Mean 

percent

0.35

.88

.75

1.75

1.48

1.40

1.40

1.36

1.19

1.06

1.00

.86

.94

.91

.63

.64

.50

.42

.39

.33

.37

.97

1.72

2.53

2.94

2.50

1.76

1.62

1.47

1.31

1.32

_--- __.--

Tons per 

day

87, 000

275, 000

261,000

736,000

718, 000

710,000

680, 000

624,000

549,000

486, 000

469,000

411, 000

451, 000

422,000

268,000

254,000

186,000

146,000

128, 000

101, 000

110,000

484,000

1,320,000

2, 560, 000

3,540,000

3,000,000

1, 950, 000

1, 720, 000

1, 550, 000

1,500,000

1, 710, 000

27, 410, 000

June

Mean 

discharge 

(secondfeet)

54,700

62,700

69,500

75,800

80,000

78,800

76,400

78,600

77,400

73,700

67, 500

64,900

68,500

75,300

77,000

76,600

73, 700

72,600

7?, 400

71,400

69,700

69,000

67,200

63,000

59,400

54,500

49,600

44,700

40,800

37,600

.... __ ....

Suspended sediment

Mean 

percent

1.58

1.51

1.35

1.42

1.10

1.02

1.14

1.22

1.00

1.03

.75

.84

.74

.80

.82

.71

.62

.75

.78

.52

.46

.52

.53

.57

.69

.59

.58

.59

.44

.44

.--..-.-.-

Tons per 

day

2,330,000

2,550,000

2, 530, 000

2,900,000

2,370,000

2, 170, 000

2,350,000

2,590,000

2, 090, 000

2, 050, 000

,365,000

,470,000

,370,000

,620,000

,700,000

1, 470, 000

1,230,000

1, 470, 000

1, 520, 000

1,000,000

865,000

968,000

961,000

968,000

1, 110, 000

867,000

776,000

711,000

484,000

446,000

46,300,000

1933

1...-

2

3....

4-...

5....

6....

7....

8....

9....

10...

11 

12...

13...

14...

"15. ..

16...

17...

18...

19-..

20.. T

21...

22...

23...

24...

25...

26...

27...

28...

29...

30...

31-.-

July

34,100

30,900

28,800

26,500

24,060

22,300

20,900

23,200

29,200

30,700

26,400

29,400

24,400

22,000

19,900

19,900

18,300

17,300

15,500

14,500

15,400

13,500

12,100

11, 100

9,920

9,370

10,200

9,810

9,920

8,130

7,600

0.47

.35 1.32

.28

.24

.16

.24

.84

.65

3.08

2.53

1.68

3.47

2.40

1.95

1.78

1.07

.89

1.15

.93

.86

.66

.72

.72

.65

.62

3.12

1.89

1.95

1.51

1.12

Monthly load (tons432,000

292,000

249,000

200,000

155,000

96,200

135,000

526,000

512, 000

2,550,000

1, 800, 000

1,330,000

2,280,000

1, 420, 000

1, 050, 000

955, 000

528,000

415,000

481,000

364,000

357,000

240,000

235,000

216,000

174,000

157,000

858,000

500,000

522,000

331,000

230,000

15, 990, 000

August

7,000

6,470

6,020

7,070

6,630

8,300

7,840

8,090

11,300

11,800

10,500

9,080

7,660

7,170

6,860

6,360

5,960

5,380

4,990

4,820

4,930

4,730

4,970

4,920

4,530

4,040

3,840

3,560

3,410

3,360

3,300

0.48

.47

.44

.47

.41

.45

1.05

.77

2.40

2.11

1.53

1.87

2.54

2.03

1.65

1.16

.80

.86

.75

.66

.54

.66

.99

.91

.98

.95

.81

.87

.72

.50

.43

..... __ ....-_.- ..

90,600

82,000

71,400

89,600

73,300

101, 000

222, 000

168,000

731,000

671,000

433, 000

458,000

525, 000

393,000

305,000

199,000

129,000

125,000

101,000

85,800

71,800

84,200

133,000

121,000

120,000

104,000

83,900

83,500

66,200

45, 300

38, 300

60, 050, 000

September

3,240

3,160

3,080

3,090

3,160

3,090

3,090

3,150

3,200

4,600

6,040

14,600

15,200

9,890

8,580

7,930

7,880

8,050

8,000

7,150

6,700

10,400

13,500

11,200

8,000

7,150

7,420

7,300

6,800

6,400

0.36

.28

.22

.18

.17

.14

.11

.13

.13

.25

.43

4.21

9.06

6.29

4.74

3.97

2.89

2.26

1.55

1.56

1.47

1.75

2.40

3.06

2.81

1.75

.94

.61

1.51

.41

__ ___ . __ ... __

31,400

23,900

18,300

15,000

14,500

11,700

9,170

11,100

11,200

31,000

70,000

1,660,000

3,71'0,000

1,680,000

1,100,000

849,000

614,000

491,000

334,000

301,000

266,000

491,000

874,000

924,000.

606,000

337,000

188,000

120,000

93,500

70,800

14, 960, 000

1 Estimate
38 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 30, 1941 Continued

1933

Day

1-...

2__-

3-..-

4....

5 

6. 

7--~

8..-.

9_--_

10...

11...

12...

13. .

14. .

15. .

16. .

17- .

18. .

19. .

20. .

21. .j

22...

23...

24...

25...

26. ..

27...

28...

29...

30. ..

81...

October

Mean 

discharge 

(secondfeet)

6,000

5,690

5,630

6,930

8,110

8,930

10,600

14 500

12,100

10, 200

9,430

8,750

7,820

8,020

8,060

6,670

6,260

6,990

6,810

5,880

5,460

5, 240 '

5,170

5,080

4,950

4,920

4,920

4,910

4,840

4,700

4,570

Monthly 1

Suspended sediment

Mean 

percent

0.38

.36

.36

.78

1.19

1.57

3.67

5.77

4.76

3.40

2.58

2.43

2.22

2.12

1.53

1.45

1.09

.91

.80

.82

.89

.61

.63

.33

.37

.32

.27

.23

.22

.22

.18

oad (tons)

Tons per 

day

61,600

55,300

53,800

146,000

261,000

379, 000

1,040,000

2,260,000

1,560,000

936, 000

657, 000

574, 000

469,000

459,000

333,000

261, 000

184, 000

172, 000

147, 000

130, 000

131,000

86, 300

87,900

45,300

49,500

42,600

35,900

30,600

28, 700

27,900

22,200

10, 730, 000

November

Mean 

discharge 

(secondfeet)

4,500

4,450

4,520

4,530

4,600

5,140

5,140

5,010

5,080

5,240

5,420

5,470

5,380

5,390

5,400

5,300

5,310

5,440

5,480

5,380

5,350

5,360

5,400

5,430

5,380

5,470

5,420

5,390

5,290

5,330

Suspended sediment

Mean 

percent

10.18

.18 1.17

1.17

.16

.17

1.17

.17

.17

1.18

.18

.21

1 .21

.21

1 .20

1.18

.17

1.16

1.16

1 .16

.15

1.15

.15

1.14

.13

1.18

.15

1.15

.14

1.20

Tons per 

day

21,900

21,600

20,700

20,800

19,900

23, 600

23,600

23. 000

23,300

25, 500

26, 300

31,000

30,500

30,600

29, 200

25, 800

24,400

23,500

23, 700

23,200

21,700

21,700

21, 900

20,500

18,900

26,600

22,000

21,800

20,000

28,800

716, 000

December

Mean 

discharge 

(secondfeet)

7,720

7,300

7,210

6,740

6,230

6,230

6,080

5,920

5,820

5,700

5,500

5,360

5,210

5,070

5,770

5,660

5,290

5,430

5,850

5,830

5,610

5,350

5,010

4,520

4,400

4,180

4,030

4,100

4,350

4,660

5,080

Suspended sediment

Mean 

percent

0.48

.47 1.55

.70 1.60

.47 1.42

.37 1.35

1.30

.27

1.22

.16

1.20

.22

1.21

1.21

.20

1.18

«.16

1.14

.13

1.13

.12

! .ll

.10

1.10

1.10

.07 1.10

.11

Tons per 

day

100, 000

92,600

107,000

127,000

101,000

79,100

68 900

59, 100

55, 000

46,200

40,100

31,800

22,600

27,400

34,300

32,100

30,000

29,300

28,400

25,200

21,200

18,800

17,600

14,600

13,100

11,300

10,900

11,100

8,220

12,600

15,100

1, 292, 000

1934

!--_-

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...

9Q.&y. . _

30 .

31 

January

5,590

5,900

6,440

6,470

6,280

6,320

6,5W

6,500

6,220

6,110

5,940

5,530

5,260

4,820

4,520

4,380

4,270

4,330

4,360

4,440

4,730

4,910

5,030

4,940

4,950

5,130

5,180

5,160

5,130

5,290

5,380

1.15

1.20

.25

1.27

.29

i.2S

1.27

.26

1.25

.23

1.21

1.18

.16

1.14

.12

1.10

.08 1.08

1.09

.09

1.09

.09 1.10

.11

1.10

.10

i.ll

.12

i .12

1.13

.13

Monthly load (tons)

22,600

31, 900

43,500

47,200

49,200

47, 800

47,500

45,600

42,000

37,900

33,700

26,900

22, 700

18, 200

14,600

11,800

9,220

9,360

10,600

10, 800

11,500

11, 900

13,600

14, 700

13, 400

13,900

15,400

16, 700

16,600

18,600

18, 900

748, 300

February

5,270

5,160

5,050

5,050

4,980

4,990

5,130

5,140

5,290

5,380

5,610

6,000

6,150

6,390

6,460

6,370

6,230

5,980

5,740

5,650

5,550

5,460

5,770

6,070

6,420

6,090

6,190

6,190

0.12

.13

.12

.11

.12

.11

.13

» .15

.18

1.18

.17

1.20

1.25

.29

1.32

.33

1.28

.24 1.24

.24

1.22

.21

1.23

.24

1 .26

1 .26

.30

».30

17, 100

18,100

16,400

15,000

16, 100

14,800

18,000

20,800

25,700

26,100

25, 700

32, 400

41,500

50,000

55, 800

56,800

47, 100

38,800

37, 200

36, 600

33,000

31,000

35,800

39,300

45, 100

42, 800

50,100

50,100

937, 200

March

6,360

6,260

e, iea

5,940

5,660

5, 570

5,550

5,430

5,400

5,300

5,260

5,180

5,360

5,420

5,530

5,590

5,520

5,570

5,690

5,780

5,690

5,920

5,980

5,920

5,790

5,690

5,690

5,720

5,590

5,690

5,730

0.28

1.28

.28

1.28

.29

1.2*

.21

1.20

.19

1.20

1.19

.19

1.19

.19 1.20

1.25

.25

i .23

.21

i .22

.23

i .28

.32

1.30

1.28

.24

1.24

.24 1.26

1.26

.33

48,100

47,200

46; 600

44,900

44,300

37,600

31,500

29,300

27,700

28,600

26,900

26,600

27,500

27,800'

29,900

37,700

37,300

34,600

32,300

34, 300

35, 300

44,800

51, 700

48,000

43,800

36,900

36,900

37,100

39,200

39,900

51, 100

1,165,000

i Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 39

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1934

Day

I-...

2 ..

3-...

4- 

5. 

8....

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

Mean 

discharge 

(secondfeet)

5,380

5,250

5,070

5,440

5,730

5,910

5,980

5,920

5,830

5,810

5,850

5,680

5,460

5,240

5,210

5,420

6,680

7,820

8,710

9,650

9,380

9,260

8,850

8,930

9,740

10,600

11.400

11,900

12,500

13,500

Suspended sediment

Mean 

percent

10.25 1.17

1.17

1.18

1.20

.22

.21

1.25

.28

.24

.24

.20

.19

.15

.14

.18

.38

.87

.85

.91

.76

1.65

.57

.64

.69

.83

.82

.95

.86

1.03

Monthly load (tons)..

Tons per 

day

36,300

24,100

23,300

26,400

30,900

35,100

33,900

40,000

44,100

37,600

37,900

30,700

28,000

21,200

19,700

26,300

68,500

184,000

200,000

237,000

192,000

163,000

136,000

154,000

181,000

238,000

252,000

305,000

290,000

375,000

3, 471, 000

May

Mean 

discharge 

(secondfeet)

14,200

14,500

14, 300

13,700

15,000

15,600

14,900

14,000

13,300

13,400

14,900

18,200

21,300

24,100

24,600

24,900

24, 700

22,900

20,600

19,500

19,800

19,600

19,300

18, 700

18,200

17,700

16,800

15,500

16,600

17, 400

17,800

Suspended sediment

Mean 

percent

0.98 -.88

i.80

i.75

.94

.90

.68

.70

.59

.63

.75

1.02

1.29

1.30

1.40

1.36

1.01

.99

.84

.70

.77

.63

.70

.50

.57

.49

.47

.37

.63

1.87

1.39

Tons per

day

376,000

342, 000

309,000

277, 000

381, 000

379,000

274, 000

265,000

212, 000

228,000

302,000

501,000

742,000

846,000

930, 000

914,000

674,000

612,000

467, 000

369, 000

412.000

333,000

365,000

252, 000

280,000

234,000

213,000

155, 000

282,000

879,000

668,000

13, 470, 000

June

Mean 

discharge 

(secondfeet)

18,000

17,000

17,500

18,300

16,700

15,400

14,000

13, 100

12,300

11,600

10,900

10,200

9.460

8,720

7,980

7,470

6,910

6,430

5,960

5,590

5,301

4,940

4,650

4,430

4,260

4.060

3,820

3,510

3,340

3,230

Suspended sediment

Mean 

percent

1.22

1.15

1.29

11.25

i 1.00

.80

.50

.49

.35

.24

.26

.26

.22

.16

.15

1.15

.11

1.08

.07

. .07

.07

.05

.05

.04

.03

.03

.04

.03

.04

.03

Tons per

day

593,000

528,000

610,000

618,000

451,000

333,000

189,000

173,000

116,000

75,200

76,500

71,600

56,200

37,700

32,300

30,300

20,500

13,900

11,300

10,600

10,000

6,670'

6,280

4,780

3,450

3.290

4,130

2,840

3,610

2,620

4, 095, 000

1934

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...

July

3,090

3,040

3,100

3,190

3,180

3,040

2,910

2,800

2,610

2,480

2,370

2,310

2,270

2,170

2,120

2,030

1,980

1,970

1,920

1,840

1,880

1,840

2,070

2,050

1,950

2,040

2,070

2,650

2,150

2,050

2.620

0.04

.04

1.03

1.02

.02

.03

.02

.03

.03

.03

.04

.04

.03

.02

.02

.02

.02

 ,04

.05

.02

.02

.01

.02

.58

2.02

1.76

.80

.55

.94

.51

1.68

Monthly load (tons)..

3,340

3,280

2,510

1,720

1,720

2,460

1.570

2,270

2,110

2,010

2,560

2,490

1,840

1,170

1,140

1,100

1,070

2,130

2,590

994

1,020

497

1,120

32,100

106,000

96,900

44,700

39,400

54,600

28,200

119, 000

563,600

August

2,810

2,440

2,120

1,980

1.970

2,030

1,890

1,750

1,590

1,620

1,490

1,750

1,750

1,780

2,030

2,010

2,000

2,000

2,130

3,300

2,860

3,010

2,880

2,600

2,590

2,650

2,640

3,410

6,110

5,930

8,560

__ . _ ....

1.68

.90

1.70

1 1.00

1.64

1,26

.93

.65

.44

.26

.33

.48

.37

.51

2.25

1.71

.92

2.33

2.26

,1.48

1.34

1.76

1.39

2.42

1.78

1.20

1.20

1.31

9.10

4.84

11.5

.. __ __

127, 000

59,300

40,100

53,500

87,200

69,100

47,500

30.700

18,900

11,400

13,300

22,700

17,500

24,500

123,000

92,800

49, 700.

126, 000 v

130,000

132,000

103,000

143,000

108,000

170,000

124,000

85,900

85,500

121,000

1,500,000

775, 000

2, 660, 000

7, 152, 000

September

7,980

5,250

4,430

3,300

2,650

2,600

2,740

2,540

2,440

2,130

2,190

2,210

2,160

2,030

1,950

1,850

1,950

2,310

2,430

2,540

2,570

2,340

2,170

1,960

1,860

1,810

1,770

4,210

4,050

3,500

6.52

6.36

6.28

5.07

14.00

2.97

2.33

2.14

1.81

1.28

1.25

1.80

.60

.54

.79

.62

.64

.68

.48

.62

.97

.78

.61

.35

.26

.30

.34

.65

1.40

4.07

1,400,000

902,000

751,000

452,000

286,000

208,000

172,000

147,000

119,000

73,600

73.900

47,700

35,000

29,600

41,600

31,000

33,700

42,400

31,500

42,500

67,300

49,300

35,700

18,500

13,100

14,700

16,200

73,900

153,000

385,000

5, 746, 000

Estimated.
40 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1934

Day

!.--_

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...

October

Mean 

discharge 

(secondfeet)

3,080

3,070

3,500

3,460

3,220

3,060

2,930

2,910

2,990

2,930

2,830

2,740

2,670

2,610

2,580

2,590

2,460

2,430

2,530

2,520

2,490

2,590

2,690

2,670

2,690

2,690

2,680

2,680

2,750

2,840

2,810

Suspended sediment

Mean 

percent

3.20

2.24

»1.50

.94

.62

.42

.37

.30

.25

.25

.22

.16

.18

.17

.17

.16

.14

.14

.14

.13

.12

.11

.10

.15

.12

.12

.12

.12

.13

.12

.14

Monthlyload (tons) .

Tons per

day

266,000

185, 000

142,000

87, 800

53,900

34,700

29,300

23,600

20,200

19,800

16, 800

11, 800

13,000

12,000

11,900

11,200

9,290

9.180

9,560

8,860

8,070

7,700

7,260

10,800

8,720

8,720

8,690

8,690

9,670

9,210

10.600

1,074,000

November

Mean 

discharge 

(secondfeet)

2,810

2,820

2,760

2,720

2,720

2,760

2,800

2,740

2,720

2,810

2,910

3,000

2,990

3,030

3,170

3,330

3,470

3,460

3,440

3,470

3,560

3,830

3,780

3,850

3,830

3,990

3.930

4,000

4,030

3,990

.. ___ ...

Suspended sediment

Mean 

percent

0.13

.13

.13. i.l2

.12

.12

.10

.12

.12

.12

.11

.14

.14

.16

.15

.16

.18

.18

.16

.15

.18

.19

.24

.22

.25

.24

.21

.21

.20

.20

._ __ ....

Tons per 

day

9,860

9,t»0

9,630

8,800

8,800

8,940

7,560

8,880

8,800

9,100

8,640

11,300

11,300

13, 100

12,900

14,400

16,900

16,800

14,800

14,000

17,300

19,700

24,500

22,900

25,900

25,900

22,300

22, 700

21,800

21,500

449,000

December

Mean 

discharge 

(secondfeet)

3,920

3.870

4,000

4,040

3,970

3,800

3,740

3,570

3,300

3,080

2,950

2,830

2,880

3,120

3,500

3,860

3,980

4,420

4,630

4,480

4,460

4,660

4,780

4,540

4,340

4,160

4,200

4,280

4,410

4,470

4,400

Suspended sediment

Mean 

percent

0.17

.18

.18

.20 J.18

.15

.12

.11

.14

.10

.11

.09

.09

.09

.11

.16

.16

.36

.30

.30

.29

.28

.29

.24

.21

.18

.18

.18

.20

.19

.18

_ _ _ .

Toasper 

4ay

18,000

18,800

18,400

21,800

19,300

15,400

12, 100

10,600

12,500

8.320

8,750

6,890

6,990

7,590

10,400

16.700

17,200

43,000

37,500

36,300

34,900

35,200

37,400

29,400

24,600

20,200

20,400

20,800

23,800

22,900

21,400

638,500

1935

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...

January

4,400

4,420

4,360

14,410

4,340

4,210

4,200

3,990

4,210

4,480

4,160

5,220

5,650

7,980

6,380

5,690

5,950

6,350

5,970

5,800

5,130

4,970

4,580

4,050

3,360

2,940

3,000

3,040

3,300

3,910

4,820

0.14

.22

.17

.18

.19

.18

.18

.76

.28

1.90

1,13

1.10

1.19

3,47

2.35

1.02

.98

1.05

.72

.81

.67

.48

.32

.22

.16

.10

.12

.22

.19

.21

.32

Monthlyload (tons) _

16,600

26,200

20,000

21,400

22,300

20,500

20,400

81,900

31,800

229,000

127,000

155,000

182,000

748, 000

405,000

157,000

157,000

180,000

116,000

127,000

92,800

64,400

39.600

24,100

14,500

7,940

9.720

18,100

16,900

22,200

41,600

3, 196, 000

February

5,300

5,320

5,310

5,330

5,560

5,560

5,560

. 5, 370

5,240

5.650

6,300

6,000

5,880

6,340

6,020

5,580

5,560

5,520

5,580

5,400

5,270

4,970

4,710

4,580

4,800

5,570

6,100

5,990

0.38

.34

.31

1.35

1.35

.40

.44

.40

.38

.36

1.03

.90

.71

.75

.92

.62

.47

.40

.51

.36

.32

.29

.28

.24

.22

.61

.59

.57

54,400

48,800

44,400

50,400

52,500

60,100

66,000

58,000

53, 800

54,900

175,000

146,000

113, 000

128,000

150,000

93,400

70,600

59, 600

76,800

52,500

45,500

38,900

35,600

29,700

28,500

91,800

97,200

92,200

2, 068, 000

March

5,680

5,540

5,460

5,230

5,040

4,780

5,060

5,770

5,920

5,890

5,890-

5,620

5,530

5,480

5,360

5,090

5,090

7,420

8,080

7,380

6,920

6,790

6,730

6,590

6,730

6,940

6,940

6,650

6,700

6,940

7,440

0.46

,44

.48

1.35

.30

.28

.32

.44

.46

.54

.44

.41

.35

.38

.36

.43

.44

1.72

1.55

1.16

.94

.89

.79

.70

.61

.60

.64

.61

.56

.59

.72

70,600

65,800

70,800

49,400

40,800

36,100

43,700

68.600

73,500

85,900

70,000

62,200

52,300

56,200

52, 100

59,100

60,500

345,000

338,000

231,000

176,000

163, 000

144,000

125,000

111,000

112,000

120,000

110,000

101,000

111,000

145,000

3,350,000

i Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 41

TABLE 9. Mean daMy discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1935

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

Mean 

discharge 

(secondfeet)

7,970

8,260

8,890

9,480

9,330

9,630

10,900

11,600

11,600

12,300

15,600

14,400

13,200

11,300

10,800

10,200

10,000

10,900

12,300

13,500

14,100

14,700

14,400

13,900

13,600

14,000

15,800

16,900

15,200

14,000

Moutbly lo£

Suspended sediment

Mean 

percent

0.93

1.06

1.26

1.24

1.31

1.38

1.40

1.48

1.42

1.60

3.16

2.16

1.58

1.31

1.12

.89

' * .81

.84

1.11

1.46

1.38

1.38

1.23

1.20

1.10

1.06

1.26

1.40

1.08

.92

A (tons)..

Tons per

day

200,000

236,000

302,000

317,000

330,000

355, 000

412, 000

464,000

445,000

531,000

1, 330, 000

840,000

563,000

400,000

327,000

245,000

219,000

247,000

369,000

532,000

525, 000

548,000

478, 000

450, 000

404,000

401,000

538,000

639,000

443,000

348,000

13, 440, 000

May

Mean 

discharge 

(secondfeet)

13,700

14,300

15,600

16,700

17,400

16,400

15,300

14,100

13,600

13,400

13,100

13,300

14,300

16,200

18,500

20,900

24,100

24,000

23, 300

24,000

25,200

26,300

29,700

31,000

26,800

26,000

27,300

31,100

36,200

40,000

44,500

Suspended sediment

Mean 

percent

0.85

.90

1.04

1.22

1.28

1.04

.99

1.06

.88

.73

.68

.68

.77

.80

.97

1.13-

1.45

1.52

1.36

1.32

1.26

1.22

1.38

1.48

1.48

1.08

1.01

1..01

1.26

1.38

1.54

Tons per 

day

314, 000

348, 000

438, 000

550,000

601, 000

461,000

409,000

404,000

323,000

264,000

241,000

244,000

297, 000

350,000

490,000

638,000

944,000

985,000

856,000

855,000

857,000

866,000

1, 110, 000

1, 240, 000

1, 070, 000

758,000

744,000

848,000

1, 230, 000

1, 490, 000

1, 850, 000

22, 080, 000

June

Mean 

discharge 

(secondfeet)

48,100

48,600

49,400

48, 700

46,200

45,400

47,100

50,700

54,200

57,800

63,600

69,800

72,600

84,300

86,400

87,200

91,900

101, 400

103, 100

89,000

80,900

77,000

73,800

73,400

70,300

65,400

63,500

58,800

53,700

50,300

Suspended sediment

Mean 

percent

1.70

1.90

1.58

1.45

1.31

1.12

1.08

1.10

1.28

1.28

1.25

1.26

1.14

1.22

1.06

1.09

1.03

1.01

.82

.79

.72

.55

.54

.58

.56

.44

.48

.44

.37

.36

Tons per 

day

2, 210, 000

2,490,000

2, 110, 000

1,910,000

1, 630, 000

1, 370, 000

1,370,000

1,510,000

1, 870, 000

2,000,000

2,150,000

2, 370, 000

2,230,000

2, 780, 000

2,470,000

2, 570, 000

2, 560, 000

2, 770, 000

2,280,000

1,900,000

1, 570, 000

1,140,000

1,080,000

1, 150, 000

1,060,000

777,000

823,000

699,000

537,000

489,000

51, 880, 000

1935

l-.~

2--..

3...-

4 ...

5-__.

6....

7-...

8-.-.

9

10.--

11-..

1.2. . .

13.. _

14...

15- _.

16-..

17-.-

18-.-

19-.-

20...

21.--

22,.-

23...

24-.-

25...

26...

27.--

28.-_

29...

30...

31...

July

47,600

43,800

41,200

39,200

36,800

35; 000

33,400

31,800

29,700

27,700

26,500

25,300

24,300

23,800

23,200

22,400

21,900

20,900

19,500

18,900

20,800

17,200

18,000

17,100

16,000

15,700

14,800

14,100

13,000

12,100

11.400

0.36

.35

.33

.28

.28

.30

.22

.23

.23

.20

.17

.19

.16

.16

.16

.15

.13

.13

.14

.30

.39

.62

.60

.35

.24

.27

.54

.46

.23

.22

.19

Monthly load (tons)..

463,000

414, 000

367,000

296, 000

278,000

284,000

198,000

197,000

184,000

150,000

122,000

130,000

105, 000

103,000

100,000

90,800

76,900

73,400

73,700

153,000

219, 000

288,000

292,000

162, 000

104,000

114,000

216,000

175, 000

80,700

71,900

58,500

5, 640, 000

August

10,800

11,000

10,600

10,000

10,500

12, 700

11,100

10,700

10,300

9,950

10,200

10,200

9,330

8,720

8,880

9,040

9,680

8,120

8,400

7,560

8,040

8,140

7,600

7,660

7,380

9,640

8,470

10,600

9,950

8,980

8,240

0.16

.25

.17

.23

.36

1.82

1.54

.72

.44

.46

1.72

1.13

.97

1.11

1.16

.98

.76

1.35

.53

.40

.44

.54

.48

.50

.52

4.81

2.56

2.74

1.86

1.69

2.14

46,700

74,300

48,700

62,100

102,000

624,000

462,000

208,000

122, 000

124,000

474,000

311, 000

244,000

261, 000

278, 000

239,000

199,000

296,000

120,000

81,700

95,500

119,000

98, 500

103, 000

104,000

1, 250, 000

585,900

784,000

500,000

410, 000

467,000

8, 902, 000

September

9,140

10,500

11,700

12,300

10,100

8,630

7,670

6,880

6,450

6,250

6,270

5,820

5,950

6,490

6,410

6,870

7,190

6,370

5,740

5,450

5,480

5,100

4,740

4,500

4,360

4,440

7,420

13,000

9,630

18,100

1.43

1.83

2.80

5.02

2.54

1.94

2.00

1.64

1.12

.97

.72

.64

.56

.65

.54

.56

.40

.33

.41

.31

.21

.16

.15

.14

.12

.15

.24

.90

2.14

4.14

353, 000

519,000

885,000

1, 670, 000

693,000

452,000

414,000

305,000

195,000

164,000

122,000

101,000

90,000

114,000

93,500

104,000

77,700

56,800

63,500

45,600

31,100

22,000

19,200

17,000

14,100

18,000

48,100

316,000

556,000

2,020,000

9, 580, 000
42 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of sus>- 

pended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1935

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...

October

Mean 

discharge 

(secondfeet)

15,800

10,500

9,250

8,800

8,020

7,490

7,240

6,830

6,550

6,300

6,020

5,820

5,600

5,380

5,140

5,010

4,950

4,820

4,660

4,670

4,650

4,730

4,570

5,440

5,560

5,430

5,100

4,960

5,050

5,000

5,040

Monthly lo

Suspended sediment

Mean 

percent

5.09

4,65

3.44

1.98

1.28

.88

.69

.54

.45

.42

.31

.26

.22

.19

.16

.14

.13

.12

.11

.11

.12

.12

.11

.12

.14

.15

.16

.20

.49

.44

.26

ad'(tons)..

Tons per 

day

2, 170, 000

1, 320, 000

859, 000

470, 000

277,000

178, 000

135,000

99,600

79,600

71,400

50,400

40,900

33,300

27,600

22,200

18,900

17,400

15,600

13,800

13,900

15, 100

15,300

13, 600

17, 600

21, 000

22,000

22,000

26, 800

66,800

59, 400

35,400

6, 229, 000

November

Mean 

discharge 

(secondfeet)

5,190

5,230

5,080

5,250

5,260

5,260

5, 360

5,570

5,680

5,680

5,710

5,650

5,560

5,790

5,960

6,020

5,970

5,830

5,690

5,610

5,540

5,610

5,790

5,760

5,920

5,930

5,900

5,920

5,710

5,650

Suspended sediment

Mean 

percent

0.23

.20

.15

.15

.13

.13

.12

.13

.13

.12

.13

.13

.12

.12

.12

.11

.11

.10

.10

.09

.10

.09

.09

.11

.11

.11

.10

.12

.11

.15

Tons per 

day

32,200

28,200

20,600

21,300

18,500

18,500

17,400

19,600

19, 900

18,400

20,000

19,800

18,000

18,800

19,300

17,900

17, 700

15, 700

15,400

13, 600

15,000

13,600

14, 100

17,100

17,600

17, 600

15,900

19,200

17, 000

22, 900

560, 800

December

Mean 

discharge 

(secondfeet)

57750"

5,790

5,820

5,820

5,760

6,870

6,230

5,480

5,040

4,970

4,970

4,910

4,960

5,010

5,060

4, 970

4,790

4,600

4,620

4,670

4,600

4,230

3,630

3,350

3,280

3,140

3,170

3,330

3,560

3,760

4,000

Suspended sediment

Meaja 

percent

0.14

.11

.10

.10

.09

.11

.22

.19

.13

.11

.08

.08

.09

.10

.09

.09

.09

.09

.09

.08

.08

.07

.07

.06

.05

.06

.06

.06

.07

.08

.06

Tons per 

day

21/700

17,200

15,700

15,700

14,000

20,400

37,000

28,100

17, 700

14,800

10, 700

10,600

12,100

13,500

12,300

12,100

11, 600

11,200

11,200

10,100

9,940

7,990

6,860

5,430

4,430

5,090

5,140

5,390

6,730

8,120

6,480

389, 300

1936

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__-

January

3,750

3,820

4,100

4,310

4,180

4,220

4,280

4,220

4,180

3,900

4,310

4,580

4,520

4,410

4,400

4,610

4,730

5,040

5,250

5,260

5,100

5,040

4,870

4,780

4,560

4,450

4,390

4,410

4,670

4,930

5,210

0.08

.08

.06

.06

.07

.07

.07

.07

.06

.06

.05

.06

.07

.07

.06

.06

.06

.06

.06

.06

.08

.07 '

.06

.05

.07

.06

.06

.04

.06

.06

.07

Monthlyload (tons')

8,100

8,250

6,640

6,980

7,900

. 7, 980

8,090

7,980

6,770

6,320

5,820

7,420

8,540

8,330

7,130

7,470

7,660

8,160

8,500

8,520

11,000

9,530

7,890

6,450

8,620

7,210

7,110

4, 760

7,570

7,990

9,850

240, 500

February

5,390

5,560

5,440

5,650

5,580

5,610

5,160

4,910

5,190

5,350

5,050

4,650

4,540

4,910

4,970

5,190

5,450

6,160

6,510

6,530

6,390

6,480

6,560

6,300

6,630

6,730

6,070

6,510

7,780

0.08

.15

.16

.16

.17

.27

.17

.17

.17

.14

.09

.10

.08

.07

.07

.14

.10

.13

.16

.16

.16

.16

.18

.19

.19

.32

.18

.28

.35

11, 600

22,500

23, 500

24, 400

25,600

40, 900

23,700

22,500

23, 800

20, 200

12, 300

12, 600

9,810

9,280

9,390"

19, 600

14, 700

21, 600

28, 100

28,200

27, 600

28,000

31,900

32, 300

34,000

58,100

29,500

49,200

73,500

.____- -.____,

768,400

March

7,370

6,740

6,340

5,970

6,020

7,340

8,770

9,010

8,790

8,500

8,270

8,480

8,740

9,140

8,980

8,750

9,010

> 9, 250

9,330

9,270

8,800

8,630

8,420

8,470

8,470

8,430

8,500

7,850

7,490

7,660

7,220

0.47

.38

.36

.30

.24

.25

.42

.66

1.17

1.28

1,10

1.03

.86

.77

.81

.74

.65

.62

.64

.51

.49

.45

.39

.37

.34

.35

.37

.37

.40

.34

.37

93,500

69,200

61, 600

48,400

39,000

49,500

99,500

161, 000

278, 000

294,000

246,000

236, 000

203, 000

190, 000

196,000

175, 000

158,000

155, 000

161,000

128,000

116, 000

105, 000

88,700

84,600

77, 800.

79,700

84.900

78, 400

80, 900

70,300

72,100

3,980.000
QUANTITIES OF SUSPENDED SEDIMENT 43

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept, 80, 1941 Continued

1936

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...

2,5...

26...

27--.

28-.-

29..-

30...

31

April

Mean 

discharge 

(secondfeet)

6,740

7,000

7,670

7,840

7,920

7,310

7,640

7,820

7,180

6,810

6,720

7,340

9,810

10,200

11,500

14,300

17,600

21, BOO

23, 700

27,600

32, 700

35,400

36,800

39,400

43,100

47,700

49,600

49,900

51, 100

51,700

Suspended sediment

Mean 

percent

0.35

.27

.30

.44

.39

.39

.38

.38

.39

.28

.26

.22

.71

.89

1.09

1.18

1.46

1.68

1.64

1. 62

1.65

1.57

1.57

1.32

1.43

1.58

1.39

1.59

1.32

1.26

Monthly load (tons)

Tons per

day

63,700

51,000

62.100

93, 100

83,400

77,000

78,400

80,200

75,600

51,500

47, 200

43,600

188,000

245,000

338, 000

456,000

694,000

980,000

1, 050, 000

1, 210, 000

1, 460, 000

1, 500, 000

1, 560, 000

1, 400, 000

1, 660, 000

2, 030, 000

1,860,000

2, 140, 000

1, 820, 000

1,760,000

23, 160, 000

May

Mean 

discharge 

(secondfeet)

51,200

51, 100

49,900

47.100

44,400

45,900

50,700

58.70Q

66,400

64,400

58,600

52, 700

46,200

42,300

40,500

44,000

49,100

55,200

62,600

67,700

71,800

70, 600

74,600

75,100

70,600

67,900

66,100

65,600

65,600

65, 400

64,600

Suspended sediment

Mean 

percent

1.16

1.01

. .95

.80

.79

.67

.74

.94

1.06

.90

.74

.61

.54

.51

.42

.44

.51

.55

.53

.64

.59

.59

.58

.58

.44

.51

.54

.47

.45

.50

.46

Tons per 

day

1,600,000

1, 390, 000

1,280,000

1, 020, 000

947,000

830,000

1, 010, 000

1, 490, 000

1,900,000

1, 560, 000

1, 170, 000

868,000

674, 000

582, 000

459, 000

523,000

676, 000

820,000

896,000

1, 170, 000

1, 140, 000

1, 120, 000

1, 170, 000

1, 180, 000

839,000

935, 000

964, 000

832,000

797, 000

883,- 000

802,000

31, 530, 000

June

Mean 

discharge 

(secondfeet)

63,100

64,900

68,200

69,400

66,400

60,300

54,400

50,000

46,800

44,300

44,200

47,200

48, 300

47,900

47,100

45, 900

44,800

43,600

42,000

40,900

39,400

38.100

36,800

34,800

32,800

31,300

30,100

28,700

27,100

26,300

Suspended sediment

Mean 

percent

0.46

.54

.48

.57

.45

.50

.46

.40

.39

.33

.40

.38

.35

.34

.32

.33

.34

.34

.27

.30

.25

.27

.28

.28

.22

.21

.19

.20

.23

.20

Tons per 

day',

784,000

946,000

884,000

1, 070, 000

807,000

814,000

676,000

540,000

493,000

395,000

477,000

484,000

456,000

440,000

407,000

409,000

411,000

400,000

306, 900

331,000

266,000

278,000

278, 000

263,000

195,000

177,000

154,000

155,000

168,000

142,000

13, 610, 000

1936

!.. 

2-...

3.-..

4---.

5.. 

6..-

7---

8- 

9_---

10-..

11...

12.--

13..-

14...

15.._

16-.-

17..-

18--.

19--.

20.--

21-..

22.-.

23_-_

24_._

25-._

2S7-""

28---

29--.

30-..

31

July

25,600

24,100

23, 100

22,400

21,200

19, 300

17,900

16,600

15, 700

14,400

15,500

15, 900

29,800

29,200

20,500

17, 800

16,900

16,300

14,700.

13,700

14,300

15, 200

14, 300

14,100

12,900

12,100

11,800

10,800

11,400

10,600

8,810

0.18

.17

.17

.16

.15

.17

.18

.12

.13

.13

.12

2.22

.82

4.72

1.72

3.13

3.62

2.40

1.84

1.02

.89

.91

.76

.62

.74

.56

.66

1.11

1.24

1.31

.99

Monthly load (tons)

124, 000

111,000

106,000

96, 800

85, 900

88,600

87, 000

53,800

55,100

50,500

50,200

953, 000

660, 000

3, 720, 000

952, 000

1, 500, 000

1, 650, 000

1, 060, 000

730,000

377, 000

344, 000

373, 000

293, 000

236, 000

258, 000

183,000

210, 000

324, 000

382,000

375, 000

235, 000

15. 720, 000

August

9,800

9,390

9.450

11,200

15,300

19, 700

29, 700

24, 700

27,200

27, 200

23,200

21,000

18,600

16,900

15, 200

13,300

12, 800

12, 800

12,200

12, 400

11,900

11, 100

13,300

14,900

12, 300

11,000

10,500

9,720

9,010

9,300

10,800

1.13

.94

.92

1.48

3.14

4.22

5.35

6.54

5.31

3.99

3.18

2.73

2.53

2.12

2.22

1.68

1.49

1.15

1.42

1.22

i 1.40

i 1.60

1.75

2.13

2.08

2.19

2.07

1.34

.93

1.15

5.50

299,000

238,000

235.000

448,000

1, 300, 000

2,240,000

4, 290, 000

4, 360, 000

3, 900, 000

2, 930, 000

1,990,000

1, 550, 000

1, 270, 000

967, 000

911, 000

603, 000

515, 000

397, 000

468,000

408,000

450, 000

480,000

628,000

857,000

691,000

650,000

587, 000

352,000

238,000

289,000

1, 600, 000

36, 140, 000

September

13,800

22,400

21,500

18,300

16,400

14,900

13,900

12,600

10.800

10.200

9,440

8,830

9,520

9,750

8,980

8,600

8,080

7,900

7,870

7,590

7,410

9,490

8,220

8,080

8,100

7,870

6,880

6,350

5,660

5,280

3.03

4.47

7.74

6.86

4.41

3.43

3.10

2.54

2.40

1.79

1.30

1.38

1.57

2.62

1.87

1.49

1.32

1.00

.80

.69

.53

3.29

2.08

3.02

1.98

1.35

1.74

1.18

1.08

.91

1, 130, 000

2, 700, 000

4, 490, 000

3, 390, 000

1, 950, 000

1, 380, 000

1,160,000

864,000

700,000

493,000

331,000

329,000

404,000

690,000

453, 000

346, 000

288,000

210,000

170,000

141,000

106,000

843,000

462, 000

659,000

433,000

287,000

323,000

202,000

165, 000

130,000

25, 230, 000

1 Estimated.

72560R 47-
44 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 30, 1941 Continued

1936

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...

ft

October

Mean 

discharge

(secondfeet)

5,180

5,300

5,120

5,150

5,240

- 5,240

5,390

5,580

5,540

5,520

5,700

5,780

5,740

5,680

5,690

5,660

5,650

 5.560

5,430

5,380

5,870

5,790

5,900

6,520

7,050

7,410

7,120

6,980

6,960

6,820

6,830

Suspended sediment

Mean

percent

0.64

.50

.42

.40

.37

.41

.36

.31

.32

.26

.22

.24

.24

.22

.21

.23

.21

.19

.18

.18

.24

.70

.35

.55

.46

.55

.59

.49

.48

.54

.40

ionthlyload (tons)..

Tons per

day

89, 500

71,600

58, 100

55,600

52,300

58,000

52, 400

46, 700

47,900

38,800

33, 900

37,500

37,200

33,700

32, 300

35,100

32,000

28,500

26,400

26,100

38, 000

109, 000

55,800

96,800

87, 600

110, 000

113, 000

92,300

90,200

99,400

73,800

1, 860, 000

November

Mean 

discharge

(secondfeet)

7,250

10, 700

9,560

9, 670

9,100

9,130

8,710

8,310

7,940

7,570

7,260

7,310

7,480

7,510

7,290

 7,220

7,120

7,050

7,090

7,160

7,070

7,100

7,200

7,180

7,200

7,170

7,040

6,990

6,960

6,830

Suspended sediment

Mean

pe?cent

0.45

1.78

. 1.70

1.91

1.58

.96

.95

,90

.84

.69

.44

.40

.47

.36

.34

.36

.33

.20

.20

.30

.19

.16

.28

.20

.21

.16

.26

.16

.17

.22

Tons per

day

88,100

514, 000

439,000

499, 000

388, 000

237, 000

223, 000

202, 000

180, 000

141, 000

86,200

78,900

94,900

73,000

66,900

70,200

63, 400

38, 100

38,300

58,000

36,300

30, 700

54, 400

38,800

40,800

31,000

49,400

30,200

31,900

40,600

3, 963, 000

December

Mean 

discharge

(secendfeet)

6,600

6,480

6,270

6,200

5,960

5,800

5,740

5,560

5,420

5,230

5,110

4,880

4,620

4,370

4,210

4,130

4,110

4,220

4,580

5,160

5,390

5,700

5,820

5,860

6,030

6,020

5,820

5,900

6,410

6,830

6,070

Suspended sediment

Mean

percent

0.13

.15

.14

.13

.16

.12

.40

.11

.10

.10

.09

.11

.10

.10

.08

.07

.07

.06

.08

.08

.12

.08

.11

.11

.11

.12

.10

.19

.11

.24

.16

Tons per

day

23,200

26,200

23,700

21,800

25,700

18,800

15,500

16,500

14,600

14, 100

12,400

14,500

12, 500

11,800

9,090

7,810

7,770

6,840

9,890

11,100

17,500

12,300

17,300

17,400

17, 900

19, 500

15,700

30,300

19,000

44,300

26,200

541, 200

1937

!_.__

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...

January

5,970

6,010

5,760

5,270

4,960

4,430

3,810

3,560

3,460

2,960

2,860

2,750

2,020

2,200

3,270

3,010

2,520

2,810

3,450

3,840

3,840

3,810

3,590

2,980

2,820

2,560

2,520

2,880

3,050

3,150

3, 580

Monthly loi

0.12

.12

.10

.10

.12

1.10

.07

.07

.06

.07

.06

.05

.04

.04

.07

.05

.05

.05

.04

.05

.04

.04

.03

.04

.04

.04

.03

.03

.03

.03

.04

d (tons).-

19, 300

19, 500

15,600

14,200

16, 100

12, 000

7,200

6,730

5,610

5,590

4,630

3,710

2,180

2,380

6,180

4,060

3,400

3,790

3,730

5,180

4,150

4,110

2,910

3,220

3,050

2,760

2,040

2,330

2,470

2,550

3,870

194, 500

February

4,130

4,590

4,740

4,800

4,950

5,110

5,820

8,910

10,000

17, 100

12, 100

9,670

8,720

9,090

9,140

8,930

18, 200

17, 000

16,800

13,400

12,000

11,500

9,890

8,820

8,240

7,930

7,890

8,280

0.05

.06

.05

.05

.07

.08

.13

.34

.46

4.32

1.36

1.28

.95

.60

.55

.44

2.34

2.76

2.29

1.88

1.56

1.34

1.03

.77

.68

.53

.45

.70

5,580

7,440

6,400

6,480

9,360

11,000

20,400

81,800

124, 000

1, 990, 000

440,000

334, 000

224, 000

147,000

136, 000

106,000

1,150,000

1, 270, 000

1, 040, 000

680,000

505, 000

416, 000

275, 000

183, 000

151,000

113,000

95, 900

156, 000

9, 688, 000

March

8,550

8,270

8,200

8,090

8,030

8,000

8,310

8,320

8,340

8,640

9,190

10,200

10,800

11,900

12,900

14,600

17,700

16,100

19,600

22,000

22,300

19,700

20,100

18, 000

17,300

18, 000

16, 300

14,900

14, 000

13, 100

12, 700

0.54

.51

.50

.43

.41

.42

.49

.46

.54

.57

.65

.78

.95

1.01

1.32

1.75

2.79

2.32

2187

2.87

2.76

2.37

2.26

1.97

1.91

1.74

1.53

1.39

1.26

.99

.89

125, 000

114,000

111, 000

93,900

88,900

90, 700

110, 000

103, 000

122, 000

133, 000

161, 000

215, 000

277, 000

325, 000

460, 000

690, 000

1,330,000

1, 010, 000

1, 520, 000

1, 700, 000

1, 660, 000

1, 260, 000

1, 230, 000

957, 000

892, 000

846, 000

673,000

559,000

476, 000

350,000

305, 000

17, 990, 000

1 Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 45

TABLE 9. Mean "daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 30, 1941 Continued

1937

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

Mean 

discharge 

(secondfeet)

12,200

11,600

10,800

11,200

13,800

15,300

13,900

13,100

13,900

15,000

15,000

17,300

19,200

20,400

22,700

24,900

28,800

34,200

43,700

44,600

42, 100

43,700

42,700

40,500

42,500

41,800

36,500

32,000

31,300

34,500

Suspended sediment

Mean 

percent

0.70

.70

.62

.68

1.16

1.45

1.23

1.10

1.00

1.18

1.02

1.37

1.80

1.75

2.04

2.03

2.32

2.24

2.95

2.78

2.48

2.19

2.25

2.37

2.07

2.06

1.65

1.40

1.37

1.43

Monthly load (tons).

Tons per 

day

231,000

219,000

181,000

206,000

432,000

599,000

462,000

389,000

375,000

478, 000

413,000

640,000

933,000

964,000

1, 250, 000

1,360,000

1, 800, 000

2, 070, OuO

3, 480, 000

3, 350, 000

2,820,000

2, 580, 000

2, 590, 000

2, 590, 000

2,380,000

2, 320, 000

1, 630, 000

1, 210, 000

1, 160, 000

1, 330, 000

40,440,000

May

Mean 

discharge 

(secondfeet)

36,000

32,700

28,500

25,600

25, 800

30,200

35,700

41,400

43,600

43,200

50,400

57,200

65,400

71,400

67,900

69,400

72, 100

78,500

82, 100

81,500

83,600

77,000

72,500

70,800

69,100

66,600

63,100

58,400

53,600

48,500

48,100

Suspended sediment

Mean 

percent

1.46

1.00

.88

.76

.78

.92

1.00

1.28

1.28

1.26

1.40

1.56

1.92

1.64

1.40

1.38

1.43

1.24

1.19

1.04

1.12

1.00

.98

.90

.88

.82

.86

.70

.62

.66

.66

Tons per 

day

1,420,000

883,000

677,000

525,000

543,000

750,000

964,000

1, 430, 000

1,510,000

1, 470, 000

1, 910, 000

2, 410, 000

3,390,000

3, 160, 000

2, 570, 000

2, 590, 000

2, 780, 000

2, 630, 000

2, 640, 000

2, 290, 000

2,530,000

2, 080, 000

1,920,000

1, 720, 000

1,640,000

1,470,000

1,470,000

1,100,000

897,000

864,000

857, 000

53, 090, 000

June

Mean 

discharge 

(secondfeet)

51,600

60,300

64,900

60,100

55,900

55,500

54,700

51,300

47,200

43,300

39,100

36,300

34,800

33,100

' 33,000

33,800

34,900

32,900

31,600

30,400

31,400

34,000

34,100

33,600

33,500

34,200

32,600

32,400

29,300

31, 100

 -.

Suspended sediment

Mean, 

percent

0.71

.88

.78

.85

.75

.60

.60

.56

.56

.56

.48

.43

.44

.40

.41

.36

.46

.44

.34

.31

.45

.36

.41

.34

.40

.38

.62

.44

.38

.40

 

Tons per 

day

987,000

1, 430, 000

1, 370, 000

1,380,000

1, 130, 000

899,000

886,000

776,000

714,000

655,000

607,000

421,000

413,000

357,000

365,000

329,000

433,000

391,000

290,000

254,000

382,000

330,000

377,000

308,000

362,000

351,000

546,000

385,000

301,000

336,000

17, 660, 000

1937

1--.V.

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...

July

30,800

28,800

27,400

25,600

24,700

22,500

20,900

19,500

18,700

18,800

19,100

21,600

27,100

27,200

30,200

31,200

30,900

32,000

31,300

28,200

25,000

21,900

19,200

16,900

14,900

13,600

12,400

11,300

11,200

11,800

14,500

0.40

1.00

.51

.36

.21

.25

.28

.33

.38

1.15

1.23

.67

2.47

2.52

2.55

. 2.87

2.73

3.26

2.56

2.40

2.20

1.91

1.64

1.36

1.24

1.14

.98

.71

.52

.40

1.32

Monthly load (tons).

333,000

778, 000

377,000

249,000

140,000

152,000

158,000

174,000

192,000

* 584,000

634,000

391,000

1, 810, 000

1,850,000

2,080,000

2,420,000

2,280,000

2,820,000

2, 160, 000

1,'830,000

1,480,000

1,130,000

850, 000

621, 000

499, 000

419,000

328,000

217,000

157, 000

127,000

517, 000

27,760,000

August

13,300

12,100

11,100

10,300

10, 100

10,300

9,420

9, 340

8,400

7,620

7,300

7,300

7,340

7,040

6,350

5,820

5,460

5,180

4,950

4,870

4,510

4,220

4,110

5,180

4,830

4,510

4,490

4,450

4,310

4,690

4,290

1.61

1.92

2.14

2.08

1.60

.79

.69

.72

.62

.94

.78

.67

.93

1.16

.79

.54

.48

.30

.23

.28

.22

.19

.24

.26

1.24

.32

.34

.34

.26

.19

.52

578,000

627,000

641,000

578, 000

436,000

220,000

175,000

182, 000

141,000

193,000.

154,000

132,000

184,000

220,000

135, 000

84,900

70,800

42,000

30,700

' 36,800

26,800

21,600

26,600

36,400

162,000

39,000

41,200

40,900

30,300

24,100

60,200

5,370,000

September

9,760

12,200

14, 700

15,100

" 13,800

12,800

11,100

10, 100

8,660

8,200

7,600

7,160

7,110

7,340

6,690

5,980

5,580

5,300

5,050

4,800

4,470

4,380

4,290

4,630

4,200

4,370

4,200

3,960

4,220

10,400

2.49

1.72

4.77

3.14

3.03

2.70

2.98

2.72

2.69

2.48

2.43

2.41

2.28

1.41

1.33

1.25

1.00 Z6

.76

.68

.57

.48

.61

1.1-2

.52

.91

.78

.31

.40

1.13

656,000

567, 000

1, 890, 000

1,280,000

1, 130, 000

933,000

893,000

742,000

629,000

549,000

499,000

466,000

438,000

279,000

240,000

202,000

151,000

109, 000

104,000

88,100

68,800

56,800

70,700

140,000

59,000

107, 000

88,500

33,100

45,600

317,000

12,740,000
46 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand CanyonT 

Ariz., Oct. 1, 1929, to Sept. 30, 1941 Continued

1937

Day

1. 

2.-.-

3.-.-

4.-.-

6...-

6-..

7--..

8....

«.---

10---

11...

12...

13...

14---

16---

16---

17-..

18--

19-.-

20-..

21---

22.--'

23--

24--.

26...

26-.-

27---

28---

29. ..

30--.

31.-.

October

Mean 

discharge 

(secondfeet)

13, 900

23, 100

18, 700

10,500

7,750

6,550

6,960

6,720

5,610

5,680

6,740

5,590

5,350

6,260

5,220

6,150

5,100

6,090

5,590

8,340

9,030

7,940

7,810

8,000

7,640

7,860

7,800

7,460

7,210

7,180

7,260

Suspended sedime nt

Mean 

percent

5.44

5.38

8.42

7.54

4.82

3.97

2.73

1.90

1.22

1.08

.76

.70

.51

.41

.34

.29

.26

.23

.24

.49

.84

.67

.59

.87

.90

.90

.70

.57

.49

.64

.54

Tons per 

day

2, 040, 000

3, 360, 000

4, 250, 000

2, 140, 000

1, 010, 000

702, 000

439, 000

293, 000

185, 000

166, 000

118,000

106, 000

73, 700

58,200

47, 900

40,300

34,400

31,600

36, 200

110,000

205, 000

144,000

124, 000

188, 000

186, 000

191,000

147, 000

115, 000

95, 400

124,000

106,000

Monthly load (tons) 16, 870, 000

November

Mean 

discharge 

(secondfeet)

7,180

7,060

6,850

6,840

6,730

6,630

6,660

6,590

6,620

6,640

6,780

7,050

7,570

7,200

7,020

6,760

6,630

6,570

6,500

6,380

6,240

6,220

6,310

6,350

6,390

6,360

6,310

6,410

6,660

6,630

Suspended sediment

Mean 

percent

0.46

.53

.44

.32

.28

.25

.27

.23

.23

.21

21

.29

.34

.30

.26

.24

.26

,32

.26

.24

.19

.17

.16

' .17

.17

.16

.15

.16

.20

.20

Tons per 

day

89, 200

101, 000

8, 1400

59, 100

50,900

44,800

48, 600

40,900

41, 100

37,600

38, 400

55,200

69,500

58, 300

49,300

43, 800

46,500

56,800

45,600

41, 300

32,000

28,500

27, 300

29,100

29,300

27, 500

25, 600

27,700

36,000

35,800

1,398,000

December

Mean 

discharge 

(secondfeet)

6,520

6,480

6,350

6,340

6,180

6,270

6,240

6,090

6,130

6,220

6,410

6,380

6,340

8,600

7,300

6,970

7,420

8,650

8,340

7,870

7,740

7.400

7,020

6,590

6,490

6,240

5,790

5,520

6,320

6,180

5,130

Suspended sediment

Mean 

percent

0.15

.15

.13

.13

.13

.14

.14

.14

.12

.14

.14

.17

.16

.75

.49

.30

.33

.40

.44

.39

.44

.42

.35

.31

.27

.24

.25

.19

.16

.15

.14

Tons per 

day

26,400

26,200

22, 300

22, 300

21, 700

23,700

23,600

23,000

19,900

23,500

24,200

29, 300

27,400

174,000

96,600

56,500

66, 100

92,300

99,100

82, 900

92, 000

83,900

66, 300

55,200

47, 300

40, 400

39, 100

28,300

23, 000

21,000

19,400

1, 497, 000

1938

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.-.

January

5,090

5,090

4.930

4,750

4,630

4,820

5,330

5,540

5,820

5,890

5,750

5,320

4,850

4,580

4,580

4,680

4,970

5,230

5,540

5,910

6,660

7,180

6,950

6,700

6,620

6,360

5,970

5,660

5,390

4,990

4,700

0.11

.11

.10

.10

.10

.11

.09

.11

.13

.13

.14

.12

.09

.08

.07

.07

.08

.10

.12

.15

.16

.24

.28

.23

.19

.17

.14

.14

.13

.12

.10

Monthly load (tons)

15, 100

15, 100

13, 300

12,800

12,500

14, 300

13, 000

16,500

20, 400

20,700

21, 700

17, 200

11, 800

9,890

8,660

8,850

10, 700

14, 100

17,900

23,900

28,800

46,500

52,500

41,600

34,000

29, 200

22,600

21,400

18,900

16,200

12, 700

622. 800

February

5,110

5,490

5,620

5,490

5,620

5,750

6,010

6,010

6,140

6,280

6,140

6,010

5, 880

6,280

7,570

7,720

8,340

8,340

8,020

7,720

7,420

7,120

6,700

6,280

6,010

5,750

5,750

6,010

0.09

.11

.15

.12

.14

.15

.24

.16

.20

.18

.20

.17

.16

.18

.42

.36

.81

.69

.63

.57

.45

.50

.35

.27

.23

.21

.20

.20

12,400

16, 300

22,800

17,800

21,200

23,300

38,900

26, 000

33, 200

30,500

33, 200

27, 600

25,400

30, 500

86, 800

75,000

182, 000

155,000

136, 000

119,000

90, 200

96, 100

63, 300

45,800

37,300

32,600

31,000

32,500

1,541,000

March

6, 700

7,270

11,200

19, 300

39, 100

28,800

24,400

20, 700

18, 400

16,000

14, 400

12,600

- 11,600

11,400

14,400

12,600

12,600

12,200

11, 600

11, 200

11,600

11,800

11,400

11,100

11,200

11,100

11,200

12,600

13, 800

16,400

15, 700

0.27

.38

2.91

3.56

8.76

4.73

3.99

2.88

2.25

1.99

1.70

1.52

1.63

1.18

1.54

1.22

1.16

1.05

.90

.85

.72

.77

.84

.65

.67

.70

.62

.68

.91

1.40

1.22

48,800

74, 600

880, 000

1, 860, 000

9, 250, 000

3, 680, 000

2, 630, 000

1,6U),«)0

1, 120, 000

860, 000

661,000

517,000

511, 000

363,000

599, 000

415,000

395, 000

346,000

282, 000

257,000

226,000

245,000

259, 009

195,000

203, 000

210, 000

187, 000

231,000

339, 000

620,000

517,000

29, 590, 000
QUANTITIES OF SUSPENDED SEDIMENT 47

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of sus~ 

pended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 80, 1941 Continued

1938

Day

1-..-

2....

3....

4....

5.--.

6....

7....

8_.__

t)-.__

10...

11...

12. _.

13. ..

14...

15...

16...

17...

18...

19...

20...

21_..

22...

23...

24...

25. .-

26...

27...

28...

29-.-

30...

31

April

Mean

discharge

(secondfeet)

14,600

13,400

12,200

11, 200

10, 300

9,490

9,150

9,830

10, 300

10, 500

11,200

11,200

10, 700

10,900

13,200

17,900

20, 700

21,000

18, 700

18,200

23, 400

36,600

43,400

47,400

53, 100

56,400

62,000

66, 100

65,500

57,400

Suspended sediment

Mean

percent

1.08

.90

.68

.65

.60

.51

.44

.53

.55

.59

.64

.57

.47

.49

.55

1.18

1.46

1.58

1.30

1.06

1.72

2.38

2.94

2.92

2.44

2.57

2.81

2.51

2.20

2.22

Monthly load (tons)

Tons per

day

426,000

326,000

224,000

197, 000

167, 000

131, 000

109, 000

141, 000

153, 000

167, 000

194, 000

172, 000

136, 000

144, 000

196, 000

570, 000

816, 000

896, 000

656, 000

521, 000

1, 090, 000

2, 350, 000

3, 450, 000

3, 740, 000

3, 500, 000

3, 910, 000

4, 700, 000

4, 480, 000

3, 890, 000

3, 440, 000

40,890,000

May

Mean

discharge

(secondfeet)

58,600

63,700

65, 500

69, 200

62, 600

56,900

53, 100

46, 900

41, 100

37, 000

33,600

30, 500

28,300

26,900

26, 300

28,300

36,600

51, 500

63, 700

68,600

68, 600

70, 500

68,600

67,400

66, 100

59, 100

55, 300

54,700

58, 000

66,100

74,400

Suspended sediment

Mean

percent

2.00

2.00

1,52

1.48

1.46

1.46

1.32

1,16

1.00

.95

.80

.70

.51

.44

.44

.54

.78

1.31

1.45

1.43

1.20

1.27

1.22

1.04

1.04

.90

.88

.82

.82

.86

1.11

Tons per

day

3, 160, 000

3, 440, 000

2, 690, 000

2, 770, 000

2, 470, 000

2, 240, 000

1, 890, 000

1, 470, 000

1, 110, 000

949, 000

726, 000

576, 000

390, 000

320,JWO

312,000

413, 000

771, 000

1,820,000

2, 490, 000

2, 650, 000

2,220,000

2, 420, 000

2, 260, 000

1, 890, 000

1, 860, 000

1, 440, 000

1, 310, 000

1, 210, 000

1, 280, 000

1, 530, 000

2, 230, 000

52,310,000

June

Mean

discharge

(secondfeet)

85,400

94, 900

95,600

94, 100

93, 400

95,600

99,400

98, 700

98, 700

94, 100

87, 500

84, 000

79,200

76,400

73, 100

77, 100

79,200

71,200

66, 700

63, 700

63, 100

61, 400

58,600

62, 000

73, 100

73,800

68,600

63, 100

62,600

64,900

Suspended sediment

Mean

percent

0.92

.90

1.10

.88

.84

.72

.74

.71

.68

.79

.66

.50

.68

.64

.69

.66

.54

.64

.56

.52

.51

.62

.52

.63

.60

.84

.56

.48

.40

.73

Tons per

day

2, 120, 000

2,310,000

2,840,000

2, 240, 000

2, 120, 000

1, 860, 000

1,990,000

1, 890, 000

1, 810, 000

2, 010, 000

1, 560, 000

1, 130, 000

1, 450, 000

1, 320, 000

1,360,000

1, 370, 000

1, 150, 000

1, 230, 000

1, 010, 000

894,000

869, 000

1, 030, 000

823,000

1, 050, 000

1, 180, 000

1, 670, 000

1,040,000

818,000

676,000

1,280,000

44,100,000

1938

July

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...

60,200

60,200

63, 100

56,400

50,500

45, 900

43^000

40,100

36,600

33,200

30,200

28,000

25,900

24,600

22,700

' 20,900

19,800

20,400

20,400

19,500

18, 700

17,300

16, 300

16, 100

15, 300

14,600

14,200

13, 300

12,600

12,000

12,000

0.74

.96

1.00

.76

.46

.43

.40

.32

.29

.32

.26

.22

.20

.18

.16

.16

.13

.14

.15

.18

.24

.35

.31

.23

.18

.19

.19

.19

.16

.14

.13

Monthly load (tons) -

1, 200, 000

1, 560, 000

1, 700, 000

1, 160, 000

627, 000

533,000

464,000

346,000

287, 000

287, 000

212, 000

166, 000

140, 000

120, 000

98, 100

90,300

69,500

77, 100

82,600

94,800

121, 000

163, 000

136,000

100, 000

74,400

74, 900

72,800

68,200

54,400

45,400

42,100

10, 270, 000

August

11, 300

10,900

11,300

10,900

10, 200

9,680

9,030

8,870

10,400

10,200

10, 000

9,030

9,350

12, 200

10,700

10,000

9,680

11,600

10, 700

9,510

8,550

7,800

7,070

6,650

6,230

5,960

5,570

5,440

5,180

5,050

4,790

0.12

.17

.17

.16

1.14

.12

.11

.09

.15

1.24

1.78

.84

.55

.38

.76

.86

.81

.60

1.64

1.92

1.26

.95

.64

1.04

.82

.56

.34

.26

.34

.20

.19

36,600

50,000

51,900

47, 100

38,600

31,400

26,800

21, 600

42, 100

341,000

481,000

205,000

139, 000

125, 000

220,000

232, 000

212, 000

188,000

474, 000

493,000

291,000

200,000

122, 000

187, 000

138, 000

90,100

51,100

38,200

47,600

27, 300

24,600

4,673,000

September

5,570

6,230

8,400

15, 000

19,300

22, 500

25,400

21, 000

21, 300

21,000

22,200

22,500

21,000

20,100

22,200

 23,400

19,600

17,300

16,800

15,000

13,800

12,800

12,000

11,300

10,700

10,000

9,510

9,200

9,030

8,550

0.13

.14

.62

3.72

3.04

4.34

3.97

2.94

2.65

2.59

2.28

3.01

3.56

2.82

2.80

2.68'

2.20

1.58

1.67

1.46

1.18

1.33

.86

.78

.67

.44

.34

.27

.24

.20

19,600

23,500

141, 000

1, 510, 000

1, 580, 000

2,640,000

2,720,000

1, 670, 000

1, 520, 000

1,470,000

1,370,000

1, 830, 000

2, 020, 000

1, 530, 000

1,680,000

1,'690, 000

1,160,000

738,000

758,000

591, 000

440,000

460,000

279, 000

238,000

194,000

119, 000

87,300

67,100

58,500

46,200

28, 650, 000

Estimated.
48 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 80, 1941 Continued

1938

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_. .

October

Mean 

discharge 

(secondfeet)

8,070

7,830

7,660

7,770

7,140

7,040

6,870

6,890

6,620

6.580

8,760

12,400

11,800

12,500

12,100

11,300

12,100

12,000

11,000

10,500

10,200

10,300

10,600

11,100

10,800

' 10,400

10,100

9,820

9,870

9,530

9,220

Suspended sediment

Mean 

percent

0.18

.19

.17

.15

.19

.16

.29

.17

.15

.16

.20

.39

.67

.70

.52

.61

.76

.67

.45

.62

.51

.40

.50

.42

.48

.46

.35

.32

.34

.28

.34

Monthly load (tons)

Tons per 

day

39,200

40,200

35,200

31,500

36,600

30, 400

53,800

31, 600

26.800

28,400

47,300

131, 000

213,000

236,000

170,000

186,000

248,000

217,000

134,000

176, 000

140,000

111,000

143,000

126,000

140, 000

129.000

95,400

84,800

90,600

72,000

.84,600

3, 328, 000

November

Mean 

discharge 

(secondfeet)

9,000

8,790

8,740

8,820

8,520

8,440

8,690

9,010

9,270

9,140

9,050

9,010

8,970

8,650

8,840

9,010

9,140

8,970

8,680

8,100

7,950

' 8,130'

8,100

7,980

7,680

7,540

7,400

7,100

6,680

6,160

Suspended sediment

Mean 

percent

0.20

.19

.22

.17

.16

.15

.13

.14

.14

.13

.13

.12

.12

12

.14

.14

.14

.12

.10

.09

.08

.07

.07

.07

.07

.06

.06

.06

.05

.05

Tons per 

day

48,600

45, 100

51,900

40,500

36,800

34, 200

30,500

34,100

35,000

32, 100

31,800

29,200

29,100

28,000

33,400

34,100

34,500

29,100

23,400

19,700

17,200

15,400

15,300

15,100

14, 500

12,200

12,000

11,500

9,020

8,320

811, 600

December

Mean 

discharge 

(secondfeet)

5,900

5,300

5,120

5,350

5,880

6,340

6,620

6,870

7,150

7,220

7,650

8,370

8,430

8,260

8,200

8,280

8,380

8,130

7,640

7,250

6,800

7,080

7,520

7,620

7,350

7,320

7,270

7,040

6,610

5,910

5,010

Suspended sediment

Mean 

percent

0.04

.03

.02

.03

.03

.04

.05

.05

.06

.07

.07

.09

.10

.08

.08

.08

.09

.08

.07

.06

.06

.04

.07

.10

.08

.08

.09

.06

.05

.05

.04

Tons per

day

6,370

4,290

2,760

4,330

4,760

6,850

8,940

9,270

11,600

13,600

14,500

20,300

22,800

17,800

17,700

17,900

20.400

17,600

14,400

11,700

11.000

7,650

14,200

20,600

15,900

15,800

17,700

11,400

8,920

7,980

5.410

384, 400

1939

!.__.

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..-

Jannary

4,750

4,740

4,610

4,450

4,410

4,800

5,360

5,600

5,610

5,790

6,050

6,260

6,270

6,310

6,120

6,060

6,090

6,130

6,050

6,120

5,930

6,170

6,020

6,170

6,690

6,760

6,610

6,480

6,450

6,580

6,430

0.04

.03

.03

.03

.03

.03

.02

.03

.04

.04

.04

.04

.04

.04

.05

.05

.04

.04

.04

.04

.04

.03

.03

.04

.04

.07

.06

.05

.05

.04

.05

Monthly load (tons)

5,130

3,840

3,730

3,600

3,570

3,890

2,890

4,540

6,060

6,250

6,530

6,760

6,770

6,810

8,260

8,180

6,580

6,620

6,530

6,610

6,400

5,000

4,880

6,660

7,230

12,800

10, 700

8,750

8,710

7,110

8 680

2CO, 100

February

5,920

5,820

5,950

5,920

5,790

5,690

5,400

5,090

5,060

5,060

5,410

5,880

5,910

5,610

5,340

5,230

5,350

5,740

6,040

6,050

5,930

6,050

6,160

6,060

6,080

5. 910

5 8"0

5,870

0.04

.04

.03

.04

.04

.04

.04

.03

'.03

.03

.02

.03

.04

.03

.03

.03

.02

.02

.04

.04

.04

.04

.04

.06

.09

.08

.06

.07

6,390

6,290

4,820

6,390

6,250

6,150

5,830

4,120

4,100

4,100

2,920

4,760

6,880

4,540

4,330

4,240

2,890

3,100

6,520

6,530

6,400

6,530

6,650

9,820

14,800

12,800

9,440

11,100

178. 200

March

6,040

6,050

6,020

6,050

6,040

6,150

6,240

6,160

6,130

6,080

5,980

6,100

6,650

7,540

8,460

9,240

10,000

10,400

10,600

10,900

11.200

12,000

21,100

27,400

27,300

28,500

28, 000

27, 000

27.500

28,000

27,800

0.08

.08

.06

.07

- .06

.05

.05

.06

.06

.06

.06

.06

.07

.10

.17

.28

.34

.54

.60

.68

.89

1.07

1.82

1.84

1.92

2.06

". 12

1.83

1.66

1.50

1.45

13, 000

9,800

9,750

1 1, 400

9,780

8,300

8,420

10,000

9,930

9,850

9,690

9,880

12,600

20,400

38,800

69,900

91,800

152,000

172,000

200,000

269,000

347,000

1,040,000

1, 360, 000

1. 420, 000

1,590,000

1,600,000

1,330,000

1, 230, 000

1, 130, 000

1,090,000

13,2^0 000

1 Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 49

TABLE 9. Mean daily discharge, mean daily concentration, and dailv load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1939

Day

1 ...

2.....

3.....

4.....

5__-_

6..-

7

8_-._

g

10...

ll...

12...

13...

14...

15...

16...

17...

18...

19...

20...

21...

22...

23-.-

24...

25...

26.. .

27...

28...

29...

30...

31

April

Mean 

discharge 

(secondfeet)

25,500

23, 700

22,000

20,300

19,500

 21, 900

23,800

25,400

24,800

24, 000

22,600

21,800

22,000

21,500

20,200

18,700

18, 100

18,500

18,200

17,200

16,300

15,800

15,300

15,500

16,100

16,800

20,300

21,800

21,000

21,900

Monthly ;

Suspended sediment

Mean 

percent

1.24

1.10

1.05

.98

.88

1.60

1.68

1.36

1.28

.90

.83

.64

.64

.58

.58

.47

.47

.43

.38

.36

.30

.24

.30

.26

.26

.32

.58

.54

.42

.56

oad (tons)

Tons per 

day

854, 000

704, 000

624, 000

537,000

463,000

946,000

1, 080, 000

933,000

857,000

583,000

506, 000

377,000

380,000

337, 000

316, 000

237,000

230,000

215,000

187,000

167, 000

132,000

102, 000

124,000

109,000

113,000

145,000

318, 000

318,000

238,000

331, 000

12, 460, 000

May

Mean 

discharge 

(secondfeet)

22,500

24,200

29,600

33,400

37,000

39,800

40,600

42,600

45,300

44,400

40,800

39, 500

40,100

41, 100

42,600

41,500

38,400

38, 000

39, 300

39,400

38, 100

37, 500

40,700

44,400

46,600

48,100

46,600

42,600

39,600

36,000

33, 700

Suspended sediment

Mean 

percent

0.53

.67

.84

.94

1.04

1.13

1.12

1.14

1.17

.95

.94

.90

.77

.77

.79

.67

.66

.73

.63

.61

.58

.55

.69

.80

.75

.67

.69

.63

.54

.44

.43

Tons per 

day

322, 000

438,000

671,000

848,000

1, 040, 000

1,210,000

1, 230, 000

1,310,000

1, 430, 000

1, 140,000

1, 040, 000

960,000

834, 000

854,000

909,000

751, 000

684,000

749, 000

668,000

649,000

597,000

557,000

758, 000

959,000

944,000

870,000

868,000

725,000

577, 000

428,000

391,000

25, 410, 000

June

Mean 

discharge 

(secondfeet)

32,800

34,600

37,900

39,300

40,300

37,500

37,400

39,900

41,200

39, 000

36,500

34,400

31,900

29,400

28,000

27,100

26,800

27,000

26,600

24,600

23,500

21,900

20, 100

18,500

16,300

14,900

14,100

13,900

13,900

13,600

Suspended sediment

Mean 

percent

0.40

.41

.44

.47

.52

.54

.53

.57

.52

.47

.37

.34

.32

.27

.25

.27

.30

.31

.26

.24

.20

.20

.20

.13

.14

.10

.08

.09

.10

.10

Tons per 

day

354,000

383, 000

450,000

499,000

566,000

547,000

535,000

614,000

578, 000

495,000

365,000

316, 000

276,000

214,000

189,000

198,000

217,000

226,000

187,000

159,000

127,008

118,000

109,000

64,900

61,600

40,200

30,500

33,800

37,500

36,700

8,027,000

1939

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...

July

13,400

13,000

12,400

11,700

11,200

10,600

10,200

9,820

9,370

9,130

8,680

8,270

7,880

7,650

7,400

7,050

6,990

6,720

6; 410

6,040

5,690

5,430

5,190

5,040

4,820

4,720

4,520

4,350

4,240

4,040

4,000

0.09

.07

.06

.06

.04

.05

.04

.04

.04

.04

.04

.03

.03

.02

.02

.03

.02

.03

.02

.02

.02

.03

.02

.02

.02

.02

.02

.01

.01

.01

.01

Monthly load (tons)"!.

32,600

24,600

20,100

19,000

12,100

14,300

11,000

10,600

10,100

9, 860

9,370

6,700

6,380

4,130

4,000

5,710

3,770

5,440

3,460

3,260

3,070

4,400

2,800

2,720

2,600

2,550

2,440

1,170

1,140

1,090

1,080

241, 500

August

3,980

3,920

3,580

3,550

3,490

3,730

4,570

4,930

4,930

4,930

4,690

4,620

5,400

5,010

5,230

5,380

4,920

4,570

4,270

3,900

3,580

3,400

3,240

3,100

3,020

2,910

2,830

2,880

2,890

2,790

2,850

0.01

.01

.01

.01

.05

.08

.02

.01

.29

.53

.16

.14

.23

.11

.12

.28

.11

.20

.25

.21

.15

.14

.10

.07

.07

.07

.05

.05

.09

.16

.05

-------.---. _ -------

1,070

1,060

967

958

4,710

8,060

2,470

1,330

38,600

70, 500

20,300

17,500

33,500

14, 900.

16,900

40,700

14, 600

24,700

28,800

22,100

14,500

12,900

8,750

5,860

5; 710

5,500

3,820

3,890

7,020

12,100

3,850

447,600

September

2,890

3,670

3,880

3,860

5,140

7,640

8,540

10,300

12,200

11,100

13,200

13,800

' 17, 300

25,200

18,100

14,800

15,600

12,600

11,600

10,700

9,970

9,130

8,250

7,720

7,080

6,720

6,300

6,640

8,630

7,380

0.07

.36

.35

.15

.68

.52

1.65

1.84

4.76

2.30

1.58

4.33

4.66

6.37

5.70

3.82

3.75

2.36

1.44

1.39

1.58

1.44

1.36

.99

.61

.60

.49

.42

.45

.39

------------ _ -------

5,460

35, 700

36,700

15,600

94,400

107, 000

380,000

512,000

1,570,000

689,000

563,000

1, 610, 000

2, 180, 000

4,330-000

2, 790, 000

1, 530, 000

1, 580, 000

803,000

451,000

402,000

425,000

355,000

303,000

206,000

117, 000

109, 000

83,300

75,300

105, 000

77,700

21, 540, 000
50 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 30, 1941 Continued

1939

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...

October

Mean 

discharge 

(secondfeet)

5,870

5,750

5,950

5,820

5,930

5,870

5,830

5,750

5,650

5.690

5,700

5,870

5,970

6,330

6.470

6,300

6,500

6,480

6,190

6,040

5,950

5,870

5,660

5,440

5,380

5,220

5,080

5,020

4,980

4,980

4,840

Suspended sediment

Mean 

percent

0.42

.84

.50

.30

.27

.32

.29

.22

.17

.14

.15

.14

.12

.12

.16

.15

.16

.17

.17

.26

.20

.16

.12

.24

.18

,.18

.12

.10

.09

.08

.08

Monthly load (tons)_

Tons per 

day

66,600

130,000

80,300

47,100

47,100

50,700

45,600

34,200

25,900

21,500

23,100

22,200

19,300

20,500

28,000

25, 500

28,100

29,700

28,400

42,400

32,100

25,400

18,300

35,300

26,100

25,400

16,500

13,600

12,100

10,800

10,400

1,042,000

November

Mean 

discharge 

(secondfeet)

5,100

5,470

5,450

5,340

5,390

5,340

5,310

5,340

5,470

5,560

5,710

5,900

5,990

6,060

6,220

6,090

6,020

5,920

5,710

5,730

5,710

5,690

5,650

5,540

5,340

5,340

5,190

5,190

5,240

5,260

Suspended sediment

Mean 

percent

0.08

.08

.10

.09

.09

.09

.09

.10

.10

.09

.09

.10

.10

.10

.12

.10

.10

' .09

.08

.08

.07

.08

.07

.07

.06

.06

.06

.06

.06

.07

Tons per 

day

11,000

11,800

14,700

13,000

13,100

13,000

12,900

14, 400

14,800

13,500

13,900

15,900

16,200

16,400

20,200

16,400

16,200

14, 400

12,300

12,400

10,800

12,300

10,700

10,500

8,650

8,650

8,410

8,410

8,490

9,940

383, 400

December

Mean 

discharge 

(secondfeet)

5,280

5,320

5,320

5,310

5,450

5,480

5.360

5,340

5,300

5,230

5,130

5,150

5,170

5,170

5,180

5,190

5,220

5,240

5,140

5,060

5,020

4,890

4,870

4,840

4,930

4,860

4,570

4,170

4,160

4,320

4,340

Suspended sediment

Mean 

percent

0.06

.06

.06

.06

.05

.06

.05

.06

.06

.06

.06

.06

.06

.06

.07

.05

.06

.06

.06

.07

.08

.08

.07

.06

.06

.06

.06

.08

.09

.11

.10

Tons per 

day

8,550

8,620

8,620

8,600

7,360

8,880

7,240

8,650

8,o90

8,470

8,310

8,340

8,380

8,380

9,790

7,010

8,460

8,490

8,330

9,560

10,800

10,600

9,200

7,840

7,990

7,870

7,400

9,010

10,100

12,800

11,700

273.900

1940

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...

January

3,980

3,610

3,360

3,430

3,560

3,740

4,220

5,130

5,350

5,"390

5,620

5,820

5,880

6,360

7,170

6,580

6,010

5,870

5,580

5,050

4,460

4,000

3,560

2,870

2,660

3,130

3,440

3,510

3,870

4,360

4,670

0.04

.04

.04

.04

.04

.04

.04

.07

.07

.09

.09

.10

.10

.13

.63

.18

.21

.21

.16

.12

.11

.10

.10

.07

.04

.04

.04

.06

.06

.07

.07

Monthly load (tons).

4,300

3,900

3,630

3,700

3,840

4,040

4,560

9,700

10, 100

13, 100

13,700

15, 700

15,900

22,300

122,000

32,000

34,100

33,300

24,100

16,400

13,200

10,800

9,610

5,420

2,870

3,380

3,720

5,690

6,270

8,240

8,830

468,400

February

4,720

5,000

5,410

5,800

6,870

7,350

7,400

7,030

6,750

6,410

6,090

5,750

5,600

5,520

5,470

5,310

5,320

5,390

5,270

5,150

5,120

5,150

5,180

5,010

4,880

4,980

5,180

5,390

5,360

0.10

.08

.08

.08

.18

.19

.57

.53

.41

.34

.29

.21

.20

.18

.16

.14

.12

.11

.10

.10

.08

.07

.07

.07

.06

.08

.07

.07

.09

__ _ -_.-__ __ . ....

12,700

10,800

11,700

12,500

33, 400

37,700

114, 000

101,000

74,700

58,800

47,700

32,600

30,200

26,800

23,600

20, 100

17,200

16,000

14,200

13,900

11, 100

9,730

9,790

9,470

7,910

10,800

9,790

10,200

13,000

801, 400

March

5,650

7,820

8,790

8,610

8,000

7,520

6,990

8,320

9,000

8,580

8,930

8,520

8,120

7,920

8,260

7,820

7,460

7,200

6,990

6,650

6,290

6,270

6,450

6,500

6,640

6,710

6,940

7,280

8,020

8,460

9,050

0.14

.24

.36

.95

.87

.68

.57

.56

.55

.41

.44

.45

.36

.32

.30

.45

.35

.28

.24

.21

.18

.16

.16

.17

.17

.20

.18

.18

.30

.32

.38

21,400

50,700

85,400

221,000

188,000

138,000

108,000

126,000

134,000

95,000

106,000

104,000

78,900

68,400

66,900

95,000

70,500

54,400

45,300

37,700

30,600

27,100

27,900

29,800

30,500

36,200

33,700

35,400

65,000

73,100

92,900

2, 377, 000
QUANTITIES OF SUSPENDED SEDIMENT 51

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. SO, 1941 Continued

1940

Day

l-__.

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

Mean

(secondfeet)

9,260

10, 200

10, 300

9,800

9,530

9,580

9,870

9,920

9,210

8,810

9,220

9,240

9,400

9,130

8,580

8,480

8,520

8,710

9,300

9,830

10,600

10,900

10,600

11,200

16, 100

19,100

19,600

20,700

21,600

22,000

Suspended sediment

Mean

percent

0.38

.48

.46

.44

.36

.35

.42

.41

.42

.30

.43

.43

.48

.38

.35

.33

.29

.26

.28

.38

.42

.50

.42

.50

.99

1.17

1.14

1.25

1.05

.97

Monthly load (tons)

Tons per

day

94, 900

132, 000

128,000

116, 000

92,600

90,500

112,000

110, 000

104,000

71, 400

107, 000

107, 000

122,000

93,700

81,100

75,600

66,700

61, 100

70,300

101,000

120,060'

147,000

120,000

151, 000

430,000

603,000

603,000

699, 000

610, 000

576,000

5, 996, 000

May

Mean

(secondfeet)

23,100

22,900

22,900

21, 400

20,000

18, 900

19, 100

22, 800

ft6, 300

t7,200

|1, 400

1,800

2, 900

6, 700

4,400

2,100

4,400

5,500

4,400

4,600

3,900

0,600

7,800

6,900

4,800

3,300

2, 100

1,700

2, 100

2,800

3, 100

Suspended sediment

Mean

percent

1.00

.99

.77

.79

.69

.66

.67

.68

1.02

.86

1.09

1.19

1,10

1.26

1.20

1.19

1.13

1.28

 1.17

1.22

.96

.88

.80

.78

.64

.57

.60

.52

.55

.56

.48

Tons per

day

624,000

612, 000

476,000

456, 000

373, 000

337,000

346, 000

419,000

724, 000

632,000

924,000

1,020,000

977, 000

1, 250, 000

1,120,000

1, 350, 000

1,360 000

1 570 000

1 400 000

1 470 000

1,140 000

965. 000

816 000

777 000

601 000

512 000

520, 000

445,000

477, 000

496, 000

429, 000

24, 620, 000

June

Mean

discharge 

(secondfeet)

34,500

34, 500

36,500

39, 500-

41,600

41,200

39,900

37,400

34,600

32,200

30,700

28,400

25,900

23,300

21,600

20, 400

19, 900

20,200

20, 700

20, 400

19, 100

18,800

18, 000

16,900

16, 200

15, 700

15,400

14, 700

14, 100

13,400

Suspended sediment

Mean

percent

0.69

.65

.58

.59

.70

.65

.54

.62

.54

.53

.42

.36

.26

.23

.20

.18

.15

.19

.21

.18

.20

.15

.14

.13

.12

.09

.10

.11

.08

.08

Tons per,

day

643, 000

605,000

572, 000

629,000

786,000

723,000

582, 000

626,000

504,000

461,000

348,000

276,000

182,000

145,000

117,000

99,100

80 600

104 000

117 000

99. 100

103. 000

76,100

68.000

59.300

52.500

38 200

41,600

43, 700

30,500

28,900

8, 241, 000

1940

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...

July

12,500

11,600

11,200

12,000

10,500

9,610

9,430

8,660

7,980

7,580

7,380

7,060

6,620

6,240

6,080

5,800

5,500

5,190

4,840

4,660

4,920

5.470

6,120

4,980

4,480

4,430

4,660

7,070

5,740

4,600

5,340

0.08

.07

.06

.10

.08

.07

.06

.22

.32

.40

.14

.10

.08

.07

.06

.05

.04

.05

.05

.04

.03

.02

.03

.04

.10

.09

.10

.23

2.93

2,01

1.24

Monthly lond (tons) .

27,000

21,900

18,100

32, 400

22,700

18,200

15, 300

51,400

68,900

81,900

27,900

19, 100

14,300

11,800

fl,850

7,830

5,940

7,530

6,530

5,030

3,990

2,950

4,960

5,380

12,100

10,800

12,600

43, 900

454,000

250,000

179, 000

1. 453. 000

August

6, 440

5, 320

4,260

3, 630

13,310

3, 130

12,980

12,850

|2, 740

ft 600

2,460

2,390

2,320

2,350

P.570

13,220

15,060

3, 330

2,990

2,570

2,410

2,380

3,100

4,940

7,890

6,990

7,730

9,230

7,130

5, 390

4,830

0.40

.68

1.94

2.26

2.14

1.70

1.28

.84

.49

.23

.22

..18

.12

.09

.06

.05

2.26

4.94

3.06

2.64

1.14

.68

1.32

4.93

5,12

5.87

5.48

3.98

4.65

4.57

3.77

67,600

97, 700

223,000

222,000

191,000

144, 000

103,000

64,600

36. 300

16, 200

14,600

11,600

7,520

5,710

4,160

4,350

309, 000

444,000

247,000

183,000

74,200

43, 700

110, 000

658,000

1,090,000

1,110,000

1,140,000

992,000

895,000

665, 000

492,000

9, 666, 000

September

5,430

5,260

5,530

5,480

5,430

5,210

6,030

5,020

4,400

4,600

4,110

3,760

3,680

7,270

8,980

6,200

5,530

8,690

11, 300

11, 400

12, 700

13,200

13, 300

14,200

14, 100

11,200

.9,650

9,030

8,900

11,900

2.76

* 2.21

1.58

1.30

1.02

1.25

1.14

.92

4.70

1.55

.60

1.02

.54

.87

4.83

5.24

3,12

1.90

4.97

4.57

4.25

3.44

4.96

3.56

3.96

3.28

3.42

2.88

2.10

2.78

405,000

314, 000

236,000

192, 000

150,000

176,000

186, 000

125,000

558,000

192,000

66,600

104,000

53, 700

171,000

1, 170, 000

877,000

466,000

446,000

1, 520, 000

1,400,000

1,460,000

1,230,000

1,780,000

1,360,000

1,510,000

992,000

891,000

702,000

505,000

f 893, 000

20,130,000
52 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of sus- 

> pended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 30, 1941 Continued

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...

October

Mean

(secondfeet)

22, 300

26,200

19,200

17,200

16,900

18,800

23,100

17,700

17,300

17,000

14,400

13,000

12,000

11,400

10,600

9,850

9,300

8,920

8,520

8,070

7,680

7,440

7,300

7,110

6,890

6,800

6,870

6,680

7,070

7,920

8,190

Suspended sediment

Mean

percent

8.06

7.05

4.61

4.14

2.86

4.17

4.33

3.62

3.29

2.82

1.67

1.44

1.38

1.08

1.03

1.80

.75

.70

.66

.58

.66

.48

.34

.34

.31

.26

.24

.25

.84

.48

.51

Monthly load (tons).

Tons per

day

4, 850, 000

4, 990, 000

2, 390, 000

1, 920, 000

1, 300, 000

2, 120, 000

2, 700, 000

1, 730, 000

1, 570, 000

1, 290, 000

649,000

505,000

447,000

332,000

295,000

213, 000

188,000

169,000

152, 000

126, 000

137,000

96,400

67,000

65,300

57,700

47, 700

63, 100

45, 100

160,000

103, 000

113, 000

28,900,000

November

Mean

discharge 

(secondfeet)

8,750

8,310

7,360

6,970

6,860

6,750

6,490

6,440

6,760

6,830

6,770

6,550

6,410

6,450

6,520

6,610

6,660

6,360

6,140

6,220

9,810

10,500

8,770

7,700

7,860

7,650

7,350

7,200

7,070

6,770

Suspended sediment

Mean

percent

aW.60

.59

.54

.56

.54

.47

.40

.34

.28

.26

.24

.20

.25

.20

.22

.21

.17

.16

.15

.50

.85

.99

.83

.88

.76

.52

.43

.38

.31

Tons per

day

154, 000

135,000

117,000

102, 000

104, 000

98,400

82, 400

69,600

62,100

51,600

47, 500

42, 400

34,600

43, 500

35,200

39, 300

35,100

29,200

26,500

25,200

132,000

241,000

284,000

173, 000

187, 000

157, 000

103,000

83,600

72,500

56,700

2, 774, 000

December

Mean

discharge 

(secondfeet)

6,590

6,410

6,200

6,020

6,020

6,090

6,080

6,130

6,270

6,440

6,420

6,410

7,030

7,540

7,770

8,250

7,580

6,910

5,910

4,830

4,300

5,940

5,320

5,320

7,520

6,720

9,140

8,740

7,560

7,110

7,140

Suspended sediment

Mean

.percent

0.28

.23

.24

.18

.15

.16

.18

.16

.16

.16

.20

.28

.20

.32

.25

.69

.62

.37

.32

.32

.24

'.54.34

.50

.94

.94

2.09

1.56

1.41

1.55

.84

Tons per

' day

49,800

39,800

40,200

29,300

24,400

26, 300

29,500

26,500

27,100

27,800

34,700

48,500

38,000

65,100

52,400

154,000

127,000

69,000

51,100

41,700

27,900

54,500

77,600

71,800

191, 000

171,000

516,000

368,000

288,000

298,000

162, 000

3,227,000

1941

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...

January

7,940

10,600

11,300

9,700

8,170

7,340

6,690

6,330

5,930

5,610

5,340

5,540

13,500

7,590

6,630

6,730

6,790

6,910

6,490

6,220

5,880

5,540

5,320

5,310

5,520

6,290

6,380

6,980

7,010

6,650

6,410

Monthly It

0.85

1.95

2.66

1.92

1.12

.95

«.80

.66

.50

.36

.30

.22

9.87

3.44

1.63

1.10

.78

.88

.64

.64

.52

.39

.30

.26

.28

.38

.35

.38

.49

.45

.43

ad (tons) -

182,000

558,000

812, 000

503,000

247,000

188,000

144,000

113,000

80,100

54,500

43,300

32,900

3,600,000

705,000

292,000

200,000

148,000

164,000

112,000

108,000

82,600

58,300

43,100

37, 300

41, 700

64, 500

60, 300

- 71, 600

92,700

80,800

74,400

5, 499, 000

February

6,490

6,590

6,580

6,440

6,410

6,410

6,280

6,020

5,800

6,370

7,040

6,760

6,730

6,870

7,920

7,890

8,090

9,060

11, 300

10,800

11,300

11,600

14,800

16,900

16, 100

14,900

14,300

13,700

0.38

.43

.38 .34-

.35

.34

.35

.27

.27

.27

.78

.65

.60

.74

.89

..90

.74

.68

1.64

1.45

1.33

1.35

2.19

2.65

2.17

2.02

1.88

1.97

66,600

76,500

67,500

59,100

60,600

58,800

59,300

43,900

42,300

46,400

148,000

119, 000

109,000

137, 000

190,000

192,000

162,000

166,000

500,000

423,000

406,000

423, 000

875, 000

1, 210, 000

943,000

813, 000

726,000

729,000

8,851,000

March

13,600

13,400

13,300

12,600

12,600

14,000

12,800

12, 100

11, 700

11,100

10,100

9,540

9,050

8,720

8,410

22,100

19,100

15,100

14,000

13,500

13,100

13, 100

13,200

13, 100

15, 000

14,900

16,000

17, 100

18,000

16,500

15,600

1.58

. 1.48

1.42

1.27

1.24

1.29

1.05

.90

.82

.72

.79

.66

.56

.59

.48

6.28.

3.40

2.83

2.44

2.04

1.85

1.76

1.70

1.64

11.70

11.70

1.94

2.29

1.86

1.61

1.35

580,000

535,000

510,000

432,000

422,000

488,000

363,000

294,000

259,000

' 216,000

215,000

170, 000

137, 000

139,000

109,000

3,750,000

1, 750, 000

1, 150, 000

922,000

744,000

654,000

623,000

606,000

580,000

688,000

684,000

838,000

1, 060, 000

904,000

717,000

569,000

21, 110, 000

i Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 53

TABLE 9. Mean daily discharge, mean daily concentration, and daily load of suspended sediment in the Colorado River at gaging station near Grand Canyon, 

Ariz., Oct. 1, 1929, to Sept. 80, 1941 Continued

1941

Day

1

2....

3....

4....

5...-

$

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

]V

April

Mean 

discharge 

(secondfeet)

15,800

15,700

16,300

18,100

20,000

19, 300

18,500

18,000

18,600

19,600

19, 700

19,800

21, 700

22,900

23,400

22,200

21,400

20,900

20,200

20,000

19,400

19,100

18,300

17,100

18,500

20,500

20,600

21,800

29,300

33,000

[onthly lo£

Suspended sediment

Mean 

percent

1.33

1.24

1.36

1.54

2.17

1.92

2.00

1.46

i 1. 50

1.54

1.36

1.24

1.32

1.60

1.79

1.33

1.45

1.34

I.JO

.95

.88

.69

.72

.66

.59

.87

1.90

1.00

2.18

2.44

,d (tons)..

Tons per 

day

567, 000

526,000

599, 000

753,000

1, 170, 000

1,000,000

999,000

710,000

753, 000

815, 000

723,000

663,000

773, 000

989,000

1, 130, 000

797,000

838,000

756,000

600,000

513,000

461,000

356,000

356,000

305,000

295,000

482,000

501,000

589,000

1, 720, 000

2, 170, 000

22, 910, 000

May

Mean 

discharge 

(secondfeet)

39,900

40, 100

41,300

44,600

50,900

56,900

76,800

73,600

73, 300

76,400

79,200

82, 700

86,800

92,300

101, 600

112, 500

119,200

114,500

103, 700

99,100

99,200

94,800

83, 500

76,600

80,100

83,100

82, 700

84,900

86,700

87,500

84,200

Suspended sediment

Mean 

percent

1.94

2.64

12.00

1.57

1.59

1.79

2.92

1.99

1.68

1.43

1.68

1.87

1.55

1.38

1.34

1.47

1.45

1.17

1.06

1.18

.96

.83

.70

.76

.92

1.28

1.86

1.42

1.18

.91

.90

Tons per 

day

2, 090, 000

2,860,000

2, 230, 000

1, 890, 000

2, 180, 000

2, 750, 000

6, 050, 000

3,950,000

3, 320, 000

2, 950, 000

3, 590, 000

4,180,000

3, 630, 000

3, 440, 000

3, 680, 000

4, 470, 000

4, 670, 000

3, 620, 000

2, 970, 000

3, 160, 000

2, 570, 000

2, 120, 000

1,580,000

1, 570, 000

1, 990, 000

2, 870, 000

4, 150, 000

3, 260, 000

2, 760, 000

2, 150, 000

2, 050, 000

94, 760, 000

June

Mean 

discharge 

(secondfeet)

78, 700

75,100

72,200

70, 700

69,000

67,400

66,800

67,700

72,300

81,700

83,500

77,700

70,200

63,-000

58,600

56,700

56,300

56,000

57,200

59, 800

64,700

72,400

75,100

74,700

74,000

73,700

74,900

70, 100

66,100

60,600

Suspended sediment

Mean 

percent

0.78

.64

.70

.62

.63

.62

.68

.61

.72

1.06

1.32

1.46

.88

.93

.72

.60

.62

.48

.60

.56

.62

1.65

.70

.58

.73

.67

.62

.72

.58

.55

Tons per 

day

1, 660, 000

1,300,000

1, 360, 000

1, 180, 000

1, 170, 000

1, 130, 000

1, 230, 000

1, 120, 000

1, 410, 000

2, 340, 000

2, 980, 000

3, 060, 000

1, 670, 000

1, 580, 000

1, 140, 000

919, 000

942,000

726,000

927, 000

904,000

1,080,000

1, 270, 000

1, 420, 000

1,170,000

1,460,000

1, 330, 000

1,250,000

1, 360, 000

1,040,000

900,000

41, 020, 000

1941

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...

July

56,200

50,400

45,700

42,600

40,200

37,800

36,400

36,100

34,500

32,200

30,100

29,400

28,400

27,900

26,800

25,700

24,100

23,000

22,400

21,600

20,700

21,900

21, 300

22,300

20,400

20,300

19,100

18,600

17,200

15,600

14,800

Monthly lot

10.50

.38

.36

.35

».35

.33

.27

.33

».30

.24

.25

.24

.22

.23

.20

1.20

.22

.21

1.20

1.20

.16

.28

1.28

.27

1.30

.49

.53

.68

1.68

.67

.36

id (tons)-

759,000

517,000

444,000

403,000

380,000

337,000

265,000

322,000

279,000

209,000

203,000

190,000

169,000

173, 000

145,000

139,000

143,000

130,000

121, 000

117,000

89,400

166,000

161, 000

163,000

165, 000

269,000

273, 000

341,000

316,000

282,000

144,000

7,814,000

August

14,200

13,400

12,400

11,500

10,700

10,100

10,000

9,380

9,780

9,610

11,400

23,500

23,500

18,900

17,300

17,800

19, 100

18,400

17,100

17,500

18,100

16,900

14,900

13,400

13, 700

12,600

11,500

10,500

9,450

8,890

8,430

0.30

.26

.14

.11

1.10

.08

.07

.07

,12

.40

il.OO

2.89

'2.80

2.84

12.00

1.39

5.44

3.41

13.00

2.07

1.84

1.69

1.20

1.08

.99

U.OO

U.OO

1.09

.98

.82

.69

115, 000

94, 100

46,900

34,200

28,900

21,800

18,900

17, 700

31,700

104,000

308,000

1, 830, 000

1, 780, 000

1, 450, 000

934,000

668,000

2, 810, 000

1, 690, 000

1, 380, 000

978,000

899,000

771,000

483,000

391,000

366,000

340,000

310, 000

309,000

250,000

197, 000

157,000

18,810,000

September

7,740

7,140

6,730

6,790

7,520

7,650

7,180

«,790

6,610

6,120

5,760

5,540

5,350

7,150

8,460

10,100

11,000

12,400

12,700

11,600

12,400

10,700

12,200

13,600

23,300

25,700

19,300

16,800

16,500

21,200

0.71

.86

.84

.60

.39

1.30

1.30

.22

.22

.36

.35

.28

.39

1.98

2.02

1.68

1.93

1.65

3.03

12.50

12.00

1.40

1.35

1.80

2.09

12.50

2.71

1.58

1.45

1.88

148,000

166,000

153,000

110,000

79,200

62,000

58,200

40,300

39,300

59,500

54,400

41,900

56,300

382,000

461,000

458, 000

573,000

552,000

1, 040, 000

783,000

670,000

404,000

445,000

661,000

1, 320, 000

1, 740, 000

1, 410, 000

717,000

646,000

1, 080, 000

14, 410, 000

i Estimated.
54 SEDIMENT IN COLORADO RIVER, 192 5-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 30, 1936

Sampling points: Except as otherwise indicated, samples were taken at points A to D at distances of 120 

180, 240, and 300 feet, respectively, from zero mark on cable at north bank; the letter x denotes sampling 

points A to D at distances of 100,160, 280, and 360 feet from zero mark on cable; y denotes sampling points 

at 140, 200, 260, and 330 feet from zero mark; z denotes sampling points at 150, 210, 270, and 360 feet from 

zero mark.

Type of sample: I, Integrated; S, surface.

Date

19S5 

Apr. 1.... - --....

Apr. 2. _____ . ...

Apr. 3... __ . __ __

Apr. 4..... ___ ....

Apr. 6_ __ --.-.....

Apr. 7..... ......... 

Apr. 8-... ........_

Apr. 9.... ..........

Apr. 10.. ...........

Apr. 11.... __ . ...

Apr. 12.. ........

Time

4

9:15 a.m. ... _ ....

4:30 p. m... ---------

4:30 p. m.-_ _ . .....

10:40 a. m__. ........ 

4:30p. m...-. .......

4:35 p. m_. .... ------

7:05p. m... ...... .

4:20 p. m_ _ ..... ...

9:45 a. m. ____.___._

3:15 p. m

9:40 a. m_. _ . __ .

4:35 p. m__ _ .__ _ .

7:00 a. m. ..........

9:35 a. m_ _ .... _ .

2:55 p. m _ ..... ....

5:00 p. m.. ...... ....

9:30 a. m._ __ . ....

6:55 a. m .._.__._...

10:15 a. m. __ ....

7:15 a. m__ __ . ...

Gage 

height 

(feet)

4.87

5.15 

5.42

5.71 

5.75 

5.75

6.12 

5.91

6.00 

5.89

5.80 

5.75

6.16 

6.04 

6.04

6.74 

6.74 

6.72

7.25 

7.25 

7.10 

7.10

7.22 

7.04

7.37

7.33 

7.38

7.48 

7.50

9.47 

9.47

8.30

8.32 

8.59

8.59

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.88

1.03 

1.19

1.25 

1.29 

.99

1.26 

1.26

1.29 

1.26

1.43 

1.30 

1.12 

1.42 

 1.33 

1.13

1.43 

1.34 

1.20

1.53 

1.18 

1.40

1.48 

1.29 

1.42 

1.29

1.41 

1.63 

1.38 

1.30 

1.39 

1.29

1.51 

1.22 

1.30 

1.46

1.72 

2.01 

1.72

2.57 

2.50 

2.12 

3.55 

3.51 

3.15

2.20 

2.00 

1.99 

1.91 

1.67 

1.94 

1.54

B

0.90

.93 

1.11

1.24 

1.27 

.95

1.35 

1.16 

.87 

1.28 

1.34 

.95

1.18 

1.36 

1.05 

1.24 

1.24 

1.08

1.34 

1.36 

1.20

1.40 

1.02 

1.38

1.40 

1.17 

1.40 

.96

1.46 

1.46 

1.13 

1.29 

1.41 

.96

1.52 

.80 

1.21 

1.51 

l.OQ 

1.66 

1.85 

1.45

2.99 

2.72 

1.11 

3.47 

3.39 

2.39

2. T° 

1.49 

2.20 

1.95 

1.16 

2.01 

1.16

O

0.98

.93 

1.21

1.32 

1.22 

.88

1.32 

1.20 

.86 

1.16 

1.35 

.87

1.40 

1.36 

.94 

1.33 

1.26 

.94

1.42 

1.35 

1.00

1.38 

.89 

1.44

1.60 

1.18 

1.57 

.84

1.57 

1.50 

.91 

1.45 

1.24 

,91

1.56 

.78 

1.44 

1.46 

.95 

1.82 

1.96 

1.38

2.78 

2.87 

.88 

3.78 

4.16 

2.37

2.61 

1.42 

2.78 

2.27 

1.21 

1.90 

1.21

D

0.96

.92 

1.14

1.22 

1.25 

.85

1.23 

.99 

.83 

1.32 

1.00 

.93

1.23 

1.44 

.93 

1.26 

1.24 

M

1.32 

1.48 

.98

1.36 

.84 

1.28

1.52 

1.22 

1.46 

.99

1.57 

1.49 

1.28 

1.29 

1.29 

1.26

1.43 

.82 

1.42 

1.39 

1.00 

1.79 

2.07 

1.29

2.54 

2.24 

1.02 

4.43 

3.82 

2.41

2.18 

1.54 

1.96 

2.20 

1.13 

1.86 

1.14

Type of 

sample

I

I 

I

I 

I

S

I

Iz 

Sz 

I 

Iz

Sz

I

I 

8 

I 

I

S

I 

I

8

r 

s i

i

s I

s

I

Ix

Sx 

I 

Ix

Sx

I

S 

I 

I

S

I

I 

s

I

ly

Sy

iySy

i

s i i 

s I 

s
QUANTITIES OF SUSPENDED SEDIMENT 55

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado Riven at gaging station near Grand Canyon, Ayiz., Apr. 1, 1935, 

to Sept. SO, 19S6 Continued

Date

1935 

Apr. 13.. 

Apr. 14 - 

Apr. 15. 

Apr. 16 - 

Apr. 17 

Apr. 18 

Apr. 19 

Apr. 20 

Apr. 21 _____ ...

Apr. 22........ .. 

Apr. 23 

Apr. 24... ....

Apr. 25 . ...

Time

10:15 a. m-_- ...-. .

9:15 a. m__ _ ....

7:15 a. m.. ------- ... 

10:45 a. m-.-_- __ _

9:20 a.m. ______

6:45 a. m... ---------

4:10 p. m ______ _

9:00 a.m.-.--- ......

9:20 a. m_ -----

10:40 a. m. _____ _

Gage 

height 

(feet)

7.96 

7.73

6.99 

6.91

6.87 

6.70

6.30

6.45 

6.46

6.43 

6.47

6.23 

6.38

6.70 

6.90

7.38

7.39 

7.43

7.59 

7.72

7.94 

8.19

8.28 

8.30 

8.49

8.80

8.37

8.39 

8.43

8.43 

8.46

8.04 

8.24 

8.11

Suspended sediment at sampling" points 

indicated (percent by weight)

A

1.57 

1.42

1.24 

1.19

1.15 

1.12 

1.04 

1.21 

1.19 

1.11

0.96 

.82 

.98 

.92 

.78 

.89 

.86 

.71

.75 

.85

.77

.78 

.77 

.51 

.82 

.84 

.68

1.07 

.96 

.97 

1.02 

.95 

1.07 

1.33 

1.09

1.23 

1.56

1.45 

1.25 

1.24

1.30 

1.51 

1.30 

1.28 

1.40 

.99

1. 14

.98 

1.32 

1.27 

1.18 

1.29 

1.24 

1.09

1.23 

1.03 

1.14

1.05 

1.15 

.84

B

1.68 

1.50

1.50 

1.39

1.15 

1.11 

.87 

1.08 

1.04 

.91

0.84 

.57 

1.01 

1.01 

.64 

.90 

.92 

.57

.83 

.93

.58

.88 

.78 

.49 

1.05 

.95 

.55

1.21 

.66 

.96 

1.10 

.90 

1.20 

1.35 

.67

1.33 

1.64

1.48 

1.17 

1.3ff

1.40 

1.36

.77 

1.46 

1.47 

1.01

1.23 

.87 

1.19 

1.22 

.72 

1.20 

1.06 

.84

1.22 

.85 

1.13

1.15 

1.10

.78

C

1.69 

1.78

1.47 

1.37

1.12 

1.00 

.87 

1.23 

1.19 

.81

0.94 

.63 

.89 

.99 

.64 

.98 

.93 

.55

.91

.88 

.59

.92 

.76 

.54 

.82 

1.17 

.45

1.24 

.73 

1.09 

1.09 

.74 

1.25 

1.37 

.75

1.28 

2.05

1.46 

1.10 

1.35

1.45 

1.22

.78 

1.58 

1.50 

.79

1.14 

.63 

1.28 

1.31 

.81 

1.41 

1.36 

.68

1.30

.78 

1.29

1.20 

1.18 

.65

D

1.48 

1.42

1.20 

1.08

1.03

1.08

0.78 

.71 

.79 

.80 

.73 

.77 

.75 

.72

.69 

.64 

.68

.67

.56 

.65

.65

1.00 

.79 

.95 

.86 

.77 

.91 

1.10 

.73

1.21 

1.34

1.48 

.92 

1.17

1.20 

1.34 

1.35 

1.33 

1.26 

1.17

1. 15 

.90 

1.12 

1.13 

1.09 

1.23 

1.25 

.81

1.15 

.72 

1.28

.97

.88 

.72

Type of 

sample

I 

I

I 

I

I 

Ix

Sx 

I 

Ix

Sx

I

S 

I 

I

S

I I

s

I I

s

I lySiy

i y

I 

s i i

s I I

s

I I

I

s I

I

Ix

Sx 

I 

Ix

Sx

I 

S 

I 

I

S

I

I

s

I

s I

I

S y

Sy
56 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1986, 

to Sept. SO, 1936 Continued

Date

19SB 

Apr. 25, ... ...

Apr. 26 

Apr. 27 ..........

Apr. 28. 

Apr. 29 ------- 

Apr. 30 ------

Mayl---- -- 

May 2.. .. .. 

May 5_--------- ...

Time

4:18 p. m....... .....

7:00 a. m. ------ _ .

9:10 a. m... --------

9:10 a. m.-- -.-.

8:55 a. m. ---------

9:22 a. m- --------

10:10 a. m- ........

9:10 a. m.- __ .. ....

2:35 p. m ____ -

4:40 p. m __ . __ ...

8:45 a. m._ ..........

12:00n. .. ...........

10:10 a. m.- _ ..

Gage 

height 

(feet)

8.14

8.21

8.29 

8.30

8.41 

 8.50 

8.50

8.95 

9.15

9.65 

9. 46 :

8.88 

8.60

8.25 

8.21

8.22 

8.18

8.19 

8.18 

8.33

8.42

8.70

8.84 

8.96

8.97

9.09 

9.10

9.37 

9.56

9.80 

9.95 

9.29

9.11

Suspended sediment at sampling points 

indicated (percent by weight)

A

1.08 

1.05 

.96

1.06 

.90 

.95 

.93 

.95 

1.06 

1.17 

.90

1.02 

1.33

1.24 

1.33 

1.10

.99 

1.22 

1.03 

1.00 

1.16 

1.00

.90 

.92 

.71 

.84 

.93 

.81

.91 

.73

.78

.86 

.86 

.67 

1.01 

' .93 

.71

.89 

.56 

.92 

1.01 

.79 

1.06 

.78 

.88 

1.15 

.99

1.15 

1.06

1.30 

1.03 

1.15

1.09 

1.05 

.90 

1.13 

1.26 

1.10

B

1.13 

1.19 

.70

.98 

.66 

1.10 

1.14 

.62 

1.13 

1.16 

.62

1.11 

1.52

1.31 

1.32 

.98

1.20 

1.30 

.79 

.97 

1.09 

.76

.98 

.90 

.44 

.98 

.92 

.65

.79 

.41 

.40

.93 

.66 

.44 

1.04 

1.00 

.44

1.01 

.46 

1.01

1.18 

.67 

1.11 

.92 

.49

1.03 

1.07

1.49 

.70 

1.19

.90 

.81 

.62 

1.12 

1.13 

.88

C

1.13 

1.19 

.74

1.21 

.60 

1.09 

1.18 

.64 

1.36 

1.18 

.52

1.12 

1.48

1.53 

1.80 

.72

1.25 

.92 

.60 

1.24 

.98 

.62

1.01

.85 

.54 

.96 

.94 

.44

1.25 

.46 

.85

.98 

.95 

.40 

1.13 

.99 

.40

1.02 

.42 

1.23

1.15 

.55 

1.20 

1.26 

.56

1.53 

1.62

1.54 

.71 

1.35

.88 

.83 

.43 

1.11 

1.13 

.61

D

1.04 

1.08 

.74

.85 

.64 

.81 

.78 

.53 

.92 

1.17 

.52

1.28 

1.25

1.30 

1.44 

.66

.94 

1.12 

1.05 

.90 

.92 

.94

.82 

.82 

.48 

.90 

.95 

.51

.73 

.40 

.70

.77 

.72 

.45 

.84 

.72 

.41

.84 

.44 

.94

.99 

.42 

1.05 

1.05 

.49

1.04 

1.31

1.15 

.53 

1.04

.85 

.96 

.88 

1.12 

1.17 

1.01

Type of 

sample

I

lySy

I

S

I I

s I I

s

I I

I I

s

I

Ix

Sx 

I 

Ix

Sx

I

I 

S 

I 

I

S

I

s I

I ly

Sy

ly

Sy

I

S

I I

s IS '

I I

s

I I

I

s I

I

Ix

Sx 

I 

Ix

Sx
QUANTITIES OF SUSPENDED SEDIMENl 57

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Anz., Apr. 1, 1935, 

to Sept. 30, 1936 Continued

Date

1935

May 8.. ------ 

May9-.-- ----

May 10.--. 

May 11.---- 

May 12..-- .

May 13-.-- 

May 14-. 

May 15-.-- 

May 16... 

May 17.---.. .

Mayl8._... .......

May 19. _____

May20_._ ..

Time

12:15 p. m_ ........

12:30 p. m._ .... ____ _

9:30 a. m____ __ . ... ..

4:48 p. m_. . ____ ..

9:00 a. m_.__ __ ....

4:10 p. m_ __ ......

9:15 a. m____ _

7:03a. m.._ .........

4:30 p. m... .........

7:20 p. m __ . _

9:05 a. m__ .......... 

4:20 p. m. .......

7:05 a. m... .. _ . ...

4:05 p. m.. .. ........

4:40 p. m .........

9:20 a. m-_ __ . ....

9:22 a. m. ...........

4:17 p.m.... ........

Gage 

height 

.(feet)

8.79

8.70 

8.78

, 8.67

8.24 

8.17

8.13 

8.12

7.97

7.94 

7.99

7.93 

7.91

7.78 

7.89

7.90 

8.01

8/35 

8.55

9.02

9.17 

9.36 

9.41

9.91 

10.15

10.70 

10.88

11.86 

11.90 

11.95

12.03 

11.70

11.55 

11.66 

11.70

11.92

Suspended sediment at sampling points 

indicated (percent by weight)

A .

0.98 

.86 

.95 

.95 

.78 

.94

1.01 

1.04 

.94

.93

.88 

.72 

.86 

.85 

.70

.68 

.66 

.89 

.71 

.57 

.72 

.71 

.57

.71 

.64

.57 

.66 

.56

1.41 

.87

.75 

.63 

.72 

.73 

.88 

.63

.90 

1.02 

.95

1.14 

1.29 

.89 

.90 

1.06 

.74

1.31 

1.19 

1.65 

1.28 

1.15

1.53 

1.34

1.39 

1.16 

.92

1.38 

1.49 

1.22 

1.38 

1.45 

1.09

B

0.89 

.67 

1.04 

.84 

.65 

.95

1.17 

.97

.97 

.98 

.54 

.80 

.91 

.53

.76 

.45 

.68 

.71 

.48 

.77 

.70 ^.47

.71 

.62

.59 

.75 

.34

.67 

.90

.78 

.44 

.82 

.72 

.94 

.49

.91 

.85 

.62

1.22

L28 

1.23

.77

1.60 

1.12 

1.40 

.95 

1.34

1.50 

1.32

1.23 

.97 

1.49

1.53 

1.22 

.95 

1.09 

1.16 

1.05

C

1.14 

.63 

1.09 

.98 

.60 

1.06

1.19 

1.06 

.70

.97 

.97 

.59 

.86 

.85 

.53

.77 

.46 

.83 

.77 

.40 

.78 

.80 

..45

.76 

.64

.73 

.87 

.32

.79 

.93

.87 

.32 

.88 

.87 

.91 

.38

.90 

1.25 

.60

1.04 

1.10 

.53 

1.26 

1.28 

.68

1.60 

1.14 

1.72 

.88 

1.46

1.77 

1.70

1.54 

.90 

1.34

1.68 

1.26 

.74 

2.20 

1.32 

.78

D

0.93 

.58 

.99 

1.05 

.69 

1.17

1.02 

1.01 

.65

.93 

.73 

.58 

.75 

.75 

.54

.66 

.51 

.63 

.63 

.42 

.68 

.70 

.43

.81 

.59

.55 

.67 

.27

.63 

.68

.68 

.32 

.71 

.71 

.87 

.34

.82 

1.22 

.50

1.08 

1.11 

.57 

1.10 

.95 

.56

1.44 

.66 

1.48 

.75 

1.30

1.60 

1.42

2.17 

.63 

1.56

1.14 

1.25 

.82 

1.48 

.98 

.62

Type of 

sample

I

S 

I 

I

S

I

I I

s

I

ly

Sy

ly

Sy

I

S 

I 

I

S

I I

s

I I

I I

s

I I

I

s I I I

s

I I

s

 I lySy

iySy

I

S

I

s i :

i i

i'

s i

i

Ix

Sx 

I 

Ix

Sx
58 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1985, 

to Sept. SO, 1986 Continued

Date

1935

TVfft T7-"91

May 22 __ ........

May 23 _ ........

May 24.. ..... 

May 25...-.. 

May 26-. .... 

May 27..- ... 

May 28-. ... .... 

May29i- .. ..

Time

A*AQ -r\ m

7:00 a.m..-.. __ ...

4:13 p. m... ........ .

9:50 a. m... .____.___

6:50 a.m. ...........

8:40 a.m.-. .........

12:15 p. m_._. .......

4:40 p. m _____ ... 

7:30 p. m._ ..........

9:35 a. m... .........

4:25 p. m ............

4:00 1). m ............

Gage 

height 

(feet)

12.15

12.15 

12.25

12.23

12.47 

12.53

13.18 

13.88

14.04

13.92 

13.61 

13.41

12.70 

12.49

12.30 

12. 38 

12.71

12.96

13.45

13.70 

14.00

14.17

14.95 

15.38

15.90 

15.97

16.14

16.78

17.12 

17.15 

17.30

17.65 

17.72

17.76 

17.85

Suspended sediment at sampling points 

indicated (percent by weight)

A

1.25 

1.17 

1.05 

1.11 

.88 

1.30

1.17 

1.26 

1.04

1.55 

1.26 

1.08 

1.58 

1.29 

1.18

1.45 

1.24 

1.20 

1.28 

1.44 

1.24

.1.50 

1.33

1.04

.93

.99 

' 1.01 

.88 

1.15 

1.18 

.79

1.00 

1.10 

1.12 

.84 

.84 

1.13

1.25 

1.13 

1.07

1.40 

1.15 

1.30 

1.06 

1.28 

1.23 

1.26

1.54 

1.38 

1.20 

1.29 

1.92 

1.73

1.89 

1.63

1.76 

1.94

B

1.32 

1.03 

1.17 

1.18 

.85 

1.33

1.17 

1.05 

.91

1.28 

1.25 

.97 

1.20 

1.18 

.93

1.52 

1.12 

1.65 

1.44 

1.22 

1.06

1.39 

1.42

.96 

.76 

.92

.92 

.96 

.78 

.78 

1.10 

.83

1.09

1.13 

.98 

.75 

.89

1.04 

2.23 

.86

1.35 

1.13 

1.56 

.92 

1.38 

1.32 

1.08

1.82 

.82 

1.45 

1.21 

1.58 

1.17

3.78 

1.44

1.34 

1.67

C

1.57 

1.10 

1.19 

1.26 

.84 

1.32

1.29 

1.24 

.83

1.34 

1.28 

1.00 

2.39 

1.51 

.98

1.17 

.90 

1.80 

1.34 

1.27 

.99

1.54 

1.78

1.23

.76 

1.25

.86 

1.02 

.64 

1.05 

.96

1.00 

1.43 

1.31 

.50 

.76 

1.04

1.18 

1.31 

1.06'

1.67 

1.69 

1.28 

.83 

1.14 

1.40 

1.00

1.75 

.64 

2.43 

1.46 

1.60 

1.23

1.56 

1.63

1.96 

1.73

D

1.36 

.87 

1.26 

1.07 

.57 

1.36

1.28 

1.35

.78

1.68 

1.46 

.68 

1.52 

1.37 

.67

1.74 

.97 

1.90 

1.89 

1.37 

.82

1.46 

1.40

1.32

.70 

1.03

1.05 

1.15

.77 

1.05 

.92 

.71

1.25 

.99 

1.14 

.59 

.64 

1.13

1.19 

1.66 

1.00

1.39 

1.39 

1.53 

.74 

1.25 

1.48 

.63

1.73 

1.00 

1.47 

1.18 

2.08 

2.49

1.91 

1.76

2.34 

2.51

Type of 

sample

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S 

I 

I

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I

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ly

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I

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I 

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I

S

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I 

Ix Sx

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QUANTITIES OF SUSPENDED SEDIMENT 59

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1985, 

to Sept. SO, 1936 Continued

Date

1935

June 10 _______

June 11 _ .. __

June 12 _______ 

June 13 _ . ____

June 15 _______

Time

»

4:40 p. m ............

9:05 a. m ............

4:30 p. m __ . __ __

10:15 a. m.-_ ...... .

7:50 p. m. ...... ..

12:00 n. .............

7:00 a. m. ...........

4:25 p. m ............

3:50 p. m.-_______.__

8:50 a.m... .........

9:20 a. m. __ . __ .

7:15 a. m...... ...... 

12:45 p. m ...........

8:50 a.m.. _ .......

8:50 a. m. ...........

1:50 p.m... .........

1:20 p. m ............

7:25 p. m ______

8:55 a. m. ...........

4:25 n. m _______

Gage 

height 

(feet)

17.82 

17.85

17.90 

17.80

17.30 

17.15

17.20 

17.18

17.34 

17.44

17. 57 

17. 66

18.12 

18.30

18.96 

19.20

20.00 

20.10

20.20

20.75 

20.85

20.90 

21.00

21.53 

21.70

22.44 

22.58

22.80

23.43 

23.75

23.65 

23.82

24.15 

24.33

Suspended sediment at sampling points 

indicated (percent by weight)

A

1.80 

1.17 

1.16 

1.17

1.62 

1.16 

1.25 

1.11

1.28 

1.16

1.35 

1.20 

.90 

1.15

.88 

.64

1.16 

.82 

1.07 

.86 

1.19 

.99 

.86

1.08 

1.20

1.26 

1.11 

.70

1.07 1.19- 

.85 

1.50 

1.14 

.98

1.26 

.85 

1.97 

.90 

1.19 

1.45 

.99

1.32 

1.39 

1.09

1.21 

1.20 

1.05 

1.15 

1.04 

.94

1.36 

1.00 

1.26 

1.16 

1.33 

1.01 

1.32

1.05 

1.08

B

1.37 

.91 

.96 

1.17

1.66 

.90 

1.09 

.97

1.28 

.94

.99 

1.25 

.75 

1.04 

1.07 

.67

.71 

.77 

.86 

.65 

1.16 

1.29 

.70

1.02 

.93

1.17 

1.10 

.68

.81 

1.09 

.84 

1.76 

1.32 

.86

1.11 

.85 

2.82 

1.21 

1.16 

1.05 

.76

1.10 

1.18 

.82

.93 

.93 

.83 

1.16 

.96 

1.11

1.32 

.99 

1.05 

.67 

1.11 

1.24 

.91

1.04 

.83

C

1.42 

1.05 

2.63 

1.22

1.41 

.88 

1.74 

.90

1.49 

.99

1.54 

1.04 

.82 

.79 

1.04 

.77

.92 

.72 

.99 

.73 

1.19 

1.17 

.80

1.00 

1.04

1.22 

1.50 

.86

1.69 

1.37 

.89 

1.50 

1.47 

.86

1.23 

.88 

3.15 

.81 

1.39 

.96 

_ .91

1.13

1.47 

.80

1.09 

1.40 

.88 

.89 

1.18 

.95

1.09 

.87 

1.24 

.88 

1.20 

1.20 

.82

1.03 

1.05

D

1.72 

1.21

.69

1.33

.84 

1.54 

.78

2.04 

1.31

.98 

1.40 

1.08 

1.17 

.97 

.65

1.13

.77 

1.27 

.75 

1.13 

1.11 

.80

1.34 

1.21

1.49 

1.38 

.88

2.53 

1.28 

.86 

1.57 

1.13 

.74

1.60 

1.22 

1.23 

1.02 

1.39 

1.35 

.97

1.21 

1.25 

.95

1.17 

1.28 

.94 

1.42 

1.26 

.92

1.36 

1.19 

1.20 

.92 

1.39 

1.24 

.89

1.15 

1.21

Type of 

sample

I

S 

S 

Sx

I

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I

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i y

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I

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I

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I I

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I

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I 

Ix

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725606 47 5
60 SEDIMENT IN COLORADO RIVER, 1925-41

10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 30, 1986 Continued

Date

1935

JllUG 19

Tnna 9,4

Time

4:30 p. m _ . ___ .

6:50 a. m. ...........

12:50 p. m..... ......

4:20 p. m ............

7:25 p. m _ .........

8:25 a. m. ...........

8:50 a. m. _____ .

3:55 p. m... .........

6:50 a. m_ .........

12:05 p.m...........

7:40p.m.... ........

8:40 a. m............

4:50p. m ______ _

8:50 a. m. .........

3:45 p. m ............

8:45 a. m. ...........

4:25 p. m ______ _

6:40 a. m. ...........

3:40p. m ...........

8:45 a. m. ______

4:00 p. m ............

8:40 a. m. ...........

4:25 p. m ______ .

8:55 a. m ______ _

12:30 p. m_. .........

4:10 p. m _____ ...

Gage 

/height 

(feet)

24.55 

24.72

25.30 

25.55

26.20 

26.20

26.30 

26.35

26.75 

26.40

25.30 

24.78

23.90 

23.60

23.60 

23.30

23.27 

23.00

22.79 

22.70

22.87 

22.68

22.36

22.30 

22.06 

21. 90

21.48 

21.07

21.20 

20.93

20.46 

20.18

20.08 

19.92

Suspended sediment at sampling points 

indicated (percent by weight)

A

1.04 

1.02

1.06 

1.02 

.71 

1.13 

.86 

.78

1.12 

.71 

.99 

.65 

1.04 

1.05 

.78

.64 

1.04

.93 

.88 

.55 

.81 

.67 

.51

.74 

.65 

.69 

.45 

.64 

.73 

.60

.65 

.52 

.48

.57- 

.54

.58 

.57 

.39 

.57 

.56 

.46

.60 

.45 

.57 

.54 

.55 

.44

.48 .42' 

.37

.55 

.48 

.31 

.47 

.47 

.34

.40 

.43 

.36 

.44 

.38 

.33

B

0.98 

1.15

.87 

1.00 

.52 

.94 

.96 

.77

.99 

.54 

.83 

.63 

.98 

.81 

.64

.77 

.82

.69 

.76 

.55 

.66 

.69 

.46

.75 

.52 

.75 

 .36 

.64 

.63 

.67

.60 

.50 

.55

.55 

.52

.52 

.52 

.40 

.65 

.63 

.43

.63 

.36 

.53 

.51 

.54 

.43

.52 

.37 

.30

.48 

.46 

.32 

.45 

.44 

.38

.44 

.48 

.27 

.42 

.42 

.28

C

0.91 

1.11

.65 

1.15 

.62 

1.19 

.94 

.72

.97 

.65 

.89 

.64 

.94 

.83 

.60

.73 

.88

.73 

.75 

.47 

.83 

.68 

.47

.64 

.45 

.79 

.46 

.63 

.70 

.50

.55 

.55 

.56

.53 

.56

.52 

.58 

.39 

.52 

.53 

.33

.60 

.39 

.50 

.51 

.55 -.44

.46 

.38 

.36

.40 

.55 

.34 

.43 

.41 

.32

.53 

.49 

.29 

.43 

.46 

.29

D

1.39 

1.11

.96 

1.26 

1.41 

1.17 

1.29 

1.51

1.06 

.96 

1.05 

.75 

1.45 

1.11 

.90

.82 

.87

.96 

1.03 

.65 

.76 

.80 

.57

.89 

.48 

.73 

.52 

.68 .79* 

.60

.53 

.53 

.49

.53 

.50

.55 

.64 

 .67 

.61 

.76 

.77

.63 

.40 

.45 

.58 

.60 

.37

.49 

.44 

.35

.59 

.56 

.37 

.46 

.46 

.37

.42 

.44 

.37 

.45 

.39 

.31

Type of 

sample

I

S

I 

Ix

Sx 

I 

Ix

Sx

I

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I 

S

I I

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I I

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JySy

ly

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I 

S 

I

S

I I

s

I I 

s

I

I

I

Ix

Sx 

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Ix

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QUANTITIES OF SUSPENDED SEDIMENT 61

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon^, Ariz., Apr. 1, 1935, 

to Sept. SO, 1986 Continued

Date

1935

July 1.... ..........

July 2_ .......

Julys.............

July 4..... .........

July 5.-....-. 

July 6.-.... ... 

July?. ........

JulyS 

July 9..... .........

July 10.... .........

July 11.. ...........

Time

4:10 p. m ______

10:35 a. m. .........

4:25 p.m...... __

7:00 p. m ______

9:20 a. m. ..........

3:30p. m... _.._._ ...

9:30 a. ta .........

9:05 a. m._ ....

12:55 p. m.. .... _

4:35 p. m ....

7:25 p. m ......

9:55 a. m._ ..... __ . 

4:00 p. m._ ..........

9:00 a. m.. .........

4:30 p. m. ___ ...

12:05 p.m.... .......

9:00 a. m .......... 

4:10 p. m- -_ 

Gage 

height 

(feet)

19.48 

19.08

18.78 

18.56

18.16 

18.00

17.43

17.38 

17.33

17.23 

17.09

16.80 

16.80

16.32 

16.21

15.76 

15.66

15.74 

15.60

15.35 

15.19

14.86 

14.81

14.50 

14.40

13.98 

13.77

13.72 

13.70

13.31 

13.21

12.93

12.93 

' 12.93

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.40 

.34 

.35

.37 

.39

.35 

.39 

.33 

.33 

.37 

.26

.39 

.29 

.36 

.34 

.29 

.33 

.38 

.34

.27 

.42

.32 

.29 

.27 

.22

.30 

.25 

.23 

.26 

.32 

.27

.31 

.28 

.25

.22 

.21

.23 

.22 

.17 

.24 

.23 

.19

.24 

.19 

.24 

.18 

.22 

.24 

.16

.19 

.19

.19 

.20 

.17 

.16 

.15 

.15 

.14

B

0.41 

.35 

.37

.35 

.31

.33 

.34 

.28 

.34 

.32 

.29

.34 

.30 

.35 

.36 

.26 

.36 

.35 

.28

.30 

.36

.28 

.27 

.25 

.24

.28 

.26 

.19 

.28 

.32 

.26

.30 

.30 

.24

.22 

.22

.24 

.22 

.18 

.24 

.21 

.17

.23

.18 

.24 

.20 

.26 

.20 

.16

.19 

.18

.21 

.19 

.17 

.18 

.14 

.15 

.13

C

0.37 

.34 

.28

.33 

.36

.36 

.36 

.28 

.34 

.34 

.24

.32 

.25 

.36 

.33 

.28 

.35 

.37 

.31

.28 

.39

.27 

.28 

.27 

.21

.27 

.22 

.19 

.25 

.34 

.29

.38 

.36 

.28

.25 

.22

.23 

.20 

.17 

.20 

.25 

.28

.24 

.21 

.22 

.18 

.22 

.20 

.17

.21 

.22

.23 

.19 

.14 

.14 

.12 

.14 

.14

D

0.44

.32 

.34

.38 

.35

.37 

.47 

.66 

.34 

.50 

.57

.31 

.32 

.33 

.35 

.27 

.31 

.38 

.30

.27 

.36

.27 

.28 

.26 

.22

.27 

.28 

.19 

.25 

.32 

.25

.38 

.27 

.28

.23 

.23

.19 

.30 

..27 

.25 

.28 

.24

.23 

.16

.24 

.15 

.28 

.20 

.14

.20 

.18

.16 

.20 

.12 

.18 

.14 

.18 

.13

Type of 

sample

I

I

S

I 

I

I 

Ix

Sx 

I 

Ix 

Sx

I

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I 

I

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I 

I

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I I

s

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I I

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Ix

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62 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 19S5t 

to Sept. SO, 1936 Continued

Date

1935 

July 12.... .........

July 13............

July 14.. ...........

July 15 . ......... 

July 16.............

July 17.............

July 18.. ...........

July 19 .........

July 20......... ....

July 21....... ......

July 22.............

July 23........ .-

July 24............

July 25...... .......

July 26. ...... ... 

July 27. ___ .. ....

Time

12:40 p. m ...........

4:20 p. m ............

3:50 p.m...... ......

6:55 a. m. ...........

7:30 p. m._ __ . ....

9:15 a. m ............ 

4:25 p. m ............

6:55 a. m....... _ ..

3:40 p. m ............

11:25 a.m.. .........

4:25 p. m ______ .

9:10 a. m. ...........

9:00 a. m ............

4:00 p. m ............

9:35 a. m. ...........

12:55 p. m _____ .

7:25 p. m ............

9:00 a. m ............

7:10 p. m ............

6:55 a. m. ...........

12:00 noon... ____ .

9:30 a. m ___ . .....

8:35 a. m.... ___ .

12:30 p. m... ___ . 

4:25 p. m. _ . ___ -

7:40 p. m ............

9:00 a. m ______ .

Gage 

height 

(feet)

12.64 

12.55

12.45 

12.59

12.54 

12.22

12.12 

12.09

11.96 

11.88

11.79

11.76 

11.60 

11.62

11.50 

11.49

11.29 

11.04

10.83 

10.64

10.43 

10.50

12.04 

11.23 

10.48

10.05 

9.84 

9.67

10.14 

10.32 

10.19

9.97 

9.78

9.44 

9.46

9.40

9.24 

9.15

8.80 

8.90

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.18 

.16

.18 

.13 

.25 

.18 

.17

.15 

.13 

.16

.17 

.17

.17 

.17 

.12 

.15 

% .17 

.14

.17 

.14 

.12 

.15 

.14 

.12

.13 

.11 

.14

.13 

.12

.15 

.14

.27 

.25 

.36

.33 

.33 

.50

.62 

.67 

.55

.59 

.71 

.52

.35 

.34 

.41

.24 

.23

.25 

.23 

.26 

.30 

.29

.57 

.55 

.55 

.52 

.52 

.52

B

0.20 

.14 

.17 

.14 

.23 

.19 

.19

.17 

.12 

.18

.16 

.17

.15 

.17 

.13 

.16 

.15 

.15

.15 

.12 

.14 

.15 

.13 

.11

.14 

.08 

.11

.14 

.15

.15 

.13

.23 

.21 

.36

.39 

.33 

.48

.62 

.69 

.55

.58 

.70 

.53

.35 

.33 

.31

.23 

.23

.26 

.24 

.28

.28

.56 

.56 

.56 

.52 

.52 

.51

O

0.19 

.16 

.17 

.16 

.21 

.18 

.15

.14 

.12 

.16

.17 

.17

.17 

.18 

.12 

.17 

.17 

.13

.15 

.12 

.17

.16 

 .15 

.11

.14 

.10 

.13

.14 

.10

.13 

.13

.23

.20 

.34

.31 

.31 

.48

.61 

.68 

.57

.58 

.69 

.52

.36 

.'33 

.34

.24 

.23

.25 

.24 

.27 

.29 

.29

.56 

.5b 

.56 

.52 

.52 

.51

D

0.16 

.13

.16 

.16 

.22 

.18 

.13

.14 

.13 

.18

.18 

.14

.15 

.18 

.17 

.15 

.18 

.17

.14 

.11 

.16 

.17 

.12 

.10

.12 

.08 

.13

.13 

.11

.14 

.14

.21

.17 

.36

.42 

.33 

.49

.61 

.68 

.56

.59 

.68 

.52

.37 

.33 

.28

.23 

.22

.25 

.24 

.26 

.25 

.29

.56 

.55 

.54 

.52 

.52 

.51

Type of 

sample

I

S 

I

S

I I

s

I

s I

I I

I

Ix

Sx 

I 

Ix

Sx

I

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I 

I 

I

S

I 

s I

I I

I I

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I I I

I I I

I

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I

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QUANTITIES OF SUSPENDED SEDIMENT 63

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 30, 1936 Continued

Date

19S5 

July 28 .... ... ...

July 29 .. ..... ...

July 30 ... .... 

July 31.. _ ........

Aug. 1..............

Aug. 2_. _____ .

Aug. 3 _ ....... _ . 

Aug. 4.... ___ .... 

Aug. 5. .............

Aug. 6. _____ .

Aug. 7 .. . - 

Aug. 8. -.- 

Aug. 9... ... ..

Aug. 10.-..-. 

Time

9:10 a. m ............

8:55 a. m. ........... 

12:25 p. m ...........

7:25 p. m..__ . 

8:25 a. m. ___ . ...

9:35 a. m. _ .....

7:00 a. m_. _ . __ ..

11:10 a. m __ .......

7:10 p. m_ ...........

8:45 a. m. .......... .

9:00 a. m ............

9:55 a. m ______

6:40 a. m. ...........

9:30 a. m.. ..........

9:30 a. m............

6:30 a.m.. ...... ....

9:20 a.m....... .....

7:00 p. m ___ . .....

8:40 a. m. __ .......

4:45 D. m _____ .

Gage 

height 

(feet)

8.48 

8.53

8.15 

8.00

7.75 

7.62

7.52 

7.53

7.31 

7.12

7.03 

6.83

7.12 

7.12 

7.18 

7.07 

7.07 

7.07

6.79 

6.76

6.47 

6.40

6.55 

7.10

7.39

8.98 

8.35

6.70 

6.71

6.70 

6.52

6.78

6.68 

6.51 

6.54

6.45 

6.13

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.50 

.43

.24 

.25 

.23 

.23 

.22 

.21

.23

.21 

 .21 

.21 

.22 

 .21

.19

.18

.16 

.16 

.16 

.16 

.16 

.16

.19 

.18 

.33 

.30 

.19 

.19

.17 

.17

.18 

.24

.32 

.32

.31 

.41 

.41 

.40

2.33 

^2.31 

1.47 

1.65

1.77 

1.31

1.01

.73 

.75 

.65 

.64 

.63

.53

.47 

.41 

.41 

.41

.60

.48

B

0.51

.42

.24 

.24 

.23 

.22 

.22 

.21

.22

.21 

.20 

.21 

.21 

.20

.20 

.18

.16 

.16 

.15 

.16

.17 

.16

.19 

.19 

.33 

.30 

.20 

.19

.17 

.16

.18 

' .29

.32 

.32 

.31 

.41 

.41 

.40

2.36 

2.32 

1.47 

1.63

1.79 

1.31

.75 

.74 

.75 

.64 

.66 

.64

.51 

.52 

.46 

.41 

.42 

.39

.48 

.23

0

0.50 

.43

.24 

.24 

.23 

.23 

.21 

.21

.22 

.21 

.20 

.21 

.22 

.21

".18 .19 

.17 

.16 

.16 

.17 

.16 

.15

.18 

.18 

.32 

.31 

.20 

.19

.21 

.16

.18 

.29

.32 

.32 

.31 

.41 

,.40 

.41

2.39 

2.34 

1.49 

1.57

1.78 

1.30

.74 

.74 

.75 

.66 

.66 

.64

.52 

.52 

.46 

.42 

.41 

.40

.48 

.60

D

0.49 

.44

.24 

.25 

.24 

.22 

.22 

.22

.22 

.21 

.20

.21 

.21 

.20

.20 

.18

.16 

.16 

.15 

.16 

.16 

.15

.18 

.18 

.32 

.31 

.20 

.19

.17 

.16

.18 

.29

.31 

.25 

.30 

.41 

.40 

.40

2.41 

2.35 

1.51 

1.55

 1.80 

1.32

.76 

.74 

.74 

. .65 

.64 

.62

.51 

.37 

.47 

.41 

.41 

.40

.48 

.48

Type of 

sample

I 

I

I 

Ix 

8x 

I 

Ix 

Sx

I 

I

S 

I 

I 

8

I 

I

I

ly

Sy

ly

Sy

I

3 

I 

I 

I 

8

I 

I

I 

I

I 

Ix

Sx 

I 

Ix

Sx

I

S 

I 

I

I 

I

I

S

ly

iySy

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8

I 

I
64 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 19S5, 

to Sept. 30, 1936 Continued

Date

19S5 

Aug. 11.- 

Aug. 12...- 

Aug. 13. .. __ .

Aug. 14 __ ........

Aug. 15. 

Aug. 16. ....... -

Aug. 17- 

v 

Aug. 18 _ .........

Aug. 20--. 

Aug. 22. 

Aug. 23. 

Aug. 24 

Time

11:45 a.m. ___ . _

3:40 p. m _______

4:30 p. m _______

5:00 p.m.... .........

7:00 a. m ............

3:45 p.m... .........

7:00 p.m.... _ ......

8:40 a. m ______

4:30 p. m ..........

9:00 a. m _____

3:50 p. m ............

10:20 a. m ...........

3:00 p. m ............

7:00 p. m _____ ..

4:30 p. m ............

11:45 a.m. ..........

6:10 p. m ______

9:00 a. m... _____ 

4:50 p. m __ ... 

Gage 

height 

(feet)

6.55 

6.51

6.63 

6.71

6.35

6.11 

5.91 

5.79

5.73 

5.57

5.85 

5.62

5.64

5.66 

6.08 

6.29

6.20 

6.46

5.43 

5.17

5.54

5.77 

5.71 

5.57

5.13 

4.74

5.10 

5.79

5.34 

5.00

4.80

4.80 

5.01 

5.25

5.03 

4.92

Suspended sediment at sampling points 

indicated (percent by weight)

A

].68 

1.78

1.18 

1.18 

1.17 

1.09 

1.08 

1.07

1.03 

1.00 

1.01 

.97

.87 

.88

1.07 

1.18

1.04 

1.07 

1.04 

1.30 

1.28 

1.30

1.08 

1.08 

1.10

.88 

.85 

.85

.77 

.74

1.15 

1.57

.61 

.60

.54 

.48 

.48 

.49

'.42 

' .42 

.43 

.39 

.38 

.39

.44 

.46

.53 

.56 

.55 

.54 

.54 

.52

.47 

.48 

.44 

.43 

.44 

.43

.51 

.50

B

1.65 

1.80

1.18 

1.17 

1.19 

1.08 

1.07 

1.07

1.02

1.01 

.97 

.86 

.88

1.07 

1.06

1.02 

1.02 

1.03 

1.31 

1.31 

1.31

1.06 

1.08 

1.10 

.88 

.84 

.85

.76

.74

1.13 

1.56

.61 

.60 

.54 

.48 

.49 

.50

.42 

.41 

.42 

.38 

.37 

.38

.42 

.46

.54 

.55 

.55 

.54 

.54 

.52

.48 

.53 

.44 

.69 

.44 

.42

.51 

.50

O

1.62 

1.81

1.19 

1.16 

1.19 

1.09 

1.07 

1.07

1.01 

1.00 

1.03 

.96

.88 

.88

1.06 

1.20

1.01 

1.00 

1.01 

1.31 

1.30 

L31

1.07 

1.07 

1.10 

.88 

.84 

.84

.77 

.74

1.14 

1.56

.62 

.60 

.54 

.48 

.48 

.49

.43 

.40 

.42 

.38 

.37 

.38

.42 

.45

.55 

.55 

.55 

.54 

.54 

.52

.48 

.57 

.44 

.44 

.43 

.42

.50 

.50

D

1.63 

1.81

1.17 

1.19 

1.19 

1.09 

1.08 

1.07

1.02 

.99 

1.02 

.96 

.86 

.89

 1.05 

1.19

1.00 

.99 

.99 

1.31 

1.27 

1.31

1.08 

1.06 

1.09

.88 

.85 

.85

.78 

.73

1.15 

1.56

.62 

.61 

.53 

.47 

.47 

.48

.42 

.42 

.42 

.38 

.38 

.39

.36

.45

.54 

.55 

.55 

.53 

.52 

.53

.47 

.48 

.44 

.44 

.44 

.42

.50 

.49

Type of 

sample

I 

I

I

Ix 

Sx 

Ix 

Sx 

I~

I

S 

I 

I

S

I

I I

ly

f

Sy 

ly

s i i i 

s I

I I

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s I I 

s I

I

s

IxI

Sx 

Ix

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I I
QUANTITIES OF SUSPENDED SEDIMENT 65

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1985, 

to Sept. 80, 1936 Continued

Date

19S5 

Aug. 25 ___ ......

Aug. 26. ______ . 

Aug. 27 _ .........

Aug. 28...... __ ..

Aug. 29 _ . __ ....

Aug.30............

Aug. 31............ 

Sept. 1 _ ..........

Sept. 2 _____ ... 

Sept. 3... ..........

Sept. 4 ______ 

Sept. 5.... .........

Sept. 6 ______ 

Sept. 7 .............

Time

9:20 a. m ............ 

4:10 p. m ............

8:45 a. m.. ._ .....

12:10 p. m ___ .....

4:30 p. m ............

7:30 p. m __ . _ ...

6:30 a. m ............

12:15 p. m _ ..... ...

4:30 p. m ............

7:10 p. m ............

8:45 a. m. ...........

4:40 p. m ............

8:45 a. m. ...........

4:40 p, m ............

6:40 a. m.. .......... 

11:00 a. m. ..........

3:30 p. m ............

8:45 a. m. ........... 

4:30 p. m ............

9:30 a. m. ...........

5:00 p. m ............

8:40 a. m. ...........

4:45 p. m _______

6:45 a. m. ...........

8:45 a. m ............

9:30 a.m.. __ . _ . 

4:40 p. m ............

6:40 a. m- ........... 

11:50 a.m. ..........

8:40 a. m.__-___.___. 

4:20 p. m.. ..........

Gage 

height 

(feet)

4.73 

4.84

7.42

6.90 

6.13

5.72 

5.33

5.30 

5.50 

5.61

7.01 

6.72

6.49 

6.40

6.11

5.92 

5.78 

5.65

5.39 

5.28

5.94 

6.07

6.63 

6.96

7.38

7.01 

7.52 

7.81

8.25 

7.44

6.62 

6.40

5.82

5.60 

5.43 

5.41

5.12 

4.83

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.53 

.52

2.38 

2.40 

2.92 

6.86 

6.96 

6.98

2.96 

2.92 

2.50 

2.31 

2.42 

2.38

2.88 

2.59

2.01 

2.00 

1.98 

1.71 

1.72 

1.68

1.68 

1.67 

1.58 

1.65 

1.89 

1.85

2.14 

2.15

1.45 

1.39

1.68 

1.64 

1.63 

1.99 

1.97 

1.98

2.66 

2.64 

2.61 

2.87 

3.02 

2.99

4.83 

5.21

2.87 

2.78 

2.74 

2.21 

2.20 

2.17

2.04 

2.00 

1.89 

1.86 

1.89 

1.64

1.95 

2.08

B

0.54 

.52

2.35 

2.32 

2.94 

6.78 

6.77 

7.01

3.01 

2.98 

2.53 

2.32 

2.41 

2.41

2.91 

2.56

2.02 

2.04 

1.98 

1.71 

1.74 

1.68

1.69 

1.65 

1.58 

1.64 

1.86 

1.85

2.12 

2.15

1.46 

1.40

1.68 

1.66 

1.63 

2.01 

2.00 

1.99

2.67 

2.63 

2.62 

2.93 

3.02 

2.93

4.79 

5.27

2.90 

2.80 

2.78 

2.23 

2.23 

2.19

2.05 

2.00 

1.88 

2.08 

1.90 

1.83

1.97 

2.08

C

0.53 

.52

2.24 

2.32 

2.92 

6.69 

6.63 

7.07

3.03 

2.94 

2.52 

2.30 

2.39 

2.37

2.92 

2.57

1.99 

2.04 

1.98 

1.72 

1.74 

1.70

1.68 

1.67 

1.58 

1.65 

1.85 

1.83

2.14 

2.16

1.46 

1.40

1.66 

1.63 

1.62 

2.03 

2.01 

2.01

2.65 

2.56 

2.67 

2.92 

3.00 

2.95

4.71 

5.30

2.83 

2.83 

2.81 

2.23 

2.25 

2.17

2.03 

2.00 

1.89 

1.86 

1.88 

1.86

1.93

2. (15

D

0.53 

.52

2.15 

2.16 

2.89 

6.70 

6.64 

7.10

3.03 

3.01 

2.55 

2.30 

2.37 

2.35

2.93 

2.55

2.03 

2.01 

1.96 

1.75 

1.73 

1.70

1.69 

1.64 

1.58 

1.64 

1.83 

1.78

2.13 

2.15

1.46 

 1.41

1.65 

1.62 

1.63 

2.03 

2.02 

2.00

2.62 

2.59 

2.69 

2.91 

3.00 

2.94

4.76 

5.30

2.84 

2.83 

2.76 

2.24 

2.23 

2.15

2.02 

1.98 

1.94 

1.86 

1.86 

1.84

1.96 

2.05

Type of 

sample

I 

I

I 

Ix 

I 

I 

Ix 

I

I

S 

I 

I 

I

S

I I

I ly

V iy

Sy

I

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I
66 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr, 1, 1935, 

to Sept. SO, 1936 Continued

Date

1935

Sept. 9. _____ .. 

Sept. 10...... _ ... 

Sept. 11. .... ... .

Sept. 12-... ....

Sept. 14............

Sept. 15 ... __ .

Sept. 16 . ___ .

Sept. 17. .. ....

Sept. 18... ......... 

Sept. 19 .........

Sept. 20 .........

Sept. 21 __ . _ . ...

Time

8:50 a. m. ........... 

4:20 p. m ............

6:40 a. m ............ 

11:50 a. m. ..........

4:20 p. m ____________

7:30 p. m ............

4:50 p. m ............

9:30 a. m. ...........

11:30 a. m_. ........

7:40 p. m ............

8:30 a. m.--._ ___ .

4:30 p.m. _ ........

9:10 a. m ............

4:25 p. m ............

3:50 a. m... .... __ . 

11:50 a.m.... .......

8:40 a. m. ___ . 

4:20 p. m ............

8:50 a. m ............

6:45 a. m. ...........

11:20 a. m. ..........

4:30 p. m ............

8:30 a. m... .........

4:30o. m _ . ........

Gage 

height 

(feet)

4.60 

4.41

4.26 

4.13

4.05

4.00 

4.00 

4.08

4.17 

3.92

3.84 

3.70

3.59

3.74 

4.02 

4.09

4.25 

4.22

4.17 

4.16

4.45 

4.62

4.82

4.82 

4.70 

4.58

4.21 

4.06

3.70 

4.61

3.48

3.43 

3.43 

3.46

3.55 

3.40

Suspended sediment at sampling points 

indicated (percent by weight)

A

1.80 

1.46

1.15 

1.16 

1.17 

.97 

1.09 

1.11

1.06 

1.06 

.99 

.94 

.89 

.89

.75 

.69

.65 

.65 

.64 

.61 

.60 

.60

.58 

.59 

.58 

.56 

.55 

.55

.58 

.74

.55 

.52

.57 

.57 

.58 

.56 

.55 

.56

.43 

.42 

.39 

.38 

.39 

.39

.35 

.32

.41 

.40 

.38 

.43 

.41 

.42

.35 

.36 

.32 

.29 

.28 

.29

.22 

.20

B

1.81 

1.47

1.16 

1.16 

1.12 

1.19 

1.11 

1.1C

1.05 

1.06 

.99 

.94 

.89 

.88

.75 

.68

.66 

.66 

.65 

.61 

.61 

.60

.59 

.59 

.58 

.53 

.55 

.54

.58 

.73

.56 

.52

.59 

.56 

.56 

.56 

.55 

.54

.42 

.41 

.40 

.39 

.40 

.38

.35 

.33

.40 

.40 

.38 

.41 

.42 

.42

.35 

.36 

.32 

.29 

.29 

.28

.22 

.20

C

1.82 

1.46

1.15 

1.15 

1.22 

1.01 

1.08 

1.12

1.07 

1.05 

.99 

.93 

.87 

.89

.75 

.68

.66 

.66 

.66 

.61 

.61 

.59

.59 

.68 

.58 

.55 

.55 

.54

.58 

.71

.54 

.51

.56 

.56 

.57 

.55 

.54 

.54

.42

.41 

.40 

.38 

.39 

.38

.34 

.31

.41 

.39 

.39 

.41 

.41 

.41

.35 

.35 

.32 

.29 

.29 

.29

.22 

.20

D

1.83 

1.45

1.13 

1.17 

1.08 

1.19 

1.08 

1.11

1.07 

1.05 

.99 

.94 

.90 

.90

.74 

.67

.66 

.66 

.65 

.61 

.61 

.60

.58 

.59 

.57 

.55 

.56 

.54

.58 

.71

.55 

.54

.58 

.58 

.58 

.55 

.56 

.56

.42 

.41 

.39 

.38 

.39 

.39

.34

.32

.39 

.39 

.38 

.42 

.41 

.42

.35 

.36 

.32 

.29 

.29 

.28

.22 

.21

Type of 

sample

I 

I

I 

Ix

Sx 

I 

Ix

Sx

I 

8 

I 

I 

I 

8

I 

I

I

ly

Sy

ly

Sy

I 

S 

I 

I 

I 

8

I 

I

I 

I

I 

Ix

Sx 

I 

Ix

Sx

I

8 

I 

I 

I

S

I

I

I

ly

Sy

ly

Sy

i 

8 

I 

I 

I 

S

I 

I
QUANTITIES OF SUSPENDED SEDIMENT 67

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1985, 

to Sept. SO, 1936 Continued

Date

19S5

Sept. 22............ 

1 -~i , 

Sept. 23............

i ; - ~ i ' 

S2pt:24.._.____.___

Sept. 25... __ .... 

Sept. 26 ______ .

S3pt. 27.. ....... 

\ 

Sept 23. _ ........

Sept. 29............ 

Sept. 30 _____ ...

Oct. 1... _..,..-.__.

Oct. 2.............. 

Oct. 3.............. 

Oct. 4.............. 

Oct. 5..... ____ . 

Oct. 6.............. 

Oct. 7.............. 

Oct. 8.............. 

Oct.9...______'__...

Time

9:00 a. m ............

9:10 a.m. ...........

6:40 a.m.. __ . __ .

8:50 a. m _____ ..

* i 1 ' ' 

9:30 a. m _____ .

6:50 a. m ............

8:50 a.m. ...........

9:00 a. m. ...........

8:50 a. m....... _ ..

1

4:15 p. m ____ .. ...

10:00 a. m. .......... 

4:20 p. m ............

9:20 a.m. _ . ....... 

4:20 p. m: ...........

9:05 a. m. ...........

8:55 a.m. ...........

9:00 a.m.. ___ _.__.__

9:50 a. m. ...........

9:50 a. m ............

9:40 a. m. ...........

4:30 p. m __ _ ......

9:00 a. m ... ..... 

4:50 p.m. ...........

Gage 

height 

(feet)

3.26 

3.08

2.94 

2.88

2.80

2.74 

2.69 

2.67

2.74 

2.52

2.43 

2.73

3.00

2.85 

3.50 

8.32

8.34 

7.68

6.68 

5.67

5.76

13.60 

13.45

9.62

8.77

6.88 

6.47

6.06 

6.04

5.83 

5.66

5.31 

5.12

4.93 

4.87

4.76 

4.69

4.51 

4.39

4.34 

4.21

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.17 

.16

.14 

.14 

.13 

.16 

.16 

.17

.14 

.13 

.15 

.14

1 P

!l8

.12 

.12

.13 

.14 

.14 

.16 

.17 

.16

.18 

.18 

.23 

.21 

.36 

.34

.81 

.98

2.11 

2.17

2.65 

2.63 

2.64 

4.25 

5.31

4.74 

5.48

4.75 

4.59

3.67 

3.20

2.14 

1.83

1.35 

1.21

.91

.85

.70 

.67

.50 

.48

.52 

.42

B

0.18 

.16

.14 

.13 

.13 

.16 

.16 

.15

.14 

.12 

.15 

.14 

.15 

.17

.13 

.11

.14 

.14 

.13 

.17 

.16 

.16

.18 

.19 

.23 

.21 

.39 

.33

.81 

.98

2.11 

2.18

2.63 

2.64 

2.64 

4.49 

5.48

4.84 

5.41

4.76 

4.53

3.70 

3.19

2.14 

1.84

1.35 

1.22

.90

.85

.69 

.68

.61 

.56

.45 

.43

C

0.17 

.16

.14 

.13 

.12 

.16 

.15 

.15

.14 

.13 

.16 

.14 

.14 

.17

.13 

.11

.13 

.15 

.14 

.16 

.17 

.17

.19 

.19 

.22 

.21 

.34 

.33

.81 

.99

2.11 

2.18

2.63 

2.69 

2.60 

4.02 

5.69

4.82 

5.31

4.76 

4.53

3.68 

3.18

2.14 

1.83

1.35 

1.22

.91

.84

.70 

.67

.58 

.44

.45 

.43

D

0.17 

.15

.13 

.14 

.13 

.15 

.16 

.15

.13 

.12 

.15 

.14 

.14 

.17

.13 

.12

,14 

.15 

.14 

.16 

.17 

.16

.18 

.19 

.22 

.21 

.31 

.32

'.83 

.99

2.08 

» 2.17

2.55 

2.59 

2.54 

4.37 

5.57

4.76 

5.38

4.74 

4.53

3.69 

3.20

2.14 

1,82

1.35 

1.23

.91 

.85

.70 

.68

.51 

.60

.45 

.43

Type of 

sample

I 

I

I 

Ix

Sx 

I 

Ix

Sx

I

S 

I 

I 

I

S

I I

I ly

Sy

iy

Sy

I

S 

I 

I 

I

S

I I

I I

I

Ix

Sx 

I 

I

I

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I

I

I 

I
68 SEDIMENT IN COLOKADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 30, 1936 Continued

Date

193S 

Oct. 10.............

Oct. 11.. ...........

Oct. 12_. ........... 

Oct. 13............. 

Oct. 14.... ._._.____ 

Oct. 15.-. ......

Oct. 16. 

Oct. 17. .........

Oct. 18.... .........

Oct. 19- .-

Oct. 20.--....... ...

Oct. 21.... ......

Oct. 22.--.-.... _ . 

Oct. 23.. ----. '' 

Oct. 24-. ...

Oct. 25 ..........

Oct. 26 

Oct. 27-. .... ._ 

Oct. 28- ........ 

Oct. 29.. ... 

Oct. 30-. .-I.

Oct. 31. ..... ....

Nov. 1... ....... 

Nov. 2... ......

Time

10:20 a. m..- ____

9:20 a. m. ...........

4:50 p. m. _____ .

9:10 a. m... ----- ...

9:50 a. m . ___ ._ 

3:50 p. m. _____ _

9:00 a. m. _____ _ 

4:20 p. m. __ . __ .

9:40 a. m __ _ . 

3:20p. m ______ .

8:50 a. m_. ---------

3:15 p. m _____

9:00a.m_. .-.-.--.

3:30 p.m. ........

10:10 a.m.. .........

3:50 p. m _____ ...

9:15 a. m... --------- 

3:50 p. m ______ .

9:00 a. m.. _____ .

9:10 a. m.. .-----.-..

10:05 a. m... ___ .

9:10 a. m-. ----------

8:20 a. m. --..... -

8:30 a. m-. ____

9:40 a. m. ........... 

3:50 p. m... .........

9:20 a. m.... _ . _ . 

3:50 p. m ............

Gage 

height 

(feet)

4.13 

4.04

3.94 

3.74

3.81 

3.75

3*61 

3.59

3.43 

3.43

3.18 

3.23

3.12 

3.06

3.11 

3.06

3.01 

2.97

2.89 

2.85

2.86 

2.90

2.86 

2.82

2.98 

2.94

2.83 

2.82

3.25 

3.98

3.53 

3.48

3.52 

3.40

3.21 

3.19

3.10 

3.07

3.14 

3.19

3.18 

3.07

3.25 

3.22

3.34 

3. 36

3.35 

3.57

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.44 

.41

.34 

.28

.27 

.25

.23 

.22

.19 

.18

.16 

.16

.14 

.13

.13 

.13

. .12 

.12

.11 

.10

.10 

.11

.11 

.11

.11 

.12

.12 

.11

.11 

.13

.15 

.12

.14 

.16

.17

.15

.18 

.21

55 

.43

.59 

.37

.28 

.25

.22

.22

.21 

.19

B

0.44 

.41

.33

.26 

.25

.23 

.22

.19 

.18

.16 

.16

.15 

.14

.13 

.12

.12 

.12

.11 

.12

.11 

. 11

.11 

.11

.12 

.11

.11 

.11

.13 

. .11

.15 

.13

.13

.16

.17 

.16

.18 

.22

.49 

.49

.47 

.38

.27 

.25

.23

.22

.21 

.19

O

0.44 

.41

.34 

.24

.27 

.25

.23 

.22

.19 

.19

.16 

.16

.14 

.14

.13 

.13

.12 

.12

.13 

.09

. 11 

.12

.12 

.12

.12 

.11

.11 

.10

.11 

.13

.15 

.13

.14 

.16

.17 

.16

.18 

.22

.50

47

.47 

.38

.27 

.25

.24 

.22

.21 

.20

D

0.44 

.41

.33 

.30

.27 

.25

.21 

.22

.19 

.19

.16 

.14

.15 

.13

.13 

.13

.12 

.12

.13 

.10

.11 

.11

.11 

.12

.12 

.12

.11 

.10

.11 

.14

.15 

.13

.14 

.15

.16 

.18

.18 

.23

.53

.47

.47 

.39

.27 

.25

.23 

.23

.21 

.20

Type of 

sample

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I
QUANTITIES OF SUSPENDED SEDIMENT 69

TABLE 10. Suspended-sediment concentration in individual samples- collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 193B, 

to Sept. SO, 1986 Continued

Date

1935 

Nov. 3. 

Nov. 5 . 

Nov. 6. 

Nov. 8... ....-..

Nov. 10-. _____

Nov. 11. . .

Nov. 12.. 

Nov. 13-. 

Nov. 14.. __ . _ . 

Nov. 15.. ___ . ...

Nov. 16.. ....

Nov. 17.. __ . _ .

Nov. 18- 

Nov. 19.. _ -

Nov. 20.. __ ......

Nov. ?1 ............

Nov. 22. _ . _ . ...

Nov. 23. _____ .. 

Nov. 24..... .......

Nov. 25 .... 

Nov. 26. _____ .

Time

9:40 a. m_. _____ .

8:20 a. m_. _ .......

8:20 a. m__ ___ ...

4-Qft T\ TT1

11:20 a. m __ ....

8:30 a. m. _____ .

8:40 a. m. ... 

10:15 a. m. ..........

8:30 a. m.. __ . .....

9:00 a.m.... _ . _ . 

4:50 p. m ............

4:00 p. m ............

10:00 a. m.. ___ .

8:15 a. m. ...........

3:10 p.m..... ___ .

9:00 a. m. ...........

3:30 p. m ____ ....

8:40 a. m.. ___ . ...

3:15 p.m.. ___ ...

8:30 a. m- .__... 

3:20 p. m ............

8:20 a. m .... ..... 

3:30 D. m .

Gage 

height 

(feet)

3.22 

3.20

3.37 

3.37

3.41 

3.47

3.44 

3.48

3.50 

3.53

3.64 

3.62

3.63 

3.68

3.72 

3.68

3.74 

3.80

3.73 

3.72

3.65 

3.68

3.80 

3.87

3.92 

3.85

3.92 

3.90

3.90 

3.92

3.86 

3.85

3.74 

3.74

3.77 

3.68

3.68 

3.63

3.64 

3.67

3.77 

3.81

3.73

3.74

3.81 

3.86

3.81 

3:84

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.15 

.15

.14 

.14

.13 

.13

.13 

.13

.12

.11

.13 

.13

.12 

.13

0.12 

.12

.12 

.12

.13 

.13

.13 

.11

.11 

.11

.11 

.12

.12 

.10

.11 

.11

.10 

.10

.10 

.10

.09 

.09

.10 

.09

.10 

.08

.08 

.09

.11 

.11

.12 

.10

.11 

.10

B

0.15 

.13

.16 

.14

.14 

.13

.13 

.12

.11 

.13

.12 

.12

.12 

.13

0.12 

.12

.13

.12

.13 

.12

.12 

.12

.13 

.11

.12 

.12

.11 

.12

.11 

.11

.11 

.10

.10 

.09

.09 

.09

.09 

.09

.09 

.08

.08 

.09

.11 

.11

.12 

.11

.11 

.11

C

0.16 

.15

.16 

.15

.12 

.14

.14 

.13

.12 

.12

.13 

.12

.13 

.13

0.13 

.12

.13 

.13

.12 

.13

.12 

.12

.12 

.12

.12 

.11

.11 

.11

.10 

.11

.10 

.11

.11 

.09

' .10 

.09

.10 

.09

.09 

.08

.08 

.10

.11 

.11

.12 

.11

.12 

.10

D

0.16 

.16

.15 

.14

.14 

.14

.13 

.13

.12 

.12

.13 

.13

.12 

.13

0.13 

.13

.13 

.13

.13

.14

.12 

.13

.11 

.11

.13 

.11

.11 

.11

.11 

.10

.10 

.10

.10 

.10

.10 

.10

.11 

.10

.09 

.09

.08 

.10

.11 

.11

.12 

.10

,10

.11

Type of 

sample

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I
70 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. SO, 19S6- Continued

Date

1935 

Nov. 27 _______

Nov. 28...... __ .. 

Nov. 29............

Nov. 30............

Dec. 1..... .........

Dec. 3. . ....... .

Dec. 4..............

Dec. 5.............. 

Dec. 6..............

Dec. 7... ..... .....

Dec. 8-.....-.-..... 

Dec. 9 ..........

Dec. 10 -

Dec. 11 . 

Dec. 12...- ......

Dec. 13- 

Dec. 15 ..........

Dec. 16...... ....... 

Dec. 17 ..........

Dec. 18 .... _ ...

Dec. 20 .... .....

Time

8:20 a. m..... ___ . 

3:15 p. m ............

9:00 a. m. _____ 

3:05 p. m ............

3:15 p. m.. ..........

8:40 a.m. ...........

4:00 p. m ............

10:00 a. m.. ____ .

4:40 p. m ............

3:15 p. m....... _ ..

9:00 a. m. ...........

3:10 p. m.. ..........

3:25 p. m ...........

8:20 a. m. ........... 

3:25 p. m ............

4:00 p. m ...........

4:00 p. m...... .....

10:15 a.m.. ......... 

3:15 p. m ...........

3:00 p. m.. ..........

4:00 p. m.. __ . .....

8:35 a. m.. ..........

3:20p. m.. . ___ .

8:40 a. m.. .... .... 

4:10 p. m ..- ... .

8:30 a. m. ........... 

3:25 p. m ............

4:00 p.m.. _ .......

4:00 p. m ............

8:35 a. m_. ____ . 

3:10 p. m._... _ ....

8:30 a. m.... ........

8:40 a. m ______

3:25 p. m .. . 

8:40 a. m. .. . 

3:10 n. m 

Gage 

height 

(feet)

3.79 

3.78

3.80 

3.84

3.68 

3.62

3.62 

3.65

3.70 

3.71

3.72 

3.76

3.73 

3.79

3.77 

3.76

3.68 

3.69

4.79 

4.49

4.15 

3.%

3.53 

3.45

3 18 

3.12

3.10 

3.12

3.14 

3.10

3.07 

3.05

3.06 

3.11

3.13 

3.13

3.17 

3.20

3.10 

3.10

2.96 

2.90

2.76 

2.73

2.77 

2.82

2.81 

2.82

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.10 

.09

.12 

.11

.11 

.11

.15 

.14

.16 

.12

.12 

.10

.11 

.10

.10 

.09

.10 

.09

.10 

.13

.19 

.24

.22

.17

.13 

.13

.13 

.10

.09

.08

.08 

.07

.09 

.09

.10 

.10

.09 

.09

.09 

.08

.09 

.08

.10 

.10

.10 

.10

.09 

' .08

B

0.10 

.09

.13 

.11

.12 

.11

.16 

.15

.16 

.13

.11 

.10

.11 

.10

.11 

.09

.09 

.09

.10 

.14

.20

.24

.21 

.17

.13 

.13

.12 

.10

.09 

.08

.10 

.07

.10 

.08

.10 

.10

.09 

.08

.09 

.09

.09 

.10

.11 

.08

.09 

.09

.08 

.08

C

0.11 

.10

.12 

.13

.11 

.11

.16 

.15

.14 

.12

.11 

.11

.11 

.10

.10 

.09

.09 

.10

.10 

.13

.19 

.23

.21

.16

.14 

.12

.13 

.09

.09 

.08

.07 

.06

.09 

.08

.10 

.11

.10 

.08

.09 

.08

.09 

.10

.10 

.08

.09 

.07

.08 

.07

D

0.10 

.11

.11 

.12

.10 

.11

.15

.15

.14

.12

.12 

.11

.10 

.10

.10 

.10

.09 

.10

.09 

.13

.20 

.23

.21 

.16

.13 

.14

.12 

.09

.08 

.07

.09

.07

.09 

.08

.10 

.10

.09 

.09

.09 

.08

.09 

.09

.10 

.08

.09 

.08

.09 

.08

Type of 

sample

I 

I

I 

I

I

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

I 

I

r i

r 

r

r 

r

r

si

r i

r i

i i
QUANTITIES OF SUSPENDED SEDIMENT 71

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. SO, 1936 Continued

Date

19S5 

Dec 21

Dee. 22- -.-.--

Dec. 23 

Dec. 26 

Dec. 27 

Dec. 29 _ 

Dec. 30 - .

Dec. 31 

19S6 

Jan. 1. -------- 

Jan. 8 . 

Jan. 9. ~~- 

Jan. 10 ___ - _ ...

Jan. 11-,....,..-...

Jan. 12...... ... ....

Time

8:40 a. m... __ .....

3:20 p. m--.-.. __ _

8:40 a. m.. ...... _ _

3:20p. m.... _ . _ .

8:35 a. m. .

10:00 a. m._ __ ....

3:50p. m..--.. ...

10:00 a. m_ __ ......

3:40 p. m. _____ _

8:40 a. m. __ . _ ._

3:15 p. m _ _._. _ ..

3:40 p. m. _ . _ ....

8:40 a. m.... ......

9:00 a. m... __ ...

3:30 p. m.._ _ ......

3:40 p. m. _ . ___ .

4:00p. m_. ..........

9:00 a. m..... _ ..._

3:20p. m. ___ ...._

8:40 a. m...-. _ .. .

3:30p. m........ ....

8:30 a. m_ __ ...... 

3:25 p. m ____ . _ .

8:30 a.m. _____ ..

8:20 a. m.... ........

3:25 p. m...........

2:50p. m. _____ _

10:05 a. m .... .__. ...

3:20 p. m .... .

3:00 p.m... .........

Gage 

height 

(feet)

2.80 

2.78

2.51 

2.48

2.07 

1.91

1.80 

1.80

1.76 

1.71

1.64 

1.60

1.64 

1.68

1.79 

1.80

1.99 

1.98

2.13 

2.17

2.41 

2.35

2.11

2.21 

2.24

2.44 

2.46

2.53 

2.65

2.53 

2.40

2.53 

2.55

2.59 

2.58

2.50 

2.55

2.54 

2.49

2.26 

2.22

2.57 

2.68

2.77 

2.84

2.74 

2.74

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.09 

.08

.08 

.07

.07 

.08

.cr

.06

.06 

.05

.06 

.06

.07 

.06

.07 

.06

.07 

.06

.09 

.08

.06 

.06

.08

.06 .10"

.06 

.06

.08 

.06

.07 

.08

.07' 

.07

.07 

!07

.06 

.07

.06 

.05

.05 

.06

.05 

.06

0.05 

.08

.06 

.07

B

0.08 

.08

.07 

.07

.08 

.07

.07 

.06

.06 

.05

.05 

.06

.06 

.07

.06 

.06

.07 

.06

.09 

.07

.07 

.06

.07

.07 

.08

.06 

.06

.06 

.06

.07 

.08

.07 

.01

.07 

.07

.07 

.08

.06 

.07

.05 

.06

.05 

.06

0.05 

.07

.08 

.08

C

fo. 10

.08

.07 

.08

.06 

.06

.07 

.06

.05 

.05

.06 

.05

.06 

.05

.06 

.06

.07 

.08

.09 

.08

.06 

.06

.08

.08 

.08

.06 

.06

.06 

.06

.03 

.08

.07 

.08

.08 

.07

.07 

. -07

.06 

.07

.06 

.05

.05 

.06

0.07

.07 

.07

D

0.08 

.08

.07 

.07

.06 

.07

.06 

.06

.05 

.05

.05 

.06

.06 

.06

.06 

.06

.06 

.06

.16 

.06

.07 

.06

.07

.08 

.09

.06 

.06

.06 

.06

.08 

.07

.08 

.08

.07 

.07

.06 

.07

.06 

.06

.06 

.16

.05 

.05

0.05 

.08

.07 

.07

Type of 

sample

I 

I

I 

1

I 

I

I 

I

I 

I

I

I

I

 I

I 

I

I

I

I 

I

I 

I

I

I 

I

I

I

I

I

I

I

I 

I

I 

I

I 

I

I 

I

I

I

I

I

1 

I

I 

I
72 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration i'n individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 30, 1936 Continued

Date

1936

Tan 14.

Ta-n 1 *\

Jan. 17 

Jan. 18 -

Tan 10

Ton 94

Tan 9^

Jan. 29... - -

Ton 3ft

Jan. 31 

Feb. 1. -

Feb. 2....... -

Feb. 3 -

Feb. 4.. _ ..... 

Teh. 5... 

Teb.6-. ..

Time

8:30 a. m

3:60 p. m

8:10 a. m _ . ___ _

8:15 a. m.._. ____ .

3:30p. m ______

9:20 a. m_ _____ _

4:30 p. m. ...........

8:20 a. m__. __ .___

8:25 a.m., __ . _ _

3:25 p. m ___ . _ .

8:15 a. m ............

8:25 a. m._ _____ _

10:30 a. m. ..........

3:40 p. m. ...........

3:30 p. m ______ .

2:25 p. m _ 

9:00 p. m. ..........

8:40 a. m ............

3:35 p. m __ ........

8:20 a. m

8:20 a. m ............

3:20 P. m...-_.- __

Gage 

height 

(feet)

2.64 

2.68

2.60 

2.69

2.74 

2.86

2.91

2. 88

3.09 

3.24

3.27 

3.36

3.34 

3.31

3.19 

3.18

3.15 

3.19

2.98 

3.02

2.95 

2.91

2.80 

2.72

2.71 

2^69

2.65 

2.64

2.64 

2.66

2.83 

2.96

3.05 

3.12

, 3.20 

3.27

3.38 

3.34

3.51 

3.40

3.41 

3.24

3.63 

3.54

3.53 

3.47

3.60 

3.57

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.06 

.06

.06 

.05

.06 

.05

.07 

.06

.06 

.07

.06 

.06

.07 

.06

.08 

.07

.08 

.07

.06 

.06

.05 

.06

.07 

.06

.06 

.06

.05 

.06

.05 

.04

.06

.05

.06 

.06

.06 

.07

.07 

.08

.14 

.15

.15 

.16

.16 

.16

.16 

.16

.30 

.23

B

0.06 

.07

.05 

.05

.06 

.06

.06 

.06

.06 

.06

.06 

.06

.06 

.05

.07 

.08

.06 

.08

.06 

.06

.06 

.06

.07 

.07

.07 

.06

.06 

.06

.04 

.04

.06 

.05

.06 

.05

.07 

.07

.08 

.08

.14 

.15

.17 

.17

.16 

.16

.17 

.17

.32 

.23

O

0.07 

.08

.05 

.06

.06 

.08

.07 

;05

.06 

.06

.06 

.05

.06 

.05

.08 

.08

.07 

.06

.07 

.06

.05 

.05

.08 

.06

.07 

.06

.06 

.06

.05 

.04

.06 

.05

.06 

.06

.07 

.07

.08 

.08

.15 

.16

.15 

.17

.17 

.17

.18 

.17

.30 

.22

D

0.06 

.08

.06 

.06

.06 

.06

.07 

.05

.06 

.06

.06 

.06

.07 

.06

.07 

.07

.08 

.08

.06 

.06

.05 

.05

.07 

.06

.07 

.06

.06 

.06

.05 

.03

.06 

.05

.06 

.05

.08 

.08

.08 

.07

.15 

.16

.17 

.16

.16 

.18

.19 

.18

.30

.24

Type of 

sample

I 

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I 

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I

I

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I
QUANTITIES OF SUSPENDED SEDIMENT 73

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1985, 

to Sept. 30, 1936 Continued

Date

1936 

Feb. 7 ..... -

Feb. 8 .... ....

Feb. 9 ..... ... ...

Feb. 10 - 

Feb. 11 

Feb. 12 , 

Feb. 13 

Feb. 15 

Feb. 16 

Feb. 17 

Feb. 18.. . 

Feb. 19 

Feb. 21 . 

Feb. 22 

Feb. 23 - 

Feb. 24. 

Feb. 25 ..- 

Feb. 26 

Feb. 27 

Feb. 28 .

Feb. 29 ..... .

Mar. 1. ...... ......

Time

8:50 a. m .. . .. 

2:30 p. m._ .... .

9:25 a. m._ ____ ...

3:05 p. m ______ .

8:20 a.m..... __ ...

2:30 p. m ______ 

8:40 a. m __ ... .. .

8:50a. m. ...

3:40 p. m ____ . ...

8:20 a. m.. 

8:20 a. m_. _ .. 

8-20 a. m__.-_ __ ...

10:20 a. m. __ . ....

8:10 a. m... .........

8:25 a. m-. ___ ....

8:20 a. m-... ____ .

3:05 p. m ______ .

9:55 a. m. _. 

8:15 a. m... ___ 1.

8:25a.m.. ......

3:35 p. m._ ..........

8:50 a. m_- ..........

8:45 a. m.. ..........

8:25 a. m-- ......

11:00*. m 

5:40 D. m ____ . ....

Gage 

height 

(feet)

3.30 

3.21

3.00 

2.96

3.23 

3.32

3.46 

3.40

3.29 

3.18

2.98 

2.91

2.77 

2.87

3.14 

3.06

3. 12 

3.15

3.24 

3.39

3.46 

3.50

4.01 

4.13

4.39 

4.32

4.32 

4.36

4.27 

4.21

4.33 

4.34

4.34 

4.39

4.21 

4.10

4.37 

4.60

4.69 

4.56

3.99 

4.01

4.24 

4.36

5.26 

5.30

4.93 

4.85

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.17 

.18

.17 

.17

.16 

.16

.16 

.10

.10 

.09

.13

.08

.10

.08

.07 

.07

.06 

.07

.12 

.16

.09 

.10

.12 

.13

.16 

.16

. 15 

.16

.16 

.15

.15 

, .17

.18 

.19

.19 

.18

.18 

.19

.32 

.32

.19 

.16

.26 

.29

.28 

.42

.48 

.46

B

0.18 

.16

.17 

.17

.15 

.18

.17 

.12

.10 

.08

.12 

.08

.09

.08

.08

.06

.07 

.07

.12 

.15

.09 

.09

!l3

.16 

.16

.15 

.16

.16 

.15

.15 

.17

.18 

.18

.18 

.19

.18 

.19

.33 

.32

.18 

.17

.26 

.29

.29 

.41

.49 

.46

C

0.17 

.16

.19 

.16

.16 

.20

.19 

.11

.09 

.09

.11 

.08

.09 

.07

.08 

.07

.08 

.07

.12 

.14

.09 

.11

. 12 

.13

.17 

.17

.17 

.16

.17 

.15

.16 

.17

.19 

.19

.19 

.19

.18 

.20

.33

.34

.19 

.19

.25 

.29

.28 

.42

.48 

.46

D

0.20 

.17

.18 

.16

.17 

.18

.15 

.11

.09 

.08

.11 

.08

.08 

.08

.07 

.07

.09 

.07

.14 

.14

.09 

.11

.12 

. 14

.16 

.17

.16 

.15

.16 

.15

.16 

.17

.18 

.19

.19 

.18

.18 

.23

.31

.32

.19

.17

.26 

.30

.27 

.42

.49 

.46

Type of 

sample

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74 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. SO, 1936 Continued

Date

1938 

Mar. 2............

Mar. 3....... ......

Mar. 4..... ....

TLTar 7

Mar. 8.. ...........

Mar. 9--.-... _ ...

Mar. 10.. ..........

Mar. 11.... ........

Mar. 12.. ..........

Mar. 13............

Mar. 14. _._._.._.__

Mar. 15...-._...... 

Mar. 16............

Mar. 17. ...........

Mar. 18--....-...-. 

Mar. 19... .........

Mar. 20.. ........ ..

Mar. 21--.- .

Mar. 22............ 

Mar. 23.-. ..-.. 

Mar. 24.. _____..._.

Mar. 25.. .......... 

Mar. 26............

Time

9:00 a. m. ...........

8:45 a. m.... __ ...

9:00 a. m_... ........

3:10p. m..... .......

9:00 a. m. __ ...

3:30p. m... .........

3:20p. m_... __ ..

5:00 p. m.-___._.____

10:00 a. m.._.L---_-

4:30p. m._ __ .. ...

8:20 a. m...... __ _

3:10 p. m._. . .

8:10 a. m__ ..........

3:20 p. m...... _ ...

8:40 a. m. ...........

3:05 p. m... .......

8:10 a. m ...__._..

3:15 p. m.. ........

3:15 p. m_.____ _ ...

8:30 a. m. ...........

4:00p. ni... .........

9:40 a. m.... ____ _ 

4:00 p. m._. __ ...

9:25 a. m_. ...... ...

2:45 p. m

3:30 p. m_____. ______ 

8:10 a. m_. ..........

3:10 p. m......

8:15 a. m. ....... ....

3:10 p. m. ...........

8:30 a. m.. _ ... _ .

3:30p. m.. _____

10:20 a. m. .......... 

4:10 p. m ...

8:40 a.m. ........... 

3:15 p. m....

9:00 a. m. __._. 

3:20 p. m............

8:20 a.m...... . 

3:15 p. m

8:20 a.m.... .__._.._ 

3:15 p. m _..____._

Gage 

height 

(feet)

4.50 

4.40

4.20 

4.12

3.95 

3.87

3.86 

3.88

4.69 

5.04

5.68 

5.49

5.66 

5.67

5.84 

5.51

5.77 

5.52

5.62 

5.47

5.72 

5.60

5.81 

5.70

6.14 

5.90

5.99 

5.90

5.81

5.93 

6.13

6.30

6.34 

6.24

6.21

6.22

5.71 

.5.84

5.68 

5.57

5.35 

5.50

5.51 

5.41

5.49 

5.56

5.54 

5.42

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.39 

.36

.35 

.36

.31 

.29

.25 

.23

.24 

.24

.41 

.44

.60 

.72

1.12 

1.23

1.27 

1.29

1.09 

1. 11

1.03 

.99

.90

.85

.75 

.80

.72 

.75

.73

.66 

.63

.62

.66 

.57

.49 

.50

.49 

.49

.45 

.44

.41 

.40

.36 

.38

.34 

.34

.33 

.35

B

0.39 

.36

.36 

.36

.30 

.29

.25 

.24

.25 

.24

.40 

.44

.60 

.73

1.12 

1.22

1.27 

1.29

1.10 

1.11

1.04 

1.00

.91

.84

.74 

.79

.78 

.82

.74

.68 

.63

.61

.69 

.64

.53 

.51

.47

.50

.44 

.45

.41 

.35

.37 

.37

.35 

.34

.34 

.36

C

0.39 

.36

.37 

.36

.30 

.29

.25 

.24

.25 

.25

.40 

.44

.60 

.74

1.12 

1.22

1.26 

1.30

J. 10 

1.11

1.09 

.99

.86 

.85

.74 

.79

.79 

.84

.77

.67 

.64

.60

.72 

.56

.51 

.50

.48 

.49

.47 

.46

.41 

.35

.36 

.37

.36 

.34

.34 

.36

D

0.39 

.39

.37 

.36

.30 

.29

.25 

.25

.25 

.25

.41

.45

.60 

.73

.1.10 

1.22

1.26 

1.29

'1.10 

1.10

1.09 

1.03

.85 

.85

.76 

.79

.86 

.92

.71

.66 

.64

.63

.71 

.56

.51 

.51

.48 

.50

.46 

.46

.44 

.35

.37 

.37

.35 

.34

.34

.38

Type of 

sample

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QUANTITIES OF SUSPENDED SEDIMENT 75

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 80, 1936 Continued

Date

1SS6 

Mar. 27............

Mar. 28.... ........

Mar. 29............

Mar. SO............

Apr. 1 . _

Apr. 2 __ . ____ .

Apr. 4....... .......

Apr. 5__ _____ ...

Apr. 6. _______ .

Apr. 7 ..........

Apr. 8 _______ .

Apr. 9. _ ____ ..

Apr. 10... ..........

Apr. 12 .........

Apr. 13 ..........

Apr. 14 .... __

Apr. 15 ..........

Apr. 16 ..........

Apr. 17... .......

Apr. 18 .........

Apr. 19... ..........

Time

2:35 p. m..... _ ....

8:30 a. m_._ __ ....

3:10 p. m . ___ '.

10:10 a. m-_. ...... ..

4:40 p. m..... .......

8:35 a. m. ...........

3:05 p. m

9:05a. m_. _ . ....

3:25 p. m ....__._

9:25 a. m_. ..........

3:15 p. m __ .

8:35 a. m... _ _ .....

3:20 p. m.__. ... 

9:15 a. m... ___ ..

3:15 p. m __ .. .....

9:20 a.m.. . ___ _

2:35 a. m... .. _ ...

10:10 a.m. ..........

8:30 a. m. ...........

3:15 p. m. ... ........

9:00 a. m. ...........

3:10 p.m... .........

8:15 a. m. ...........

3:05 p. m . 

8:15 a. m. __ .. __ _

3:15 p. m __ . ___ .

8:20a. m.. ........

3:20 p. m _____ .

4:50 p. m. ........ ...

9:45 a. m. _ . __ ..

4:10 p. m. .......... .

8:20 a.m.. ..........

3:20 p. m _____ ..

3:20 p. m ______ .

3:00 p m .. ..........

8:25 a. m.. ..........

10:15 a. m. _ ... ....

4:45 p. m. _ _ .....

Gage 

height 

(feet)

5.78 

5.66

5.41 

5.30

5.13 

5.08

5.54 

5.20

5.03

4.87

4.59 

4.50

4.64 

4.67

5.13 

5.21

5.11 

5.24

v 5. 49 

5.31

4.84 

4.91

4.98 

5.15

5.29 

5.21

4.96 

4.71

4.69 

4.53

4.56 

4.54

4.63 

5.03

6.86 

6.54

6.81 

6.53

7.28 

7.03

8.14 

9.01

9.60 

10.41

11.44 

11.87

12.21 

12.44

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.39 

.39

.37 

.37

.41 

.39

.32' 

.36

.38 

.38

.37 

.32

.31 

.24

.28 

.32

.46 

.43

.39 

.38

.39 

.39

.39 

.36

.36 

.40

.40 

.38

.29 

.27

.27 

.24

.23 

.21

.58 

.81

.89 

.93

1.07 

1.04

1.15 

1.15

1.42 

1.48

1.74 

1.64

1.62 

1.72

B

0.36 

.33

.37 

.39

.39 

.40

.32 

.36

.30 

.39

.38 

.33

.31

.25

.29 

.32

.44 

.44

.39 

.40

.39 

.39

.38 

.37

.36 

.41

.39 

.37

.29 

.28

.28 

.24

.24 

.21

.51 

.86

.87 

-.88

1.17 

1.07

1.22 

1.19

1.42 

1.52

1.66 

1.72

1.68 

1.67

C

0.35 

.43

.33 

.41

.39 

.40

.33 

.36

*.37 

.38

.38 

.34

.31

.24

.29 

.33

.46 

.43

.39 

.40

.39 

.40

.38 

.35

.35 

.39

.40 

.38

.30

.28

.27 

.23

.23 

.22

.62 

.86

.90 

.89

1.13 

1.07

1.21 

1.16

1.37 

1.46

1.68 

1.73

1.60 

1.61

D

0.34 

.40

.36 

.36

.39 

.39

.31 

.38

.38 

.38

.37 

.34

.30 

.23

.29 

.29

.46 

.44

.38 

.40

.40 

.40

.39 

.38

.36 

.40

.39 

.39

.29

.28

.28 

.24

.23 

.22

.59 

.87

.86 

.87

1.09 

1.07

1.22 

1.17

1.50 

1.52

1.56 

1.70

1.63 

1.59

Type of 

sample

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i 47-
76 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 30, 1936 Continued

Date

1936 

Apr. 20 . ... 

Apr. 21 

Apr. 22....... ..

Apr. 23. . 

Apr. 24....... ...... 

Apr. 25 

Apr. 26. 

Ar>r 97

Apr. 28 

Apr. 29.... ... ..-

May 5 

May 9 _ ... . 

May 10 _ 

May 11. ... 

May 12 ___ ... 

May 13.. .... 

Time

3:15 p. m __ . .......

3:25 p. m. ...........

9:30 a. m. .-..-....__

9:30 a. m_. ..........

8:40 a. m. ......

8:50 a. m. _____ __

8:20 a. m. .-.-.---.._

9:00 a. m.. ......

8:30 a. m_._ ____ .

8:45 a. m. ...........

9:00 a. m.. ..

9:20 a.m. ...........

8:45 a. m__ _____ .

8:35 a. m.. ..........

9:35 a. m. ...........

8:40 a. m. ...........

8:30 a. m.. ..

8:45 a. m. ______

3:00 D .m _ . ........

- Gage 

height 

(feet)

13.08 

13.45

14.40 

14.84

15.24 

15.32

15.39 

15.76

16.00 

16.36

16.87 

17.16

17.70 

18.18

18. 25 

18.20

18.20 

18. 38

18.43 

18.62

18.56 

18.66

18.55 

18.59

18.46 

18.56

18.49 

18.17

17.59 

17.40

17.13 

17.21

17.19 

17.55

18.28 

18.63

19.84 

20.22

21.32 

21.50

21.11 

20.86

20.06

- 19. 70

18.91 

18.43

17.62 

17.36

Suspended sediment at sampling points 

indicated (percent by weight)

A

1.74 

1.51

1.56 

1.48

1.55 

1.46

1.33 

1.43

1.45 

1.30

1.57 

1.38

1.70 

1.40

1.50 

1.25

1.42 

1.19

1.15 

1.27

1.28 

1.40

1.14 

1.04

1.02 

1.00

1.03

.89

.88 

.83

.89 

.80

.83

.78

.84 

.73

.85 

.99

1.05 

1.11

1.08

.86

.72 

.75

.77 

.62

.54 

.49

B

1.67 

1.47

1.81 

1.51

1.50 

1.70

1.73 

2.14

1.28 

1.36

1.42 

1.25

1.52 

1.45

1.32 

1.27

1.26 

1.47

1.31 

1.17

1.18 

1.13

1.23 

1.14

1.12 

.92

.88 

.93

.74 

.63

.92 

.72

.60 

.59

.70 

.65

.83 

.85

1.19 

.97

.95 

.84

.72 

-81

.54 

.52

.51 

.44

G

1.66 

1.57

1.76 

1.46

1.60 

1.55

1.53 

1.32

1.37 

1.21

1.43 

1.42

2.05 

1.30

1.54 

1.63

1.78 

1.54

1.70 

1.48

1.16 

1.49

1.11 

1.51

1.05 

1.04

.98 

.86

.88 

.81

.76 

.69

.62 

.66

.78 

.71

1.20 

.76

.90 

1.07

1.03

.57

.61 

.66

.64 

.58

.69 

.59

D

1.76 

1.58

1.97

1.54 

1.63

1.53 

1.56

1.33 

1.25

1.61 

1.39

1.64 

1.60

1.40 

1.21

1.47 

2.56

1.21 

1.30

1.05 

1.42

1.08 

1.01

.98 

.95

.89 

1.13

.92 

.75

.95 

.59

.61 

.65

.73

.77

.93 

1.10

1.13 

1.05

.88 

.95

.78 

.84

.60 

.62

.56

.47

Type of 

sample

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QUANTITIES OF SUSPENDED SEDIMENT 77

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1985, 

to Sept. 30, 1986 Continued

Date

19S6

May 15.----. -

May 17--..- ....

May 18... ......

May 22.. ...... ....

May 23.. ...... ....

May 25.. ....-. .

May 27... ~ -

May 28... .... -.

May 29... .........

May 31. .-.... .-

June 5. .............

June 6..... ...

Time

8:35 a. m ______ .

8:25 a. m...... _ ...

8:35 a. m. _____ .

8:45 a. m. ...........

3:45 p. m_ ______

9:00 a. m. . ..........

4:30 p. m_. _____ _

9:00 a. m..__ _ . _ .

9:00 a. m_.__ ___ _

9:00 a. m._ _____ .

4:00 p. m_ _ . ___ _

8:45 a, m. _____ .

4:30 p. m.. . ___ -

9:15 a. m_... _ .....

9:00 a. m ______ .

9:00 a. m. ...........

9:00 a. m.. ..........

8:45 a. m... ......

4:30 p. m __ . ......

9:00 a. m_. ........ 

8:30 a.m. ...........

9:00 a. m. _____

8:45 a. m ______

9:00 a. m. ___ _

8:45 a. m. . ____

9:45 a. m.. . _ ... 

4:30 D. m ............

Gage 

height 

(feet)

16.63 

16.33

16.18 

16.47

16.86 

17.41

18.00 

18.30

19.11 

19.59

20.37- 

20.86

21.51

21.77

21.95 

22.11

22.02 

21.94

22.32 

22.45

22.58 

22.51

22.17 

22.14

21.73 

21.60

21.37 

21.33

21.34 

21.34

21.24 

21.36

21.27 

21.33

21.16 

21.09

20.75 

20.85

20.98 

21.38

21.67 

21.81

21.81 

21.93

21.53 

21.18

20.59 

20.21

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.51 

.52

.46 

.49

.48 

.42

.78 

.51

.57 

.64

.62 

.56

.60 

.82

.65 

.59

.63

.68

.67 

.30

.57 

.60

.51 

.41

.71 

.54

.60 

.53

.54 

.43

.39 

.56

.63 

.41

.46 

.56

.45 

.50

.55 

.56

.53 

.49

.53 

.65

.47 

.44

.48 

.49

B

0.45 

.50

.40 

.38

.46 

.39

.54 

.41

.51 

.61

.54 

.53

.52 

.65

.54 

.55

.49 

.59

.58 

.59

.49 

.57

-.49 

.41

.49 

.44

.56 

.53

.51 

.39

.36 

.50

.51 

.38

.41 

.51

.43

.49

.48 

.56

.53 

.41

.51 

.57

.49 

.44

.50 

.47

O

0.51 

.46

.46 

.34

.47 

.38

.45 

.42

.44 

.59

.45 

.52

.58 

.72

.57 

.61

.48 

.60

.65 

.54

.67 

.60

.42 

.37

.44 

.46

.48 

.48

.52 

.34

.40 

.53

.63 

.44

.34

.49

.42 

 47

.50 

.54

.45 

.47

.47 

.59

.41 

.43

.53 

.48

D

0.61 

.50

.42 

.44

.55 

.37

.47 

.48

.49 

.52

.54 

.50

.62 

.60

.60 

.63

.62 

.65

.72 

.61

.61 

.56

.48 

.44

.51 

.47

.50 

.60

.56 

.44

.37 

.48

.59

.38

.42

.52

.41 

.50

.53 

.56

.47 

.45

.58 

.67

.43 

.50

.55 

.46

Type of 

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78 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1985, 

to Sept. SO, 1986 Continued

Date

1936

June 16. _ ---- _ -

June 21 __.-____-- 

June 22- ______ 

June 23 .. _____ . 

June 24.. _----...

June 29....... _ ..

June 31

Time

9:15 a. m. ...........

8:45 a. m. ..........

9:30 a. m. ______

9:30 a. m._. _ . ....

9:00 a. m. __ ___

9:00 a. m._ _ .... ...

4:30 p. m .. ... ...

8:45 a. m. ______

8:50 a. m..., _ . _ ,

10:00 a. m-..-----.-.

9:15 a. m.-- __ .....

3:30 p. m... .........

9:30 a. m.. _ ... ....

8:45 a. m_. .......... 

7:00p. m ____ '.....

9:00 a. m__ ..........

9:00 a. m. ......... ..

9:30 a. m. ........... 

4:30 p. m ............

9:40 a. m. ...........

4:10 p. m ............

9:^0 a. m.. ____ ..

9:00 a. m

4:20 p.m... ----.-..-

Gage 

height 

(feet)

19.35 

19.03

18.57 

18.33

17.96 

17.75

17.47 

17.38

17.33 

17.35

17.80 

18.03

18.17 

18.09

18.02 

18.05

17.96 

17.82

17.67 

17.67

17.45 

17.48

17.31 

17.13

16.90 

16.89

16.75 

16.61

16.42 

16.28

16.08 

16.01

15.86 

15.60

15.36 

15.24

14.88 

14.74

14.49 

14.38

14.19 

14.14

13.84 

13.68

13.28 

13.23

13.07 

13. 08

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.46 

.44

.41 

.42

.41 

.34

.40 

.28

.45 

.38

.40 

.41

.36 

.38

.37 

.30

.30 

' .36

.31 

.31

.31 

.34

.29 

.40

.28 

.26

.27 

.31

.25 

.24

.27 

.27

.28 

.30

.26 

.27

.23

.24

.21 

.23

.21 

.19

.22

.21

.24 

.23

.23 

.20

B

0.50 

.44

.42 

.41

.40 

.37

. .41 

.28

.41 

.37

.35 

.37

.35 

.38

.40 

.30

.29 

.38

.34 

.31

.34 

.35

.32 

.34

.33

.25

.27 

.28.

.26 

.22

.29 

.24

.31 

.30

.31 

.25

.19 

.24

.21 

.18

.19 

.19

.20 

.18

.22 

.19

.20 

.18

C

0.48 

.42

.41 

.38

.41 

.40

.38 

.26

.40 

.44

.38 

.37

.34 

.36

.37 

.29

.28 

.33

.30 

.30

.32 

.32

.30 

.36

.29 

.25

.29 

.28

.27 

.21

.33 

.23

.26 

.27

.29 

.26

.19 

.24

.21 

.20

.18 

.19

.17 

.20

.29 

.20

.19 

.20

D

0.49 

.46

.39 

.36

.37 

.39

.37 

.28

.37 

.40

.37 

.39

.35 

.31

.37 

.33

.31 

.33

.40 

.34

.31 

.39

.35 

.34

.25 

.24

.32 

.36

- .24 

.28

.30 

.23

.28 

.24

.31 

.26

.22 

.23

.17 

.24

.18 

.16

.21 

.20

.23

.21

.19 

.20

Type of 

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QUANTITIES OF SUSPENDED SEDIMENT 79

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 30, 1936 Continued

Date

1986 

July 1 ..... 

July 2... ...........

Julys..............

July 4..............

July 4.. ............

July 6-.. ......... .

July 7-__. ........ .

July 8... ...........

July 9......... ....

July 10... ....... 1. .

July 11...... .......

July 12..... ........

July 13... ..........

July 14.............

July 15...... .......

July 16.:..,........

July 17... ..........

July 18.............

July 19. __ ........

July 20. ... ... ...

July 21.. . .......

July 22.............

July 23.. _ ........

July 24.............

Time

10:00 a.m..-.--.....

4:30 p. m _ .........

9:30a. m... .-...----

9:30 a. m........ ....

4:00 p. m............

9:30 a.m. ...... _ ..

3:10 p. m ............

9:30 a.m. ....... _ .

3:00 p.m... .........

9:45 a.m... .........

4:15 p. m ______ .

9:45 a. m. ...........

10:00 a. m..... __ _

9:30 a. m... __ ....

9:15 a. m. ___ . ....

4:15 p. m.-__- _ ....

9:30 a.m. ........ ...

9:30 a. m. ...........

10:30 a. m... __ ....

9:15 a. m.. ___ ...

2:45 p. m ............

9:30 a. m _____ t 

3:45 p. m _____.

9:45 a.m. .........

4:45 p. m ............

9:45 a. m. ...........

9:30 a. m ...........

4:30 p. m ...........

9:15 a. m ............

9:45 a. m.. ..........

2:45 p. m ............

Gage 

height 

(feet)

12.91

12.84

12.50 

12.37

12.12 

12.16

11.88 

11.85

11.52 

11.43

10.89 

10.71

10.35 

10.26

9.94 

9.80

9.66 

9.33

8.94 

8.79

8.93 

10.81

8.52 

8.52

13.32 

14.59

14.58 

13.67

11.59 

11.19

10.33 

10.31

9.94 

9.98

9.80 

9.66

9.15 

8.89

8.66 

8.48

8.69 

8.98

9.24 

9.16

8.89 

8.75

8.83' 

8.73

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.18 

.19

.17 

.16

.17 

.19

.13 

.17

.16 

.16

.14 

.19

.20 

.15

.13 

.10

.12 

.14

.13 

.13

.12 

.12

.30 

4.19

.80 

.82

6.13 

3.27

1.68 

1.73

3.04 

3.20

3.77 

3.41

2.41 

2.36

1.80 

1.90

1.14

.88

.89 

.86

.96

.85

.75 

.76

.67 

.56

B

0.20 

.17

.18 

.17

.16 

.17

.15 

.16

.14 

.15

.17 

.18

.18 

.16

.15 

.13

.12 

.14

.14 

.12

.13 

.13

.29 

4.20

.84 

.83

6.03 

3.23

1.68 

1.72

3.06 

3.18

3.81 

3.42

2.46

1.80 

1.88

1.16 

.89

.93

.84

.97

.84

.75 

.76

.68 

.56

C

0.19 

.16

.16 

.17

.17 

.19

.15 

.17

.16 

.15

.17 

.17

.17 

.20

.13

.12

.12 

.13

.13 

.12

.12

.12

.28 

4.12

.81

.77

6.30 

3.30

1.75 

1.86

3.09 

3.20

3.84 

3.50

2.43 

2.34

1.80 

1.89

1.16 

.89

.91 

.92

.98 

.86

.76 

.76

.68 

.56

D

0.20 

.18

.15 

.18

.15 

.18

.16 

.17

.15 

.16

.16 .17'

.19 

.17

.12 

.12

.14 

.15

.13 

.12

.13 

.12

.27 

4.11

.84 

.83

6.24 

3.29

1.69 

1.69

3,08 

3.19

3.83 

3.40

2.46 

2.33

1.80 

1.88

1.12

.88

.89 

.85

.97 

.86

.75 

.75

.65 

.56

Type of 

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80 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 80, 1936 Continued

Date

1936 

July 25 

July 26... ..........

July 27.. 

July 28.. ....... .... 

July 29.. ...........

July 30.... .........

July 31.. . ......

Aug. 1 _

Aug. 10 _ .........

Aug. 11. .. .........

Aug. 12. ...... .....

Aug. 13. ...........

Aug. 15..... __ .. 

Aug. 16... _ . __ . 

Aug. 17 ____ .....

Time

9:30 a. m . .... ..

10:30 a. m.. .... .

3:45 p. m

9:20 a. m. 

10:20 a. m. __ _-___

9:15 a. m_ .....-. 

4:30 p. m 

Gage 

height 

(feet)

8.21 

8.21

7.82 

7.78

7.76 

7.95-

7.04 

7.33

7.56 

7.25

7.33 

6.81

6.04 

5.91

6.87 

6.79

6.45 

6.31

6.27 

6.50

6.80 

6.77

8.93 

9.56

10.32 

11.84

14.39 

15.53

12.67 

12.63

13.20 

13.87

13.86 

13.31

12.52 

12.12

11.63 

11.56

10.80 

10.79

10.25 

9.87

9.50 

9.16

8.50 

8.38

8.22 

8.16

Suspended sediment at sampling points 

indicated (percent by weight)

A

0.80 

.67

.59 

.53

.61 

.66

1.33 

.90

1.06 

1.45

. 1.44 

1.16

1.11 

.91

1.05 

1.23

.99

.88

.79 

1.04

1.43 

1.55

3.26 

3.02

3.32 

5.11

6.17 

4.89

6.84 

6.21

5.32 

5.73

4.09 

2.83

3.32 

3.15

2.66 

2.81

2.51 

2.52

2.34 

1.93

2.35 

2.13

1.71 

1.64

1.54 

1.43

B

0.79 

.68

.58 

.53

.61 

.65

1.31 

.90

1.06 

1.42

1.45 

1.19

1.08 

.91

1.03 

1.23

1.00

.87

.82 

1.04

1.43 

1.52

3.33 

2.99

3.39 

5.21

5.70 

4.82

6.88 

5.93

5.20 

5.41

4.23 

3.83

3.29 

3.20

2.91 

2.75

2.60 

2.59

2.29 

1.92

2.32 

2.07

1.70 

1.62

1.54 

1.39

C

0.80

.67

.58 

.53

.61 

.91

1.33 

.91

1.05 

1.40

1.46 

1.17

1.08 

.89

1.02 

1.30

.99 

.94

.80 

1.02

1.43 

1.51

3.36 

2.93

3.29 

5.12

6.07 

4.60

6.80 

6.68

5.08 

5.34

4.06 

5.11

3.21

3.07

2.64 

2.80

2.58 

2.52

2.34 

1.89

2.38 

2.12

1.73 

1.66

1.56

1.42

D

0.80 

.68

.59

.54

.60 

.64

1.31 

.91

1.05 

1.40

1.46 

1.18

1.05 

.90

.97 

1.23

.99

.87

.80 

1.02

1.42 

1.51

3.38 

2.89

3.29

5.07

5.86 

4.68

6.90 

6.05

5.08 

5.29

4.05 

3.74

3.21

2.98

2.57

2.42 

2.52

2.32 

1.89

2.35 

2.05

1.71 

1.63

1.58 

1.43

Type of 

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QUANTITIES OF SUSPENDED SEDIMENT 81

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz., Apr. 1, 1935, 

to Sept. 30, 1936 Continued

Date

1936 

Aug. 18..........

Aug. 19............ 

Aug. 20............ 

Aug. 21..... ........

Aug. 22. ...........

Aug. 23............ 

Aug. 24...... __ . 

Aug. 25............

Aug. 26...... ... 

Aug. 27............

Aug. 28............

Aug. 29............

Aug. 30............

Aug. 31............

Sept. 1 ..... . _

Sept. 2.. _____ ..

Sept. 3. ___ . __ . 

Sept. 4.............

Sept. 5............

Sept. 6.. ........... 

Sept. 7.............

Sept. 8 ______ .

Sept. 9.. _____ . 

Sept. 10 __ . .......

Sept. 11 _ . ___ . 

Sept. 12 _____ . 

Sept. 13 ............

i Estimated.

Time

10:15 a. m. ..........

4:10 p. m _____ ..

9:20 a. m.. _ .......

10:00 a. m.. _ ......

3:30 p. m ............

10:00 a.m. ..........

9:20 a. m. ...........

9:20 a. m. ...... _ .

9:45 a. m.. ..........

9:30 a. m ....... _ .

2:30 p. m ______ .

4:00 p.m... .........

4:00 p. m ........

9:45 a. m. ...........

3:00 p. m ............

9:45 a. m. ........... 

3:45 p. m. .........

4:30 p.m..... _ ....

9:15 a. m... _ .. ...

9:30 a. m... __ .. 

4:30 p.m... .........

4:30 p. m.............

9:15 a. m ............

3:30 p. m _____ ..

9:30 a. m.. _____ .

3:45 p. m ............

9:30 a. m. ........ 

3:30 p.m. ...........

9:00 a.m... ____ . 

3:00 p.m. ...........

9:30 a. m ............

4:20 p. m __ .... ...

Gage 

height 

(feet)

8.28 

8.20

8.00 

8.32

9.84 

9.85 

8.61 

7.69 

7.47 

6.93 

6.44

5.91 

5.53

6.88

8.90 

7.11

11.90 

9.45

12.26 

13.27

11.20 

11.36

10.23 

10.56

9.86 

10.35

9.14 

9.48

8.73 

9.28

7.51

7.18 

7.38

6.85 

7.14

6.45 

6.53

6.00 

6.16

Suspended sediment at sampling points 

indicated (percent by weight)

"A

1.13 

1.24

1.49 

1.23 

1 1.40

U.60

1.72 

2.22 

2.02 

2.17 

2.06 

1.32 

.97

.92 

1.37

7.03 

3.71

2.70 

3.35

4.76 

3.95

7.29 

8.00

7.22 

6.34

4.66 

4.13

3.57 

3.23

3.47 

'2.80

. 2.60 

2.44

2.43

1.90 

1.77

1.24 

1.28

"""I."40"

1.44 

1.61

B

1.13 

1.18

1.48 

1.23

1.76 

2.19 

2.26 

2.23 

2.06 

1.33 

.98

.93 

1.36

7.14 

3.80

2.86 

3.25

5.01 

3.88

7.21 

7.98

7.34 

6.60

4.97 

4.00

3.68 

3.18

3.30 

2.91

2.62 

2.30

2.42

2.03 

1.49

1.40 

1.28

1.36 

1.36

1.49 

1.66

C

1.13 

1.19

1.47 

1.24

1.81 

1.93 

2.01 

2.18 

2.07 

1.36 

" .99

.92 

1.37

7.27 

3.78

2.89 

3.22

5.02 

4.07

7.68 

7.94

7.20 

6.51

4.70 

4.07

3.72 

3.21

3.40 

2.83

2.57 

2.47

2.42

1.96 

1.61

1.42 

1.16

1.41 

1.32

1.61 

1.69

D

1.13 

1.05

1.25 

1.20

1.70 

2.18 

2.02 

2.19 

2.08 

1.33 

.98

.94 

1.38

7.42 

3.83

2.85 

3.12

5.09 

4.01

7.85 

7.98

7.27 

6.41

4.70 

4.05

3.67 

3.15

3.30 

2.76

2.83 

2.50

- 2.32

1.99 

1.57

1.44 

1.20

1.40 

1.38

'l.38 

1.71

Type of 

sample

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82 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 10. Suspended-sediment concentration in individual samples collected from 

the Colorado River at gaging station near Grand Canyon, Ariz,, Apr. 1, 1935, 

to Sept. 80, 1986 Continued

Date

19S6 

Sept 14.... .........

Sept. 15 __ .......

Sept. 17 

Sept. 18----... _ ..

Sept. 19,...)........

Sept. 20 

Sept. 21...,.... .

Sept. 23 .......

Sept. 24. ___ ....

Sept. 25. __ .--..-.

X

Sept. 26. ... ... ..

Sept. 27............

Sept. 28..... ... .... i

Sept. 29..... .......

Sept. 30 __ . __ .

Time

9:30 a. m__ ..........

4:30 p.m. ...........

3:40 p.m... .........

3:30 p. m ___ ....

9:20 a. m. _____ .

2:50 p. m... .........

9:15 a. m. ...........

3:40 p. m ............

9:50 a. m... .........

4:30 p.m. ...........

4:30 p. m ............

9:50 a.m. ...........

4:30 p. m ............

9:30 a. m. ...........

9:30 a. m. ...........

3:45 p.m...... ......

8:45 a. m... ........

9:30 a. m.. _ .......

4:00 p. m ............

9:15 a. m. __ . ......

Gage 

height 

(feet)

6.98 

7.44

6.50 

6.72

6.21 

6.34

5.91 

6.09

5.63 

5.70

5.71 

5.64

5.53 

5.54

4.98

7.37 

4.96

5.78 

6.25

5.65 

6.00

5.56 

5.62

5.69 

5.93

4.94 

5.62

4.56 

5.76

3.99 

4.37

3.65 

3.87

Suspended sediment at sampling points 

indicated (percent by weight)

A

2.56 

2.63

1.73 

1.92

1.49 

1.45

1.38 

1.36

1.06 

1.02

.84 

.79

.72 

.68

.53

2.13 

4.41

2.31 

1.89

3.21 

2.86

2.24 

1.79

1.35 

1.27

1.91 

1.60

1.18 

1.12

1.09 

1.10

.98 

.85

B

2.82 

2.80

1.91 

1.89

1.61 

1.58

1.29 

1.24

.98 

1.00

.78 

.79

,72 

.65

.53

2.09 

4.48

2.34 

1.86

3.19 

2.88

2.19 

1.80

1.40 

1.34

1.90 

1.63

1.23 

1.18

1.06 

1.11

.98 

.85

C

2.32 

2.85

2.00 

1.86

1.37 

1.49

1.33 

1.23

1.00 

.96

.82

.78

.72 

.66

.53

2.08 

4.56

2.27 

1.90

3.12 

2.92

2.18 

1.69

1.41 

1.30

1.82 

1.60

1.27 

1.12

1.11 

1.08

.97 

.86

D

2.62 

2.39

1.94 

1.69

1.43 

1.53

1.51 

1.18

1.04 

.98

.83 

.79

.72 

.66

.53

2.05 

4.51

2.28 

1.81

3.13 

2.85

2.21

1.76

1.44 

1.29

1.90 

1.59

1.21 

1.11

1.06 

1.04

.96 

.85

Type of 

sample

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QUANTITIES OF SUSPENDED SEDIMENT 83

TABLE 11. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Willow Beach, 

Ariz., Oct. 1, 1934, to Sept. 30, 1936

1934

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._._

October

Mean 

discharge 

(secondfeet)

3,620

4,220

3,690

3,370

3,110

3,580

3,640

3, 530

3,330

3,310

3,210

3,170

3,120

3,090

2,920

2,880

2,820

2,910

2,760

2,790

2,650

2,650

2, 820

2,770

2,850

2,870

2,990

2,920

2,940

2,900

2,940

Suspended matter

Mean 

percent

0.98

.82

.94

.77

.60

.46

.56

.50

.76

2.82

3.05

2.45

1.56

1.10

.86

.59

.46

.36

.34

.82

.29

.28

.32

.25

.21

.23

.21

.21

.21

.24

.20

Monthly load (tons)..

Tons per 

day

96,800

93,400

93, 700

70, 100

50,400

44,400

55,000

47, 700

68,300

258,000

264,000

210. 000

131, 000

91,800

67,800

45,900

35,000

28,300

25, 300

24,100

20,700

20,100

24,400

18,700

16,100

17,800

17,000

16,600

16,700

18,800

15,800

2, 004, 000

November

Mean 

discharge 

(secondfeet)

3,020

3.070

3,080

3,040

3,080

3,090

3,010

3,080

3,050

3,050

3,020

2,970

3,060

3,140

3,270

3,390

3,360

3,610

3,700

3,910

4,160

4,090

3,940

3,970

4,190

4,120

4,280

4,190

4,310

4,310

Suspended matter

Mean 

percent

0.22

.21

.21

. 99&&

.20

.21

.17

.18

.24

.22

.20

.23

.19

.18

.19

.18

.18

.20

.22

.20

.34

.29

.25

.26

.26

.23

.32

.25

.24

.26

Tons per 

day

17,900

17,400

17, 500

18, 100

16,600

17,500

13,800

15,000

19, 800

18, 100

16, 300

18.400

15, 700

15, 300

16, 800

16, 500

16, 300

19,500

22,000

21,100

38,200

32,000

26,600

27,900

29, 400

25, 600

37, 000

28,300

27, 900

30, 300

652,800

December

Mean 

discharge 

(secondfeet)

4,310

4,340

4,400

4,430

4,310

4,370

4,430

4,370

4,190

4,160

3,970

3,730

3,580-

3,640

3,640

3,880

4,370

4,120

4,430

4,590

4,970

5,100

4,940

5,000

5,160

5,200

4,940

4,780

4,750

4,810

4,840

Suspended matter

Mean 

percent

0.27

.31

.30

.28

.27

.26

.28

.26

.25

.26

.26

1.01

.24

.22

.24

.26

.78

.46

.29

.26

.26

.26

.25

.25

.26

.31

.27

.28

.27

.28

.25

Tons per 

day

31,400

36, 300

35,600

33,500

31,400

3Q, 700

33,500

30, 700

28,300

29,200

27,900

24,200

23,200

21,600

23,600

27,200

119,000

51,100

34,700

32,200

34,900

35,800

33,300

33,800

36,200

43,500

36,000

36, 100

34,600

36,400

32,700

1, 099, 000

1935

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....

January

4,940

4,970

4,880

4,880

4,940

5,130

5,320

4,970

4,840

4,880

4,650

5,130

5,260

5,000

6,060

7,450

7,560

6,590

6,160

6,790

6,760

6,430

6,000

5,550

5,420

4,940

4,530

4,000

3,530

3,380

3,540

0.27

.26

.23

.22

.22

.22

.26

.23

.20

.20

.17

.16

.20

.18

.28

.64

1.82

1.17

1.26

.76

2.12

1.47

.92

.84

.75

.60

.58

.65

.60

.56

.45

Monthly load (tons)..

36,000

34,900

30, 300

29, 000

29, 300

30,500

37,300

30,800

26,100

26,400

21, 300

22,200

28,400

24,300

45,800

129,000

371,000

208,000

210, 000

139, 000

387, 000

255, 000

149, 000

126,000

110,000

80,000

70,900

70,200

57,200

51, 100

43, 000

2, 909, 000

February

2,890

3,030

2,760

5,390

5,420

5,430

4,360

4,650

3,610

152

171

508

540

2,310

3,090

3,220

4,440

4,420

4,430

4,440

3,840

5,380

5,250

5,310

5,310

5,230

5,370

6,000

0.32

.12

.06

.10

.07

.07

.06

.05

.04

.02

.02

.02

.02

.04

.04

.09

.04

.04

.08

.23

.08

.08

.24

.17

.07

.07

.06

.08

25, 000

14, 700

4,210

14,600

10, 200

. 10, 300

7,070

6,260

3,890

81

92

275

297

2,480

3,350

7,830

4,780

4,780

9,560

27,600

8,290

11,600

34,000

24,400

10,000

9,880

8,690

13,000

277, 200

March

6,910

6,990

7,070

6,980

6,460

5,860

5,950

6,770

7,070

7,030

7,070

6,980

6,950

6,970

6,860

6,940

7,010

7,020

7,150

7,150

7,250

7,280

7,190

7,250

7,220

7,380

7,380

7,350

7,420

7,760

7,720

0.09

.10

.10

.07

.07

.05

.05

.06

.08

.06

.06

.06

.06

.06

.06

.05

.05

.05

.06

.03

.04

.05

.04

.06

.16

.52

.41

.34

.18

.30

.31

16,800

18,900

19,100

13,200

12, 300

7,910

8,050

11,000

15,300

11,400

11,400

11,300

11,300

11,300

11, 100

9,370

9,450

9,480

11,600

5,780

7,860

9,830

7,780

11,700

31,200

103,000

81,700

67,500

36,100

62,900

64,600

720,200
84 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 11. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Willow Beach, 

Ariz., Oct. 1, 1934, to Sept. 30, 1936 Continued

1935

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

Mean 

discharge 

(secondfeet)

7,720

7,690

7,620

7.650

7,550

7,380

7, 350

7,420

7,320

6,710

6,740

7,450

7,380

7,450

7,420

6,860

6,800

6,830

7,090

7,320

7,280

7,520

7,380

7,220

7,280

7,420

7.250

7,380

7, 150

7,280

Suspended matter

Mean 

percent

0.07

.06

.06

.06

.07

.07

.14

.32

00

. GO

.53

.95

.70

.72

.95

.81

1.15

.96

.62

.45

.24

.31

.04

.04

.05

.04

.40

.08

.05

.05

.06

Monthly load (tons) . -

Tons per 

day

14, 600

12, 400

12, 300

12, 400

14, 300

14. 000

27, 800

64, 100

75, 100

95, 900

173, 000

141, 000

143, 000

191, 000

162, 000

213, 000

176, 000

114, 000

86, 100

47, 400

60, 700

8,120

7,960

9. 750

7,860

80, 100

15, 700

9,960

9,670

11, 800

2, Oil, 000

May

Mean 

discharge 

(secondfeet)

f., 470

7,220

7,350

7,650

7,720

7,690

7,350

7,320

7,420

7,120

6,860

7,320

6,830

6,520

6,610

6,550

6,610

7.070

7,350

7,220

6,930

7,910

11, 300

13, 000

14, 800

14, 700

15, 000

14, 900

14, 900

15, 200

15, 000

Suspended matter

Mean 

percent

0.04

.04

.03

.03

.03

.03

.05

.04

.04

.04

.05

.05

.07

.10

.06

.06

.06

.07

.05

.05

.04

.06

.08

.07

.08

.08

.09

.09

.06

.07

.06

Tons per 

day

6,990

7,800

5,940

6,210

6,260

6,240

9,940

7,910

8,020

7,690

9,260

9,880

12, 900

17, 600

10, 700

10, 600

10, 700

13, 400

9,940

9,750

7,480

12, 800

24, 400

24, 600

32, 000

31, 800

36, 400

36, 200

24, 100

28, 700

24, 300

470, 600

June

Mean 

discharge 

(secondfeet)

15, 200

15, 300

15, 300

15, 800

15, 800

15, 900

16, 300

16, 300

16,200

16, 400

16, 800

17, 000

17, 200

17, 300

17, 300

17, 600

17, 800

18, 000

18, 400

18, 500

18, 600

18, 900

19, 100

16, 800

14, 400

14, 500

14, 800

14, 700

14, 700

15, 100

Suspended matter

Mean 

percent

0.06

.06

.04

.07

.06

.05

.05

.05

.04

.06

.05

.06

.05

.04

.04

.04

.04

.06

.04

.04

.05

.04

.04

.04

.04

.05

.05

.05

.04

.07

Tons per 

day

24,600

24, 800

16, 500

29,900

25, 600

21, 500

22, UOO

22, 000

17,500

26, 600

22, 700

27, 500

23, 200

18, 700

18, 700

19, 000

19,200

29,200

19, 900

20, 000

25, 100

20, 400

20, 600

18,100

15,600

19, 600

20,000

19, 800

15, 900

28, 500

652, 700

1935

1-.--.

2--___

3-....

4...-.

5--.-

6--.-

7.-.--

8----_

9---..

10--_-

11-.-.

12-..-

13_--.

l4-.-_

15---.

16--.-

17.-..

18--..

19.-..

20-.-.

21..-.

22....

23...-

24---.

25-.-_

26....

27---.

28---

29---_

30----

31--..

July

15, 000

15, 000

15. 000

15, 000

15, 000

15, 300

15, 200

15, 000

13, 300

10,000

10,200

10, 100

10,200

10, 000

9,960

10,200

10, 100

9,960

10,000

10,000

10, 000

10, 100

10, 300

10,200

9,960

10,000

10, 100

10, 000

10, 100

10,200

10,100

0.04

.05

.06

.07

.04

.05

.08

.04

.05

.04

.04

.03

.03

.02

.03

.04

.01

.01

.03

.02

.04

.04

.04

.04

.03

.03

.03

.02

.02

.03

.03

Monthly load (tons)..

16, 200

20, 200

24, 300

28, 300

16.200

20, 700

32, 800

16, 200

18, 000

10, 800

11, 000

8,180

8,260

5, 400

8,070

11, 000

2,730

2,000

8,100

5,400

10. 800

10, 900

11, 100

11, 000

8.080

8,100

8.180

5,400

5,450

8,260

8,180

369, 300

August

10, 100

10, 200

10, 500

10, 000

10, 200

10, 200

10,200

10,200

10,200

10, 300

10, 100

10, 200

10, 200

10, 000

10, 300

10,200

10, 400

10,200

10, 200

10, 300

10, 000

10, 200

10, 200

10, 200

10, 100

10,200

10, 000

9,840

10,100

10, 400

10, 200

0.04

.03

. .05

.03

.04

.04

.05

.04

.05

.04

.07

.05

.04

.04

.01

.02

.02

.03

.02

.03

.02

.03

.04

.02

.02

.02

.02

.04

.02

.02

.02

......-..-

10, 900

8,260

14, 200

8,100

11, 000

11, 000

13, 800

11. 000

13, 800

11, 100

19, 100

13, 800

11, 000

10, 800

2,780

5,510

5,620

8,260

5,510

8,340

5,400

8,260

11,000

5,510

5,450

5,510

5,400

10, 600

5,050

5,620

5,510

277, 200

September

10, 100

10, 000

9,960

10, 100

9,960

10, 100

10, 000

10, 100

9,960

10, 000

10, 000

10, 100

10. 000

9,920

10, 100

10, 100

9,960

9,960

10, 000

10, 000

10, 100

9,960

9,920

9,840

9,920

10,100

9,800

9,880

9,920

9,800

_ _ --_ __ __

0.03

.02

.86

.99

.68

.17

.42

.94

.70

.57

1.08

1.37

.71

.27

.01

.03

.01

.02

.01

.01

.01

.03

.01

.01

.01

.01

.01

.01

.02

.01

----------

8,180

5,400

231,000

270,000

183, 000

46, 400

113, 000

256, 000

188, 000

154, 000

292, 000

374, 000

192, 000

72, 300

2,730

8,180

2,700

5,370

2,700

2,700

2,730

8,070

2,670

2,650

2,670

2,730

2,650

2,670

5,350

2,650

2, 444, 000
QUANTITIES OF SUSPENDED SEDIMENT 85

TABLE 11. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Willow Beach, 

Ariz., Oct. 1, 1934, to Sept. 30, 1936 Continued

1935

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 

:

October

Mean 

discharge 

(secondfeet)

9,940 

9,860 

10, 000 

9,960 

9,980

9,740 

9,720 

9,880 

9,800 

9,680

9,900 

10, 000 

9,720 

9,860 

9,760

9,840 

9,820 

9,840 

9,860 

9,900

9,900 

9,760 

9,740 

9,760 

9,800

9,780 

9,780 

9,800 

9,800 

9,760 

9,900

Monthly loa

Suspended matter

Mean 

percent

0.005 

.007 

.02 

.007 

.01

1.57 

1.60 

1.64 

1.99 

2.16

1.86 

1.19 

.34 

.004 

.002

.005 

.009 

.003 

.02 

.02

.02 

.02 

.01 

.01 

.01

.01 

. .01 

.02 

.02 

.02 

.01 

d (tons)-

Tons per 

day

1,350 

1,860 

5,400 

1,890 

2,700

413, 000 

420, 000 

437. 000 

526, 000 

565, 000

497, 000 

321, 000 

89,200 

1,050 

540

1,320 

2,380 

810 

5,320 

5,350

5,350 

5,260 

2,620 

2,650 

2,650

2,650 

2,650 

5,290 

5,290 

5,260 

2,670

3, 340, 000

November

Mean 

discharge 

(secondfeet)

9,880 

9,760 

9,680 

9,800 

9,740

9, 680 

9,740 

9,840 

9,620 

9,620

9,700 

9,640 

9,680 

9,740 

9,740

9,660 

9,720 

9,800 

9,620 

9,600

9,620 

9,640 

9,740 

9,780 

9,640

9,560 

9,760 

9,520 

9,480 

7,470

Suspended matter

Mean 

percent

0.04 

.04 

.04 

.04 

.04

.05 

.04 

.03 

.04 

.04

.04 

.04 

.04 

.04 

.05

.04 

.04 

.03 

.03 

.03

.03 

.03 

.03 

.04 

.03

.04 

.04 

.04 

.03 

.03

Tons per 

day

10, 700 

10, 500 

10,400 

10, 600 

10,500

13, 100 

10, 500 

7,960 

10,400 

10, 400

10, 500 

10, 400 

10, 400 

10, 500 

13, 100

10,400 

10, 500 

7,940 

7,800 

7,780

7,800 

7,800 

7,880 

10, 600 

7,800

10, 300 

10, 500 

10, 300 

7,670 

6,050

291, 100

December

Mean 

discharge 

(secondfeet)

4,950 

4,950 

4,920 

4,910 

4,890

4,910 

4,920 

4,940 

4,950 

4,870

4,870 

4,860 

4,890 

4,920 

4,920

4,940 

4,810 

4,920 

4,860 

4,810

4,760 

4,790 

4,830 

4,860 

4,870

4,890 

4,760 

4,870 

4,810 

4,830 

4,870

Suspended matter

Mean 

percent

0.006 

.006

.005 

.002

.007

.01 

.01

.008

.006

.004 

.005 

.01 

.01

.01

.004 

.01

.005 

.004 

.009 

.005 

.006 

.006

Tons per 

day

810 

810

675 

270

918

1,350 

1,320

1,050

810

540 

648 

1,320 

1,320

1,300

513 

1,320

648 

513 

1,190 

648 

783 

783

1936

1. 

2..___

3_ 

4 .

*...-

6. 

7. 

8. 

9 

10 

lllS. 

13. 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25....

26. 

27 

28 

29 

30 

31 

January

4,810

4,870

4,860

4,790

4,920

4,940

4,860

4,860

4,810

4,860

4,840

4,830

4,910

4,830

4,890

4,760

4,860

4,810

4,870

4,840

4,790

4,890

4,790

4,810

4,750

4,860

4,830

4,840

4,810

4,810

4,860

0.01

.01

.01

.007

.005

.002

.004

.006

.006

.007

.004

.009

.004

.004

.005

.02

.006

.004

.009

.008

.007

.008

.004

.003

.004

.004

. 007

.004

.004

.004

.002

Monthly load (tons) 

1,300

1,320

1,320

918

675

270

513

783

783

918

513

1,160

540

513

648

2,560

783

513

1,190

1,050

918

1,050

513

378

513

513

918

513

513

513

270

24,880

February

4,840

4,890

4,810

4,810

4,810

4,760

4,870

4,790

4,890

4,870

5,120

6; 180

6,060

6,110

fi DT fl40 u^tu

6,500

6,500

6,570

6,320

6,180

6,130

5,940

5,860

5,960

5,960

5,860

5,960

6,130

6,400

0.005

.004

.006

.005

.005

.006

.004

.004

.006

.005

.003

.01

.009

.004

.005

.006

.008

.004

.006

.008

.005

.003

.01

.006

.006

.006

.007

.01

.01

648

540

783

648

648

783

' 513

513

783

648

405

1,670

1,480

648

Qin oiu

1,050

1,400

702

1,030

1,320

837

486

1,590

972

972

945

1,130

1,650

1,730

27, 330

March

6,370

6,380

6,620

6,910

7,320

7,830

8,770

8,810

9,190

9,580

9,520

9,700

9,760

9,740

9,680

9,640

9,680

9,780

9,780

9,820

9,860

9,820

9,820

9,780

9,680

9,700

9,600

9,740

9,780

9,780

9,720

0.006

.01

.009

.009

.01

.01

.02

.02

.02

.02

.02

.02

.02

.02

.03 .-02

.03

 .03

.02

.02

.03

.02

.03

.02

.02

.02

.02

.03

.02

.02

1,030

1,730

1,620

1,670

1,970

2,110

4,720

4,750

4,970

_ 5, 180

5,130

5,240

5,260

5,260

7,800

5,240

7,910

7,910

5,290

5,320

7,960

5,290

7,910

5,240

5,240

5,180

5,260

7,910

5,290

5,240

155, 900
86 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 11. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Willow Beach, 

Ariz., Oct. 1, 1934, to Sept. 30, 1936 Continued

1936

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

Mean 

discharge 

(secondfeet)

9,740

9,780

9,560

9,760

9,700

9,560

9,900

9,740

9,600

9,720

9,660

9,480

9,700

9,740

9,680

9,740

9,760

9,760

9,820

9,860

9,680

9,840

9,740

9,860

9.960

10,200

10,200

10, 700

11, 100

10, 900

Suspended matter

Mean 

percent

0.02

.02

.02

.02

.02

.02

.02

.02

.01

.02

.02

.01

.01

.01

.02

.01

.01

.01

.04

.02

.02

.21

1.16

1.31

1.41

1.44

1.12

.74

.71

.77

Monthly load (tons) - -

Tons per 

day

5,260

5,290

5,160

5,260

5,240

5,160

5,350

5,260

2,590

5,240

5,210

2,560

2,620

2,620

5,240

2,620

2,650

2,650

10,600

5,320

5,240

55, 800

305, 000

349, 000

379, 000

397, 000

308, 000

214, 000

213, 000

2, 545, 000

May

Mean 

discharge 

(secondfeet)

9,460

9,220

10, 100

10,200

10,300

10,000

9 Qsn

10,100

9,890

8,840

9,150

9,580

9,310

8,620

8,670

8.650

8,840

9,070

8,130

7,900

8,010

8,030

8,010

8,300

8,600

9,110

9,440

10,200

Suspended matter

Mean 

percent

0.10

.03

.02

.02

.02

.02

.02

.02

.01

.01

.01

.01

.005

.01

.008

.01

.008

.007

.008

.02

.008

.01

.01

.009

.008

.007

.01

.01

.01

.01

Tons per 

day

25,500

7,480

5,450

5, 560

5,510

5,560

5,400

5,400

2,730

2,730

2,670

2,380

- 1,240

2,590

2,000

2,320

1,860

1,650

1,920

4,890

1,760

2,130

2,160

1,940

1,730

1,570

2,320

2,460

2,540

2,750

117, 800

June

Mean 

discharge 

(secondfeet)

9,880

9,860

9,700

9,900

10,000

9,840

9,420

9,440

9,500

9,190

9,130

8,780

8,840

9.660

9,760

9,780

9,960

10,800

10, 500

10, 700

10,800

10,900

11,200

11,200

11, 400

11,400

11,500

11, 500"

11, 700

11, 500

Suspended matter

Mean 

percent

0.02

.01

.01

.01

.01

.01

.02

.01

.01

.02

.01

.01

.01

.008

.01

.01

.01

.01

.02

.01

.01

.01

.009

.008

.01

.01

.01

.01

.01

.01

Tons per 

day

5,350

2,670

2,620

2,670

2,700

2,650

5,080

2,540

2,560

4,970

2,460

2,380

2,380

2,080

2,650

2,650

2,700

2,920

5,670

2,890

2,920

2,940

2,730

2,430

3,080

3,080

3,100

3,100

3,160

3,100

92, 230

1936

July

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...-

11, 400

11,500

11, 600

11, 500

11, 500

11, 300

11, 400

11, 500

11, 500

11,500

11, 400

11, 400

11, 400

11,400

11,500

11,300

11,500

11,400

11, 300

11,400

11, 300

11,200

11,000

11,100

11, 100

11,200

11, 100

11,000

11,200

11,000

11, 100

0.02

.01

.01

.01

.009

.01

.02

.01

.01

.01

.02

.01

.01

.008

.01

.01

.009

.008

.008

.008

.01

.007

.005

.009

.008

.01

.009

.02

.008

.007

.01

Monthly load (tons).

6,160

3,100

3,130

3, .100

2,810

3,050

6,160'

3,100

3,100

3,100

6,160

3,080

3,080

2,460

3,100

3,050

2,810

2,460

2,430

2,460

3,050

2,110

1,480

2,700

2,400

3,020

2,700

5,940

2,430

2,080

3, 000

98, 810

August

11, 000

11, 100

10, 900

10, 600

10,600

10, 500

10, 400

10, 600

10,500

10,200

9,880

9,760

9,760

9,740

9,680

9,640

9,640

9,680

9,600

9,720

9,760

9,700

9,600

9,580

9,220

9,500

9,500

9,680

9,660

9,540

9,560

0.007

.008

.009

.03

.009

.02

.007

.008

.006

.006

.009

.01

.009

.005

.006

.006

.005

.005

.004

.009

.005

.006

.005

.003

.003

.006

.001

.002

.009

.003

.003

2,080

2,400

2,650

8,590

2,560

5,670

1,970

2,300

1,700

1,650

2,400

2,650

2,380

1,320

1,570

1,570

1,300

1,300

1,030

2,350

1,320

1,570

1,300

783

756

1,540

270

513

2,350

783

783

61, 410

September

9.580

9,600

9,580

9,640

9,780

9,620

9,540

10, 000

9,520

9,640

9,920

9,600

9,660

9,700

10,000

9,640

9,620

9,460

9,520

9,720

9,150

9,030

9,020

8,900

8,810

8,750

8,500

8,310

8,300

8,130

0.006

.006

.01

.008

.01

.01

.01

.02

.007

.01

.006

.006

.005

.004

.006

.003

.006

.003

.005

.01

.006

.008

.002

.005

.008.

.005

.005

.003

.007

.005

1,540

1,570

2,590

2,080

2,650

2,590

2,560

5,400

1,810

2,590

1,620

1,570

1,300

1,050

1,620

783

1,570

756

1,300

2,620

1,480

1,940

486

1,190

1,890

1,190

1,130

675

1,570

1,110

52,230
QUANTITIES OF SUSPENDED SEDIMENT 87

TABLE 12. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Topock, Ariz., Oct. 1, 1925, to Sept. SO, 1984

1925-26

Day

1 .

2 .

3... .

4 

5 .

6

7 .

8 

9 

10 

11 

12...

13 

14 

15...

16

17

18...

19

*

21 

22...

23 

24...

flfi

26 

27

28- .

 29 

30

31

October

1.31

.87

1.40

3.56

2.61

1.56

1.16

.92

.56

November

0.71

.47

.51

.40

.51

.49

34

.27

December

0.28

.42

.36

.32

.20

.32

.25

January

0.29

.20

.29

.34

.25

.29

.25

.26

February

0.31

.26

.21

.22

.14

13

.20

.31

March

6.19

.20

.17

.21

.34

.28

.54

.58

April

0.54

.70

.64

.94

1.28

1.10

1.10

1.00

May

1.06

.69

.88

.77

.72

.67

.61

.35

June

0.76

.62

.44

.49

.54

.64

.28

July

0.45

.37

.34

.39

.51

1.14

"1.30

.53

August

0.37

.37

.53

.45

. .73

.96

.75

.55

.72

September

0.56

.53

.35

.56

48

2.17

1.86

1926-27

1 

3

4 ...

5 ..

6 ..

*t

8... .

9.....

10 

11 

12 

13 

14 

15 

16...

 17...

18...

19 

20 

21 

22 

23...

24 

25 

26 

27...

28 

29 

30...

31 

2.03

5.74

2.27

2.20

1.18

1.01

.84

.74

.53

0.42

.28

.24

.29

.23

.24

.26

.27

.43

0.22

.37

.36

.34

.42

.63

.27

.26

.26

0.15

.16

.20

.17

.18

n 13

.14

.12

.15

30

.42

.47

1.80

0.76

.66

.77

.64

.58

.39

.36

.45

0.44

.78

1.10

1.16

1.29

1.23

1.31

1.13

Ofi

1.22

79

on

0.96

.82

.89

1.34

.86

1.13

.79

.65

1.18

1.37

1.18

.69

.66

.64

.72

.72

72

2.11

1.75

1.10

.79

1.63

1.44

.60

.96

.82

0.91

1.37

1.18

1.34

2.37

2.11

1.16

.72

1.76

1.71

2.39

1.81

4.39

*7.91

5.30

3.36

2.02
SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 12. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Topock', Ariz., Oct. 1, 1925, to Sept. 80, 1934 Continued

1927-28

Day

1 

2 

3 

5 

6_ 

7 

8 

9_ 

10 

11 

12.. _

10

14 

15 

16

17 

18 

19

on

21 

99

23 

24 

25 

?6

27 

28 

29 

30

31

October

1.09

1.30

1.06

.72

.43

.42

.50

.61

.35

November

i. 12

1.63

.67

.95

.87

.98

.85

.29

.20

December

0.21

.53

.21

.34

.24

.32

.26

.64

January

0.75

1.03

.74

.19

.36

.41

.32

.29

February

0.70

.41

.40

.47

.74

.36

.28

.26

March

0.48

.41

.21

.34

__ .46

.45

.34

.43

.78

April

0.83

2.08

1.02

.56

.78

.64

.69

.94

May

0.55

.77

1.17

1.20

.72

1.63

1.85

2.40

1.03

June

0.89

.81

1.14

3.01

1.33

1.60

.94

.97

.84

July

0.64

.58

.98

.63

.52

.51

.65

1.20

1.22

August

0.83

.76

.76

1. 16

.53

.49

.80

.55

.74

September

0 48

1.25

1.06

.71

.64

00

.42

.34

1928-29

5 

6

7 

8 _

9__ _

10 

11 ..

10

15 

16. _'

17 

18 

19 

9!0

21 

99

23 

24 

25 

26

27 

?8

29

30

31

0.29

.30

.25

1.21

2.57

1.86

1.08

1.04

1.10

.88

1.35

1.20

1.18

.64

.68

0.49

.48

.64

.42

.54

.40

.41

.47

.31

.36

.36

0.59

.47

.45

.46

.48

w

w

0.38

.29

.62

.35

.56

.50

.40

.36

0.28

.38

.38

.55

.98

2.42

1.89

1.60

1.91

1.39

1.44

2.82

2.02

1.61

1.46

1.14

1.56

1.19

1.26

1.22

1.09

1.07

.88

.68

.98

.86

1.55

.93

.69

1.12

.82

.83

1.82

0.90

.83

.82

1.02

.52

.59

1.10

1.35

5.46

4.48

4.52

4.16

6.66

5.19

1.03

1.02

3.08

._ 3.14

3.68

2.36

i.44

1.34

6.18
QUANTITIES OF SUSPENDED SEDIMENT 89

TABLE 12. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Topock, Ariz., Oct. 1, 1925, to Sept. SO, 1934 Continued

1929-30

Day

1

9, }

4

5

6

7

8

9

10

11 

1?

13

14

IS

16

17

18

1990

21...

9,?: 93

94

95

26

97

28

9fl

30

31

October

2.92

1.84

1.18

1.04

.84

.94

1.18

1.18

November

0.75

.68

.98

.89

.90

.80

.87

.71

December

0.39

.77

.73

.81

.52

.42

.43

.52

January

0.33

.39

.56

.46

.42

.28

.26

February

0.38

.56

.46

.36

.32

.36

.76

March

0.77

.62

.66

.48

.60

.44

.59

.66

April

0.89

.87

.71

.72

1.13

1.24

1.16

1.23

May

1.16

1.33

1.15

.96

1.15

.90

.84

.70

.85

June

0.92

.92

1.02

.82

.80

.70

.76

.90

1.10

.75

.69

July

0.58

.41

.49

.58

.42

.48

.62

1.58

2.60

3.04

3.01

2.14

August

3.08

2.70

6.71

6.35

5.86

3.17

2.04

1.52

September

1.11

84

.98

1.20

1.40

1.13

.97

.62

1930-31

1

9,

3

4

5

6

7

8

9

10

1119

13

14 

15

16

17

18

19

90

91

??.

93

24

?5

96

97

98

9fl

30

31

0.64

.75

.95

1.41

1.04

1.08

.66

.60

0.76

.48

.53

.54

.86

.76

.69

.52

0.42

.48

.55

.82

.56

.47

.40

.54

0.28

- .30

.41

.38

.44

.29

.26

.26

0.34

.28

.28

.28

.44

1.08

.86

0.48

.44

.47

.46

.42

.35

.40

.44

0.56

.56

.40

.75

.50

.39

.60

.62

0.66

.52

.84

.66

.76

.54

.94

.85

0.75

.74

.70

.59

.72

.70

.54

.59

.51

0.50'

.41

.94

1.00

.36

.20

.18

1.56

.68

2.49

2.97

1.75

1.20

1.61

0.99

1.00

1.56

.96

.76

.62

1.14

.90
90 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 12. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Topock, Ariz., Oct. 1, 1925, to Sept. 30, 1934 Continued

1931-32

Day

1

3

4

fi

6

7

8

9

10

11

1?

13

14

IS

1R

17

18

19

on

21

99

?,3

?4

25...

?fi

W >8

90

 ¥»

31

October

3.76

2.52

2.72

2.28

1.62

1.26

1.25

1.08

November

1.75

1.09

.68

.64

.80

2.40

2.08

1.21

1.35

December

0.78

.68

.91

.84

.58

.37

-

.36

.76

January

0.75

.79

.62

.68

.47

.30

.50

.31

.28

February

0.26

.28

.35

2.82

3.18

2.03

1.56

1.36

March

1.58

1.54

1.84

1.86

1.54

1.14

1.18

1.46

1.68

April

.

1.50

1.30

1.52

1.79

1.96

1.46

1.30

1.74

1.66

May

1.44

,

1.31

1.14

1.12

.90

.68

.76

.74

.80

June

1.36

1.28

.98

1.08

.85

.70

.74

.62

July

0.58

.67

.75

.80

.78

2.62

1.17

.96

.63

August

0.54

1.05

1.52

.82

.47

.39

.39

.46

4.35

September

6.50

4.48

2.88

1.65

1.25

.82

.50

.60

1932-33

fi

6

7

8

9

10

12...

13

14

15

16

18

19

?,0

?1

23

?4

?5

?6

?,7

?8

?9

30

31

0.52

.87

1.36

1.66

.73

.55

.77

.41

0.72

.54

.47

.J2

.40

.44

.36

.40

.54

0.44

.43

.36

.24

.26

.32

0.34

.25

.41

.22

.36

.32

.28

.40

0.34

.40

.40

.29

.44

30

.29

.27

0.58

.30

.58

.40

.54

.44

.54

.47

0.46

.44

.40

.40

.50

.33

.26

.28

0.36

.28

.71

.88

.91

.76

.59

1.12

1.14

0.90

.88

.77

.68

.70

.70

1.18

1.23

0.92

.68

.72

.78

2.41

1.88

1.29

1.51

1.10

.78

1.68

1.04

.76

.94

1.68

2.28

.76-

0.80

.96

.68

.72

1.15

5.28

3.40

1.57
QUANTITIES OF SUSPENDED SEDIMENT 91

TABLE 12. Mean daily concentration of suspended sediment in the Colorado River 

at gaging station near Topock, Ariz., Oct. 1, 1925, to Sept. SO, 1934 Continued

1933-34

Day

1

2 

3

4

fi

6

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

?,1

?,?,

?,3

?4

?,5

?,6

27

28

?fl

30

31

October

1.66

1.05

.91

4.27

3.90

1.51

1.40

.36

1.28

1.04

November

0.54

.43

.45

.42

.54

.56

December

0.55

1.16

.59

.76

.79

.48

.46

.50

.40

January

0.52

.84

.56

.48

.53

.30

.40

.30

.30

February

0.32

.47

.28

.26

.36

.28

.24

.28

March

0.31

.24

97

.27

.35

.32

OK

.21

.20

April

0.38

.18

.18

.18

.26

.26

^Q

May

0.60

.64

.74

.65

.83

.87

.85

79

.72

June

0.72

1.64

.96

.!>2

.99

.26

.27

.24

.20

.15

July

0.15

.14

.13

.16

.14

.17

.12

.17

.22

.18

.18

.15

.20

.15

.20

.16

.15

.14

.14

.14

.15

.15

.18

10

.16

.18

.12

.12

.06

.12

.18

August

0.22

.22

.17

.22

.67

.22

.18

.14

.25

.48

.36

.24

.22

.29

.28

.78

.74

.64

.32

.44

.90

.93

.76

1.12

.58

.32

.49

1.54

.78

.96

September

0.92

1.48

1.93

2.20

2.28

3.93

4.78

4.20

7.87

4.46

3.36

4 14

4.50

4.58

4.81

5.10

5.04

4.42

4.04

3.70

3.11

2.59

2.28

2.17

1.84

1.68

1.32

1.20

.77

60

725606 47-
92 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 13. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Topock, Ariz., 

Oct. 1, 1934, to Mar. 31, 1939

1934

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....

October

Mean 

discharge 

(secondfeet)

1,760

1,780

3, J>20

3,690

3,200

2,990

2,900

3,320

3,480

3,200

3,110

2,990

2,870

2,840

2,760

2,730

2,590

2,450

2,620

2,540

2,590

2,420

2,300

2,450

2,510

2,480

2,560

2.640

2,640

2,730

2,730

Suspended sediment

Mean 

- percent

0.55

.71

1.87

1.10

.90

.89

.74

.72

.73

.65

.53

1.64

2.60

2.65

1.93

1.33

.97

.74

.69

.54

.46

.44

.43

.51

.48

.44

.43

.43

.42

.44

.40

Total load (tons) ......

Tons per 

day

26,100

34,100

193, 000

110,000

77,800

71, 800

57, 900

64,500

68,600

56, 200

44,500

132, 000

202,000

203,000

144, 000

98,000

67,800

49,000

48,800

37,000

32,200

28,800

26, 700

33, 800

32,500

29,500

29,700

30,600

29 900

32^ 400

29,500

2, 122, 000

November

Mean 

discharge 

(secondfeet)

;c,620

2,700

2,790

2,820

2.870

2,870

2,840

2,820

2,840

2,840

2,900

2,900

2,730

2,760

2,840

2,960

3,110

3,140

3,110

3,260

3,510

3,910

4,040

3,940

3,790

3,790

3,940

4,070

4,130

4,010

Suspended sediment

Mean 

percent

0.36

.34

.37

.39

.37

.36

.32

.33

.32

.29

.29

.29

.26

.36

.34

.28

.30

.36

.34

.34

.46

.48

.47

.52

.48

.42

.44

.55

.48

.45

Tons per 

day

25,500

24,800

27,900

29,700

28,700

27, 900

24,500

25, 100

24, 500

22,200

22,700

22,700

19,200

26,800

26, 100

22,400

25,200

30,500

28,500

29,900

43,600

50,700

51,300

55, 300

49, 100

43,200

46,800

60,400

53,500

48,700

1,017,000

December

Mean 

discharge 

(secondfeet)

4,010

4,010

4,040

4,130

4,290

4,040

4,130

4,070

3,970

3,940

3,970

3,880

3,940

3,6oO

3,720

3,480

3,410

4,210

3,880

3,940

4,200

4,590

4,700

4,730

4,630

4,830

4,900

4,940

4,870

4,590

4,300

Suspended sediment

Mean 

percent

0.46

.54

.53

.48

.59

.47

.51

.45

.60

.46

.43

.43

.42

.34

.39

.34

.37

.80

.68

.56

.50

.54

.54

.60

.44

.35

.43

.40

.34

.33

.56

Tons per 

day

49,800

58,500

57,800

53,500

66,900

51,300

56,900

49,500

64,300

48,900

46,100

45,000

44,700

33,000

39,200

31,900

34,100

90,900

71,200

59,500

56,700

67,000

68,500

76,600

55,000

45,600

56,900

53,400

44,700

40,900

65,000

1, 683, 000

1935

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....

January

4,330

4.660

4,760

4.730

4,590

4,760

4,760

4,800

4,830

' 4,760

4,490

4,630

4,330

4,970

4,bOO

5,110

6,210

7,780

6,390

6,280

6,280

6,360

6,100

5,800

5,500

5,200

4,900

4,700

4,010

3,690

3,470

0.56

.51

.54

.56

.55

.46

.45

.52

.42

.41

.52

.47

.36

.42

.54

.56

.68

.95

1.88

1.24

1.77

1.14

2.64

1.62

.96

.98

.88

.73

.62

.68

.63

Total load (tons).. .

65,500

64,200

69,400

71, 500

68,200

59, 100

57,800

67,400

54,800

52,700

63,100

58, 800

42,100

56,400

70,000

77,300

114, 000

200,000

324,000

210,000

300, 000

196, 000

435, 000

254,000

143,000

138,000

116,000

92,600

67,100

67,800

59,000

3,715.000

February

3,420

3,210

2,570

3,210

4,170

5,830

5,590

4,690

4,790

4,320

1,690

900

570

422

747

2,670

2,840

3,580

4,000

4,080

4,200

3,950

4,420

4,890

4,800

4,800

4,810

4,840

-0.66

.54

.36

.40

.58

.47

.38

.36

.51

.36

.14

.04

.02

.02

.02

.25

.17

.33

.53

.38

.32

.40

.36

.37

.53

.52

.36

.34

-. ___ __ __ _ .

60,900

46,800

25,000

34,700

65,300

74,000

57,400

45,600

66,000

42,000

6,400

972

308

227

405

18,000

13,000

31, 900

57,200

41,900

36,300

42,700

43,000

48,800

68,700

67,400

46,300

44,400

1, 086, 000

March

5,270

6,150

7,120

7,040

6,780

6,510

5,610

5,580

6,000

6,620

6,700

6,800

6,890

6,720

6,550

6,690

6,540

6,430

6,540

7,060

6,760

7,060

7,140

7,020

7,060

6,950

7,060

7,020

6,800

6,840

7.250

0.37

.39

.40

.39

.35

.40

.32

.34

.36

.55

.44

.40

.42

.30

.38

.44

.38

.3^

.43

.30

.31

.33

.3C

.32

.27

.28

.57

.70

.57

.58

.54

52,700

64,800

76,900

74, 100

64,100

70,300

48,500

51,200

58,300

98,300

79,600

73,400

78,100

54,400

67,200

79,500

67,100

55.600

75,900

57,200

56,600

62,900

57,800

60,600

51,500

52,500

109,000

133,000

105,000

107,000

106,000

2, 249. 000
QUANTITIES OF SUSPENDED SEDIMENT 93

TABLE 13. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station -near Topock, Ariz., 

Oct. 1, 1934, to Mar. 31, 1939 Continued

1935

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

Mean 

discharge 

(secondfeet)

7,500

7,020

7,290

7,100

7,100

7,170

6,910

6,730

7,210

7,290

6,580

6,540

7,330

6,990

6,800

7,020

6,840

6,360

6,500

6,430

6,800

7,170

6,950

6,650

6,620

6,800

6,760

6,540

6,690

6,840

Suspended sediment

Mean 

percent

0.44

.35

.31

.32

.27

.30

.25

.25

.40

.46

.46

.66

.82

.77

.99

1.00

1.00

1.24

.91

.70

.60

.54

.42

.48

.30

.26

.26

.57

.26

.29

Total load (tons) __

Tons per 

day

89, 700

66,300

61, 000

61, 300

51,800

58,100

47,300

45,400

77,900

90,500

81, 700

117, 000

162,000

145, 000

182, 000

190, 000

185, 000

213, 000

160,000

122,000

110, 000

105,000

78,800

86,200

53,600

47,700

47,500

95, 300

47, 000

53,600

2, 932, 000

May

Mean 

discharge 

(secondfeet)

6,730

6,500

6,730

6,950

7,170

7,290

7,100

6,880

6,800

7,100

6,800

6,690

6,650

6,690

6,280

6,070

6,180

6,250

6,280

7,060

7,250

6,580

6,730

10,200

12,700

13,600

13, 700

14,000

14,000

14, 100

14,400

Suspended sediment

Mean 

percent

0.26

.25

.28

.26

.22

.24

.22

.21

.21

.20

.20

.19

.24

.27

.22

.19

.22

.27

.25

.24

.27

.20

.23

.40

.47

.45

.35

.38

.30

.38

.30

Tons per 

day

47,200

70, 900

50, 900

48,800

42,600

47,200

42,200

39, 000

38,600

38,300

36, 700

34, 300

43, 100

48,800

37, 300

31, 100

36,700

45,600

42,400

45,700

52, 900

35,700

41, 800

110, 000

161, 000

165, 000

129,000

143, 000

113,000

145, 000

117,000

2, 082, 000

June

Mean 

discharge 

(secondfeet)

14, 200

14,500

14, 700

15,000

15,300

15,500

15,300

15, 300

15,500

15,400

15,400

15, 900

15,100

16,200

16, 300

16, 300

16,600

16,900

17,000

17,200

17,600

17, 300

17,700

18,300

16,400

13,800

13, 700

13,800

13, 900

13, 900

Suspended sediment

Mean 

percent

0.32

.30

.28

.28

.29

.30

.26

.28

.29

.34

.24

.32

.28

.26

.32

.31

.28

.27

.28

.26

.28

.32

.32

.30

.24

.32

.23

.26

.26

.27

Tons per 

day

123,000

117, 000

111, 000

113, 000

120,000

126, 000

107,000

116,000

121,000

141, 000

99, 700

137, 000

114, 000

114,000

141, 000

136,000

125,000

123,000

129,000

121,000

133,000

149,000

153,000

148,000

106,000

119,000

85, 100

96,900

97,600

101,000

3, 623, 000

1935

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....

July

14,000

14,100

13,900

14, 100

13, 900

14,000

14, 100

13,600

14, 500

13,000

9,720

9,720

9,760

9,760

9,480

9,680

9,520

9,680

9,760

9,800

9,640

9,640

9,680

9,240

9,320

9,480

9,600

9,480

9,600

9,000

9,120

0.26

.29

.26

.36

.26

.26

.26

.24

.26

.26

.26

.18

.18

.17

.21

.23

.16

.19

.16

.20

.20

.21

.22

.23

.26

.26

.40

.23

.31

.24

.22

Total load (tons) __

98,300

110, 000

97. 600

137,000

97,600

98,300

100, 000

88,100

102, 000

91,300

68,200

47,200

47,400

44,800

53,800

60,100

41,100

49, 700

42,200

52, 900

52, 100

54,600

57, 500

57,400

65,400

66,600

104,000

58,900

80,400

58, 300

54,200

2, 237, 000

August

9,280

9,480

9,400

9,480

9,400

9,600

9,560

9,400

9,400

9,600

9,640

9,600

9,720

9,560

9,520

9,360

9,680

9,720

9,360

9,320

9,400

9,360

9,400

9,640

9,640

9,560

9,640

9,560

9,480

9,280

9,560

0.18

.20

.21

.22

.16

.16

.28

.39

.20

.16

.21

.22

.17

.22

.25

.17

.19

.23

.24

.18

.20

.25

.15

.14 .16'

.15

.15

.15

.19

.13

.14

45,100

51,200

53, 300

56,300

40,600

41,500

72,300

99, 000

50,800

41,500

54,700

57, 000

44,600

56,800

64,300

43,000

49, 700

60,400

60,600

45, 300

50,800

63,200

38,100

36, 500

41,600

38,700

39, 000

38, 700

48,600

32,600

36,100

1, 552, 000

September

9,560

9,520

9,600

9,560

9,800

9,480

9,480

9,560

9,800

9,400

9,480

9,480

9,440

9,320

9,120

9,360

9,280

9,480

9,400

9,720

9,560

9,600

9,440

9,440

9,320

9,520

9,280

9,560

9,640

9,440

0.14

.14

.18

.24

:92

.91

.78

.40

.81

1.00

.92

.77

1.03

1.33

.79

.28

.32

.22

.20

.21

.22

.24

.20

.24

.23

.20

.22

.26

.26

.21

Total load for year.. . __ _ _ _ - ______ _ __ . ___ _ ________ .

36,100

36,000

46,700

61,900

243, 000

233,000

200,000

103,000

214,000

254, 000

236,000

197, 000

263,000

335, 000

195,000

70,800

80,200

56, 300

50,800

55,100

56,800

62,200

51,000

61,200

57, 900

51,400

55, 100

67,100

67, 700

53, 500

3,551^000

27,800,000
94 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 13. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Topock, Ariz., 

Oct. 1, 1934, to Mar. 81, 1989 Continued

1935

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..-

October

Mean 

discharge 

(secondfeet)

9,360

9,440

9,640

9,680

9,600

9,520

9,640

9,640

9,400

9,480

9,520

9,320

9,240

9,240

9,280

9,640

9,480

9,120

9,080

9,440

9,560

9,520

9,560

9,160

9.360

9,240

9,560

9,280

9,240

9,160

9,520

Suspended sediment

Mean 

percent

0.26

.21

.27

.24

.20

.28

.58

1.62

1.71

1.79

2.12

2.34

2.00

1.24

.51

.30

.25

.28

.26

.27

.31

.30

.34

.40

.26

.27

.28

.26

.27

.24

.33

Totalload (tons). _.

Tons per 

day

65, 700

53,500

70,300

62, 700

51,800

72, 000

151, 000

422, 000

434, 000

458, 000

545, 000

589, 000

499, 000

309,000

128, 000

78, 100

64, 000

69,000

63,700

68,800

80. 000

77, 100

87,700

98,900

65, 700

67,400

72,300

65, 100

67, 400

59, 300

84,800

5. 080, 000

November

Mean 

discharge 

(secondfeet)

9

AQ(\

, rtoU

9 280

9)440

9,480

9,680

9 120

9! 280

9 440

9' 120

9,640

9,320

9,520

9,400

9,520

9,440

9,240

9,280

9,280

9,480

9,520

9,360

9,360

9,540

9,470

9,640

9,320

9,520

9,560

9,440

9,360

Suspended sediment

Mean 

percent

0.24

.25

.28

.30

.31

.26

.24

.22

.27

.31

.26

.25

.29

.26

.30

.22

.20

.28

.28

.29

.32

.27

.23

.24

.23

.21

.29

.30

.26

.25

Tons per 

day

61,400

62, 600

71, 400

76.800

81,000

64, 000

60, 100

56, 100

66, 500

80,700

65,400

64, 300

73, 600

66,800

76,500

54,900

50, 100

70,100

71, 700

74,500

80,900

68,200

59, 200

61, 400

59,900

52, 800

74,500

77, 400

66, 300

63,200

2, 012, 000

December

Mean 

discharge 

(secondfeet)

8,050

5,040

4,900

4,870

4,830

4,700

4,730

4,700

4,730

4,700

4.700

4,800

4,560

4,660

4,530

4,700

4,530

4,730

4,630

4,630

4,700

4,630

4,560

4,660

4,630

4,730

4,700

4,590

4,630

4,900

4,660

Suspended sediment

Mean 

percent

0.22

.14

.13

.13

.14

.14

.13

.15

.20

.18

.18

.14

.16

.19

.24

.31

.23

.19

.16

.14

.12

.12

.12

.15

.16

.17

.19

.23

.17

.22

.15

Tons per 

day

47, 800

19, 100

17; 200

17, 100

18,300

17,800

16,600

19,000

25, 500

22, 800

22,800

18, 100

19,700

23,900

29, 300

39, 300

28, 100

24,300

20,000

17,500

15,200

15,000

14,800

18, 900

20,000

21,700

24,100

28,500

21,200

29. 100

18,900

691, 600

1936

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 

January

4,830

4,560

4,760

4,660

4,700

4,700

4,630

4,630

4,490

4,730

4,730

4,590

4,730

4,700

4,760

4,760

4,830

4,730

4,760

4,730

4,760

4,630

4,630

4,700

4,700

4,630

4,700

4,530

4,800

4,700

4,630

0.19

.19

.20

.16

.20

.20

.21

.16

.20

.20

.16

.18

.24

.23

.18

.15

.24

.20

.20

.18

.17

.18

.14

.13

.18

.19

.16

.19

.18

.19

.20

Total load (tons) ..

24,800

23, 400

25, 700

20,100

25,400

25, 400

26, 200

20,000

24, 200

25,500

20,400

22, 300

30, 600

29,200

23,100

19,300

,11, 300

25,500

25, 700

23, 000

21,800

22,500

17,500

16, 500

22,800

23, 800

20,300

23,200

23,300

24,100

25,000

731, 900

February

4,490

4,700

4,800

4,760

4,660

4,730

4,590

4,760

4,700

4,660

4,730

4,700

5,280

6,210

6,180

6,180

6,360

6,540

6,620

6,620

6,320

5,920

5,960

5,780

5,780

5,960

5,780

5,740

6,000

0.16

.11

.18

.18

.19

.16

.19

.19

.22

.20

.22

.25

.26

.16

.11

.16

.17

.21

.18

.18

.16

.19

.14

.16

.17

.20

.17

.19

.16

19,400

14, 000

23, 300

23, 100

23, 900

20,400

23,500

24, 400

27,900

25, 200

28,100

31,700

37,100

26,800

18, 400

26, 700

29,200

37,100

32,200

32, 200

27, 300

30,400

22,500

25,000

26,500

32,200

26,500

29,500

25,900

770, 400

March

6,000

6,320

6,070

6,280

6,500

6,920

7,260

8,660

8,660

8,820

9,340

9,460

9,460

9,620

9,540

9,780

9,540

9,420

9,960

9,620

9,620

9,580

9,640

9,480

9,400

9,720

9,600

9,600

9,400

9,640

9,670

0.17

.18

.14

.15

.14

.25

.16

.22

.16

.20

.19

.19

.16

.23

.18

.24

.18

.16

.22

.22

.14

.15

.25

.16

.16

.20

.24

. 18

.18

.17

.19

27,500

30, 700

23,000

25,400

24,600

46, 700

31,400

51, 400

37, 400

47,600

47, 900

48, 500

40,900

59, 700

46,400

63,400

46. 400

40,700

59, 200

57, 100

36,400

38,800

65,100

41,000

40, 600

52,500

62,200

46,700

 45, 700

44,300

49,600

1, 379, 000
QUANTITIES OF SUSPENDED SEDIMENT 95

TABLE 13. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Topock, Ariz., 

Oct. 1, 1934, to Mar. 31, 1939 Continued

1936

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

Mean 

discharge 

(secondfeet)

9,690

9,720

9,400

9 160

9.' 840

9,640

9,360

9,400

9,520

9,360

9,200

9,560

9,440

9,200

9,480

9,360

9,520

9,480

9,400

9,520

9,440

9,160

9,440

9,640

9,600

9,600

9,700

9,700

10, 200

10,600

Suspended sediment

Mean 

percent

0.19

.19

.17

.19

.22

.22

.18

.25

.15

.18

.16

.17

.16

.14

.19

.18

.16

.15

.17

.16

.14

.12

.22

.48

1.26

1.37

1.50

1.44

1.26

.79

Total load (tons)... ...

Tons per 

day

49.700

49, 900

43, 100

47,000

58,500

57, 300

45,500

63, 400

38,600

45, 500

39, 700

43, 900

40, 800

34, 800

48,600

45,500

41,100

38, 400

43, 100

41, 100

35, 700

29, 700

56,100

125,000

327, 000

355, 000

393, 000

377, 000

347, 000

226, 000

3, 187, 000

May

Mean 

discharge 

(secondfeet)

10,600

9,540

8,170

9 con f Q*U 

979fi

, ttAJ

10 000

9 QAfi j WJU

9,760

9,440

9,440

9,800

9,760

8,400

8,170

9,240

9,200

8,290

7,980

8,020

8,130

8,960

7,900

7,330

7,210

7,520

7,670

7,980

7,900

8,250

8,720

6,780

Suspended sediment

Mean 

percent

0.80

.88

.40

.22

.22

qo 

. o^

97 

. fit

1 99fiU

.20

.23

.19

.18

.15

.16

.14

.17

.14

.12

.18

.24

.30

.22

.20

.18

.20

.14

.22

.18

.13

.17

.14

Tons per 

day

229, 000

227, 000

88, 200

KC Cfifl UUT QUU

57, 700

86,400

72 600

58,' 000

51, 000

58,600

50,300

47, 400

34, 000

35, 300

34, 900

42,200

31, 300

25, 900

39, 000

52, 700

72,600

46, 900

39,600

35, 000

40,600

29,000

47, 400

38, 400

28, 900

40,000

25,600

1, 822, 000

June

Mean 

discharge 

(secondfeet)

8,050

8,960

8 920

9 000

9 240

9

onn , L\J\J 

99ftn , .6OU

8,840

8,880

8,880

8,840

8,560

8,560

7,860

8,720

8,960

9,320

9,280

9,880

10, 200

9,840

10, 200

10, 300

10, 400

10, 800

10,600

10, 800

10, 700

10, 700

11,000

Suspended sediment

Mean 

percent

0.22

.19

OK 

. ^U

.18

.20

.18

.12

.14i f;

. J-U

.18

.17

.13

.15

.15

1.15

.16

.16

1.16

.15

.15

.13

.16

.16

.17

.14

.13

.18

.15

.16

.14

Tens per 

day

47 800

46^000

60,200

AO 7firt

TCU, l\J\f

49 900

44 700

Of\ -\f\f\ O\Jt J.UU

33 400

ofi OUj HftA UUv

43, 100

40,600

30, 100

34, 700

31,800

35, 300

38,700

40,300

40, 100

40, 000

41, 300

34,500

44,100

44,500

47, 700

40,800

37, 200

52,500

43,300

46,200

41,600

1, 240, 000

1936

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....

r

July

11, 100 

11,000 

10,800 

11, 100 

10, 900

11,000 

11,000 

10,700 

10,600 

10,500

11,000 

11, 100 

10, 900 

10, 900 

10, 700

10,500 

10,600 

10, 700 

10,600 

10,600

10,500 

10,500 

10, 400 

10, 400 

10,400

10,500 

10, 800 

10,500 

10, 900 

10, 900 

10, 700

Potal load (

0.13 

.15 

.16 

.14 

.11

1.13 

1.13 

.15 

.14 

.14

.16 

1.15 

.14 

.10 

.14

>.15 

.15 

.16 

1.15 

.14

.13 

1.12 

.12 

1.10 

.08

.15 

.14 

.12 

1.13 

.14 

1.13

tons) __ _

39, 000 

44,600 

46, 700 

42,000 

32,400

38,600 

38,600 

43, 300 

40, 100 

39, 700

47,500 

45, 000 

41, 200 

29, 400 

40, 400

42,500 

42, 900 

46,200 

42,900 

40, 100

36,900 

34,000 

33, 700 

28, 100 

22,500

42,500 

40,300 

34,000 

38,300 

41,200 

37,600

1, 213, 000

August

10, 600

10,600

10, 100

9,760

10,100

9,520

8,960

9,240

9,120

9,040

9,040

9,000

9,240

9,240

0.12

.16

.10

.16

.14

.14

.14

.14

.13

.12

.12

.14

.13

.08

34, 300

45, 800

27,300

42,200

38, 200

36, 000

33,900

34,900

32,000

29, 300

29,300

34, 000

32,400

20,000

1, 030, 000

September

9,000

9,320

9,280

9,080 

9,400

8,960 

9,400 

9,120

9,600

9,200

9,160

8,560 

8,800

8,680 

8,170 

8,090

7,900

0.12

.11

.10

.08 

.12

.10 

.14 

.12

.15

.11'

.14

.14 

.15

.20 

.18 

.14

.14

29,200

27,700

25, 100

19,600 

30,500

24,200 

35, 500 

29,500

38, 900

27, 300

34,600

32, 300 

35,600

46,900 

39, 700 

30,600

29,900

953,400

i Estimated.
96 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 13. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Topock, Ariz., 

Oct. 1, 1934, to Mar. 31, 1939 Continued

1936

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 

October

Mean 

discharge 

(secondfeet)

7,780

7,590

7,670

7,780

7,940

7,980

7,670

7,290

7,060

7,290

7,360

6,910

6,760

7,250

6,950

7,440

6,950

6,990

7,550

7,170

6,880

6,840

6,910

6,180

6,470

7,140

6,470

6,320

7,100

6,840

6,280

Suspended sediment

Mean 

percent

10.16

.16

>.17

.19

1.20

.20

1.19

.17

.16 1.13

.13

J.14

.15

1.15

.10

.13

.13

.10

.12

.14

.18

.12

.15

.12

.14

.11

.14

.10

.12

.10

.11

Total load (tons) _ ..

Tons per 

day

31,500

32,800

35,200

39,900

42,900

43,100

39,300

33,500

30,500

25,600

25,800

26,100

27,400

29,400

18,800

26,100

24,400

18,900

24,500

27,100

33,400

22,200

28,000

20,000

24,500

21,200

24,600

17,100

23,000

18,500

18,700

853,900

November

Mean 

discharge 

(secondfeet)

6,210

6,100

6.070

5,960

6,070

6,140

6,100

6,030

5^640

5^ 920

5,890

5,920

5,820

6,180

6,250

5,850

6,800

6,030

6,030

5,740

5,710

5,740

5,820

5,740

5,710

5,420

5,110

4,900

5,110

5,180

Suspended sediment

Mean 

percent

0.13

.12

.16

- .12

.13

.14

.20

.14

.18

.20

.21

.20

.17

.20

.17

.17

.20

.16

.17

.16

.11

.14

.12

.18

.17

.15

.14

.12

.14

.12

Tons per 

day

21, 800

19,800

26,200

19,300

21,300

23,200

32,900

22,800

27,400

32,000

33,400

32,000

26,700

33,400

28,700

26,900

36,700

26,000

27,700

24,800

17,000

21,700

18,900

27,900

26,200

22,000

19,300

15,900

19,300

16,800

748,000

December

Mean 

discharge 

(secondfeet)

5,110

5,110

4,940

4,830

5,040

4,800

4,660

4,590

4,830

4,970

4,660

4,730

4,870

4,630

4,660

4,970

5,110

5,040

4,870

4,700

4,830

4,590

4,760

4,760

4,760

4,760

4,940

5,220

4,900

4,870

5,460

Suspended sediment

Mean 

percent

0.20

.25

.20

.18

.20

.17

.26

.17

.15

.19

.19

.25

.15

.18

.13

.15

.17

.17

.23

.16

.19

.13

.15 1.13

.11

.18

.13

.17

.11

.16

.22

Tons per 

day

27,600

34,500

26,700

23,oOO

27,200

22,000

32,700

21,100

19,600

. 25,500

23,900

31,900

19,700

22,500

16,400

20,100

23,500

23,100

30,200

20,300

24,800

16,100

19,300

16,700

14,100

23,100

17,300

24,000

14,600

21,000

32,400

715,400

1937

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 

January

5,820

5,080

3,880

4,760

4,260

4,870

5,250

4,970

4,730

4,660

4,490

3,630

4,900

4,940

4,800

4,560

4,560

4,300

4,170

4,830

4,730

6,000

4,660

4,700

4,300

3,970

4,800

4,700

4,660

4,730

4,800

0.22

.20

1.19

.23

.17

.22

.26

1.26

.25

.24

.22

.16

.25

.20

.18

.22

.18

.19

.16

.24

1.23

.28

.24

.25

.21

.18

.23

.20

.17

.16

.18

Total load (tons) __

34,600

27,400

19,900

29,600

19,600

28,900

36,900

34,900

31,900

30,200

26,700

15,700

33,100

26,700

23,300

27,100

22,200

22,100

18.000

31,300

29,400

37,800

30,200

31,700

24,400

19,300

29,800

25,400

21,400

20,400

23,300

833,200

February

4,590

4,010

4,830

4,940

4,830

4,870

4,970

4,900

4,940

4,870

4,830

5,080

5,080

5,180

5,320

5,110

5,220

5,530

5,530

5,500

5,320

5,110

5,140

5,110

5,220

5,600

5,960

6,470

0.24

.14

.28

.26

.28

1.23

.18

.24

.20

.22

.22

.24

.28

.30

.34

.20

.20

.23

.26

.23

.22

.20

.20

.19

.21

.22

.24

.26

29,700

15,200

36,500

34,700

36,500

30,200

24,200

31,800

26, 700

28,900

28,700

32,900

38,400

42,000

48,800

27,600

28,200

34,300

38,800

34,200

31,600

27,600

27,800

26,200

29,600

33,300

38,600

45,400

908,400

March

6,910

6,840

6,840

6,650

6,690

6,650

6,730

6,730

7,250

7,480

3,210

9,080

9,320

9,440

9,120

9,280

9,360

9,320

9,120

8,600

8,680

8,480

8,760

8,680

8,960

7,400

7,060

7,210

7,860

7,860

8,520

0.22

.14

.22

.22

.18

.21

.18

.16

.20

.13

.21

.25

.22

.22

.18

.15

.17

.24

.24

.13

1.20

1.20

.22

.23

.24

.23

.16

.28

.20

.26

.24

41,000

25,900

40,600

39,500

32,500

37,700

32,700

29,100

39,200

26,300

46,600

61,300

55,400

56,100

44,300

37,600

43,000

60,400

59,100

30,200

46,900

45,800

52,000

53,900

58,100

46,000

30,500

54,500

42,400

55,200

55,200

1, 379, 000

i Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 97

TABLE 13. Mean daily discharge, mean daily concentration, and daily load -of 

suspended sediment in the Colorado River at gaging station near Topock, Ariz.t 

Oct. 1, 1934, to Mar. 31, 1939 Continued

1937

Day

.1

2

3

4

5

6

7

8

9.....

10....

11--..

12....

13....

14....

15....

16....

17....

18....

19....

20....

21....

22....

23....

24....

26....

26....

27....

28....

29....

30....

31

*

April

Mean 

discharge 

(secondfeet)

8,760

9,000

9,240

8,940

8,640

8,680

8,920

8,600

8,720

8,520

8,760

8,760

8,480

8,960

8,760

9,200

9,040

8,760

8,760

9,120

8,920

9,080

8,960

8,960

9,000

9,320

9,000

9,280

8,880

8,960

Suspended sediment

Mean 

percent

0.20 '.IS

.16

1.18

.19

.19

.21

.16

.16

.18

.16

.16

.16

.18

.13

.16

1.18

.20

.18

.14

.14

.16

.19

.17

.24 .22'

.18

.15

.19

.24

Potal load (tons) __

Tons per 

day

47,300

43,700

39,900

43,400

44,300

44,500

KA fiofi OUj UUU

37,200

37,700

41,400

37,800

37, 800

36.600

43,500

30,700

39,700

43,900

47,300

42,600

34,500

33,700

39,200

46,000

41,100

58,300

55,400

43,700

37,600

45,600

58,100

1, 283, 000

May

Mean 

discharge 

(secondfeet)

9,320

9,600

9,640

9,680

9,280

8,880

9

AQ(\ i ^oU

9,600

9,200

9,040

9,200

9,320

9,240

9,080

8,560

8,290

8,330

8,330

8,050

7,820

7,780

7,860

7,900

7,670

7,590

7,590

7,780

7,630

7,860

8,050

8,330

Suspended sediment

Mean 

percent

1 0.18

.10

.12

.10

.10

.08

.14

.14

.12

.12

.14

.14

.15

.12

.15

».12

.10

.14

.14

.13

.10

.11

.11

.08

.10

.10

.11

.12

.11

.09

.10

Tons per 

day

45,300

25,900

31,200

26,100

25,100

19,200

35,800

36,300

29,800

29,300

34,800

35,200

37,400

29,400

34,700

26,900

22,500

31,500

30,400

27,400

21,000

23,300

23,500

16,600

20,500

20,500

23, 100

24,700

23,300

19,600

. 22,500

852,800

June

Mean 

discharge 

(secondfeet)

8,250

8,090

7,900

7,940

8,170

8,440

8,920

8,480

8,370

8,480

9,200

9,360

9,320

8,920

8,840

8,840

8,760

9,080

9,760

10, 700

10,200

9,880

10,000

9,880

10,500

10,600

10,700

10,700

10,800

10, 700

Suspended sediment

Mean 

percent

0.08

.10

.11

.10

.12

.12

.12

.10

.11

.10

.12

.12

.11

.09

.07

.10

.10

.11

.10

.10

1.10

.09

.08

.08

.16

.07

.10

.07

1.08

.09

Tons per 

day

17,800

21,800

23,500

21,400

26,500

27,300

28,900

22,900

24,900

22,900

29,800

30,300

27,700

21,700

16,700

23,900

23,7CO

27,000

26,400

28,900

27,500

24,000

21,600

21,300

45,400

20,000

28,900

20,200

23,300

26,000

752,200

1937

l-_ 

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

Jnly

10,700

10,300

10,700

10,300

10,500

10,500

10, 600

10,400

10,400

10,700

11,000

10,700

10,500

10,500

10,500

10,300

10,500

10,500

10,300

10,300

10,300

10, 100

10.4CO

10,400

10,300

10,300

10,400

10,600

10,500

10,600

10, ICO

0.12

.08

1.08

.08

.09

.11

.10

.10

.10

.09

i.C9

.08

.08

.09

1.10

.11

.OH

.12

1.10

.10

.08

.08

.08

.10

1.10

.11

.10

.11

.09

.12

.11

rotaltoad (tons) ......

34,700

22,200

23,100

22,200

25,500

31,200

28,400

28,100

28, 100

26,000

26,700

23,100

22,700

25,500

28,400

30,600

22,700

34,000

27,800

27,800

22,200

21,800

22,500

28,100

27,800

30,600

28,100

31,500

25,500

34,300

30,000

841,200

August

10,200

10,300

10,600

10,600

10,500

10,400

10,200

10,400

10,400

10,400

10,300

10,300

10,200

10,300

10,300

10,500

10,700

10,600

10,500

10,500

10,800

10,800

10,700

11,000

10,600

10,500

10, 300

10,200

9,920

9,880

9,600

0.11

.11

.11

1.11

.11

.08

.08

1.09

.10

.08

.10

.08

.08

.06

.08

.10

.10

.09

.10

.08

.16

.09

.07

.09

.16

.09

.10

.11

.08

.09

.14

30,300

30,600

31,500

31,500

31,200

22,500

22,000

25,300

28,100

22,500

27,800

22,200

22,000

16,700

22,200

28,400

28,900

25,800

28,400

22, 700

46,700

26,200

20,200

26,700

45,800

25; 500

27,800

30,300

21,400

24,000

36,300

851,500

September

9,560

9,880

10,100

10,500

9,680

9,640

9,520

9,840

9,680

9,600

9,400

9,240

9,280

9,200

8,960

8,920

8,520

8,620

8,370

8,250

8,330

8,330

8,370

8,400

7,980

7,980

7,860

7,820

8,090

7,980

0.08

.08

.08

.09

.10

.09

.06

.10

.11

.10

.08

.08

.08

.11

.12

.10

.06

.10

1.08

.07

.08

.12

.12

.12

.11

.10

.12

.09

.10

.10

20,600

21,300

21,800

25,500

26,100

23,400

15,400

26,600

28,700

25,900

20,300

20,000

20,000

 27,300

29,000

24,100

13,800

23,000

18,100

15,600

18,000

27,000

27,100

27,200

23,700

21,500

25,500

19,000

21,800

21,500

678,800

1 Estimated.
98 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 13. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Topock, Ariz., 

Oct. 1, 1984, to Mar. 31, 1939 Continued

1937

Day

1

2

3

4.....

5

6

7

8

9_--__

10_...

11----

12....

13....

14....

lS_-._

16....

17...-

18....

19-..-

20-...

21....

22....

23-...

24_...

25....

26-..-

27.-..

28....

29....

30....

31....

October

Mean 

discharge 

(secondfeet)

8,120

8,210

8,210

8,130

8,080

8,020

8,020

8,020

8,090

7,980

8,020

8,090

8,050

8,170

8,050

8,290

8,050

8,090

8,090

7,900

7,710

7,330

7,290

7,330

7,250

7,520

7,780

7,710

7,580

7,440

7,480

Suspended sediment

Mean 

percent

0.10

.10

.08

.14

.10

.10

.08

.10

.12

.10

.11

.12

.09

.08

.09

.10

.12

.10

.10

.11

.12

.09

.12

.12

.12

.08

.10

.08

.08

.12

.11

Total load (tons) ...

Tons per 

day

21, 900

99 £*&, 90A £Aj\j

17,700

30, 700

21, 800

21, 700

17, 300

91 7Hft Ji.lj (UU

26,200

21, 500

23, 800

26,200

19,600

17, 600

19, 600

22,400

26,100

21, 800

21,800

23,500

25,000

17,800

23, 600

23, 700

23,500

16,200

21,000

16,700

16,400

24,100

22, 200

675, 300

November

Mean 

discharge 

(secondfeet)

7,330

7,670

7,670

7,360

7 440

7,600

7 3ftfi /, oDU

6,990

6,320

6,840

7,140

6,910

6,210

6,580

6,540

6,210

6,840

7,020

6,990

6,540

6,360

6,210

6,320

6,650

6,730

6,500

6,430

6,180

6,390

6,070

Suspended sediment

Mean 

percent

0.08

.08

.10

.08

.10

.12

.11

.15

.10

.13

.10

.12

.09

.12

.08

.08

.12

.10

.10

.08

.09

.12

.10

.11

.08

.07

.09

.11

.13

.08

Tons per 

day

15,800

16, 600

20,700

15, 900

20,100

24,600

21,900

98 *5o, 3OA oUU

17, 100

24,000

19,300

22,400

15, 100

21, 300

14, 100

13,400

22, 200

19,000

18,900

14, 100

15,500

20,100

17, 100

19,800

14,500

12,300

15, 600

18,400

22, 400

13,100

553, 600

December

Mean 

discharge 

(secondfeet)

6,500

6,730

6

CQA

, UOU

6,390

6,100

5,960

5,670

6,070

6,470

6,800

7,060

6,950

6,800

5,710

6,250

6,500

6,390

6,320

6,180

6,070

6,070

6,070

6,250

6,250

6,500

6,140

6,650

6,030

6,000

6,140

6,280

Suspended sediment

Mean 

percent

0.10

.09

!l2

.16

.13

.10

.09

. 13J.O

.13

.14

.14

.17

.14

.14

.16

1. 16

.15

.15

.19

.20

.17

.21

.18

.15

1.22

.21

.19

.14

.14

.15

.14

Tons per 

day

17,600

16, 400

21,300

27,600

21,400

16,100

13,800

21,300

22,700

25,700

26,700

31,900

25,700

21,600

27,000

28,100

25,900

25,600

31,700

32,800

27,900

34,400

30,400

25,300

38,600

34,800

34,100

22,800

22,700

24,900

23,700

800,500

1938

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....

29....

28....

30--..

31....

January

6,030

5,640

5,960

5,390

5,920

6,030

5,820

6,030

6,210

6,000

5,220

5,740

6,030

6,320

6,280

6,320

6,070

5,670

6,470

6,990

6,850

6,390

6,000

5,820

5,460

6,100

6,320

6,100

6,000

6,250

6,250

0.15

.12

.14

.13

 14

.14

.15

.22

.16

.14

.14

.13

.10

.13

.09

.13

.11

.11

.14

..12

.12

.14

.16

.17

.12

.22

..15

.17

.14

.20

.18

Total load (tons) ...

24,400

18,300

22,500

18,900

22,400

22,800

23,600

35,800

26,800

22,700

19,700

20,100

16,300

22,200

15,300

22,200

18,000

16,800

24,500

22,600

22,200

24, 200

25,900

26,700

17,700

36,200

25,600

28,000

22, 700

33,800

30,400

729, 300

February

5,740

6,430

6,500

6,690

6,620

6,280

6,360

5,670

6,650

6,910

6,650

6,390

6,390

6,320

5,710

6,760

6,620

6,140

6,140

6,540

6,180

5,280

5,960

6,000

6,070

5,780

5,740

6,180

0.10

.16

.22

.13

.17

.20

.20

.14

.20

.20

.12

.18

.16

.11

.10

.15

.16

.19

.16

.16

.17

.12

.18

.14

.13

.13

.13

.14

15,500

27,800

38,600

23,500

30,400

33, 900

34,300

21,400

35,900

37,300

21, 500

31,100

27,600

18,800

15,400

27, 400

28, 600

31, 500

26, 500

28,300

28,400

17,100

29,000

22, 700

21,300

20,300

20,100

23,400

737,600

March

6,620

6,470

6,950

7,480

6,360

5,140

5,360

5,420

5,670

5,850

5,850

5,560

6,250

7,400

6,990

7,400

7,210

7,360

7,440

7,590

8,210

8,290

8,330

8,600

8,640

8,840

9,080

9,480

9,160

9,160

9,160

0.10

1.10

1.15

1.25

.24

.11

.13

.11

.14

.13

.15

.08

.08

.12

.10

.12

.10

.15

.15

.09

.17

.15

.16

.16

.16

.14

.16

.14

.13

.20

.15

17,900

17,500

28,100

50,500

41,200

15,300

18,800

' 16,100

21,400

20,500

23,700

12,000

13,500

24,000

18,900

24,000

19,500

29,800

30,100

18,400

37,700

33,600

36,000

37,200

37,300

33,400

39,200

35,800

32,200

49,500

37,100

870,200

i Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 99

TABLE 13. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Topock, Ariz., 

Oct. 1, 1934, to Mar. 31, 1939 Continued

1938

Day

1 

2.....

3- -

4.....

5.....

6.....

7.....

8-....

9.....

10 

11 

12....

13 

14 

15 

16 

17 

18 

19 

20 

21. 

22-...

23. 

24 

25 .

26 .

27_...

28 

29-..

30 

31

April

Mean 

discharge 

(secondfeet)

9,160

9 040

9^160

9,000

9 040

9,120

9,200

9,200

9,160

9,240

9,280

9,320

9,280

9,240

9,480

9,320

9,400

9,660

11,000

11,400

11,600

10,300

9,400

9,400

8,440

9,600

9,480

9,360

9,360

9,360

Total load (

Suspended sediment

Mean 

pereent

0.17

. 12

. 13

!l4

.24

.15

.15

.16

.11

.10

.10

.10

.14

.10

.14

.10

.14

.10

.32

.16

_ .13

.10

.09

.08

.09

.09

.08

.12

.08

.10

tons) __ .

Tons per 

day

42 000

29' 300

32,200

34,000

58,600

36,900

37,300

39,700

27,200

24,900

25,100

25,200

35, 100

24,900

35, 800

25,200

35,700

25, 800

35, 600

49,200

40,700

27,800

22,800

20,300

20,500

23,300

20,500

30, 300

20,200

25,300

931, 400

May

Mean 

discharge 

(secondfeet)

9 360

9,' 360

9,440

9,480

9,360

9 400

9*360

9 400

9 360

9,' 360

9,320

9,040

8,480

8,480

8,520

8,520

8,370

8,400

8,370

8,290

8,210

8,370

8,370

8,250

8,210

8,480

8,330

8,210

8,400

8,640

8,370

Suspended sediment

Mean 

percent

0.10

.12

.14

.15

1.16

.16

.15

.13

.11

.14

.10

.11

.11

.08

.09

.06

.10

.12

.11

.10

.10

.09

.11

.12

.08

.09

.10

.09

1.08

.07

.09

Tons per 

day

25 300

.30^300

35, 700

38,400

40 400

40 600

37! 900

33, 000

27,800

35, 400

25,200

26,800

25,200

18,300

20,700

13, 800

22,600

27,200

24,900

22,400

22,200

20,300

24,900

26,700

17,700

20,600

22,500

20,000

18, 100

16,300

20,300

801,500

June

Mean 

discharge 

(secondfeet)

8

AA{\ 

, rtlU

O AAC\ O» T:rrU

8,520

9,080

9 19fl t ia(j

9,080

9,040

9

1 Oft 

, IjiU

8,840

8,880

9,120

9,000

9,000

9,240

9,160

9,200

9,040

9,160

9,120

9,120

9,200

9,200

9,240

9,360

12,700

14, 100

14, 100

14,600

15,400

10,100

Suspended sediment

Mean 

percent

0.10

.10

.14

.12 1.12

.12

.15

.12

.15

U9

.19

.14

.11

.11

.10

.09

.12

.15

.16

.15

1.12

1.10

.08

.07

.24

.14

.14

.17

.18

.11

Tons per 

day

22,800

22,800

32,200

29,400

an Efin ftO) UUU

29,400

36,600

90 *y >Wl r ouu

35,800

45,600

46,800

34,000

26,700

27,400

24,700

22,400

29,300

37,100

39,400

36,900

29,800

24,800

20,000

17,700

82,300

53,300

53,300

67,000

74,800

30,000

1, 091, 000

1938

1_ 

2 

3 

4 

5 

6 -

7 

8 _.

9 

10 

11 .

12 

13 

14 

16 

16 

17 

18 

19.--.

20 

21 .

22 

23 .

24 

26 

26 

27 

28 

29 

30....

31 

July

9,480

11,100

16,900

10,700

10,600

10,500

10,400

10,300

10,400

10,400

10,500

10,500

10, 400

10,600

10,400

10,500

10,500

10, 400

10,400

11,000

11,200

10,800

10,500

10,500

10, 700

10,600

10,500

10,500

10,600

10, 600

10,700

0.12

.IB

.07

.10

.08

.12

.10

.10

1.10

1.09

1.08

.07

.08

.06

.10

.10

.09

.08

.08

.08

.08

.08

.10

.10

.12

.12

.12

.09

.11

.10 1.10

Total load (tons)... ...

30,700

48,000

31,900

28,900

22,700

34,000

28,100

27,800

28,100

25, 300

22, 700

19, 800

22,500

17,200

28,100

28,400

25,500

22,500

22, 500

23,800

24,200

23,300

28,400

28,400

34,700

34, 300

34,000

25,500

31,500

28,600

28,900

860.300

August

10,600

10,500

10,500

10,700

10,800

10, 700

10,700

10,700

10,600

10,500

10,700

10,600

10, 700

10,900

10, 800

10,200

10,200

9,760

9,800

9,720

9,920

9,760

9,640

9,760

9,640

9,800

9,600

9,200

9,120

9,120

9,480

0.08

.10

.09

1.10

.10

.12

.11

.11

.10

.12

.10

.08

.09

.14

.16

.18

.14

.09

1.10

.12

.11

.11

1.11

.11

.10

.10

.09

.07

.11

.11

.10

22,900

28,400

25,500

28,900

29,200

34,700

31, 800

31, 800

28,600

34,000

28,900

22,900

26, 000

41,200

46, 700

49,600

38,600

23,700

26,500

31,500

29,500

29,000

28,600

29,000

26, 000

26,500

23,300

17,400

27, 100

27,100

25,600

920,500

September

9,480

9,200

9,200

9,200

9,040

9,080

9,240

9,280

8,960

9,200

9,280

9,360

9,320

9,320

9,320

9,080

9,280

9,440

9,280

9,200

9,240

9,240

9,200

9,040

8,800

8,720

8,600

8,680

8,560

8,640

0.12

.10

.07

.10

.10

.09

.07

.09

«.07

1.07

.09

.12

.09

.13

.09

.10

.10

.10

.09

.14

.12

.12

.12

.12

.08

.11

.10

.11

.10

.07

 

30,700

24,800

17,400

24,800

24,400

22,100

17,500

22,600

16,900

17,400

22,600

30,300

22,600

32,700

22,600

24,500

25,100

25,500

22,600

34,800

29,900

29,900

29,800

29,300

19,000

25,900

23,200

25,800

23,100

16,300

734,100

1 Estimated
100 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 13. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Colorado River at gaging station near Topock, Ariz., 

Oct. 1, 19S4, to Mar. SI, 1939 Continued

1938

Day

1...-

2-..-

3.....

4.. 

6 

6 

7.. 

9.. 

10....

11....

12....

13.-.. 

14....

15....

16.... 

17.... 

18-.. - 

19.-.. 

20....

21.... 

22.... 

23.... 

24.... 

25....

26.... 

271... 

28.... 

29.... 

30.... 

31....

r

October

Mean 

discharge 

(secondfeet)

8,600 

8,600 

8,440 

8,600 

8,400

8,090

12. 900 

13,000 

12,800

13, 100 

13,000 

13, 100 

13, 100 

12,800

12,900 

13,000 

13,000 

12,900 

13, 300

14,600 

14,800 

14,800 

15, 000 

14, 800 

14,800

Total load (

Suspended sediment

Mean 

percent

0.11 

.12 

.10 

.10 

.12

.16

.15 

.09 

.12

.18 

.25 

.18 

.18 

.18

.17 

.16 

.18 

.14 

.16

.16 

.13

.16 

.11 

.10 

.16

tons) i .....

Tons per 

day

25, 500 

27, 900 

22,800 

23,200 

27,200

34, 900

52, 200 

31, 200 

41,500

63, 700 

87, 800 

63,700 

63, 700 

62, 200

59,200 

56,200 

63,200 

48,800 

58,300

63,100 

51, 900 

63,900 

44,600 

40,000 

63,900

1,480,000

November

.Mean 

discharge 

(secondfeet)

15, 200 

15, 000 

16, 200 

17,500

17. 900 

17,600

17,400

17, 300 

17, 300 

17,400 

17,400 

17, 300

15, 600 

9,790 

7.620 

7,560 

7,500

7,700 

7,680

7,620 

7,430

7,500 

7,560 

7,560 

7,500 

7,430

Suspended sediment

Mean 

percent

0.18 

.17 

.19 

.18

.24 

.19

.14

.15 

.10 

.09 

.13 

.14

.08 

.05 

.04 

.04 

.04

.04 

.02

.02 

.02

.01 

.01 

.01 

.01 

.01

... _ ............. _

Tons per 

day

73,900 

68,800 

83, 100 

85, 000

116, 000 

90,300

65, 800

70, 100 

46,700 

43, 700 

61, 100 

65,400

35, 800 

12,400 

9,260 

7,550 

7,700

7,690 

3,730

3,290 

3,210

2,230 

2,040 

2,040 

1,820 

1,600

1, 240, 000

December

Mean 

discharge 

(secondfeet)

7,430 

'7,500 

7,500 

7,430 

7,680

7,500

6,060 

6,000 

6,060

5,430

9,400 

10, 700

6,950 

6,590 

6,350 

5,660 

5,600

6,000

6,150

5,600 

4,930 

4,650 

5.770 

6,060 

6,000

Suspended sedifflteHt

Mean 

percent

0.01 

.01 

.01 

.01 

.01

.01

.00 

.00 

.01

.01

.19 

.13

.01 

.00 

.00 

.00 

.01

.00

.00

.00 

.00 

.01 

.01 

.02 

.01

Tons per 

day

2,010 

2,230 

1,420 

1,000 

1,870

1,220

1,640

1,170

48,200 

37,600

1,310

1,360

879 

1,250 

2,450 

2.110

120,000

1939

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....

r

January

5,770 

4,980 

4,930 

5,890

6,000 

6,300 

5,890 

5,610 

4,870

5,660 

5,830 

6,060 

6,180 

6,590

4,860 

5,040 

5,720

12,600

13,600 

13,700 

14, 700 

16, 000

17,800 

18,200 

20,000 

23,900 

26,000 

29,500

Total load (

0.01 

.00 

.01 

.01

.01 

.01 

.01 

.01 

.01

.01 

.01 

.01 

.01 

.01

.01 

.01 

.01

.10

.11

.08 

.14 

.11

.10 

.33 

.24 

.16 

.12 

.20

tons)'.....

1,090

1,600 

1,910

1,780 

2,040 

1,750 

1,670 

1,050

1,380 

1,260 

1,960 

2,000 

2,140

 1, 180 

1,360 

2,010

32, 300

40,400 

28.500 

55,600 

47,500

47, 100 

162, 000 

130,000 

103, 000 

84,200 

159, 000

991. 000

February

24, 600 

19, 700 

19,200

19,500 

21,600 

25, 400 

24, 000 

24,200

24,800 

24, 300 

24, 800 

26,600 

26,600

6,250 

13, 600 

25, 100 

25, 500

23, 700 

23,900 

. 24,500 

24,800 

23,600

24,000

0.07 

.04 

.10

.06 

.13 

.11 

.09 

.08

.15 

.16 

.08 

.31 

.10

.02 

.24 

.14 

.14

.16 

.16 

.10 

.14 

.12

.14

_____ . _______ .

46,500 

23,400 

49,800

32,600 

75, 800 

75,400 

58, 300 

52,900

100, 000 

105, 000 

53,600 

223,000 

71,800

3,210 

88,100 

94, 900 

96,400

102,000 

103, 000 

66,200 

93, 700 

76,500

90,700

2,200,000

March

20,200 

19,600 

13,900

5.530 

4,760 

8,170 

9,080 

11, 100

10, 100 

7,940 

8,370

10, 300

9,440 

7,780 

10,600 

9,200 

9,680

9,960 

9,480 

9,440 

9,720 

10,800

12,900

9,720 

8,600 

10,000

0.18 

.08 

.06

.02 

.01 

.03 

.03 

.04

.03 

.03 

.02

.03

.03 

.02 

.02 

.02 

.03

.03 

.04 

.03 

.04 

.04

.02

.04 

.05 

.04

98,200 

43,400 

23,300

2,390 

890 

6,840 

8,340 

11, 700

7,360 

6,430 

5,200

8,900

7,140 

4,410 

4,580 

6,960 

8,620

8,070 

9,980 

8,410 

9,970 

12,000

7,660

11,000 

10,900 

11,900

469,000

1 Includes estimates for missing days.
QUANTITIES OF SUSPENDED SEDIMENT 101

TABLE 14. Mean daily concentration of suspended sediment in the Green River 

at gaging station near Green River, Irtah, May 1, 1929, to Sept. SO, 1939

1929-30

Day

1

?,

3....

4

5....

6-.-

7....

8

9 . in

11

12

13

14

15

16

17

18

19

20

21

W.

23...

24 

25...

fR

27

28

29

30

31

October

NovemberDecember

JanuaryFebruary March April May

n a

.42

.42

.38

.36

in

.47

.36

.31

.31

.27

.30

.27

.25

.24

.24

.23

.26

.19

.21

.18

.28

.23

.24

.24

.28

.25

.22

.36

.50

.58

June

0.57

.54

.55

.59

.56

.48

.44

.41

.40

.45

.36

.36

40

.42

.41

.43

.48

.44

.72

.66

.39

.31

.30

.27

.26

. .24

.18

.18

.16

.14

July

0.16

.12

.11

.09

.08

.07

.07

.10

.08

.07

.15

3.65

.18

.17

.27

.82

.32

.31

.60

.49

.28

.59

.70

.30

.35

.20

.13

.26

.17

.11

August

0.12

.31

3.90

3.78

2.19

2.08

1.86

1.34

3.25

4.22

3.43

3.53

2.55

3.49

2.99

3.10

3.10

2.40

2.04

1.56

1.17

.88

.58

.44

1.16

.41

.38

.33

.22

.29

September

0.33

.48

.64

.53

.62

1.26

1.20

.50

1.05

.54

.32

.21

.14

.11

.09

.09

.08

.09

.10

.11

.08

.65

.38

.36

.79

.74

1.52

1930-31

1

?:

3

4

5

6

7....

8....

9-...

10

11...

12 

13

14

15

16

17

18

19 

20 

21 

n

n

24

25...

26

?,7

38

VW

30

31

0.97

.62

.59

.76

.60

.51

.47

.24

.26

.25

.28

.26

.28

.22

.18

.17

.17

.16

.16

.15

.12

.12

.10

.09

.09

.10

.08

.08

.19

.09

.06

O fU

.04

.05

.05

.04

.04

.05

.05

.06

.06

0.05

.05

.06

.06

.08

.08

no

.07

08

.07

.06

.07

.09

.14

, .16

.17

O1

.26

.26

.25

90

.36

.39

.34

34

.42

43

.35

.30

.26

.20

0.12

1 9

no .11

.12

.13

.18

.22

' 3019

.30

OK

.27

.32

.36

.40

.42

.38

.40

.41

.34

in

.40

.49

.41

.35

.33

.2ff

.21

.18

0.16

11

.18

.14

.20

99

99

.26

QQ

on

90

OA

Oft

.24

.21

.20

.17

.26

.66

.76

.68

.63

.49

.41

.27

.18

.17

.24

.32

.30

.28

0.25

Of

.23

.20

.18

.24

.27

.26

.24

97

on

.35

.26

.20

.21

.20

.17

.18

.18

.16

.14

1O

.12

.12

.06

.06

.08

.08

.03

.03

0.02

1O

.02

.04

.06

.08

. .07

.07

03

.08

.06

.05

ru

.03

.03

.02

.02

.02

.02

.02

.02

.02

.01

02

.03

.03

.03

.03

.03

.03

.20

2.49

.73

.26

.10

.11

.50

1.30

1.56

.55

.36

. 2.13

1.67

1.33

.80

.46

.18

.10

.19

.10

.10

.16

.12

.13

.12

.09

.11

.11

.09

.10

.16

.22

0.30

.94

.30

.16

.07

.04

.11

.07

.11

.11

.08

.08

.08

.05

.04

.04

.13

.06

.04

.03

.04

.05

.05

.07

.20

.10

.09

.14

.10

1.52
102 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 14. Mean daily concentration of suspended sediment in the Green River at 

gaging station near Green River, Utah, May 1, 1929, to Sept. SO, 1939 Continued

1931-32

Day

1

2

3

4 

,5

fi

7

8....

9 

10 

11

12

13

14

15

16

17 

18

1920

212?

23-.

24

25...

26

27

28

29

30

31

October

1.08

.26

.37

.26

.13

.13

.03

.01

.04

.12

.14

.07

.01

.02

.08

.17

November

0.22

.41

.40

.22

.08

.31

.16

.04

.04

.06

.08

.05

.04

.01

.02

.04

December

0.06

.05

.01

January

0.06

.06

.04

.04

.05

.05

.04

February

0.06

.04

.05

.06

.07

.13

.09

.07

ftfi

.05

.04

.04

.09

.07

.06

19

.14

.ii

March

0.07ftfi

.06

.19

.23

.17

.15

.11

.08

.07

.09

.72

1.30

.86

.65

.60

.54

.47

April

0.46

.42

1.38

1.80

1.35

.99

.62

.55

.31

.52

.56

.78

.63

.62

.46

.36

.32

May

0.38

.82

.80

1.03

.76

.66

.66

.68

.84

.81

.73

.62

.62

.64

.54

June

0.49

.48

.35

.36

.40

.41

.35

.37

.38

.38

.40

.42

.40

.43

..40

.42

.37

.42

July

0.50

.35

.31

.21

.40

1.16

.78

.48

.16

.32

.39

.22

.13

.15

.14

.42

August

0.17

.54

.36

1.26

.93

.17

.08

.07

.08

.68

.50

.46

1.33

.51

1.60

3.41

2.90

September

2.52

1.08

.32

.58

.49

.23

.71

.12

.08

.05

.04

.05

.05

.08

.04

.06

1932-33

1

2....

3

4

5_...

fi

7

R

g

10

11 

12...

10

14

15___

Ifi

17...

18

1Q

on

01

99

23...

714

?,5

26

97

?,8

?,9

30

31

0.01

.02

04

.02

.01

.01

.02

.05

.18

.02

.02

06

.16

.06

f\A

.05

.06

6.03

.04

04

04

(Vt

04

04

.05

05

.02

ftO

.03

(Vt

.04

.02

0.01

.01

.02

.02

.04

.03

(Vt

ft9

0.05

.05

0.05

.01

.02

.02

.02

09

.02

.03

04

.03

04

.02

03

- .05

03

03

03

04

.03

.03

0.06

.05

.04

.04

.14

.14

.22

.12

.18

91

.29

KQ

.26

0.36

.34

.23

.12

.10

.11

.13

.58

.52

.41

.56

0.84

.52

.43

.37

.30

.28

.20

.16

.16

.30

.66

.60

.35

0.49

.64

.48

.45

.42

.38

.34

.32

.32

.34

.32

.18

.12

0.10

.09

.07

2.26

.32

.51

.78

.74

1.07

.36

.23

.14

.16

.05

.11

.37

0.30

.61

.35

.65

.08

.08

.29

.06

.03

.08

.07

.07

.02

.02

.04

0.02

.02

.02

1.48

2.91

.25

.06

.03

.08

.02

.05

.03

.04

.02

.01
QUANTITIES OF SUSPENDED SEDIMENT 103

TABLE 14. Mean daily concentration of suspended sediment in the Green River at 

gaging station near Green River, litah, May 1, 1929, to Sept. SO, 1939 Continued

1933-34

Day

1

2 

5

6. 

7....

10 

11 

10

10

14...

15...

16

17

18

1Q

oft

21...

22__.

23

?4

25

f,f>

2728

?,9

30

31

October

3.42

.25

.08

.06

fu

04

04

.03

no

.03

.03

.02

.03

.02

.02

.01

.02

.03

November

0 04

fw

.03

.12

19

.05

04

04

.03

.04

.04

.05

.04

.02

.02

.02

December

--.

0.05

04

.03

04

.02

n<t

.05

.06

.06

.02

January

0.09

.10

.09

.09

04

04

04

.05

- .04

.03

.03

.03

.04

.03

.03

February

0.03*

fU

.05

.06

.08

.14

.12

.12

.09

.04

.04

.04

.03

March

0.02

03

.02

04

nfi

(U

.04

April

0.07

.07

.24

May

0.18

.14

.11

.11

.09

.11

.16

.25

.22

.25

.19

.12

.10

.10

.10

.12

.08

.08

June

0.07

.06

.07

.04

.03

.02

.02

.02

.02

.01

.01

.01

.01

.01

.01

.01

.01

July

0.02

.01

.01

.01

.02

.02

.01

.02

August

0.02

.04

.05

.04

.04

.08

.04

.04

.05

September

0.09

.05

.03

.03

.11

.05

.oa

.07

.04

.04

.03

.03

.02

1934-35

1

2

3

4

ft

6

7

8

9

10

11 

12...

13...

14...

15 

16...

17...

18...

19

20

31

22

?,3

?,4

25

W

27

28

29

30

31

0.03

.03

.03

.02

.02

.03

.03

.03

.03

.02

.03

0.03

.02

.03

.02

.03

.03

.04

.04

.03

.02

.03

.03

.03

.03

.03

0.02

.04

.04

.04

.02

.01

.02

.02

.04

.04

.03

.03

.03

6.05

.04

.02

.02

.02

.02

.03

.03

.04

.10

.06

.04

.04

.04

04

0.04

.04

.04

.04

.04

.04

.06

.06

.05

.04

.04

.05

6.07

.11

.09

no

nfi

.07

.15

.24

.49

.19

99

.13

0.10

.10

.10

.11

.12

.35

.19

.11

.10

.09

.08

OO

.34

0.26

.26

.20

.20

.15

.58

.55

.38

34

.30

.57

.91

.83

0.69

.70

.46

<*Q

.34

.37

.46

.48

.46

.37

.36

.33

.19

.16

0.15

.08

.07

.06

.05

.04

.06

.,06

07

.31

.18

.07

.04

ns

0.10

.06

04

.23

.11

. .11

.08

.04

. .06

2.92

2.41

.84

1.17

.75

1.13

48

.26

1.00

.99

.46

0.53

.11

.06

.15

.13;

1.80

.44

.34

.08

.06

.02

.05

.05

.04

.02
104 SEDIMENT IN COLQKAIK) EIVER, 1925-41

TABLE 14. Mean datly concentration of suspended sediment in the Green River at 

gaging station near Green River, Utah, May 1, 1929, to Sept. SO, 19S9 Continued

1935-36

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 

Won

01

October

0.02

.54

.04

.02

.02

.02

.01

.03

.02

.02

.02

.02

November

0.02

.03

.04

.03

.03

.03

.04

.03

.02

.03

.02

.02

.02

.02

December

0.04

.05

.04

.03

.01

.02

.Ii

.01

January

0.01

.01

.02

.04

.04

.04

.02

.04

.04

February

0.02

no

.04

.04

.03

.05

.06

.05

.06

.06

.06

March

0.06

.07

.06

.08

.16

.14

.20

.15

.14

.11

.06

.05

.05

.06

April

0.05

.04

04

.05

.04

04

.06

.60

.47

1.07

1.12

1.12

.90

.72

.56

.55

May

0.43

OQ

.42

4O

.37

.32

.34

.38

.38

.41

.32

.30

.28

.26

.25

June

0.24

.34

.22

.20

.20

.16

.18

.18

.18

.15

.13

.10

.10

July

0.10

.08

.14

 .05

.2i

6.36

3.15

1.26

.51

1.06

.57

.85

.73

.38

.46

.56

.56

.36

.42

.92

August

1.15

1.36

3.31

2.95

2.22

1.56

1.40

1.20

.86

.64

.40

.35

2.51

.59

.75

.96

.88

.49

.46

1.18

3.82

September

1.37

QQ

3 Oft

1.66

2.72

.64

OQ

.20

.78

.60

1.39

1.56

.87

.18

.12

.10

.09

.07

.08

.06

.06

1936-37

2 .

4

5 

6. 

7 -

10 

11 

13 

14 

it

16...

17 

18...

10

20 

21 

22 

00

24...

25 

26...

27...

28.. .

29... <?n

31...

0.07

.06

.07

.06

.07

.06

.26

.68

.28

.73

.24

0.74

.69

.28

.16

."15

.12

.12

.11

.27

.21

0.10

.05

.06

.02

.03

.08

.07

.06

0.02

' .03

.02

.06

04

.05

03

0.03

.03

.06

.06

.06

.12

.10

0.22

.28

.28

1.07

9 9fl

.61

.35

0.30

.41

.60

.50

1.58

.98

.56

0.41

.77

.95

.44

.36

.30

.66

0.40

.41

.36

.37

.21

.16

.18

.16

.13

.15

.20

.28

.15

.15

0.23

.47

.14

1.20

.35

.72

.71

1.04

2.25

2.90

3.29

2.82

2.36

1.90

1.04

.86

.39

.47

.24

.19

.16

.32

1.04

0.56

1.66

.36

.22

.38

.61

.16

.09

.18

.41

.12

.10

.35

2.84

3.04

2.65

1.2&

.81

.08

.06

.05

.07

.12

.60
QUANTITIES OF SUSPENDED SEDIMENT 105

TABLE 14. Mean daily concentration of suspended sediment in the Green River at 

gaging station near Green River, Utah, May 1, 1929, to Sept. SO, 1939 Continued

1937-38

Day

1

?:

3

4

5

6

7

8

fl

10

11

12

13

14

15

Ifi

17

18

19?o

?1

9:?: ?3

?A

35

?fi w

?8

?9

30

31

October

0.12

.09

.06

.05

.05

.08

.18

.20

.68

.63

.12

November

0.12

.08

.07

.06

.05

.05

.06

.04

.04

.05

.04

.07

December

0.06

.08

.07

.08

.07

.04

.07

.14

.42

.25

.22

.10

.06

.05

.03

January

0.02

.02

.04

.04

.02

.04

.04

.04

.03

.04

.02

February

0.04

.04

.06

.05

.05

.07

.13

.07

.06

.07

.08

.08

March

0.08

1.84

1.04

2.70

1.44

.98

.72

.40

.25

.35

.52

.55

.48

.38

.43

.27

April

0.28

.18

.16

.13

.12

.12

.19

.16

.20

.35

1.10

1.75

1.24

.98

.87

.90

May

0.78

.72

.37

.33

.22

.36

.83

.73

.68

.57

.44

.52

June

0.37

.38

.34

.32

.37

.29

.26

.24

.24

.24

.25

.22

.89

July

0.33

.24

.24

.16

.11

.14

.30

.27

.22

.36

.09

.08

August

0.07

.08

.04

.04

-3.35

.49

.15

.41

.30

.25

.12

.05

.13

September

0.77

1 fid

5. 68

4.08

1.85

2.08

2.42

.20

.17

.14

.10

1938-39

?

3

4

fi

6

7

8

fl

10

11

1?

13

14

15

1fi

17

18

W

31

?!?

23

94

?5

?«

?7

28

29

30

31

0.09

.07

.30

1.06

1.15

.92

.82

.96

1.04

.37

.26

.22

.18

.14

0.12

.11

.26

.19

.09

.09

.08

.08

.06

.06

.06

.06

.05

.05

0.04

.04

.07

.09

.09

.07

.05

.02

.03

.03

.03

.03

.02

.02

.02

0.01

.03

.03

'

.04

.05

.05

.02

.04

.03

.05

.04

.02

.02

.03

0.06

.07

.11

.03

.04

.03

0.04

fir,

.04

.06

.06

.05

.04

.07

.16

.20

1.72

2.02

1.55

1.58

1.51

1.40

1.28

1.26

1.33

.98

0.61

.52

.38

.39

.36

.36

.32

.26

.23

.20

.18

.22

.24

.23

.26

.24

.45

.27

0.71

.45

.75

.68

.58

.55

.58

.47

.44

.41

.37

.33

.32

.38

.31

.37

.30

.31

.29

.22

.23

0.22

.36

.46

.58

.38

.42

.25

.26

.14

.18

.17

.14

.10

.11

.09

.08

.07

.06

.05

0.04

.03

.01

.01

.02

.02

.02

.02

.02

.04

.03

.02

.02

.01

.01

.55

0.09

.06

.17

.12

.13

.26

.16

.11

.09

.05

.04

.04

.03

.02

.02

.02

.03

.31

0.10

.08

.06

.04

3.37

1.01

.22

.70

1.18

2.44

.84

1.22

.55

.26

.16

.10

:08

.15

.20

.11

.07

.06

.06

.10

.12
106 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 15. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Green River at gaging station near Green River, Utah, 

Oct. 1, 1939, to Sept. 30, 1941

1939

Day

1__.__

2.- 

3

4

5

6

7

8

0

10.--.

11....

12.--

13..-

14..-

15.--

16-...

17-.-

18-.-

19....

20..-

21--

22-...

23..-

24....

25---

26..-

27....

28..-

29.--

30....

bl--_

October

Mean discharge 

(secondfeet)

1,850

1,850

1,850

1,960

1,800

i.'-sgo

2,240

2,340

2,780

2,340

2,670

2,670

2,340

2,180

2,140

2,110

2,090

2,090

2,030

1,980

1,920

1,910

1,870

1,840

1,820

1,800

1,780

1,750

1,910

1,940

1,870

Suspended sediment

Mean 

percent

0.08

.07

.14

.21

.26

.20

.12

.15

1.02

.47

.28

.56

.64

.55

.28

.16

.23

.14

.09

.07

.06

.06

.05

.05

.06

.04

.04

.03

.04

.04

.04

Monthly load (tons)__

Tons per 

day

4,000

3,500

6,990

11,100

12, 600

10, 200

7,260

9,480

76,600

29,700

20,200

40,400

40, 400

32,400

16, 200

9,120

13, 000

7,900

4,930

3,740

3,110

3,090

2.520

2,480

2,950

1,940

1,920

1,420

2,060

2,100

2,020

385, 200

November

Mean discharge 

(secondfeet)

1,840

1,820

1,780

1,770

1,770

1,770

1,750

1,730

1,750

1,730

1,730

1,730

1,720

1,720

1,700

1,680

1,680

1,680

1,650

1,600

1,550

1,510

1,480

1,480

1,480

1,470

1,450

1,450

1,500

1,530

Suspended sediment

Mean 

percent

0.10

.16

.09

.04

.04

.04

.03

.03

.04

.03

.03

.02

.03

.02

.03

.02

.02

.02

.02

.02

.02

.02

.02

.02

.03

.02

.03

.02

.02

.03

Tons per 

day

4,970

7,860

4,330

1,910

1,910

1,910

1,420

1,400

1,890

1,400

1,400

934

1,390

929

1/380

907

907

907

891

864

837

815

799

799

1,200

794

1,170

783

810

1,240

48, 760

December

Mean discharge 

(secondfeet)

1,560

1,620

1,630

1,620

1,580

1,550

1,550

1,630

1,670

1,680

1.700

1,700

1,700

1,700

1,680

1,770

1,750

1,670

1,560

1,500

1,400

1,260

1,190

1,160

1,080

938

1,050

1,110

976

902

819

Suspended sediment

Mean 

percent

0.03

.01

.02

.02

.02

.02

.02

.02

.03

.03

.02

.02

.02

.02

.04

.05

.04

.02

.02

.02

.02

.02

.03

.03

.02

.03

.02

.04

.02

.03

.04

Tons per 

day

1,260

437

880

875

853

837

837

880

1,350

1,360

918

918

918

918

1,810

2,390

1,890

902

842

810

756

680

964

940

583

760

567

599

527

731

885

29,880

1940

!-.-__

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-

January

786

786

976

1,320

1,720

1,870

1,960

1,850

1,910

1,890

1,780

1,750

1,840

1,850

1,700

1,430

1,220

976

539

690

866

1,110

1,150

1,020

963

1,000

1,000

1,070

1,250

1,430

1,450

0.02

.02

.01

.01

.02

.03

.04

.02

.02

.03

.02

.02

.03

.03

.03

.05

.01

.01

.02

.01

.01

.01

.05

.01

.01

.01

.01

.02

.02

.03

Monthly load (tons)__

424

424

264

356

929

1,515

2,120

999

1,030

1,530

961

945

1,490

1,500

1,380

1,930

329

264

(')

373

234

300

310

551

260

270

270

289

675

772

.1, 170

23, 900

February

1,400

1,620

1,630

1,680

1,670

1,670

1,730

1,720

1,750

1,730

1,720

1,700

1,650

1,650

1,720

1,720

1,620

1,560

1,650

1,650

1,630

1,680

1,680

1,620

1,630

1,730

1,770

1,820

1,890

0.02

.02

.02

.02

.02

.02

.03

.02

.02

.02

.02

.02

.02

.02

.02

.02

.01

.01

.01

.01

.01

.01

.01

.01

.01

.01

.02

.02

.02

756

875

880

907

902

902

1,400

929

945

934

929

918

891

891

929

929

437

421

446

446

440

454

454

437

440

467

956

983

1,020

22, 320

March

2,030

2,670

3,810

4,710

4,240

4,240

4,550

4,400

3,950

3,400

3,270

3,140

3,140

3,140

2,900

2,780

2,670

2,670

2,560

2,670

2,670

2,670

2,780

2,900

2,900

2,780

2,900

3,020

3,270

3,540

3,810

0.04

.08

.31

.48

.40

.28

.39

.26

.23

.27

.27

.24

.20

.17

.15

.15

.10

.09

.08

.09

.09

.08

.09

.11

.11

.12

.22

.22

.24

.26

.28

2,190

5,770

31, 900

61,000

45,800

32, 100

47,900

30. 900

24,500

24,800

23,800

20,400

17, 000

14, 400

11, 700

11,300

7,210

6,490

5,530

6,490

6,490

5,770

6,760

8,610

8,610

9,010

17, 200

17, 900

21,200

24,800

28,800

586, 300

1 Less than 60 tons per day.
QUANTITIES OF SUSPENDED SEDIMENT 107

TABLE 15. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Green River at gaging station near Green River, Utah. 

Oct. 1, 1989, to Sept. 30, 1941 Continued

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....

26....

26....

27 

28--

29-...

30-...

31

April

Mean discharge 

(secondfeet)

3,950

3,950

3,810

3,540

3,400

3,540

3,810

3,950

3,670

3,400

3,400

3,540

3,540

3,270

3,140

3,140

3,020

2,900

2,900

3,400

4,240

4,400

4,400

4,550

5,370

6,080

6,270

6.460

7,850

8,920

Suspended sediment

Mean 

percent

0.30

.28

.32

.38

.32

.26

.22

.23

.20

.16

.14

.14

.13

.12

.11

.10

.10

.07

.07

.08

.16

.22

.19

.21

.36

.43

.41

.37

.54

.70

Monthly load (tons)--

Tons per 

day

32, 000

29,900

9.9 nnn Oi>} tJ\f\J

36, 300

29,400

24,800

22, 600

24, 500

19, 800

14, 700

12,800

13, 400

12, 400

10, 600

9,330

8,480

8.150

5,480

5,480

7,340

18, 300

26, 100

22,600

25,800

52,200

70,600

69. 400

64,500

114,000

169, 000

992. 900

May

Mean discharge 

(secondfeet)

8 Q9n 

, o£i\J

8,700

8

(\fi{\ t UDU

7 240

6,270

5,720

6,270

9,140

10, 800

10,600

10, 400

10, 800

12, 400

13, 600

14, 100

15, 100

15, 700

15, 100

14,600

15, 100

15, 700

14, 100

13, 600

13, 100

12, 400

11, 600

10, 800

10, 600

10, 800

11, 100

12, 100

Suspended sediment

Mean 

percent

0.68

.52

00 

. DO

Of) 

. O\)

.26

.22

.22

.39

.52

.43

.38

.37

.46

.54

.48

.46

.48

.40

.33

.3,8

.33

.35

.29

.26

.25

.22

.22

.16

.13

.22

.25

Tons per 

day

164 000 122! ooo

on 7nn <W, /UU

58 600 44' ooo

34, 000

37,200

96,200

152, 000

123, 000

107, 000

108, 000

154, 000

198, 000

183, 000

188, 000

204, 000

163, 000

130, 000

155, 000

140, 000

133, 000

106. 000

92, 000

83, 700

68,900

64,200

45, 800

37,900

65, 900

81, 700

3, 423, 000

June

Mean discharge 

(secondfeet)

19 J-jij ann OUU

13,400

13, 100

13, 600

13, 600

13, 400

1 14, 9 son OUU

12, 100

11 600

10! 600

9,600

9,140

8,480

7,440

6,650

6,460

6,270

6,080

5,900

5 540

5,370

5,370

5,040

5,040

5,040

5,200

5,040

4,550

<t,840

4,100

Suspended sediment

Mean 

percent

0.24

.31

on 

. oU

oe 

. OO

00 

. OO

.28

.27

99 . £»£»

. £i£t 99

.19

.16

.16

.12

.11

.10

.11

.05

.06

.07

.06

.06

.07

.04

. .04

.04

.05

.05

.05

.02

.14

Tons per 

day

09 nnn o*» fvu

119 fiflfl 11 A, UVU

106, 000

128 000

i Ld£f °. 9 nnn vUU

101, 000

93,300

n orm 

, yuu

CO QAfl OO» oUU

54,400

4'l, 500

39,500

27,500

22, 100

18, 000

19,200

8,460

9,850

11,200

8,970

8,700

10,200

5,440

5,440

5,440

7,020

6,800

6,140

2,610

15,500

1, 230, 000

1940

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..-

July

3,540

3,400

3,020

2,780

2,560

2,410

2,280

2,180

2,180

2,140

2,030

1,910

1,820

1,700

1,560

1,530

1,430

1,320

1,390

1,450

1,300

1,190

1,110

1,040

1,000

950

938

950

926

902

890

0.08

.08

.10

.03

.05

.10

.09

.06

.06

.03

.02

.02

.01

.01

.01

.01

.06

.01

.01

.01

.06

.10

.11

.06

.06

.05

.04

.02

.04

.02

.02

Monthly load (tons) ..

7,650

-7,340

8,150

2,250

3,460

6,510

5,540

3,530

3,530

1,730

1,100

1,030

491

459

421

413

2,320

356

375

392

2,110

3,210

3,300

1,680

1,620

1,280

1,010

513

1,000

487

481

73, 740

August

878

830

808

808

742

720

819

775

710

700

690

680

680

640

630

620

611

620

620

660

710

650

630

660

742

950

1,050

1,360

1,550

1,310

1,090

0.01

.02

.02

.02

.02

.01

.04

.12

.09

.04

.02

.02

.02

.02

.02

.02

.02

.02

.02

.02

.03

.08

.06

.05

.11

.22

3.48

.56

.34

.22

.50

237

448

436

436

401

 194

885

2,510

1,720

756

373

367

367

346

340

335

330

335

335

356

575

1,400

1,020

891

2,200

5,640

98,700

20,600

14,200

7,780

14, 700

179, 200

September

926

902

830

1,280

1,050

890

854

866

819

797

786

775

819

1,080

1,250

1,260

1,120

2,660

1,960

2,010

1,870

1,650

1,850

1,960

1,700

1,620

1,560

1,470

1,910

2,320

0.48

.28

.14

.73

4.03

.61

.24

.10

.06

.03

.02

.02

.04

.05

4.95

3.74

.97

4.38

3.98

2.64

1.92

1.87

1.06

.92

.46

.42

1.48

.64

1.30

3.55

12.000

6,820

3,140

, 25. 200

114, 000

14,700

5,530

2,340

1,330

646

424

418

885

1,460

167, 000

127,000

29,300

315. 000

211, 000

143, 000

96,900

83, 300

52, 900

48, 700

21, 110

18, 400

62, 3uO

25, 400

67,000

222, 000

1, 879, 000

 ^5606 47-
108 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 15. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Green River at gaging station near Green River, Utah, 

 Oct. 1, 1939, to Sept. SO, 1941 Continued

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 

October

MeaoQ discharge 

(secondfeet)

2,280

4,210

3,960

3,030

3,400

3,760

3,560

3,430

2,970

2,850

2,630

2,500

2,410

2,340-

2,240

2,140

2,110

2,060

2,000

1,930

1,860

1,810

1,810

1, 770.

1,730

1,730

2,110

1,950

1,840

2,040

1,930

Suspended sediment

Mean 

percent

1.46

2.48

2.99

2.39

1.88

1.64

1.54

1.36

1.68

1.44

1.34

1.12

.65

.53

.35

.26

.22

.18

.18

.17

.32

..13

.12

.11

.10

.16

.22

.80

.26

.24

.15

Monthly load (tons).

Tons per 

day

89,900

282,000

320,000

196,000

173,000

166,000

148,000

126,000

135, 000

111,000

95, 200

75, 600

42, 300

33, 500

21,200

15,000

12,500

10,000

9,720

8,860

16, 100

6,350

5,860

5,260

4,670

7,470

12, 500

42,100

12, 900

13, 200

7,820

2,205,000

November

Mean discharge 

(secondfeet)

1,810

1,770

1,810

1,860

1,860

1,950

9 &r fun \ri\}

2,090

2,060

2,060

2,060

2,060

2,090

2,040

1,950

1,810

1,730

1,730

1,810

1,700

1,860

2,020

2,110

2,060

1,930

1,950

1,880

1,640

1,660

Suspended sediment

Mean 

percent

0.18

.30

.14

.12

.10

.10

.11

.12

.11

.14

.11

.12

.10

.09

.08

.07

.07

.08

.10

.07

.10

.10

.11

.10

.07

.08

.06

.09

.06

____ _ .-_...... _

Tons per 

day

8,800

14,340

6,840

6,030

5,020

5,260

6,060

6,770

6,120

7,790

6,120

6,670

5,640

4,960

4,210

3,420

3,270

3,740

4,890

3,210

5,Q20

5,150

6,270

5,560

3,650

4,210

2,540

3,990

2,690

i 162, 200

December

Mean discharge 

(secondfeet)

1,560

1,620

1,840

2,020

2,140

2,140

2,160

2,180

2,210

2,210

2,140

2,000

2,040

1,540

1,180

664

734

776

790

546

508

720

1,130

1,360

1,620

1,790

1,840

1,840

1,620

1,640

1,680

Suspended sediment

Mean 

percent

0.06

.05

.06

.10

.09

.09

.09

.10

.06

.09

.08

.07

.04

.06

.10

.02

.03

.04

.04

.04

.04

.08

.12

.10

.11

.12

.12

.08

.06

.07

.06

..-.. ___ ------ ....

Tons per 

day

2,530

2,190

2,980

5,450

5,200

5,200

5,250

5,890

3,580

5,370

4,620

3,780

2,200

2,500

3,190

359

596

838

853

590

540

1,560

3,660

3,670

4,810

5,800

6,960

3,470

2,620

3,100

2,720

101, 100

1941

1 ...

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12....

13 

14 

16 

16 

17 .

18 

19. 

20 

21....

22 .

23....

24 

26 

26....

27.,..

28. 

29 

30 

31 .

January

1,790

1,970

1,860

2,160

1,860

1,700

1,380

1,360

1,310

1,250

1 1, 360

1,520

1,520

1,580

1,580

1,680

1,580

1,640

1,790

1,810

1,730

],420

1,460

1,420

1,640

1,580

1,770

1,860

1,640

1,640

1,660

0.04

.04

.09

.03

.06

.06

.03

.02

.02

.03

.03

.03

.01

.02

.03

.02

.04

.05

.04

.04

.06

.04

.05

.06

.05

.05

.06

.03

.04

.05

.05

Monthly load (tons).-

1,930

2,130

4,520

1,750

3,010

2,750

1,120

734

707

1,010

1,100

1,230

410

853

1,280

907

1,710

2,210

1,930

1,960

2,800

1,530

1,970

2,300

2,210

2,130

2,870

1,510

1,770

2,210

2,240

56,790

February

1,500

1,540

1,520

,770

,660

,660

,640

,600

1,460

1,420

1,480

1,580

1,600

1,620

1,640

1,700

1,840

2,000

2,280

2,470

2,580

2,830

3,000

3,430

4,360

4,320

4,580

4,470

0.03

.02

.02

.02

.04

.05

.04

.04

.02

.03

.02

.04

.05

.04

.05

.05

.06

.19

.18

.32

.34

.30

.33

.85

.89

.81

.74

.58

1,210

832

821

956

1,790

2,240

1,770

1,730

788

1,150

799

1,710

2,160

1,750

2,210

2,300

2,980

10, 300

11,100

21, 300

23,700

22,900

26,700

78,700

105, 000

94,500

91,500

70, 000

582, 900

March

4,510

4,580

4,400

4,470

4,430

3,760

3,660

3,660

3,400

3,090

2,850

2,600

2,520

2,410

2,240

2,140

2,040

2,000

2,110

2,310

2,440

2,500

2,740

3,660

5,480

5,440

5,320

5,240

4,960

4,140

3,830

0.51

.57

.56

.46

.61

.56

.52

.52

.40

.33

.40

.34

.21

.18

.14

.13

.09

.09

.10

.37

.36

.35

.43

.64

.80

.70

.89

.88

.91

.75

.50

62, 100

70, 500

66, 500

55,500

73,000

56,900

51,400

51,400

36, 700

27,500

30,800

23,900

14,300

11,700

8,470

7,510

4,960

4,860

5,700

23, 100

23, 700

23,600

31, 800

63,200

118, 000

103, 000

128, 000

124, 000

122, 000

83,800

51,700

1, 560, 000

1 Includes estimates for missing days.
QUANTITIES OF SUSPENDED SEDIMENT 109

TABLE 15. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the Green River at gaging station near Green River, Utah, 

Oct. 1, 1939, to Sept. 30, 1941 Continued.

1941

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

Mean discharge 

(secondfeet)

3,790

3,790

4,210

4,730

5,560

6,600

6,960

7,180

6,640

6,330

6,160

5,860

5,480

5,400

5,360

5,280

5,160

5,730

5,660

5,480

5,480

5,120

4,770

4,360

4,000

3,830

3,930

4,400

5,160

5,650

Monthly lof

Suspended sediment

Mean 

percent

0.41

.32

.35

.36

.48

.73

.87

.72

.60

.52

.46

.42

.31

.32

.35

.32

.30

.33

.34

.26

.29

.24

.19

.22

.21

.19

.24

.22

.30

.32

id (tons) __

Tons per 

day

42,000

32,700

39,800

46,000

72,100

130,000

164, 000

140, 000

108,000

88,900

76,500

66,500

45,900

46,700

50,700

45,600

41,800

51,100

51,900

38,500

42, 900

33,200

24,500

25, 900

22,700

19. 600

25,500

26, 100

41,800

48,800

1,690,000

May

Mean discharge 

(secondfeec)

6,550

7,740

8,450

9,470

10,100

11,200

14, 000

18,600

17, 300

14,300

13, 700

14,700

17, 700

20,200

20,000

25,100

25,700

25,400

23,900

23,300

22,900

22,100

20,600

20, 700

23,000

23,600

25,500

25, 400

26, 700

26,800

26,200

Suspended sediment

Mean 

percent

0.41

.59

.76

.78

.91

.94

1.25

1.33

1.08

.87

.89

-.97

1.01

1.08

.98

.90

.78

.63

.72

.58

.63

.61

.53

.44

.77

.88

2.01

.69

.44

.44

.36

Tons per 

day

72,500

123,000

173,000

199,000

248,000

284,000

472,000

668,000

504,000

336, 000

329,000

385, 000

483,000

589,000

529,000

610,000

541.000

432,000

465, 000

365,000

390,000

364,000

295,000

246,000

478,000

561,000

1,384,000

473, 000

317,000

318,000

 >55, 000

12, 890, 000

June

Mean discharge 

(secondfeet)

25,000

23.400

21,600

20,000

18,900

18, 200

19,300

21,100

21,300

21,100

20,400

20,400

20, 500

21,500

20, 500

19,000

18,500

18,700

19,200

20,300

20,000

20,200

19,900

19.000

18,000

16, 900

15,600

14,100

13, 200

12, 100

Suspended sediment

Mean 

percent

0.38

.44

.38

.39

.26

.29

1.34

1.08

1.90

.71

.51

.39

.31

.33

.30

.39

.30

.26

.27

.31

.23

.25

.28

.20

.23

.14

.21

.17

.20

.18

__ --_...-... _ -----

Tons per 

day

256,000

278,000

222,000

211,000

133, 000

142,000

698,000

615, 000

518, 000

404,000

281,000

215,000

172,000

192,000

166,000

200,000

150,000

] 31, 000

140,000

170,000

124,000

136,000

150,000

123, 000

112,000

63,900

88,500

64,700

71,300

58,800

6,286,000

1941

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.-..

July

11,300

10,700

9,970

9,030

8,450

7,970

7,690

7,180

6,600

6,160

5,650

5,400

5,280

5,040

5,200

5,400

5,080

4,850

4,850

5,520

4,660

4,580

4,470

3,960

3,630

3.660

3,930

3,7flO

3,660

3,530

3,530

Momthly Ic

0.12

.14

.12

.13

.12

.12

.10

.09

.10

.12

.14

.08

.10

.08

.08

.11

.17

.10

.33

' .39

.25

.16

.11

.10

.09

.08

.08

.10

.12

.16

.10

ad (ton). .

36,600

40,400

32, 300

31, 700

27,400

25,800

20,800

17,400

17,800

20,000

21,400

11,700

14,300

10, 900

11, 200

16, 040

23,300

13, 100

43,200

58,100

31,500

19,800

13,300

10,700

8,820

7,990

8,490

10,200

11,900

15,200

9,530

640, 800

August

3,400

3,210

3,240

3,240

3,360

2,880

2,740

2,520

2,630

3,400

4,850

5,900

4,100

3,560

3,630

6,110

5,770

7,320

6,460

5,400

7,140

6,460

5,650

4,770

4,280

3,860

3,630

3,430

3,470

3,760

4,690

0.09

.07

.05

.05

.07

.07

.04

.19

.09

.31

1.28

.70

1.93

2.39

1.07

.85

.59

3.97

1.96

1.88

2.06

1.64

2.62

1,56

.99

1.85

.72

.58

.31

.30

1.56

8,260

6,070

4,370

4,370

6,350

5,440

2.960

12,900

6,390

28, 500

168,000

112, 000

214,000

230, 000

105,000

140, 000

91,900

785, 000

342, 000

274,000

397, 000

286,000

400,000

201,000

114, 000

88,600

70,600

53, 700

29,000

30,500

198, 000

4, 416, 000

September

4,690

4,180

3,630

3,310

3,090

2,970

2, 740

2,550

2,440

2,310

2,180

2,110

2,300

2,830

2,580

2,550

2,800

2,970

2,880

2,690

2,550

2,580

2,580

3,730

5,440

4,320

3,360

3,120

3,120

2,910

0.49

.50

.55

.48

,56

.57

.66

.24

.17

.15

.16

.15

.24

.67

1.48

.46

.30

.21

.36

.50

.26

.55

.26

.30

.94

1.58

.98

.69

.39

.16

62,000

56,400

53,900

42,900

46,700

45,700

48,800

16,500

11,200

9,360

9,420

8,550

16,200

51,200

103,000

31,700

22,700

16,800

28,000

36,300

17,900

38,300

18,100

30,200

138,000

184,000

88,900

58, 100

32,900

12,600

1, 336, 000

i Estimated.
110 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 16. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment 

in the San Juan River at gaging station near Bluff, Ltah, Aug. 13 to Sept. 21, 1928

Date

1988 

Aug. 13 _

Aug. 14... ..........

Aug. 15 . 

Aug. 16...... ... ....

Aug. 17. 

Aug. 18 

Aug. 20--..--.--- ...

Anf* 91

Aug. 22... ... ... . 

Aug. 23 

Aug. 24 __ ....

Aug. 26. 

Time of collection

10:00 a. m_ _____

9:30 a. m. _____ . 

11:00 a. m_ _

11:45 a. m... .....

3:45 p. m__ _____

4:30 p.m..... _ ....

6:30 a. m. ______ 

9:00 a. m_. _____

11:30 a.m. _

2:00 p. m _______

4:30 p. m ___ .....

2:00 p. m___ . .. ..

7:00 a.m.. ..........

8:00 a.m. ...........

8:00 a. m._ ____ ...

12:00 m_ ......... .

4:00 p. m _______

8:00 a. m. ...........

12:00 m_. ...........

8:00 a. m. ...........

12:00 m_... ..........

8:00 a. m_ ........ 

12:00 m_._.__ ........

6:30 a. m..... _ .... 

12:00 m_- _ ........

7:30 p. m ______ .

5:30 a. m. ...........

9:00 a. m. ...........

2:00 p. m ............

8:30 a. m_. ..........

5:30 a. m_...__ _ ...

12:30 p. m ...........

7:00 t). m. ____ ...

Mean 

daily 

discharge 

(sec.-ft.)

1,580 

1,280

760

747

774 

650

612 

482

482 

428 

499

669

450 

320

Suspended sediment

Number 

of samples

9 

9

8

5 

4 

2 

3 

2 

2 

2

2 

3 

2 

3 

3 

3

3 

3 

3 

2 

3

3 

3

3 

2 

3

3 

2 

3

3 

8 

2 

3

3 

2 

1

3 

3 

3

3 

3 

3 

3 

3

3 

3 

3 

3 

3 

3

3 

3 

3 

3

3

3 

3

Mean percent at 

sampling 

period

1.10 

4.11 

5.13

2.57 

2.41 

2.34 

2.30 

2.44 

2.62 

2.27

2.09 

2.12 

1.89 

1.89 

1.80 

1.82

1.98 

1.79 

1.75 

1.62 

1.58

1.54 

1.70

1.07 

1.08 

1.06

1.88 

2.02 

1.92

1.74 

1.70 

1.72 

1.93

1.77 

1.54 

1.40

1.13 

1.06

.87

.89 

.81 

.83 

1.27 

6.61

13.6 

10.9 

9.38 

7.14 

5.99 

5.37

2.97 

2.99 

2.48 

2.21

1.67 

1.60 

1.28

Mean 

daily 

percent

3.38 

2.44

1.94

1.75

1.62 

1.08

1.92 

1.76

1.68 

1.02 

1.95

 8.73 

2.66

*

1.52

Tons per 

day

144,000 

84,200

39,800

35,200

33,800 

18,900

31, 700 

22,900

21,800 

11,800 

26.200

158,000

32,300 

13,100
QUANTITIES OF SUSPENDED SEDIMENT 111

TABLE 16. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment in 

the San Juan River at gaging station near Bluff, Utah, Aug. 18 to Sept. 21, 1928 

Continued

Date

1998 

Aug. 27.............

Aug.28_-....._...__ 

Aug. 29.............

Aug. 30 .............

Aug. 31.. ___ .....

Sept. 1.. _ .........

Sept. 2i... __ .. ... 

Sept. 3.... __ . _ ..

Sept. 4.............. 

Sept. 5..............

Sept. 6......... __ .

Sept. 7... _ . ....... 

Sept. 8. .............

Sept. 9....... ....... 

Sept. 10........ _ ..

Time of collection

1:30 p. m ............ 

5:00 p. m ............

9:00 a. m. ........... 

1:00 p. m... .........

5:00 p. m ............

6:00 a. m.... __ .... 

9:00 a. m. ...........

12:00 m... ....... ...

3:15 p. m... .........

6:00 p. m ...........

6:00 a. m. ...........

12:00 m ... .......

6:00 a. m..... .......

10:30 a.m.. _ . __ .

4:00 p. m ............

5:00 p. m ............

6:30 p. m .. _ . __ .

9:00 p. m ............

6:00 a. m ___ . __ . 

10:30 a. m. ..........

4:30 p. m ............

7:00 a. m ............ 

2:00 p. m ............

4:30 p. m __ . __ ..

6:00 a. m. ...........

12:00 m... _ ........

8:00 a.m. ........... 

9:00 a. m ............

4:30 p. m ............

8:45 a. m. ...........

5:00 p. m ............

8:00 a. m ............ 

12:00 m... ...........

8:00 a. m.. .......

12:00 m.... .......

1:00 pm.._. .........

2:00 p. m ............

5:00 p. m .. .......

6:00 a. m ............ 

4:30 p. m ............

8:30 a. m.._ _ . ..... 

1:30 p.m... .........

3:15 p. m ............

5:45 p. m ............

Mean 

daily 

discharge 

(sec.-ft.)

1,000 

850

980

970 

2,020

1,180 

1,140 

1,580 

1,270 

1,020

900 

760

695

695 

662

Suspended sediment

Number 

of samples

3 

3

3 

3 

3

8 

3 

3 

3 

S 

3 

3

3 

3 

3

8 

10 

2 

3 

3 

7 

' 2

3 

3 

3

2 

3 

3

3 

9 

3

3 

3 

3

3 

9 

3

7 

3

3 

3 

3

3 

3 

3 

6 

5

'3 

3

3 

3 

3 

3

Mean percent at 

sampling 

period

3.14 

2.61

2.51 

2.52 

2.15

1.92 

1.71 

1.35 

2.89 

3.21 

2.34 

1.49

1.71 

1.67 

1.48

2.12 

1.79 

3.36 

5.64 

6.27 

5.37 

5.14

3.13 

2.97 

2.47

2.62 

2.45 

2.14

2.41 

2.59 

1.90

1.55 

1.52 

1.46

1.15 

1.01 

1.06

.69 

.66

.78 

1.08 

.55

.48 

.41 

.49 

.35 

.43

.33 

.34

.60 

.63 

.61 

.58

Mean 

daily 

percent

2.88 

2.37

2.09

1.61 

2.51

2.86 

2.48 

2.41 

1.51 

1.05

.68 

.81

.42

.34 

.60

Tons per 

day

77, 700 

54,300

55,200

42, 100 

137,000

91,000 

76,200 

103,000 

51,700 

28,900

16,500 

16,600

7,880

6,360 

10,700
112 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 16. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment in 

the San Juan River at gaging station near Bluff, Utah, Aug. IS to Sept. 21, 1928 

Continued

Date

1988 

Sept. 11.... _ . .....

Sept. 12.............

Sept. 13.. ...........

Sept. 14.. ___ ....

Sept. 15... ..........

Sept. 16 . - 

Sept. 17 .... ......

Sept. 18.. __ . __ .

Sept. 19. ............

Sept. 20... ..........

Sept. 21 ..........

Time of collection

8:30 a. m _____ ... 

10:00 a. m ....... .

5:00 p. m ______

6:45 a. m.. .......... 

6:45 a. m.. .. ...

6:00 a. m .. .

4:30 p.m. _____ .

8:00 a.m.. __ .....

8:30 a. m.- ____ ..

9:00 a. m.. _____ .

12:00 m..... __ .....

5:00 p. m .... .....

6:30 a. m_. ......

4:30 p. m.... _ . _ .

9:00 a. m ............ 

9:30 a. m. ...........

4:30 p. m ............

9:00 a.m...... _ ...

9:00 a. m._ ..........

Mean 

daily 

discharge 

(sec.-ft.)

646

682

628 

534

694

640 

472

472

444 

450 

411

Suspended sediment

Number 

of samples

3 

9 

3

3 

7 

3 

3

3 

3

3

7 

3

3 

3 

3

10 

3

3

7 

3

3 

8 

3

3 

3

3 

3

3

Mean percent at 

sampling 

period

0.38 

.31 

.25

.46 

.44 

.23 

.18

.29 

.28

'.29 

.35 

.32

.42

.36 

.34

.30 

.23

.30 

.29 

.21

.29 

.26 

.21

.23 

.23

.17 

.37

.24

Mean 

daily 

percent

0.31 

.36

.28 

.40

.37

.28 

.27

.26

.23 

.27 

.24

Tons per 

day

4,660 

6,660

3,990 

5,770

5,930

4,070 

3,430

3,320

2,750 

3,290 

2,670
QUANTITIES OF SUSPENDED SEDIMENT 113

TABLE 17. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment in 

the San Juan River at gaging station near Bluff, Utah, July 1 to Sept. SO, 1929

Date

1989 

July I..............

2

3 ___ .......

4-... ........

5... _ .......

July 6.. ......... ..

7--.. ......

8.... _ ... ...

9-.. .......

July 10-. ........

July 11-- . _ .... 

July 12.............

July 13.- ...... 

July 14... ____ ..

July 15...... .......

July 16- ... . .. 

July 17 ..........

July 18 _______ . 

July 19... ___ ....

July 20 _______ .

July 21... _____ . 

July 22.. ...........

July 23 _____ ... 

July 24... ___ ...

July 25.. ........... 

July 26 ______ ..

Time of collection

2:30 p. m ___ ... ... 

3:00 p. m ............

5:45 a. m. _ ... 

9:45 a.m.. .........

9:15 a. m. _ .. ......

8:15 a. m __ . _ . ...

8:15 a. m __ . _ . ...

7:40 p. m ............

8:00 a. m. . 

3:30 p. m ... .. 

6:35 a. m.. ... ... . 

12:45 p. m _.__ . 

6:30 a. m. ___ ....

8:15 a. m __ ........

7:20 a. m.. ...... . 

2:00 p. m ............

8:40 a. m ______

5:50 p. m. _ . __ ..

11:45 p. m ____ ..

8:50 a. m ............ 

2:00 p. m ............

7:15 p. m __ . ......

8:00 a. m ............

5:40 D. m .... ... 

Mean 

daily 

discharge 

(sec.-ft.)

4,340 

4,150

3,820 

3.750 

3,520

3,240 

3,040

2,540 

2,460

2,420

2,220 

2.310

2,620

2,560 

2,430

2,080 

2,100

2,000 

1,990

1,680

1,860 

2,140

2,990

3,030 

3,100 

3,460

Suspended sediment

Number of 

samples

-

3 

2

2

7 

6

2 

3

3

7 

3 

3

8 

3

7 

3 

3

8 

3

7 

3 

3 

3

7 

2 

3

3

7 

3 

3

7 

3 

3 

3 

3

7 

3 

3

6 

3 

3

7 

3 

3

Mean 

percent at 

sampling 

period

0.46 

.54

.52

3.59 

1.16

.67

.77

.65

.64 

.81 

.79

.64

.77

.51 

1.07 

.96

.89 

.68

.80 

.96 

.82 

1.19

.63 

.38 

.45

.44

.56 

.51 

.47

.43 

.61 

1.30 

1.31 

1.57

1.56 

1.42 

1.54

3.89 

1.79 

2.52

1.75 

1.80 

1.91

Mean daily 

percent

0.66 

.42 

.41 

.32 

.31

.29 

.31 

.25 

.29

.50

.52 

2.47

.73

.65 

.71

.67 

.75

.83 

.90

.54

.44 

.53

.92

1.52 

2.80 

1.80

Tons per 

day

77,300 

47,100 

42,300 

32,400 

29,500

25,400 

25,400 

17,100 

19,300

32,700

31,200 

154,000

51,600

44,900 

46,600

37,600 

42,500

44,800 

48,400

24,500

22,100 

30,600

74,300

124,000 

234,000 

168.000
114 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 17. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment in 

the San Juan River at gaging station near Bluff, Utah, July 1 to Sept. 30, 1929 

Continued

Date

1989 

July 27-- -

July 28-. -

July 29.- 

July 30 _ . .-. 

July 31... .

Aug. 1.- ----- 

Aug. 4 -.-

Aug. 7 - 

Aug. 8._ -

Aug. 9. ..... ....

Aug. 10 -

Aug. 11.-- -----

Aug. 13. - 

Allcr 14

Time of collection

7:20 p. m_. _ .... ...

6:30 p.m. ...... .

9*00 a m

ll:lSa. m. __-__ 

8:lSa. m. - --

8:20 a.m. _____ .

5:10 P. m.---. ..

Mean 

daily 

discharge 

(sec.-ft.)

5,090 

' 7,690

14,600 

11,100

10,300 

13,500

20,500 

11,800

12,600 

15,800

18,800

13,300 

11, 100

12, 200 

8,470

16,700 

38,300

19, 300 

9,270

Suspended sediment

lumber of 

samples

7 

3 

3

2 

3 

3 

3

3 

3 

3

3 

3 

3

2 

2

3 

3 

3 

1

3

9 

3 

3

1

3 

3 

2

3 

3 

3 

3 

3 

3

3

3

8

3 

3

3 

9 

3

3

3 

3 

3 

4

2 

2 

3

3 

3

Mean 

percent at 

sampling 

period

3.55 

7.31 

4.35

22.2 

15.7 

13.6 

8.69

13.8 

12.9

8.85

7.18 

5.48 

8.42

12.1 

9.12

6.09 

7.20 

7.95 

15.0

6.37

3.78 

3.38 

3.32

13.9

5.03 

5.42 

9.40

10.5 

13.6 

13.1 

10.4

5.77 

5.99

5.68

3.20 

4.62

5.47 

7.17

3.94 

3.12 

3.05

4.44

8.94 

7.76 

7.74 

6.94

6.20 

6.19 

6.39

3.41 

2.40

Mean daily 

percent

4.60 

14.4

11.8 

6.85

10.6

7.87

6.37 

3.61

13.9 

6.28

9.88

5.68 

4.24

6.32 

3.27

4.44

7.77

6.28 

2.91

Tons per 

day

632,000 

2,990,000

4,650,000 

2, 050, 000

2,950,000 

2, 870, 000

3, 530, 000 

1, 150, 000

4, 730, 000 

2,680,000

5,020,000

2,040,000 

1,270,000

2, 080, 000 

748, 800

2,000,000 

8, 040, 000

3, 270, 000 

728,000
QUANTITIES OF SUSPENDED SEDIMENT 115

TABLE 17. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment in 

the San Juan River at gaging station near Bluff, Utah, July 1 to Sept. 80,1929 

Continued.

Date

1929

Aug. 17. .........

Aug. 18... ...... .

Aug. 21. ......

Aug. 23-... ....

Aug. 24. --.------. ..

Aug. 25-... ... ...

Aug. 26... ..........

Aug. 27.... 

Aug. 28.... .........

Aug. 29...... .......

Aug. 30 _______ .

Aug. 31. ............

Sept. I... .....

Sept. 2..............

Sept. 3...... ....... .

Sept. 4.... __ .....

Sept. 5.... .......

Sept. 6.... ....

Sept. 7. ___ . _ .. 

Sept. 8....- .... .

Sept. 9.... _ ....... 

Sept. 10.. ._. _

Time of collection

5:40 p. m

3:10 p. m_____.__ _ .

4:05 p. m..__ ........

8:25 a. m. .........

8:40 a. m.. . .

4:10 p. m_

12:25 p. m _ . __ ..

2:25 p. m.... _ . ....

7:30a. m .........

11:20 a. m . ........

3:30 p. m... _ . .....

4:30 p.m............

8:00 a.m. _____ 

1:55 p. m ............

3:00 p. m ............

3:00 p. m ______ . 

8:45 a. m. ...........

Mean 

daily 

discharge 

(sec.-ft.)

7,080

5,780

5,120 

4,550 

4,320

3,580

3,380 

2,720

2,890 

2,660 

2,530

3,440

3,110 

2,560 

4,000 

6,850 

5,040 

5,600 

8,070 

13,100

11, 100 

8,070

7,010

6,220 

5,280 

4,800

Suspended sediment

Number of 

samples

3 

3 

9

3 

3

9 

9

9 

3

7 

3

9

9 

3

9

7

3 

3

9 

3

9 

3 

3 

3 

3 

3 

3

3 

3

3 

3 

3 

3

3 

3 

3 

3

3 

3 

3

9 

3

8

Mean 

percent at 

sampling 

period

1.62 

1.46 

1.30

1.16 

1.08

1.44 

.92

1.06 

.77

.84 

.80

.83

.92 

.82

.92 

1.10

.96 

.81

.99 

3.27

2.67 

1.57 

4.08 

5.38 

6.58' 

5.14 

7.46

7.88 

7.41

6.61 

5.93 

6.14 

6.00

4.21 

3.79 

3.86 

3.86

3.90 

3.64 

3.34

2.75 

1.71 

1.48

Mean daily 

percent

1.39

1.12

1.44 

.92 

.99

.83

.83 

.90

.92 

1.10 

.88

1.56

2.67 

1.57 

4.08 

- 5.38 

6.58 

. 5.14 

7.46 

7.65

6.17 

3.93

3.63

2.75 

1.71 

1.48

 Tons per 

day

266,000

175, 000

199,000 

113, 000 

115,000

80,200

75, 700 

66,100

71, 800 

79,000 

60, 100

145,000

224,000 

109,000 

441,000 

995, 000 

895, 000 

777,000 

1, 630, 000 

2,710,000

1,850,000 

856,000

687,000

462,000 

244,000 

192,000
116 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 17. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment in 

the San Juan River at gaging station near Bluff, Utah, July 1 to Sept. SO, 1929 

Continued

Date

1989 

Sept. 11.. _ ... _ ..

Sept. 12 .............

Sept. 13. ___ ... ...

Sept. 14.............

Sept. 15. ___ ...... 

Sept. 16.... _ ......

Sept. 17......... ....

Sept. 18.... _ . _ ..

Sept. 19.............

Sept. 20.... _ . .....

Sept. 21... __ . _ ..

Sept. 22.. __ .. _ ..

Sept. 23............. 

Sept. 24. ___ .. ... 

Sept. 25.............

26--...- ...-

27...-.- .-.

28 __ ,. _ ....

29... __ .......

30. .. ___ .

Time of collection

1:15 p. m ... ....

9:30 a. m ............

5:15 p. m _____ ^.

9:20 a.m. ...........

5:45 p. m ............

9:35 a.m. ....... _ .

5:45 p. m ............

10:10 a. m ____ ..

3:10 p.m.. ..........

10:05 a. m ..........

1:50 p. m. . .........

10:00 a.m. ......... 

4:00 p. m... .........

8:30 a. m ...........

2:00 p.m... _ ......

Mean 

daily 

discharge 

(sec.-ft.)

4,320

4,080 

4,190 

3,720

3,310 

3,030

2,720 

2,480

2,250 

4,180 

13,100

8,870 

20,000

21,500

14,000 

9,880 

7,580 

6,830 

6,040 

4,990

Suspended sediment

Number of 

samples ,

4 

3 

3

9 

3

7 

3

8 

3

7

7 

3

9

7 

3

3 

2

3 

3

3

3 

3

3 

3

3 

3 

3 

3 

3 

3

Mean 

percent at 

sampling 

period

1.27 

1.08 

1.13

1.13 

1.38

1.28 

1.19

1.02

.97

.83

.83 

.90

.65

.67

.75

.61

.44

40.8 

21.1

7.40

28.5 

14. a

8.32 

7.07

4.83 

2.42 

2.53 

2.53 

2.35 

1.52

Mean daily 

percent

1.17

1.19 

1.26 

1.00

.83

.85

.65 

.69

.61 

.44 

30.9

7.40 

21.2

7.69

4.83 

2.42 

2.53 

2.53 

2/35 

1.52

Tons per 

day

136,000

131,000 

143,000 

100,000

74,200 

69,500

47,700 

46,200

37,100 

49,700 

10,900,000

1,770,000 

11,400,000

4,460,000

1,830,000 

646,000 

518,000 

467,000 

383,000 

205,000
QUANTITIES OF SUSPENDED SEDIMENT 117

TABLE 18. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. 30, 1941

1929

Day

1 ...

2

3

4

5 .

6

7

8

9

10....

11 

12. ...

13 

14....

15 

16....

17. _

18....

19 

20 

21. _r.

22 

23 

24 

25 

26. 

27 

28. _

29 

30 

31 

October

Mean 

discharge 

(secondfeet)

4,300

3,810

3,410

3,410

2,910

2,680

2,510

2,350

2,350

2,200

2,290

2,290

2,120

2,290

2,020

2,350

2,240

2,180

2,040

1,920

1,850

1,710

1,580

1,530

1,520

1,460

1,420

1,370

1,360

1,350

1,400

Suspended sediment

Mean 

percent

2.15

' 2.80

2.12

3.39

1.74

.89

1.70

1.07

.68

1.01

.96

.81

.60

1.06

.80

.86

1.72

2.27

.78

.90

1.20

.74

.76

.63

.67

.70

.90

.39

1.35

.45

.41

Monthly load (tons)..

Tons per 

day

249,000

288,000

195,000

312, 000

137,000

64,400

115,000

67,800

43,100

60,000

59,300

50,000

34,300

65,500

43,600

54,500

104, 000

133,000

42,900

46,600

60,000

34,100

32,400

26,000

27,500

27,600

34,500

14,400

50,000

16,400

15,500

2,503,000

November

Mean 

discharge 

(secondfeet)

1,310

1,320

1,260

1,230

1,200

1,230

1,250

1,230

. 1,250

1,240

1,220

1,220

1,090

1,120

1,050

922

884

1,010

1,090

1,090

1,030

968

930

841

791

827

863

819

863

877

Suspended sediment

Mean 

percent

0.55

.37

.47

.44

.45

.42

.45

.21

.35

.42

.33

.64

.49

.61

.56

.46

.59

.52

.60

.58

.65

.54

.49

.71

.58

.64

.55

.40

.47

.65

Tons per 

day

19,400

13,200

16,000

15, 000

15, 000

14,000

15,200

6,970

11,800

14,000

10,900

21,100

14,400

18,400

15,900

11,400

14,100

14,200

17,600

17, 100

15,300

14,100

12,300

16,100

12,400

14,300

12,800

8,840

10,900

15,400

428,100

December

Mean 

discharge 

(secondfeet)

930

922

922

907

848

827

798

855

855

777

743

791

855

812

770

743

777

784

791

696

670

386

264

229

264

268

287

553

496

530

Suspended sediment

Mean 

percent

1.14

.66

.54

.71

.47

.47

.43

.37

.39

.39

.37

.38

.47

.33

.46

.46

.40

.29

.44

.45

.15

.10

.12

.11

.32

.54

.56

.40

.47

.52

Tons per 

day

28,600

16,400

13,400

17,400

10,700

10,500

9,250

8,530

8,990

8,170

7,410

8,110

10,800

7,230

9,550

9,220

8,380

6,130

9,390

8,450

2,710

1,040

853

679

2,280

3,900

4,330

5,970

6,290

7,430

J 257, 100

1930

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 

January

485

507

485

452

524

690

834

577

524

474

479

518

468

426

463

613

518

474

349

536

426

396

319

298

268

243

240

315

458

632

777

0.30

.22

 .35

.15

.39

.43

1.29

.27

.30

.50

.37

.26

.33

.52

.53

.22

.16

.36

.20

.19

.15

.22

.13

.17

.28

.26

.17

.32

.23

.36

.75

Monthly load (tons)..

3,920

3,010

4,580

1,830

5,510

8,000

29,000

4,200

4,240

6,390

4,780

3,630

4,160

5,970

6.620

3,640

2,240

4,600

1,880

2,750

1,720

2,350

1,120

1,370

2,020

1,700

1,100

2,720

2,840

6,140

15,700

149, 700

February

743

784

601

645

723

729

798

777

934

999

1,140

1,190

1,410

1,660

1,960

2,010

1,830

1,460

1,260

1,200

1,250

1,320

1,420

2,180

1,770

1,870

1,240

0.45

.77

.54

.55

.42

.42

.40

.38

.48

.53

.71

.92

.57

3.54

3.01

.77

.88

.60

.53

.46

1.00

.77

.89

.82

.93

.87

1.30

9,020

16,300

8,750

9,570

8,190

8,260

8,610

7,960

12,100

14,300

21,800

29,500

21,700

158,000

159,000

41,700

43,500

23,600

18,000

14,900

33,700

27,400

34,100

48,200

44,400

43,900

43,500

i 952, 900

March

1,050

1,060

907

798

757

870

930

960

975

930

892

900

877

907

960

1,090

1,260

1,630

1,980

1,590

1,300

1,170

1,150

1,250

 1,800

2,020

1,910

2,130

1,810

1,500

1,280

0.45

.62

.37

.36

.28

.51

- .-79

.83

.87

.75

.50

.43

.42

.44

.47

.39

.55

.77

1.16

.89

.65

.68

.45

.43

1.32

.95'

.71

1.14

.90

.58

.37

12,700

17,700

9,050

7,750

6,720

12,000

19,800

21,500

22,900

18,800

12,000

10,400

9,950

10,800

12,200

11,500

18,700

33,900

61,900

38,200

22,800

21,500

14,000

14,500

64,100

51,800

36,600

65,500

43,900

23,500

12,800

738,500

> Includes estimates for missing days.
118 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended 

sediment in the San Juan River at gaging station near Bluff, Utah, Oct. 1, 

1929, to Sept. 80, 1941 Continued

1930

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-...

April

Mean 

discharge 

(secondfeet)

1,270 

1,360 

1,470 

1,500

2,930 

4,340 

5,490 

5,920

6,000 

5,740 

5,090 

4,640 

4,860

5,330 

5,090 

4,480 

3,640 

3,260

3,450 

4,100 

5,280 

6,310 

6,910

6,910 

7,200 

6,090 

5,660 

5,170

Suspended sediment

Mean 

percent

.0.71 

.99 

1.03 

.63

1.77 

2.33 

1.44 

1.56

1.22 

1.57 

1.22 

1.24 

1.27

1.31 

.98 

1.22

.77 

.82

.95 

1.19 

1.30 

1.47 

1.33

1.15 

1.19 

1.23 

.92 

.81

Monthly load (tons) _ .

Tons per 

day

24,300 

36,300 

40,800 

25,500

140,000 

273,000 

213,000 

249, 000

197,000 

243, 000 

167, 000 

155,000 

166, 000

188,000 

135,000 

147,000 

75,600 

72,100

88,400 

132, 000 

185,000 

250,000 

248,000

214,000 

231,000 

202,000 

140,000 

113,000

'4,451,000

May

Mean 

discharge 

(secondfeet)

4,560 

4,270 

4,270 

5,330 

5,580

4,640 

3,920 

3,380 

3,130 

2,890

2,600 

2,490 

2,380 

2,220 

2,100

2,160 

2,950 

4,130 

3,780 

3,380

2,950 

2,890 

4,940 

5,740

5, 090 

6,270 

6,820 

7,880 

8,280 

10,600

Suspended sediment

Mean 

percent

1.01 

.74 

.99 

1.28 

1.34

.93 

.80 

.76 

.68 

.72

.70 

.51 

.47 

.63 

.45

.30 

.86 

1.29 

.74 

.55

.43 

4.14 

1.16 

1.85

.64 

.75 

.81 

1.01 

.75 

.92

Tons per 

day

124, 000 

85, 200 

114,000 

184, 000 

202,000

116, 000 

84,600 

69, 300 

57, 400 

56, 100

49, 100 

34,200 

30, 200 

37,700 

25,500

17,500 

68, 400 

144,000 

75, 400 

50,100

34,200 

323,000 

155,000 

286,000

87,900 

127,000 

149,000 

215,000 

» 167,000 

263,000

13,582,000

June

Mean 

discharge 

(secondfeet)

10,400 

10,400 

7,200 

5,920 

5,490

5, 580 

6.360 

8,080 

8,490 

8,380

7,980 

7,380 

7,380 

7,480 

7,380

6,540 

5,660 

5,170 

4,940 

5,010

4,340 

4,130 

3,990 

. 3, 710 

3,380

2,710 

2,320 

2,100 

1,900 

1,730

Suspended sediment

Mean 

percent

1.75 

1 59 

1.21 

.78 

.74

.61 

.74 

.94 

.92 

.83

.73 

.84 

1.17 

.93 

.78

.80 

.85 

.65 

.58 

.63

.51 

.45 

.59 

.34 

.60

.43 

.46 

.39 

.41 

.28

Tons per 

day

491,000 

446, 000 

235,000 

125,000 

110,000

91, 800 

127, 000 

205,000 

211, 000 

188,000

157,000 

167,000 

233, 000 

188, 000 

155,000

141, 000 

130, 000 

90,600 

77,300 

- 85, 100

69,700 

50,100 

63,500 

34,000 

54,700

31,400 

28,800 

22,100 

21,000 

13,100

4, 032, 000

1930

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....

July

1,600

1,320

1,150

1,050

922

855

743

716

664

710

952

4,480

1,600

2,270

2,270

1,420

1,410

2,380

2,490

4,710

3,850

5,170

5,660

5,010

4,130

 3,320

2,890

2,770

5,010

4,060

4,940

0.28

.21

.25

.20

.16

.18

.23

.16

.16

.24

4.04

6.59

18.4

10.3

10.2

4.10

2.96

3.87

6.46

8.87

8.24

8.61

5.48

3.56

2.58

2.21

1.82

1.94

4.38

3.08

5.47

Monthly load (tons) . .

12,100

7,480

7,750

5,660

3,980

4,150

4,610

3,090

2,870

4,600

104,000

796,000

792,000

633, 000

626, 000

157,000

113,000

248, 000

434, 000

1, 130, 000

856,000

1, 200, 000

837, 000

481,000

287, 000

198, 000

142,000

145,000

592, 000

337,000

729,000

10, 890, 000

August

3,990

4,130

4,200

3,640

3,920

2,170

2,490

3,320

13,900

11,400

15,800

12,400

8,910

5,490

4,130

3,520

3,070

2,600

2,380

2,050

1,800

1,420

1,310

1,050

900

827

777

729

696

607

501

_----.._._-

6.14

3.40

4.51

3.00

16.6

6.51

2.58

2.66

23.0

11.2

14.7'

10.1

7.81

6.55

3.60

2.35

1.57

1.29

.94

.87

.65

.66

.54

.45

.43

.55

.79

.39

.41

.44

.32

661,000

379,000

511, 000

295, 000

1,750,000

476,000

173,000

238, 000

8, 620. 000

3, 430, 000

6, 270, 000

3, 370, 000

1,880,000

970,000

401,000

223,000

130,000

90,500

60,300

48,100

31,600

25,300

19,100

12,700

10, 400

12,300

16,600

7,670

7,700

7,200

4,320

30,130,000

September

421

381

381

381

431

607

812

798

651

577

507

501

441

426

411

377

354

354

363

319

323

319

315

298

287

290

401

463

406

447

-----------

0.31

.24

.21

.25

1.52

2.27

2.66

2.19

1.06

.69

.68

.60

.47

.40

.34

.35

.32

.36

.36

.28

.30

.24

.23

.21

.20

.24

.30

.41

.33

.40

_ -----.-

3,520

2,470

^ 2,160

2,570

17,700

37,200

58,300

47, 100

18,600

10,700

9,300

8,110

5,590

4,600

3,770

3,560

3,060

3,440

3,520

2,410

2,610

2,060

1,950

1,690

1,550

1,880

3,240

5,120

3,610

4,800

276, 200

1 Includes estimates for missing days.
QUANTITIES OF SUSPENDED SEDIMENT 119

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. 30, 1941 Continued

1930

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- 

October

Mean 

discharge 

(secondfeet)

1,190

715

427

508

550

508

484

484

484

400

427

438

490

606

775

673

645

600

574

593

568

556

532

544

556

496

496

496

484

484

460

Suspended sediment

Mean 

percent

2.95

2.57

.73

.87

.54

.43

.49

.42

.41

.34

.32

.34

.36

.42

.74

.56

.57

.51

.43

.47

.40

.37

.41

.41

.39

.38

.31

.28

.28

.33

.30

Monthly load (tons) _ _

Tons per 

day

94,700

49,600

8,410

11,900

8,010

5,880

6,390

5,470

5, 340

3,670

3,690

4,020

4,750

6,880

15,500

10,200

9,920

8,250

6,660

7,520

6,120

5,560

5,880

6,010

5,850

5,070

4,150

3.750

3,670

4,320

3,720

330, 900

November

Mean 

discharge 

(secondfeet>

460

449

438

432

449

449

460

490

484

466

484

460

454

427

466

454

514

730

830

806

752

673

687

632

626

606

580

600

612

638

Suspended sediment

Mean 

percent

0.28

.36

.24

.21

.35

.46

.33

.27

.27

.22

.23

.26

.27

.33

.31

.52

.38

.77

.77

.84

.55

.55

.50

.46

.48

.48

.40

.39

.49

.56

Tons per 

day

3,480

4,370

2,830

2,450

4,230

5,580

4,100

3,560

3,530

2,780

2,990

3,240

3,320

3,800

3,880

6, 360

5,260

15,200

17, 200

18,300

11,200

9,980

9,280

7,850

8,090

7,850

6,260

6,310

8,090

9,630

201. 000

December

Mean 

discharge 

(secondfeet)

652

659

638

593

556

574

574

562

562

574

586

586

586

612

574

568

520

466

227

173

206

170

113

113

113

150

150

150

175

200

250

Suspended sediment

Mean 

percent

0.69

.52

.33

.33

.22

.26

.32

.32

.33

.38

.46

.43

.50

.52

.36

.28

.19

.24

.09

.06

.05

.06

.01

.18

.02

.17

.04

.10

.03

.05

.04

Tons per 

day

12,100

9,250

5,690

5,290

3,290

4,020

4,960

4,850

4,990

5,880

7,280

6,800

7,900

8,580

5,580

4,290

2,670

3,020

539

270

270

270

27

539

54

701

162

405

135

270

270

110, 400

1931

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- 

January

300

300

300

300

300

300

300

300

300

300

300

300

300

300

300

350

350

350

350

350

350

350

350

350

350

350

350

350

400

450

500

0.07

.05

.10

.08

.12

.08

.10

.12

.06

.04

.01

.01

.02

.05

.11

.07

.05

.03

.03

.03

.03

.05

.02

.03

.07

.04

.07

.12

.07

.09

.19

Monthly load (tons)..

566

405

809

647

971

647

809

971

485

324

81

81

162

405

890

647

485

270

270

270

270

485

189

270

647

378

647

1,130

755

1,080

2,560

18, 610

February

1,200

1,240

1,180

995

950

1,090

1,170

1,050

822

752

738

673

854

1,010

1,220

1,560

1,290

1,040

830

708

666

659

701

652

693

532

526

544

0.95

.58

.72

.78

.62

.81

.77

.74

.76

.72

.69

.53

.76

.79

1.10

2.83

1.93

1.39

1.06

.71

.56

.57

.47

.47

.35

.34

.39

.35

30, 700

19, 400

22, 900

20, 900

15, 900

23, 800

24,300

21,000

16,900

14, 600

13, 700

9,630

17,500

21,500

36, 200

119, 000

67, 200

39, 000

23,700

13,600

10,100

10,100

8,870

8,250

6,550

4,880

5,530

5,120

630, 800

March

526

520

490

466

416

427

478

508

508

466

405

416

438

478

544

580

580

568

612

680

768

745

708

659

760

1,220

968

934

708

738

694

0.27

.21

.24

.23

.34

.27

.39

.37

.26

.30

.37

.29

.39

.35

.40

.43

.45

.44

.44

.49

.71

.67

.56

.56

.55

1.88

.62

.61

.42

.36

.49

3,830

2,940

3,180

2,890

3,800

3,100

5,020

5, 070

3,560

3,780

4,050

3,260

4,610

4,500

5,880

6,720

7,040

6,740

7,250

8,980

14, 700

13,500

10, 700

9,950

11, 300

61, 900

16,200

15,400

8,010

7,170

9,170

274, 200
120 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. SO, 1941 Continued

1931

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

Mean 

discharge 

(secondfeet)

680

673

606

659

846

QKQ tfOtf

846

782

806

1,010

1,190

1,120

1,080

1,270

1,390

1,430

1,410

1,550

1,440

1,290

1,300

1,560

1,670

1,660

1,820

2,020

2,180

2,305

2,070

2,240

Suspended sediment

Mean 

percent

0.36

.38

.26

.43

.61

CQ * Off

.67

.48

.50

.82

.66

.58

.46

.60

.69

.59

.55

.79

.59

.36

.51

.62

.54

.58

.79

.84

.84

.79

.63

.73

Monthly load (tons).-

Tons per 

day

6,610

6,900

4,260

7,' 630

13,900

IE «jnfl JLO) OUU

15, 300

10,100

10, 900

22,300

21,200

17.500

13,400

20,600

25,900

22,800

20,900

33,000

22,900

12,500

17,900

26,100

24,300

26,000

38, 800

45,800

49,400

50,100

35,200

44,100

681,600

May

Mean 

discharge 

(secondfeet)

2,590

9 £1^ ^^OUU

2,530

2,830

3,140

3 j.ftft , *±Q\J 

3,080

2,770

2,890

3,280

3,150

2,770

2,350

2,180

2,290

2,830

4,030

4,820

4,740

5,400

5,000

4,100

3,280

2,710

2,710

3,410

4,520

5,000

4,240

3,340

3,220

Suspended sediment

Mean 

percent

1.06

1.22

.96

1.73

1.51

1.59

1.20

.96

1.01

1.24

.94

.80

.69

.58

.87

1,23

.90

1.30

1.25

1.40

1.09

.88

.56

.68

.78

1.00

.86

.64

.65

.54

.61

Tons per 

day

74,000

77,300

65,500

132, 000

128,000

149, 000

99,700

71,700

78,700

110,000

79,900

59,800

43,700

34,100

53,700

93,900

97,800

169,000

160, 000

204, 000

147,000

 97,300

49,500

49,700

57,000

92,000

105,000

86,300

74,300

48,700

53,000

2, 842, 000

June

Mean 

discharge 

(secondfeet)

3,890

4,590

u, 5 ldfin ±\J\J

4,820

5,640

5,560

4,460

4,590

5,240

5,560

4,440

3,890

3,220

3,340

3,410

3.220

3,220

3,150

3,020

2,590

2,240

1,960

1,850

1,630

1,500

1,490

1,480

1,360

1,360

1,900

Suspended sediment

Mean 

percent

0.84

.92

.92

.77

.86

84 !es

.69

.64

.74

.55

.51

.59

.70

.83

2.00

.48

.52

.41

.56

.38

.41 .46~

.28

.35

.29

.30

.66

.43

2.22

Tons per 

day

88,100

114,000

134,000

100,000

131, 000

126, 000

75,800

85,400

90,500

111,000

65,900

53,500

51,200

62,800

76,300

174,000

41,700

44,200

33,400

39,100

23,000

21,700

23,000

12,300

14,200

11,700

11,900

24,200

15,800

114, 000

1, 970. 000

1931

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....

July

2,070

3,020

3,610

4,740

3,340

3,410

2,350

1,740

1,430

1,140

918

775

619

526

460

380

258

309

380

176

213

460

314

186

143

104

99

83

1,020

870

910

1.24

1.01

.86

1.80

2.25

1.95

1.27

.85

.59

.43

.36

.28

.24

.20

.22

.16

.24

.33

1.50

.26

.26

.73

.77

.59

1.33

.83

.63

.38

.18

4.22

2.48

Monthly load (tons) . _

69,200

82, 300

83,700

230,000

203,000

179,000

80,500

39,900

22,800

13.200

8,900

5,850

4,020

2,830

2,720

1,650

1,670

2,750

15,400

1,240

1,480

9,060

6,530

2,970

5,120

2,320

1,670

863

4,960

99,000

60,900

1, 246, 000

August

2,550

3,480

3,150

1,170

680

432

1,930

1,290

1,160

1,050

1,060

1,120

822

632

508

454

680

562

606

318

632

490

514

270

176

153

135

128

111

95

108

11.5

9.64

7.89

4.97

3.39

2.30

3.65

3.53

3.62

2.73

1.92

2.13

1.35

.99

.84

.65

7.05

2.50

1.74

1.90

2.14

1.68

1.93

2.59

1.32

.95

.68

.44

.49

.33

.47

791, 000

905, 000

670,000

157, 000

62,200

26,800

190,000

123, 000

113, 000

77, 300

54,900

64,400

29, 900

16,900

11,500

7,960

129, 000

37,900

28,400

16,300

36,500

22, 200

26, 800

18,900

6,260

3,910

2,480

1,510

1,460

836

1,380

3. fi35. 000

September

148

113

176

117

82

62

95

133

88

161

89

66

82

124

1,560

2,180

918

1,820

3,450

2,120

1,850

3,340

2,240

3,960

2,530

2,410

2,890

2,180

2,020

1,690

1.55

1.57

1.99

1.36

.40

.26

1.26

1.33

.48

1.02

.53

3.21

2.36

1.35

3.65

5.12

3.99

2.46

6.57

5.15

3.60

5.53

2.70

4.87

3.21

2.92

2.10

1.34

1.27

.99

6,180

4,770

9,440

4,290

890

432

3,240

4,770

1,130

4,420

1,270

5,720

5,230

4,500

15,300

30,100

98,800

121,000

611, 000

294,000

180, 000

498,000

163,000

520,000

219,000

190,000

164,000

78,800

69,200

45,100

3, 354, 000
QUANTITIES OF SUSPENDED SEDIMENT 121

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended 

sediment in the San Juan River at gaging station near Bluff, Utah, Oct. 1, 1929, to 

Sept. SO. 1941 Continued

1931

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....

October

Mean 

discharge 

(secondfeet)

1,440

5,800

6,120

6,120

5,160

3,520

2,730

2,310

1,980

1,720

3,660

2,250

1,820

1,620

1,480

1,350

1,260

1,220

1,870

6,800

4,840

3,940

1,620

1,260

1,140

1,100

1,060

996

964

902

880

Suspended sediment

Mean 

percent

0.83

7.18

9.40

6.03

3.76

1.86

1.58

1.22

1.00

.92

2.86

3.10

1.98

1.34

1.02

.86

.84

.80

5.83

7.31

5.27

3.26

4.09

1.82

1.28

1.01

.91

.68

.60

.60

.59

Monthly load (tons).-.

Tons per 

day

32,200

1, 120, 000

1, 550, 000

995, 000

523,000

177,000

116,000

75,900

53,400

42,600

282,000

188,000

97,200

58,600

40,700

31,300

28,500

26,300

294,000

1, 340, 000

688,000

346.000 179; ooo

60,600

39,400

30,000

26,000

18,300

15,600

14,000

14,000

S, 502, 000

November

Mean 

discharge 

(secondfeet)

872

850

720

707

707

700

688

694

1,100

1,440

1.100

4,080

4,380

2,730

1,580

1,220

1,020

940

988

910

940

1,020

902

688

245

192

217

269

812

1,350

Suspended sediment

Mean 

percent

0.64

.75

.59

.47

.46

.57

.50

.53

.83

2.05

.98

3.91

3.17

2.97

1.87

1.40

1.03

.88

.77

.65

.67

.72

.47

.52

.17

.11

.14

.17

.32

.83

Tons per 

day

15,000

17,200

11,50ft

8,950

8,740

10,800

9,490

9,930

24,600

79,600

29,100

430,000

374,000

219,000

79,700

46,100

28,300

22,300

20,500

15,900

17,000

19,800

11,400

9,660

1,120

569

820

1,230

7,010

30,200

1, 206, 000

December

Mean 

discharge 

(secondfeet)

925

720

625

344

249

220

300

400

553

589

1,670

1,350

902

643

480

339

2G4

228

298

3bO

447

607

842

980

1,260

1,220

1,140

1,060

1,350

1,480

1,060

Suspended sediment

Mean 

percent

0.53

.28

.27

.23

.21

.23

.23

.19

.17

.28

.69

1.39

.35

.32

.35

.22

.09

.06

.16

.05

.09

.08

.07

.11

.11

.39

.22

.37

.88

.53

.59

Tons per 

day

13,200

5,450

4,560

2,130

1,400

1,380

1,860

2,050

2,540

4,450

31,100

50,600

8,520

5,560

4,530

2,020

701

378

1,290

512

1,080

1,320

1,590

2,910

3,750

12,800

6,770

10,600

32,000

21,100

16,900

255,100

1932

1 

2-.__

3 

4....

5 -

6 

7....

8 

9 

10 

11 

12_ 

13 

14-..

ld.___

16 

17 

18. 

19....

20. 

21. 

22--..

23 

24-..

25-...

26.-.

27.--.

28-..

29- 

30 

31_ 

IV

January

674

469

565

668

595

583

553

643

776

748

694

681

835

762

o83

' 524

. 571

458

513

513

480

535

571

607

625

625

553

452

294

145

425

[onthly loaf

0.18

.12

.26

.28

.22

.16

.2o

.25

.21

.39

.33

.43

.52

.40

.28

.30

.21

.14

.28

.36

.14

.14

.13

.12

.09

.16

.15

.13

.22

.09

.17

(tons)...

3,260

1,510

3,960

5,040

3,530

2,510

3,720

4,340

4,400

7,880

6,180

7,900

11,700

8,230

4,400'

4,230

3,240

1,730

3,880

4,990

1,810

2,020

2,000

1,970

1,510

2,700

2,240

1,590

1,750

351

1,940

116.500

February

508

649

858

1,220

1,220

850

1,060

10,500

15,700

11,900

8,220

5,480

3,520

3,060

2,550

2,490

2,250

2, 030

1,720

3,520

2,670

2,670

2,430

2,490

2,430

2,430

3,060

3,380

3,660

0.27

.31

.52

.42

.38

.32

.76

4.87

4.47

6.20

4.63

3.44

i.34

2.10

1.98

2.09

2.10

3.14

1.91

4.99

2.56

3.85

1.99

2.10

2.23

1.86

2.54

3.42

4.12

3,700

5,430

12,000

13,800

12,500

. 7, 330

21,700

1, 380, 000

1, 890, 000

1, 990, 000

1, 030, 000

508,000

222, COO

173,000

136, 000

140,000

127, OuO

172, 000

88,600

474,000

. 184,000

^77,000

130, 000

141,000

146,000

122,000

210,000

312,000

407,000

10,340.000

March

4,230

4,530

5,320

4,230

2,920

2,310

1,980

1,920

2,310

3,250

3,250

2,990

2,250

2,030

1,820

1,980

2,490

2,920

3,250

4,080

5,800

5,800

4,080

3,120

2,610

3,120

4,530

3,940

3,180

3,660

4,080

6.83

3.51

3.94

3.34

3.14

2.14

1.04

1.09

1.92

2.24

2.40

2.41

1.41

1.32

,93

1.58

1.06

1.22

1.90

2.78

3.80

3.70

2.92

1.60

1.34

1.25

5.54

2.10

1.28

1.26

1.64

779,000

429,000

565, 000

381,000

247,000

133,000

55,500

56,400

120,000

196,000

210,000

194,000

85,600

72,300

45,700

84,400

71,200

96,100

167,000

306,000

594,000

579, 000

321, 000

135, 000

94,300

105, 000

677, 000

223,000

110,000

124, 000

180,000

7, 436. 000
122 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of 

suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. 80, 1941 Continued

1932

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

Mean 

discharge 

(secondfeet)

5,160

4,530

6,460

8,220

8,590

8,970

8,970

7,680

6,630

7,320

6,970

7,140

8,220

9,350

10, 500

10, 100

10, 100

11,300

11,100

9,920

10, 100

9,730

8,780

8,220

6,630

5,480

5,480

5,480

5,160

5,000

klonthlv loa

Suspended sediment

Mean 

percent

1.32

1.20

2.96

3,53

4.02

3.56

3.74

5.49

3.40

4.25

4.42

3.94

1.63

3.70

3.82

1.91

1.89

1.79

1.78

1.89

1,50

1.46

1.34

1.25

1.09

.96

1.10

1.07

1.02

.62

d (tons')

Tons per 

day

184, 000

147, 000

516, 000

783, 000

931,000

861,000

905, 000

1,140,000

608, 000

839, 000

831, 000

759, 000

361,000

933, 000

1,080,000

520,000

515,000

546, 000

533, 000

506,000

409,000

383, 000

317,000

277, 000

195,000

142, 000

163,000

158, 000

142, 000

83, 600

15.770.000

May

Mean 

discharge 

(secondfeet)

4,680

4,680

5,000

6,120

7,320

8,220

8,400

7,500

6,460

6,630

7,500

8,040

8,780

10, 300

11,500

11,500

11,700

12,900

13, 700

15, 300

15, 300

14, 700

14, 100

16, 100

15, 300

14, 500

13, 300

10, 700

9,350

10, 700

12, 500

Suspended sediment

Mean 

percent

0.75

.93

.81

.82

.96

.88

.91

.76

.62

.52

.60

.67

1.34

.84

.78

1.00

.83

1.03

.94

1.18

1.26

1.06

1.14

1.23

1.09

1.02

1.08

1.04

.85

.78

.85

Tons per 

day

94, 700

117,000

109, 000

135, 000

190,000

195, 000

206,000

154, 000

108,000

93, 000

121,000

145, 000

317,000

233,000

242, 000

310, 000

262, 000

358, 000

347, 000

487, 000

520, 000

420, 000

433, 000

534, 000

450, 000

399, 000

387, 000

300, 000

214, 000

225,000

287, 000

8, 393, 000

June

Mean 

discharge 

(secondfeet)

11,700

9,350

9,350

9,730

9,350

8,040

7,140

5,960

5,480

6,120

7,140

7,860

8,220

9,540

11, 100

11,700

11,700

11, 700

10, 500

9,730

9,350

9,540

9,540

9,920

10, 900

10, 500

10, 500

9,730

8,780

7,860

Suspended sediment

Mean 

percent

0.85

.63

.62

.70

.60

.58

.52

.45

.42

.52

.67

.53

.54

.62

.60

.62

.71

.62

.62

.62

.54

.33

.55

.70

.76

.65

.56

.56

.56

.51

Tons per 

day

271,000

159, 000

156, 000

184,000

151,000

126, 000

100,000

72, 300

62, 100

85,800

129,000

112,000

120, 000

159, 000

180, 000

196,000

224, 000

196, 000

176,000

163,000

136,000

84,900

141, 000

187, 000

223, 000

184,000

159,000

147,000

133,000

108,000

4, 525, 000

1932

l-_ 

2-....

3...-.

4......

5......

6......

7......

8. 

9.. 

10..-

ll--._

12...-

13....

14...-

15....

16..-

17-.-

18. 

19....

20. 

21 .

22 

23.,..

24....

25....

26. 

27_ 

28. 

29 

30-.-

31....

July

7,500

7,140

7,140

6,460

6,120

6,120

5,480

4,840

4,230

3,940

3,940

3,940

4,680

5,320

5,160

4,530

3,940

3,660

3,520

3,060

3,250

2,800

2,370

2,140

1,980

1,980

2,080

1,920

1,870

4,230

3,520

Monthly los

0.59

.64

.79

,52

.43

.46

.35

.28

.42

.29

.33

.35

.46

.56

.49

.33

.43

.34

.41

1.30

1.03

.58

.46

.36

.30

.30

.44

.48

.36

2.67

2.82

d (tons) 

119,000

123,000

152, 000

90. 600

71, 000

75, 900

51, 700

36, 500

47, 900

30,800

35,100

37, 200

58, 100

80, 400

68,200

40, 300

45, 700

33,600

38, 900

107, 000

90, 300

43, 800

29,400

20,800

16, 000

16, 000

24, 700

24, 900

18,200

305, 000

268, 000

2,200,000

August

4,680

4,680

3,660

2,990

2,310

2,030

1,720

1,480

1,300

1,220

1,010

880

769

707

655

547

688

940

1,100

3,180

8,040

9,160

4,680

3,250

3,060

2,490

3,520

4,230

16, 500

10, 900

5,800

1.96

2.40

.95

.69

.53

.36

.30

.25

.18

.17

.14

.12

.18

.16

.13

.22

.89

1.83

1.52

3.00

8.25

11.3

4.26

2.77

1.95

1.55

2.00

2.84

12.4

4.12

1.76

247, 000

303, 000

93,800

55, 600

33, 000

19, 700

13,900

9,980

6,310

5.590

3,810

2,850

3,730

3,050

2,300

3,250

16, 500

46,400

45,100

257,000

1, 790, 000

2, 790, 000

538, 000

243, 000

161,000

104,000

190, 000

324, 000

5, 520, 000

1, 210, 000

275,000

14,320,000

September

4,230

3,380

2,860

2,490

2,080

1,870

1,620

1,350

1,300

1.220

1,060

996

932

850

805

776

734

707

668

619

553

541

910

3,380

4,840

2,310

2,250

1,400

1,180

948

1.22

.81

.73

.46

.48

.45

.48

.37

.40

.36

.28

.29

.28

.24

.22

.36

.28

.22

.29

.23

.19

.18

.22

3.91

6.05

4.00

3.22

2.57

1.47

1.16

139, 000

73, 800

56, 300

30,900

26,900

22, 700

21,000

13,500

14, 000

11,800

8,000

7,790

7,040

5,500

4,780

7,530

5,540

4,190

5,220

3,840

2,830

2,630

5,400

356, 000

790,000

249,000

195, 000

97,000

46,800

29,700

2, 244, 000

Estimated.
QUANTITIES OF SUSPENDED SEDIMENT 123

TABLE 18. Mean daily discharge, mean concentration, and daily load of 

'Suspended sediment in the San Juan River at.gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. SO, 1941 Continued

1932

Day

1

2

3

4

5

6_ 

7

8

9 -.

10. 

n.--

12. 

13--.-

14...-

15 

16. 

17 

18.-.-

19.--

20- 

21 

22. 

23. 

24..-.

25-..

26- 

27 ...

28.-.

29 

30 

31..-

October

Mean 

discharge 

(secondfeet)

798

762

720

694

734

668

661

625

776

741

727

. 741

805

776

755

734

694

688

681

649

681

727

1,620

1,100

1,060

1,010

932

910

828

776

805

Suspended sediment

Mean 

percent

0.73

.64

.51

.43

.51

.13

.18

.08

.58

.93

.65

.48

.48

.39

.36

.36

.31

.35

.32

.25

.28

.25

1.18

1.65

1.26

.74

.49

.48

.37

.34

.34

Monthly load (tons) 

Tons per 

day

15, 700

13,500

9,900

8,040

10,100

2,350

3,210

1,350

12,100

18,600

12,800

9,600

10,400

8,170

7,340

7,120

5,600

6,500

5,880

4,370

5,150

4,910

51,600

49,000

36,000

20,100

12,300

11,800

8.250

7,120

7,390

386, 100

November

Mean 

discharge 

(secondfeet)

769

727

720

727

734

700

687

700

681

649

681

694

643

631

601

577

571

589

583

571

583

595

613

601

601

583

595

£24

571

583

Suspended sediment

Mean 

percent

0.33

.32

.25

.25

.28

.28

.27

.24

.24

.25

.26

.22

.33

.24

.23

.23

.23

.22

.25

.22

.24

.26

.24

.20

.21

.23

.28

.30

.27

.27

Tons per 

day

6,850

6,280

4,850

4,910

5,560

5,290

4,960

4,530

4,400

4,370

4,770

4,130

5,720

4,070

3,720-

3,590

3,530

3,510

3,940

3,400

3,780

4,180

3,960

3. 240

3,400

3,610

4, 500

4,230

4,150

4,230

131, 700

December

Mean 

discharge 

(secondfeet)

631

613

607

625

674

655

565

630

541

535

520

501

480

460

450

440

430

420

411

422

431

342

268

280

300

330

278

206

134

26

310

Suspended sediment

Mean 

percent

0.35

.29

.31

.34

.30

.24

.27

.22

.27

.22

.28

.43

.14

.18

.09

.13

.09

.12

.24

.22

.15

.13

.15

.09

.06

.16

.11

.10

.10

.04

.24

Tons per 

day

5,960

4,800

5,070

5,720

5,450

4,230

4,130

3,160

3,940

3,180

3,940

5,800

1,810

2,240

1,080

1,540

1,050

1,350

2,670

2,510

1,750

1,190

1,080

674

485

1,430

836

566

351

27

2,000

80,000

1933

1

2 .-

34-~~~

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 

J

300

290

251

328

308

355

350

346

304

320

355

373

380

343

377

419

404

422

362

400

450

500

550

600

700

800

800

800

800

800

800

VIe$4hly loi

anuary

0.10

.10

.07

.02

.08

.07

.08

.06

.08

.08

.04

.05

.08

.08

.06

.11 .'04

.04

.04

.06

.07

.11

.20

.06

.07

.07

.07

.04

.02

.01

.08

<1 (tons).l

809

782

485

178

674

674

755

566

647

701

378 -512

809

728

620

1,240

432

458

378

647

863

1,483

2,970

971

1,320

1,510

1,510

863

432

216

1,726

26.300

800

750

700

700

700

700

650

600

600

600

600

650

700

700

750

800

800

800

800

850

850

850

900

900

1,000

1,500

1,980

2,030

Februar

0.04

.01

.09

.10

.04

.05

.06

.02

.02

.03

.02

.03

.04

.07

.06

.08

.05

.12

.10

.12

.17

.08

.18

.33

.56

.45

1.65

1.27

y

863

202

170

1,890

755

944

1,050

324

324

485

324

539

755

1,320

1,210

1,730

1,080

2,590

2,160

. 2,750

3,880

1,830

4,320

8,010

15, 100

18,200

88,100

69,500

osn. 'on

2,490

2,370

2,200

1,820

1,400

1,140

1,100

1,220

1,300

1,350

1,480

1,620

1,670

1,530

1,300

1,060

958

925

842

820

790

790

720

688

713

. 694

649

649

655

873

1,100

__'--

March

1.35

1.07

1.08

1.53

.76

.80

.64

.57

.54

.73

.83

.83

.73

.78

.70

.61

.51

.48

.44

.39

.36

.32

.26

.30

.33

.29

..25

.30

.27

.46

.42

-. --__

90,700

68,400

64,100

' 75, 100

28, 700

24,600

19,000

18,700

18,900

26,600

33, 100

36, 300

32,900

32,200

24,500

17,400

13, -200

12,000

9,980

8,630

7,660

6,820

5,040

5,560

6,340

5,420

4,370

5,260

4,770

10,800

12,500

729 600

72S606 47-
124 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18, Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. SO, 1941 Continued

1933

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 .

April

Mean 

discharge 

(secondfeet)

1.300

1.140

1.060

1,140

1,440

1,770

1,720

1,350

1,100

1,100

1,060

1,020

880

805

948

948

865

748

956

1,140

1,440

1,480

1,260

1.C60

980

820

783

783

842

842

Suspended sediment

Mean 

percent

0.82

.53

.43

.43

.47

.57

.57

.46

 Qi V7

.42

.41

.40

.27

.27

.33

.33

.26

.22

.40

.34

.61

.47

.35

.27

.28

.25

.24

.26

.35

.30

Monthly load (tons)..

Tons per 

day

28.800

16,300

12,200

13,200

18,300

27,200

9fi *'), Am\ *WU

16,700

11,000

12,600

11,700

11,000

6,420

5,860

8,440

8,440

6,070

4,450

10,300

10,500

23,700

18,800

11,900

7,710

.7,390

5,530

5,070

5,500

7,960

6,820-

366,200

May

Mean 

discharge 

(secondfeet)

1,260

1 1, dSft 4oU

1,440

j 400

1^530

1 480

1^530

1,580

1 480

1^400

1,480

1,350

1,220

1,220

1,140

1,100

980

776

865

1,920

3,660

5,640

6,460

5,640

4,230

3,520

3,380

4,530

6,290

7,140

8,400

Suspended sediment

Mean 

percent

0.43

.47

.43

54

!43

4Q 

. ^tf

 10Vf

 ^*49

.47

.48

.48

.46

.39

.38

.31

.31

.25

.21

.20

.72

1.15

1.06

1.26

1.0^

.68

.59

.80

.84 :ei

.90

1.12

Tons per 

day

14.600

18,800

16,700 «jO 4Qo

IJ, 700

19,600

20,200

17,9uu

10 QAfl lo, owu

18,100

19,100

16,400

12,800

12,500

9,520

9,200

6,610

4,400

4,67C

37,300

114, 000

161,000

220,000

155,000

66,200

56,000

72,900

103,000

164, 000

173,000

254,000

1, 844, 000

June

Mean 

discharge 

(secondfeet)

9,350

1ft Qfift lUj OUU

U, onn WJU

11,700

9,540

8,780

8,460

7 1, IrtU 14f1

6,800

4,840

6,800

8,970

9,540

8,970

8,220

7,320

6,970

7,140

7,320

6,970

7,320

7,3^0

7,3M

6,970

5,960

5,160

4,530

4,080

3,520

3,180

Suspended sediment

Mean 

percent

1.04

1.25

1.20

no

. If*

.92

.87

.80

.68

.70

.58

.68

.83

.90

.71

.59

.64

.53

.60

.66

.69

.76

.80

1.18

2.73

.98

.64

.55

.52

.47

.36

Tons per 

day

262,000

oj.7 nnn Ot* j UUU

385,000 xin *HU, find UUW

237,000

206,000

 181,000

131,000

109,000

75,700

125,000

261,000

232,000

172,000

131,000

126,000

99,600

116,000

130,000

130,000

150,000

158,000

233,000

513,000

158,009

89,100

67,200

57,200

44,600

30,900

5,187,000

1933

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....

2,920

2,490

2,140

2,030

2,140

2,550

-3, 620

5,000

3,800

4,530

3,800

3,060

2,920

3,250

2,140

1,720

1,530

1,720

1,770

1,260

1,060

85»

895

948

1,580

2,480

1,480

980

948

748

619

VI onthly lo

July

0.40

.29

.31

.30

.40

1.59

3.31

3.14

a. 98

2.41

2.68

1.30

1.46

1.44

1.62

1.30

1.07

3.03

1.77

2.32

1.38

.89

.63

.56

1.15

6.16

5.42

3.12

3.05

1.42

1.39

ad (tons)-

31,500

19, 500

17,flOO

16,400

23,100

109,000

314,000

423,000

305,000

294,000

264, UOO

107,000

115,000

126,000

93,5CO

60,300

44,100

141,000

84,500

78,800

39.500

20,600

15,200

14,300

49,000

414,000

216,000

82,500

78,000

28,600

23,200

3. 648. COO

631

655

565

524

441

674

1,820

3,180

2,610

1,530

1,060

842

643

577

452

430

357

261

245

231

308

375

257

166

231

172

163

157

160

182

166

August

2.04

1.67

1.29

1.13

1.03

1.22

6.71

6.98

6.97

5.47

3.93

2.17

1.44

1.07

.91

.65

.53

.49

.43

.29

.35

14.6

5.08

3.62

1.73

l.UO

1.21

.86

.68

.94

.68

34,700

29,500

19,700

16,000

12,200

22,200

329,000

599, OCO

491,000

226,000

112,000

49,300

25,000

16,600

11,100

7,550

5,100

3,450

2,830

1,810

2,910

148,000

35,200

15, 800

10,800

5,560

5,310

3,640

2,940

4,610

3,050

2, 252, 000

118

92

92

94

94

86

82

100

1,260

5,960

7,320

3,520

2,430

i.,730

- 3, 250

3,660

2,610

1,980

2,920

3,660

5,640

5,320

2,730

2,370

1,870

1,620

1,440

1,260

1,100

1,020

September

0.86

.98

.77

.50

.43

.31

.32

.49

.83

13.2

10.0

8.34

4.08

2.90

3.93

3.80

2,85

1.94

3.20

3.78

2.68

4.10

3.84

2.33

1.55

1.09

1,00

.87

.75

.55

2,720

2,430

1,910

1,270

1,080

728

701

1,320

28,200

2,120,000

1,990,000

792,000

267,000

214,000

344,000

375,000

201,000

104,000

252,000

373, uOO

408,000

588,000

283,000

149,000

78,200

47,600

^38,800

29,600

22,300

15,100

8,732,000
QUANTITIES OF SUSPENDED SEDIMENT 125

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. 30, 1941 Continued

1933

Day

1

2

3

4

5

6

7

8

9

18..-

11 

12 

13 

14 

15....

16....

17 

18 

19 

20 

21 

22....

23 

24 

25 

26 

27 

28. _

29 

30 

31 

October

Mean 

discharge 

(secondfeet)

972'

835

1,020

1,350

2,030

5,800

5,480

3,380

1,870

1,670

1,870

3,060

1,820

1,300

1,580

2,430

1,480

1,140

1,060

972

900

828

895

818

741

812

835

805

769

720

755

Suspended sediment

Mean 

percent

0.60

.63

.52

6.03

26.7

15.8

8.50

5.04

3.32

1.75

2.47

3.15

3.37

2.26

1.51

4.32

3.33

. 1.75

1.32

1.14

.81

.69

1.12

.74

.68

.68

.49

.51

.51

.50

.51

Monthly load (tons).

Tons per 

day

1,570

12,000

HSOO

220,000

1, 470, 000

2, 480, 000

1, 260, 000

460,000

168,000

78,900

125, 000

260,000

166,000

79,000

64,400

283,000

133,000

63,900

37,800

29,900

19,700

15,400

27,000

16,300

13,600

14,900

11,000

11,100

10,600

9,720

10,400

7,556,000

November

Mean 

discharge 

(secondfeet)

681

553

631

668

755

687

769

741

682

637

631

595

619

674

607

607

577

559

513

641

571

541

513

553

547

474

496

518

502

1,140

Suspended sediment

Mean 

percent

0.58

.42

-.61

.42

.54

.42

.57

.59

.40

.48

.41

.37

.44

.38

.38

.44

.44

.41

.44

.38

.41

.36

.35

.42

.27

.37

.46

.35

.32 JLOO

Tons per 

day

10, 700

6,260

10,400

7,590

11,000

7,800

11,800

11, 800

7,370

8,260

6,990

5,940

7,340

6,910

6,240

7,210

6,860

6,180

6,100

5,660

6,320

5,260

4,860

6,260

4,000

4,720

6,160

4,890

4,350

30,600

236,700

December

Mean 

discharge 

(secondfeet)

1,920

926

902

850

748

662

619

565

559

530

553

563

530

577

643

662

681

502

458

442

425

571

577

595

583

643

655

707

662

655

681

Suspended sedimentMean 

percent

2.48

1 28

L02

.83

.65

.60

.50

.43

4fi ^K>

.40

.43

.45

.52

.44

.47

.52

.53

.31

.30

.26

.20

.26

.36 '.60

1.50

.54

.63

.64

.51

.58

.55

Tons per 

day

129,000

32,000

24,800

19,100

13,100

10,700

8,370

6,560

6,940

6,720

6,430

6,720

7,450

6,860

8,150

9,290

9,760

4,210

3,700

3,100

2,300

4,000

5,620

8,050

7,880

9,370

11,200

12,200

9,130

10,300

10,100

412, 100

1934

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....

January

714

748

842

836

707

668

662

458

430

316

339

375

385

362

436

468

649

565

681

668

589

601

649

619

565

559

665

569

 571

608

480

0.46

.36

.43

.46

.37

.45

.37

.24

.25

.20

,21

..20

.15

.20

.19

.15

.46

.40

.52

1.05

.39

.49

.60

.56

.39

.44

.42

.35

.37

.31

.37

Monthlyload (tons) 

8,860

7,260

9,770

10,400

7,070

8,130

6,620

2,970

2,920

1,700'

1,920

2,020

1, 570

1,940

2,240

1,860

8,070

6,100

9,560

18,900

6,210

 7,940

10, 500

9,370

5,940

6,640

6,400

6,290

5,700

4,240

4,810

192,900

February

442

469

486

518

535

513

530

513

641

571

553

571

583

496

496

458

518

535

513

635

571

565

601

835

713

842

932

700

__._ __ ...

0.35

.28

.32

.35

.46

.39

.33

.40

.32

.37

.34

.34

.30

.30

.28

.26

.27

.33

.42

.33

.31

.25

.28

.69

.47

.55

.68

.42

----------

4,180

3,540

4,210

4,890

6,640

5,400

4,720

5,640

4,670

5,700

5,080

5,240

4,720

4,020

3,750

3,210

3,780

4,780

5,800

4,780

4,780

3,810

4,540

15,600

9,040

12,500

17, 100

7,940

170.000

March

613

619

619

565

513

535

530

452

577

619

613

637

607

601

637

762

805

769

948

925

762

707

741

828

880

812

842

820

783

727

694

._ _ _ ....

0.42

.41

.43

.36

.31

.33

.29

.23

.29

.34

.46

.40

.44

.52

.60

.48

.63

.72

.80

.92

.52

.48

.49

.49

.39

.49

.52

.42

.41

.39

.47

__ . ....

6,940

6,860

7,180

5,350

4,290

4,780

4,160

2,810

4,510

5,670

7,610

3,880

7,210

8,450

10,300

9,880

13,700

15,000

20,500

23,000

10,700

9,150

9,800

11,000

9,260

10,700

11,800

9,290

8,670

7,670

8,800

281,900
126 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended \sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. SO, 1941 Continued

1934

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

Mean 

discharge 

(secondfeet)

707

812

910

1,150

1,060

964

858

762

727

649

631

700

940

1,770

2,200

2,140

2,140

2,430

2,250

1,980

1,720

1,920

2,610

3,120

2,860

o nan o> uuu

3,520

3,660

3,380

3,250

Monthly loa

Suspended sediment

Mean 

percent

0.38

.33

.60

.50

.54

.51

.43

.43

.37

.35

.29

.64

.68

.88

1.26

.86

.92

1.07

.99

.89

.68

.77

.97

1.14

1.17

.89

1.18

1.01

.93

.91

d (tons)..

Tons per 

day

7,260

7,240

14,700

16, 500

15,400

13, 300

9,960

8,860

7,260

6,130

4,940

12, 100

14, 700

42,100

74,800

49, 700

53, 200

70,200

60,200

47,600

31,600

39, 900

68,400

96,000

90,300

7O KAA (O, OUU

112, 000

99,800

84,900

79, 900

1,311,000

May

Mean 

discharge 

(secondfeet)

3,190

2,990

3,660

3,250

2,610

2,200

1,920

2,080

3,120

3,250

3,380

4,230

3,940

3,800

3,660

3,250

2,610

2,550

2,490

2,370

2,200

1,720

1,630

1,480

1,300

1 140

l!o60

1,000

1,180

1,440

1,530

Suspended sediment

Mean 

percent

0.87

.86

1.15

1.00

.84

.89

.74

.96

1.40

1.02

.84

1.06

1.17

1.16

1.09

.83

.79

1.01

.93

.71

.93

.62

.47

.87

.53

.36

.43

.49

.40

.40

.54

Tons per 

day

74,900

69,400

114, 000

87,800

59, 200

52,900

38,400

53,900

118, 000

89,600

76, 700

120,000

124,000

119, 000

108,000

72, 800

56, 700

69,600

62,500

45,400

55,200

28,800

19, 400

34,800

18,600

11,100

12, 300

13, 200

12, 700

15,600

22,300

1,856,000

June

Mean 

discharge 

(secondfeet)

2,670

2,730

1,820

1,530

1,260

1,100

956

820

720

631

647

452

366

370

265

203

192

175

125

96

70

60

40

36

24

18

10

9

9

5

Suspended sediment

Mean 

percent

" 1.13

3.29

1.42

.73

.56

.40

.40

.31

.29

.31

.21

.20

.21

.13

.11

.11

.07

.05

.06

.04

.03

.04

.05

.01

.01

.01

.01

.01

.01

Tons per 

day

81,600

243,000

69,800

30,200

19,100

11,900

10,300

6,860

5,640

6,290

3,100

2,430

2,080

1,300

783

594

361

243

162

108

54

54

64

11

6

5

3

3

3

3

494,900

1934

1 __

3 

4 

5 

6 

7 

8 

9 

10 

11 

13 

14 

15_ 

16 

17 

18 .

19. 

20. 

21 

22. 

23-.-.

24. 

25 

26_ 

27 

28 .

29 .

SCSI 

July

1

1

0

0

0

0

0

0

0

0

0

0

0

2

30

20

10

8

4

704

1,050

769

353

1,220

518

273

745

1,000

880

385

224

0.03

.01

.01

.02

10.0

5.20

10.9

4.12

10.9

8.00

6.62

6.98

8.76

7.40

5.96

4.37

Monthly load (tons)..

3

3

3

3

35,600

147, 000

227,000

44,700

334,000

109, 000

48,800

157,000

237,000

176,000

62,000

26,400

1, 605, 000

August

154

138

108

95

100

55

45

45

147

203

183

95

80

65

502

339

175

118

120

151

265

135

65

125

55

192

1,030

4,920

2,370

1,770

3.75

3.62

2.87

2.05

1.96

1.02

.66

1.48

.72

3.38

4.46>

3.90

4.53

4.83

9.95

5.78

4.16

4.66

5.10

3.94

3.65

4.80

5.22

3.75

4.54

2.86

3.74

8.69

20.3

16.0

8.38

15,600

13,500

8,370

5,260

5,290

1,500

810

1,810

10, 500

18,500

22,000

9,990

9,770

8,480

85,000

72,100

39,800

25,100

16,300

12,800

14,900

34, 300

19,000

6,590

15,300

4,240

19,400

242,000

2, 700, 000

1,020,000

400,000

4,858,000

September

910

714

607

508

316

189

112

699

547

375

321

224

281

547

491

366

169

151

140

105

90

85

90

500

1,980

3,120

1,720

1,180

980

940

5.17

4.09

3.42

2.86

2.-7S

1.89

1.41

4.28

6.32

2.75

5.49

4.73

3.58

4.60

3.38

4.10

4.97

3.66

2.70

1.63

1.24

1.12

.84

.74

7.43

7.82

3.09

1.98

1.44

.96

127,000

78,800

56,100

39,200

23,700

9,640

4,270

80,800

78,600

27,800

47; 600

28,600

27,200

67,900

44,800

40,500

22,700

14,900

10,200

4,620

3,020

2,560

2,050

55,100

367, 000

659,000

144,000

63, 100

38,100

24,400

2, 193, 000
QUANTITIES OF SUSPENDED SEDIMENT 127

TABLE 18. Mean daily discharge, mean .daily concentration, and daily load of 

suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. SO, 1941 Continued

1934

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....

October

Mean 

discharge 

(secondfeet)

850

720

619

547

474

425

420

OQC OoO

344

334

290

269

245

257

217

228

308

326

281

294

344

334

326

334

298

277

273

269

249

238

192

Suspended sediment

Mean 

percent

a. si

.74

.61

.56

.45

.42

.41

.38

. 

9QA?

.30

.27

.27

.22

.21

.27

.21

.20

.20

.18

.18

.20

.20

.19

.17

.15

.13

.14

.16

.17

.17

.13

Monthly load (tons) . .

Tons per

day

18, 360

14,390

10,200

8,260

5,750

4,810

A fiAf] *±j \f±\J

3 940

2 7Afl t /uu 

2,700

2,110

1', 970

1,460

1,460

1,590

1,300

1,670

1,760

1,380

1,430

1,860

1,810

1,670

1,540

1,220

972

1,030

1,160

1,130

1,080

675

106,000

November

Mean 

discharge 

(secondfeet)

160

125

135

166

285

203

qnQ oUo

OftC £i DO

onq OUO

316

290

334

285

321

303

312

366

469

410

464

486

458

508

442

474

415

415

474

385

464

Suspended sediment

Mean 

percent

0.14

.15

.13

.15

.10

.15

.24

1 Q 

. J-O

* 1Q±y 

.19

.21

.31

.21

.22

.25

.23

.22

.78

.34

.44

.50

.34

.44

.36

.39

.33

.31

.37

.30

.33

Tons per 

day

594

513

486

675

756

810

2 000

1J300

1,570

1,620

1,650

2,810

1,620

1,920

2,050

1,940

2,190

9,880

3,750

5, 510

6,560

4,210

6,050

4,290

5,000

3,700

3,480

4,720

3,130

4,130

88,910

December

Mean 

discharge 

(secondfeet)

316

290

115

100

TOE J-iU

175

1 Fkfl J.OU

200

ocn £i\J\J

316

339

312

375

762

964

1,060

828

707

655

565

547

425

405

464

447

458

464

442

380

420

513

Suspended sediment

Mean 

percent

0 34

!24

.16

.10

.08

.38

.10

.11

, .20

.24

.16

.16

.44

1.72

.78

.75

.81

.55

.42

.40

.38

.28

.29

.39

.43

.38

.32

.28

.27

.31

.34

Tons per 

day

2,890

1,890

486

270

270

1,7,80

405

594

1,350

2,050

1,460

1,350

4,460

35,400

20,300

21,500

18,100

10, 500

7,420

6,100

5,620

3,210

3,160

4,890

5,180

4,700

4,000

3,350

2,780

3,510

4,700

183, 700

1935

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 

January

513

464

410

348

344

425

366

513

583

571

565

1,400

1,140

1,000

1,300

1,020

1,100

776

613

273

100

100

150

200

300

300

700

932

1,820

918

988

0.39

.35

.34

.24

.32

.44

.22

.50

.57

.66

.47

3.22

1.56

1.00

2.36

1.65

2.07

1.07

.91

.52

.14

.01

.00

.02

.03

.04

.10

.92

.95

.74

1.46

Monthly load (tons) . _

5,400

4,370

3,750

2,270

2,970

5,050

2,190

6,910

8,960

10,200

7,180

122,000

48,000

27,000

82,800

45,400

61, 500

22,400

15,100

3,830

378

27

11

108

243

324

1,890

23,200

46,700

18,300

38,900

617,400

February

948

1,060

1,060

1,000

910

888

910

1,020

1,140

1,060

980

902

835

925

880

842

755

655

553

508

571

734

1,020

1,260

1,220

918

872

714

1.27

1.41

1.54

1.50

1.28

1.02

.84

.68

1.11

.78

.74

.54

.50

.70

.48

.47

.40

.34

.44

.52

.59

1.04

1.25

1.66

2.13

1.64

1.16

.86

32,500

40,400

44, 100

40,500

31,500

24,500

20, 600

18. 700

34. 200

22, 300

19, 600

13, 100

11,300

17, 500

11,400

10, 700

8,150

6,020

6,560

7,130

9,100

20,600

34,400

56,500

70,200

40,600

27, 300

16,600

696, 100

March

619

547

681

996

1,220

1,300

1,020

835

700

741

748

625

688

755

835

1,480

1,870

1,620

1,400

1,260

1,180

1,260

1,260

1,400

1,440

1,480

1,820

1,820

2,200

2,310

2,370

0.57

.51

.73

1.40

1.14

L12

.85

.71

.60

.56

.55

.43

.47

.63

.76

2.93

1.87

2.25

1.67

1.09

.98

1.05

1.36

1.43

1.87

1.39

1.65

1.27

1.65

1.65

1.51

9,530

7,530

13,400

37, 600

37, 600

39,300

23> 400

16,000

11,300

11,200

11,100

7,260

8,720

12,900

17, 100

117,000

94,400

98,400

63,100

37, 100

31,200

35, 700

46,300

54,100

72,700

55, 500

81,100

62,400

98,000

103, 000

96,600

1, 411, 000
128 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended 

sediment in the San Juan River at gaging station near Bluff, Utah, Oct. 1, 1989, 

to Sept. SO, 1941 Continued

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

Mean 

discharge 

(secondfeet)

3,120

3,520

3,380

3,660

4,230

4,080

3,660

3,380

3,180

4,680

4,380

2,800

2,490

2,670

3,380

4,530

5,480

5,960

5,800

6,120

5,800

5,480

5,320

5,320

5,000

.5,160

3,940

3,520

3,800

4,080

Suspended sediment

Mean 

percent

1.76

2.32

1.96

1.83

1.92

1.86

1.46

1:06

1.12

1.49

2.38

1.45

1.21

1.23

1.29

1.48

1.68

1.34

1.83

1.44

1.68

1.64

1.42

1.41

1.32

1.39

.96

.96

1.05

1.35

Monthly load (tons)..

Tons per 

day

148, 000

220,000

179,000

181,000

219,000

205,000

144,000

96,700

96,200

188,DOO

281,000

110,000

81,400

88,700

118,000

181,000

249,000

216,000

287,000

238,000

263,000

243,000

204,000

203,000

178, 000

194,000

102,000

91,200

108,000

149,000

5,262,000

May

Mean 

discharge 

(secondfeet)

4,080

4,230

4,230

3,660

3,660

3,120

3,120

3,060

3,060

3,380

3,940

4,530

5,320

6,120

7,500

6,970

6,460

5,960

. 6,460

6,120

7,140

11,300

8,590

7,140

6,970

7,680

8,590

9,160

9,160

8,970

8,590

Suspended sediment

Mean 

percent

1.56

1.00

1.02

.91

.98

.94

1.03

.83

.68

.84

.86

.97

1.34

1.32

1.47

1.13

1.78

1.83

1.81

1.93

1.25

2.51

1.99

1.06

1.16

1.14

1.17

1.35

1.08

1.07

1.09

Tons per 

day

172, 000

114,000

116,000

89,900

96,800

79,200

86,800

68,600

56,200

76,700

91,500

119,000

192,000

218,000

298,000

213,000

310,000

295,000

316,000

319,000

241,000

766,000

462,000

204,000

218,000

236,000

271,000

334,000

267,000

259,000

253,000

6,839,000

June

Mean 

discharge 

(secondfeet)

8,780

, 7,860

6,800

6,970

8,780

10,100

11,500

13,300

14,100

14,900

15,500

16,500

17,100

16,100

15, 700

17,300

18,500

15,500

12,300

12,500

13,700

14,900

14,900

13,300

12,700

12,700

11,100

10,500

10,100

9,360

Suspended sediment

Mean 

percent

1.01

1.12

.82

.80

.94

.99

1.06

1.19

1.12

1.12

1.27

1.11

1.17

1.00

1.04

1.01

1.03

.90

.81

.86

.76

.96

1.04

1.03

.70

.68

.72

.73

.81

.69

 - .. ..--

Tons per 

day

239,000

238,000

151,000

151,000

223,000

270,000

329,000

427,000

426,000

451,000

531,000

494,000

540,000

435,000

441,000

472,000

514,000

377,000

269,000

290,000

281,000

386,000

418,000

370,000

240,000

233.000

216,000

207,000

221,000

174,000

10,010,000

1935

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 

July

8,590

8,400

7,860

7,320

7,140

6,800

6,290

5,960

5,960

5,800

5,640

5,640

5,000

4,840

4,680

4,530

4,380

3,660

5,800

3,940

4,230

4,080

3,660

3,660

3,120

2,550

2,250

1,980

1,820

2,080

2,730

0.87

.76

.65

.70

.70

.41

.72

.52

.69

.63

.54

.48

.46

.38

.53

.63

.78

.54

2.71

1.17

.83

.77

.66

.54

1.00

.52

.28

1.06

1.28

1.38

1.77

Monthly load (tons)--

202,000

172, 000

138,000

138,000

135.000

75,300

122, 000

83,700

111,000

98,700

82,200

73,100

62,100

49,600

67,000

77, 100

92,200

53,400

424, 000

124,000

94,800

84,800

65,200

53,400

84,200

35,800

17, 010

56, 700

62,900

77,500

19,800

3,211,000

August

2,610

2,080

2,370

1,980

2,140

2,610

2,670

2,310

2,800

3,520

2,550

2,080

1,670

1,770

1,720

1,670

2,250

1,440

1,440

1,530

1,220

964

880

1,220

2,140

2,920

2,920

2,200

2,550

2,030

1 870

_ __ ....

4.45

1.84

1.90

2.95

2.48

3.25

3.40

3.21

4.13

3.68

1.47

3.25

2.13

1.39

1.70

1.09

1.91

2.09

1.11

.80

.55

.43

.36

.51

2.63

4.41

3.26

2.90

2.25

1.28

1.61

314,000

103,000

122,000

158,000

143,000

229,000

245,000

200,000

312,000

350,000

101,000

182,000

96,000

66,400

78,900

49,100

116,000

81,300

43,100

33,000

18,100

11,200

8,560

16,800

152, 000

348,000

257,000

172,000

155, 000

70, 100

81, 300

4, 313, 000

September

2,730

2,550

1,770

1,720

1,400

1,100

1,060

1,670

1,440

1,480

1,620

1,260

1,060

918

842

727

681

694

619

530

474

486

452

559

3,940

6,460

3,520

9,920

12,500

3,800

2.08

4.72

4.67

3.01

1.47

1.08

1.10

1.79

2.08

2.05

1.34

.96

.95

.79

.57

.44

.35

.31

.30

.27

.28

.25

.38

3.91

5.95

8.84

6.33

8.42

8.72

5.27

___ ... __ ... ......

153,000

325,000

223,000

140,000

55,600

32,100

31,500

80,700

80,900

81,900

58,600

32,400

27,200

19,600

13,000

8,640

6,430

5,800

5,020

3,860

3,590

3,290

4,640

59,000

633,000

1, 540, 000

602,000

2, 260, 000

2, 940, 000

541,000

9, 971, 000
QUANTITIES OF SUSPENDED SEDIMENT 129

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended 

. sediment in the San Juan River at gaging station near Bluff, Utah, Oct. 1, 1929, 

to Sept. 30, 1941 Continued

1935

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....

October

Mean 

discharge 

(secondfeet)

2,310

1,870

1,670

1,530

1,400

1,300

1,260

1,260

1,100

1,060

980

895

895

872

828

812

776

748

720

734

1,260

1,620

1,260

1,100

932

980

. 940

910

850

850

842

Suspended sediment

Mean 

percent

2.98

1.05

1.57

.75

. .54

.44

.38

.40

.41

.36

.38

.37

.30

.29

.27

.22

.24

.29

.26

.25

.19

1.90

3.01

1.43

.99

.94

.69

.55

.43

.51

.40

Monthly load (tons)..

Tons per 

day

185,900

53,000

70,800

31,000

20,410

15,440

12,930

13, 610

12,180

10, 310

10,040

8,940

7,240

6,830

6.050

4,830

5,020

5,860

5,050

4,970

22,100

83,100

102,400

42,500

24,920

24,870

17,520

13,500

9,880

11,720

9,100

852,000

November

Mean 

discharge 

(secondfeet)

842

835

762

727

748

748

720

688

655

643

688

707

707

714

643

649

637

625

619

655

655

674

637

601

649

694

707

734

727

674

Suspended sediment

Mean 

percent

0.43

.34

.32

.33

.32

.29

.29

.24

.24

.26

.24

.25

.26

.25

.26

.26

.22

.22

.31

.23

.21

.23

.23

.26

.21

.31

.29

.27

.28

.24

Tons per 

day

9,770

7,670

6,590

6,480

6,450

5,860

5,640

4,460

4,240

4,510

4,460

4,780

4,970

4,810

4,510

4,560

3,780

3,730

5,180

4,080

3,730

4,180

3,940

4.210

3.670

5,800

5,540

5,350

5,510

4,370

152,800

December

Mean 

discharge 

(secondfeet)

613

601

565

601

625

643

688

694

668

655

625

595

547

502

496

496

490

420

405

312

321

321

348

513

518

518

474

370

420

535

535

Suspended sediment

Mean 

percent

0.24

.23

.34

.36

.29

.26

.26

.25

.24

.24

.20

.21

.20

.19

.22

.23

.19

.15

.12

.12

.12

.13

.14

.22

.20

.32

.19

.19

.29

.23

.19

Tons per 

day

3,970

3,730

5,180

5,830

4,890

4,510

4,830

4,700

4,320

4,240

3,380

3,380

2,940

2,560

2,940

3,080

2,540

1,701

1,323

999

1,053

1,134

1,323

3,050

2,810

4,480

2,430

1,890

3,290

3,320

2,750

98,57

1936

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 ...

January

559

425

447

474

420

370

518

577

619

595

571

595

601

589

649

694

681

783

631

442

405

452

491

458

565

637

748

880

842

820

762

0.23

.21

.18

.23

.13

.17

.29

.15

.06

.15

.18

.23

.38

.18

.29

.26

.23

.24

.24

.18

.16

.19

.11

.14

.19

.25

.25

.32

.27

.24

.31

Monthly load (tons)..

3,480

2,403

2,160

2,940

1,480

1,701

4,050

2,349

999

2,403

2,780

3,700

6,160

2,860

5,080

4,860

4,240

5,080

4,080

2,160

1,760

2,320

1,458

1,728

2,890

4,290

5,050

7,610

6,130

5,320

6,370

109,800

February

727

727

918

727

688

607

513

436

452

541

625

631

681

783

956

1,220

1/180

1,060

1,180

1,060

902

812

741

798

1,000

1,820

1,670

1,020

805

0.29

.27

.39

.31

.30

.24

.13

.13

.14

.21

.19

.20

.25

.35

.45

.86

.77

.66

.81

.66

.59

.54

.52

.48

1.42

2.20

2.29

1.39

1.23

5,700

5,290

9,670

6,080

5,560

3,940

1,809

1,539

1,701

3,080

3,210

3,400

4,590

7,400

11, 610

28,300

24,540

18,900

25,800

18,900

14,360

11,830

10,390

10,340

38,300

108, 100

103, 200

38, 300

26,700

552, 500

March

734

865

1,530

3,120

3,660

3,800

3,380

2,990

2,920

3,120

3,250

3,120

2,430

2,200

2,430

2,670

2,670

2,370

2,140

1,920

2,030

1,820

1,870

2,200

1,920

1,480

1,440

1,260

1,180

1,260

1,530

0.79

.69

1.34

2.17

3.07

3.00

3.25

2.40

1.95

1.82

1.76

1.68

1.53

1.18

1.16

1.23

1.11

1.13

1.00

1.14

.79

.74

.92

1.12

.64

.54

.64

.44

.48

.51

.56

15,660

16,120

55,400

18,280

303,000

308,000

297,000

193, 800

153, 700

153,300

154,400

141,500

100,400

70,100

76,100

88,700

80,000

72,300

57,800

59,100

43,300

36,400

46,400

66,500

33,200

21, 570

24,890

14,960

15,280

17,360

23,140

2,758,000
130 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended 

sediment in the San Juan River at gaging station near Bluff, Utah, Oct. lt 1929, 

to Sept. 30, 1941 Continued

1936

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

Mean 

discharge 

(secondfeet)

1,820

2,490

1,980

1,670

2,080

1,770

1,530

1,530

1,580

3,060

3,940

4,230

5,160

6,800

7 680

7,680

7,140

7,680

8,040

7,680

7,500

7,500

7,680

8,220

8,040

7,140

7,140

6,970

6,800

6,630

Suspended sediment

Mean 

percent

0.86

1.17

.86

.84

.90

.75

.63

.64

.82

, 1.22

1.48

.99

1.26

1.74

1 62

1.50

1.41

1.27

1.32

1.18

1.18

.93

.96

1.14

1.03

.83

1.00

.96

.92

.80

Monthly load (tons) - .

Tons per 

day

42, 300

78,600

46,000

37, 900

50. 500

35, 900

26,000

26, 400

35, 000

100, 800

157, 500

113, 100

175, 600

319, 000

336,000

311, 000

272, 000

263, 000

287, 000

244, 700

239, 000

188, 300

199, 000

253,000

223, 600

160, 000

192, 800

180,700

168, 900

143, 200

4, 907, 000

May

Mean 

discharge 

(secondfeet)

6,460

5,480

5,320

6,970

8,590

9,920

11,500

10, 300

7,680

6,120

4,840

4,230

4,080

5,160

6,120

6,120

6, 460

6,800

7,500

7,140

7,500

7,680

7,320

6,800

6,970

6,970

7,500

7,140

6,630

6,120

6,630

Suspended sediment

Mean 

pprcent

0.84

.64

.67

.80

.88

1.23

1.21

1.33

.98

.65

.47

.48

.54

.53

60

.50

.55

.63

.64

.80

.81

.88

.75

.55

.63

.64

.84

.69

.57

.55

.58

Tons per 

day

146, 500

94, 700

96, 200

150, 600

204, 100

329, 000

376, 000

370, 000

203, 200

107, 400

61,400

54, 800

59, 500

73, 800

99,100

82, 600

95,900

115, 700

129, 600

154, 200

164, 000

182, 500

148, 200

101, 000

118, 600

120, 400

170, 100

133, 000

102, 000

90,900

103, 800

4, 439, 000

June

Mean 

discharge 

(second - 

feet)

7,320

7,140

6,120

5,000

3,940

3,380

2,920

2,990

3,380

3,940

4,230

4,230

4.080

4,080

3,800

3,520

3,120

2,920

2,730

2,490

2,250

1,980

1,720

1,480

1,440

1,400

1,350

1,220

1,180

1,000

Suspended sediment

Mean 

percent

0.80

.74

.61

.49

.45

.29

.22

.35

.37

.29

.35

.35

.32

.34

; .29

.24

.24

.25

.24

.23

.21

.21

.16

.17

.16

.17

.19

.14

.13

.19

Tons per 

day

158, 100

142, 700

100, 800

66,100

47,900

26,500

17, 330

28,200

33,800

30,900

40,000

40,000

' 35, 300

37,400

29,800

22, 820

20, 220

19, 710

17,680

15,4Sft

12, 740

11, 230

7,420

6,800

6,210

6,430

6,910

4,620

4,130

5,130

1, 002, 000

1936

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. 

July

872

828

902

769

631

571

508

469

405

400

430

980

474

1,920

1,350

980

918

688

674

583

553

707

607

502

469

480

415

344

357

395

410

0.18

.12

.11

.08

.11

.13

.10

.06

.09

.07

.13

1.11

1.25

1.16

.50

.27

.33

.23

.26

.39

.23

.30

.60

.28

.21

.19

.28

.21

1.33

.70

.63

Monthly load (tons) . _

4,240

2,670

2,670

1,674

1,863

1,998

1,377

756

972

756

1,512

29, 400

15, 980

60,100

18, 220

7,155

8,180

4; 270

4,720

6,130

3,430

5,720

9,830

3,810

2,650

2,457

3,130

1,940

12, 820

7,450

6,970

234, 800

August

326

850

607

915

3,950

7,140

6,460

6,800

4,530

3,250

2,550

1,920

1,670

1,530

1,350

1,220

1,100

1,400

1,140

888

2,380

4,530

3,180

1,720

1,180

888

727

625

667

5,440

7,500

0.24

4.96

2.56

2.25

21.4

8.81

6.42

4.48

3.26

1.79

1.14

.83

.74

.62

.71

.43

.45

2.01

1.65

1.51

3.75

5.03

5.69

3.55

2.54

1.52

.96

.65

.54

6.56

7.50

-.----._._-__--- _ __-

2,106

13,800

42,000

55, 600

2, 282, 000

1, 698, 000

1, 120, 000

823, 000

399, 000

157, 100

78, 500

43, 000

33, 400

25, 600

25,900

14, 180

13, 360

76, 000

50,800

36, 200

241, 000

615, 000

489,000

164,900

80,900

36, 400

18, 850

10,960

9,720

964, 000

1, 519, 000

11,240,000

September

6,970

6,800

5,480

5,160

3,380

3,520

2,730

2,250

1,980

1,720

1,720

1,620

1,820

1.720

1,440

1,220

1,100

1,020

1,010

1,260

1,400

1,620

2,670

2,030

1,670

1,260

1,060

1,100

1,400

1,140

6.17

5.72

6,27

5.31

3.34

1.95

1.27'

.96

.77

.68

.73

.77

.93

1.54

.84

.57

.52

.42

.44

.80

1.19

8.12

3.73

3.79

2.79

1.73

1.09

1.00

1.58

1.98

 - _-_ --

1, 161, 000

1, 050, 000

928,000

740,000

305,000

185,300

93,600

58, 300

41,200

31,600

33,900

33,700

45,700

71, 500

32, 700

18, 760

15,440

11,560

11, 990

27,200

45,000

355,000

269, 000

207, 700

125, 800

58,900

31, 200

29, 700

59, 700

60,900

6, 139, 000
QUANTITIES OF SUSPENDED SEDIMENT 131

TABLE 18. Mean daily discharge, mean concentration, and daily load of-suspended 

sediment in the San Juan River at gaging station near Bluff, Utah, Oct. 1, 1929, 

Ito Sept: 30, 1941 Continued

1936

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--

October

Mean 

discharge 

(secondfeet)

1,060

996

964

988

948

902

858

1,020

1,060

980

888

842

769

727

681

714

694

649

681

1,080

1,870

1,670

1,260

1,260

1,060

940

895

872

865

1,180

. 4, 120

Suspended sediment

Mean 

percent

1.38

1.01

.82.

.76

.66

.56

.51

.57

.65

.76

.54

.52

.52

.46

.38

.35

.35

.33

.38

.86

2.01

2.78

1.49

1.43

.82

.65

.55

.58

.67

1.15

9.00

Monthly load (tons) _

Tons per 

day

39,500

27,200

21,300

20,300

16,900

13,600

11,800

15,700

18,600

20, 100

12,900

11, 800

10,800

9,030

6,990

6,750

6,560

5,780

6,990

24,600

101,000

125, 000

50,700

48,600

23, 500

16,500

13,300

13,700

15, 600

36,600

1,000,000

1, 752, 000

November

Mean 

discharge 

(secondfeet)

2,490

2,430

1,980

2,030

1,400

1,140

1,060

1,140

1,180

1,140

1,060

1,020

1,060

1,020

1,020

1,020

1.060

1,020

1,060

1,100

1,140

1,100

1,060

980

972

948

932

872

888

910

Suspended sediment

Mean 

percent

4.21

2.95

2.23

2.04

1.19

1.03

.83

.87

.84

.76

.72

.64

.67

.57

.71

.60

.51

.53

.50

.63

.68

.57

.55

.74

.55

.44

.47

.55

.49

.42

-- __ . __ ___-_ _ .

Tons per 

day

283,000

194,000

119,000

112, 000

45,000

31,700

23,800

26,800

26, 800

23,400

20,600

17,600

19, 200

15,700

19,600

16,500

14,600

14, 600

14, 300

18, 700

20,900

16, 900

15,700

19,600

14,400

11,300

11,800

12,900

11,700

10,300

1, 202, 000

December

Mean 

discharge 

(secondfeet)

902

872

842

« 842

805

714

734

734

649

613

577

577

565

491

452

631

1,010

902

980

902

828

798

842

798

812

940

972

940

872

783

850

Suspended sediment

Mean 

percent

0.39

.42

.48

.31

.32

.30

.43

.43

.35

.31

.19

.23

.22

.16

.21

.28

.61

.38

.40

.39

.36

.34

.36

.34

.35

.65

.56

.38

.40

.41

.40

Tons per 

day

9,500

9,890

10,900

7,050

6,960

5,780

8,520

8,520

6,130

5,130

2,960

3,580

3,360

2,120

2,560

4,770

16,600

9,250

10,600

9,500

8,050

7,330

8,180

7,330

7,670

16, 500

14, 700

9,640

9,420

8,670

9,180

250, 400

1937

l-_ 

2. 

3 

4--...

5-. 

6 ._

7- 

8__-_.

9-.._

If)-...

11 

12....

13.-..

14. 

15 

16..-.

17-...

18. 

19-..

20. 

21 .

22 

23 -

24_ 

25-..

26--.

27. 

28....

29. 

30. 

31.-..

January

688

625

234

140

400

400

400

400

«0

400

4$Q400

400

400

400

400

400

400

400

400

400

' 400

400

400

400

400

400

400

400

400

400

0.26

.29

.19

.15

.39

.06

.09

.03

.03

.04

.10

.09

.04

.03

.02

.05

.06

.09

.07

.05

.06

.08

.08

.04

.04

.04

.08

.09

.06

.08

.09

Monthly load (tons) _ .

4,830

4,890

1,200

567

4,210

648

972

324

324

432

1,080

972

432

324

216

540

648

972

756

540

648

864

864

432

432

432

864

972

648

864

972

32, 870

February

1,000

1,000

1,000

1,500

2,000

3,380

4,080

5,160

2,310

1,350

1,600

2,550

1,580

2,200

7,200

5,130

7,140

3,940

3,250

2,430

1,620

1,140

1,100

1,220

1,400

1,580

1,720

1,260

x

0.06

.07

.04

.10

.07

.11

.11

4.43

2.31

.94

.42

.50

.42

.46

2.94

1.69

2.79

3.47

2.71

2.13

1.78

1.46

1.12

1.02

1.31

3.21

1.75

1.77

1,620

1,890

1,080

4,050

3,780

10,000

12,100

617, 000

144, 000

34,300

18, 100

34, 400

17, 900

27,300

572, 000

234, 000

538, 000

369, 000

238,000

140, 000

77,900

44,900

33, 300

33,600

49,500

137, 000

81, 300

60,200

3, 536, 000

March

1,060

1,000

1,140

1,350

1,480

1,260

1,180

1,260

1,720

2,490

3,060

3,520

3,800

4,080

5,480

4,530

5,000

6,120

7,680

4,840

3,380

2,670

3,180

4,840

3,940

2,920

2,730

2,490

3,120

3,060

2,920

1.30

.94

1.02

1.59

1.75

1.86

1.47

1.39

1.79

2.45

2.37

3.20

3.82

3.21

4.15

3.11

3.02

3.69

4.04

2.83

1.76

1.44

1.45

2.82

2.62

2.09

1.28

1.02

1.13

1.25

2.01

37,200

25,400

31,400

58,000

69,900

63,300

46,800

47,300

83, 100

165, 000

196,000

304,000

392,000

354,000

614, 000

380,000

408,000

610,000

838,000

370,000

161, 000

104,000

124, 000

369, 000

279,000

165, 000

94,300

68,600

95,200

103, 000

158,000

6, 814, 000
132 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the San Juan River at gaging station near Bluff, Utith, 

Oct. 1, 1929, to Sept. 30, 1941 Continued

1937

Day

1 ..

2

3

4

5

6

7

8

9

10 

11- 

12.-..

13....

14....

IS....

16 

17 

18-..

19,.-

20--.

21- 

22-..

23 -.

24....

25 

26 .

27- __

28.. 

29....

30.._.

31

April

Mean 

discharge 

(secondfeet)

2.550

3,660

5,480

6,120

5.000

4,080

4,380

4,230

4,530

5,800

7,320

9,160

10,900

11,900

12,700

14, 300

16,500

15, 300

12,900

11,700

11,500

11, 300

12,500

12,500

9,920

8,220

8,780

10,500

8,590

8,220

Suspended sediment

Mean 

percent

1.10

2.01

2.35

2.65

2.18

1.46

1.80

1.71

1.71

1.55

2.32

2.66

2.49

2.69

2.31

2.49

2.43

2.35

1.94

1.90

1.75

1.72

1.94

2.00

1.44

1.10

1.07

1.27

1.49

1.21

Monthly load (tons) _ .

Tons per 

day

75, 700

199, 000

348, 000

438, 000

288, 000

161, 000

213, 000

195, 000

209, 000

243, 000

459, 000

658, 000

733, 000

864, 000

792, 000

961, 000

1, 080, 000

971, 000

676, 000

600, 000

543, 000

525, 000

655, 000

675, 000

386, 000

244, 000

2,54, 000

360, 000

346, 000

269,000

14,420,000

May

Mean 

discharge 

(secondfeet)

6,800

5,800

6,120

7.860

9,730

11,500

11,500

10, 300

10, 500

12, 500

13, 100

13, 100

12, 900

13, 300

14,300

14,900

14,900

14,900

14,900

14,100

12, 100

11, 700

11.300

11, 700

11, 300

9,730

8,220

6,800

6,970

7.860

9,160

._ _ _. __ _

Suspended sediment

Mean 

percent

0.87

.72

.69

.89

1.06

1.28

1.02

.91

.94

.98

1.08

1.02

1.08

1.12

.99

.95

.88

.94

.95

.93

.84

.80

.76

.77

.82

.69

.58

.60

.54

.82

.79

. _ .. _ _

Tons per 

day

160, 000

113,000

114.000

189, 000

278, 000

397, 000

317, 000

253, 000

266, 000

331, 000

382, 000

361, 000

376, 000

402, 000

382, 000

382, 000

354, 000

378, 000

382, 000

354, 000

274, 000

253, 000

232, 000

243. 000

250, 000

181, 000

129, 000

110, 000

102, 000

174, 000

195, 000

8, 314, 000

June

Mean 

discharge 

(secondfeet)

8,970

7,860

6,800

 7,140

6,800

6.460

5,800

5,160

5,000

5,160

5,1W)

4,680

5,480

5,960

5,640

5,480

4,840

4,840

5,480

5,800

5 480

5,160

5,160

5,160

4,840

4,840

4,230

5,000

4, 840

3,940

. ____ __ _

Suspended sediment

Mean 

percent

0.96

.78

.49

.51

.52

.63

.63

.50

.56

.45

.62

.54

.44

.37

.40

.39

.35

.40

.42

.38

.36

.34

.61

.45

. .41

 .33

. .38

.67

1.54

.59

... _ _-_ _

Tons per 

day

233,000

166. 000

90.000

98,300

95,500

110,000

98.700

69, 700

75,600

62,700

86,400

68,200

65, 100

59,500

60,900

57,700

45, 700

52,300

62,100

59,500

53,300

47,400

85, 000

62,700

53,600

43,100

43,400

90,400

144,000

62,800

2.403,000

1937

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. ...

 July

3,660

3,660

3,380

3,380

3,060

2,490

2,490

2,310

2,140

3,660

4,530

8,970

6,460

3,520

2.860

2,430

2,080

1,920

1,670

1,350

1,140

940

828

688

535

595

790

1,830

2,480

3,250

3,380

0.43

.69

.49

.54

.44

.33

1.60

.39

.60

5.92

8.40

7.86

7.64

3.18

1.67

.86

.78

.64

.66

.47

.39

.33

.32

.30

.21

.24

.37

2.42

4.44

7.90

8.93

Monthly kad (tons)..

42, 500

68, 200

44, 700

49, 300

36, 400

22,200

108, 000

24,300

34, 700

585, 000

1, 030, 000

1, 900, 000

1, 330, 000

302, 000

129, 000

56, 400

43, 800

33, 200

29,800

17, 100

12,000

8,380

7, 150

5,570

3,030

3.860

7,890

120, 000

297, 000

693, 000

815, 000

7. 859. 000

August

2,250

1,220

1,260

902

812

1,100

1,400

940

762

714

571

480

410

348

303

269

196

217

281

496

425

334

298

265

220

178

160

130

210

776

1,440

4.07

2.20

1.57

1.16

.77

1.97

2.40

2.45

1.60

1.15

.84

.56

.46

.37

.31

.40

.32

1.54

.77

.97

.77

.78

.69

.43

.42

.32

.28

.33

3.22

4.10

3.88

247,000

72,500

53, 400

28,300

16, 900

44,600

90,700

62,200

32, 900

22,200

13. 000

7,260

5,090

3,480

2,540

2,910

1,690

9,020

5,840

13, 000

8,840

7,030

5,550

3,080

2,490

1,540

1,210

1,160

18, 300

85, 900

151, 000

1. 021. 000

September

1,480

1,720

1,220

790

655

486

783

790

535

688

607

390

312

308

285

249

245

206

189

157

154

157

189

178

140

138

169

206

245

10,200

5.14

8.48

X 14.2

4.82

5.37

2.84

2.17

6.78

3.33

2.66

2.38

2.46

1.88

1.32

.90

.67

.64

.46

.41

.40

.35

.39

.34

.32

.40

.39

.40

.47

.84

13.3

205,000

394,000

468,000

103, 000

95,000

37,306

45,800

145, 000

48,100

1 49, 400

39,000

25,900

15, 80b

1 11, 000

6,930

4,500

4,230

2,560

2,090

1,700

1,460

1,650

1,740

1,540

1,510

1,450

1,830

2,610

5,560

2, 840, 000

4, 564, 000
QUANTITIES OF SUSPENDED SEDIMENT 133

TABLE 18. Mean daily discharge, mean daily concentration, and daily load of 

suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. SO, 1941 Continued

1937

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....

:

October

Mean 

discharge 

(secondfeet)

14,000

4,560

2,260

1,350

1,040

910

850

805

734

727

674

637

589

595

. 631

929

1,500

1,390

1,350

1,030

880

850

798

776

762

741

755

762

762

714

694

Suspended sediment

Mean 

percent

14.20

7.95

4.68

3.09

2.06

1.21

.91

.72

.55

.52

.38

.40

.28

.27

.27

.39

1.56

2.00

2.28

1.62

1.28

.93

.74

.55

.48

.44

.36

.36

.36

.33

.32

Monthly load (tons)-.

Tons per

day

5,370,000

979,000

286,000

113, 000

57,800

29,700

20,900

15,600

10,900

10,200

6,920

6,880

4,450

4,340

4,600

9,780

63,200

75,100

83,100

45,100

30,400

21,300

15,900

11,500

9,880

8,800

7,340

7,410

7,410

6,360

6,000

7,338,000

November

Mean 

discharge 

(secondfeet)

700

707

674

655

649

649

637

649

649

655

776

700

649

- 668

649

619

589

601

571

565

589

559

559

630

530

547

518

530

524

502

Suspended sediment

Mean 

percent

0.35

.33

.32

.27

.25

.25

.24

.28

.32

.33

.52

.37

.30

.31

.27

.28

.25

.22

.22

.23

.26

.23

.27

.21

.25

.21

.21

.20

.25

.19

Tons per 

day

6,620

6,300

5,820

4,770

4,380

4,380

4,130

4,910

5,610

5,840

10,900

6,990

5,260

5,590

4,730

4,680

3,980

3,570

3,390

3,510

4,130

3,470

4,080

3,010

3,580

3,100

2,940

2,860

3,540

2,580

138,600

December

Mean 

discharge 

(secondfeet)

460

450

465

508

565

625

Ul 577*

637

607

619

619

637

681

707

769

720

714

694

643

613

565

595

513

465

475

553

583

589

607

649

607

Suspended sediment

Mean 

percent

0.18

.16

.17

.26

.35

.39

.26

.32

.22

.27

.29

.19

.31

.40

.42

.31

.33

.31

.27

.30

.29

.38

.19

.17

.14

.20

.21

.17

.28

.23

.26

Tons per 

day

2,240

1,940

2,130

3,570

5,340

6,580

4,050

5,500

3,610

4,510

4,850

3,270

5,700

7,640

8,720

6,030

6,360

5,810

4,690

4,970

4,420

6,100

2,630

2,130

1,800

2,990

3,310

2,700

4,590

4,030

4,260

136,500

1938

1-- 

2. _ .

3.. 

4__ 

5.. 

6. .

7-. 

8.. 

9.._-

}0....

11...-

12-...

13....

14....

15....

16....

17..-

18..__

19-...

20....

21....

22....

23....

24....

25..-

26-.-

27....

28....

29....

30-.-.

31...-

January

571

530

595

783

700

700

688

625

583

460

440

450

475

513

530

559

613

688

835

850

762

714

649

553

518

425

323

384

683

607

649

0.17

.17

.17

.62

.30

.40

.29

.29

.20

.18

.10

.20

.28

.27

.22

.28

.29

.29

.58

.48

.43

.29

.27

.19

.17

.15

.11

.17

.48

.39

.48

Monthlyload (tons) 

2,620

2,430

2,730

13,100

5,670

7,560

5,390

4,890

3,150

2,240

1,190

2,430

3,590

3,740

3,150

4,230

4,800

5,390

13,100

11,000

8,850

5,590

4,730

2,840

2,380

1,720

969

1,760

7,560

6,390

8,410

163,600

February

643

835

720

681

681

700

625

565

502

530

787

1,500

1,890

1,740

1,790

1,170

948

835

756

68b

631

637

681

681

631

607

607

727

0.46

.40

.65

.48

.33

.35

.31

.18

.18

.23

.20

1.65

2.51

1.65

2.27

1.66

1.06

.81

.73

.63

.44

.55

.48

.38

.35

.33

.38

.32

7,990

9,020

12,600

8,830

6,070

6,620

5,230

2,750

2,440

3,290

4,250

66,800

128,000

77,500

110,000

52,400

27,100

18,300

14,900

9,850

7,500

9,460

8,830

6,990

5,960

5,410

6,230

6,280

t

630,600

March

3,250

5,340

6,010

9,020

8,620

4,270

2,480

1,740

2,200

1,640

1,500

1,460

1,640

2,3/0

3,080

2,540

1,640

1,550

1,740

1,690

1,600

1,890

2,540-

1,990

1,740

2,590

3,610

3,740

3,740

3,870

3,370

4.43

5.64

5.18

6.67

5.39

2.89

1.78

1.22

1.95

1.01

.85

.82

1.14

1.43

1.80

1.75

1.18

1.20

1.20

1.02

1.12

1.07

1.27

1.22

1.00

1.27

1.87

1.71

1.31

1.42

1.26

389,000

813,000

841,000

1,620,000

1,250,000

333,000

119,000

57,300

116,000

44,700

34,400

32,300

50,500

91,500

150,000

120,000

52,300

50,200

56,40ft

46,500

48,400

54,600

87,100

65,600

47,000

88,800

182,000

173,000

132,000

148,000

115,000

7,409,000
134 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended 

sediment in the San Juan River at gaging station near Bluff, Utah, Oct. 1, 1929, 

to Sept. SO, 1941 Continued

1938

Day

1

2

3

4

5

6

7

8

9

10....

11-..

12....

13..-

14....

15....

16....

17..-.

18....

19....

20__-

21....

22....

23....

24....

25..-.

26-...

27-...

28...-

29..-

30-...

31

April

Mean 

discharge 

(secondfeet)

2,810

2,200

1,990

1,790

2,040

3,250

3,490

3,310

2,860

2,540

2,540

3,550

4,710

5,840

6,190

5,670

4,270

4,410

5,840

8,820

10,500

10,500

11,800

12,200

12,900

13 100

13,300

10, 700

8,820

10,500

Suspended sediment

Mean 

percent

1.23

1.23

83

.88

.86

1.27

1.51

1.39

.93

.79

.78

.98

1.24

1.66

1.69

1.54

.91

.91

1.70

2.20

1.98

1.80

1.83

1.60

1.67

1.61

1.51

1.49

1.09

1.39

Monthly load (tons) ...

Tons per 

day

93,000

73,100

44,600

42, 500

47,400

111, 000

142, 000

124,000

71,800

54,200

53, 500

93,900

158,000

262, 000

282, 000

236,000

105,000

108, 000

268,000

524,000

561, 000

510, 000

583,000

527, 000

582,000

569,000

542,000

430, 000

260,000

394,000

7, 852, 000

May

Mean 

discharge 

(secondfeet)

11,600

12,900

10, 300

7,480

6,370

5,330

4,710

4,410

4,060

3,680

3,550

3,250

3,250

3,680

4,860

8,620

11,800

11,600

9,840

8,240

7,290

6,190

6,010

6,370

6,190

7,480

9,020

11, 100

13,100

15, 600

17,000

Suspended sediment

Mean 

percent

1.31

1.26

1.34

1.05

1.12

.65

.66

KA . Ut

.55

.51

.55

.45

.50.

.69

.71

.95

1.06

1.10

1.04

.79

.75

.73

.71

.76

.70

.78

.84

.95

.88

1.00

1.13

Tons per 

day

410,000

439, 000

373, 000

212,000

193, 000

93,500

83,900

64,300

60,300

50,700

52,700

39,500

43,900

68,600

93,200

221, 000

338,000

345, 000

27«,000

176,000

148,000

122,000

115,000

131,000

117, 000

158, 000

205,000

285, 000

311, 000

421, 000

519, 000

6, 166, 000

June

Mean 

discharge 

(secondfeet)

15,800

15,400

15,100

14,000

15,400

15,800

14,700

13,300

11,100

9,630

9,020

9,020

8,620

9,840

12,900

10, 000

9,220

9,220

9,420

9,420

8,430

9,630

13,300

14,900

12,200

9,840

9,220

10,000

10,500

9,420

Suspended sediment

Mean 

percent

1.10

.89

.92

.69

.77

.89

.85

.81

.74

.66

.62

.63

.57

.68

.70

.75

.61

.59

.68

.73

.68

.87

.87

1.21

1.22

.85

.66

.74

1.19

.69

Tons per 

day

469, 000

370,000

375, 000

261,000

320,000

380,000

337, 000

291, 000

222,000

172,000

151, 000

153,000

133,000

181, 000

244, 000

202,000

152,000

147,000

173, 000

186, 000

155,000

226,000

312,000

487,000

402, 000

226,000

164, 000

200,000

337, 000

175,000

7, 603, 000

1938

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..-

July

16,500

12,500

9,020

7,670

6,910

6.010

5,170

4,560

4,000

3,490

3,140

2,8fiO

2,700

2,420

2,320

2.540

2,760

2,260

2,100

1,990

1,990

2,200

1,690

1,640

1,460

1,360

1,200

1,140

1,120

980

1,240

1.15

.91

.68

.64

.45

.47

.27

.35

.28

.27

.27

.23

.25

.21

.28

.25

.36

1.05

.51

.35

.34

- .47

1.44

.38

.27

.27

.22

.22

.34

.36

.29

Monthlyload (tons)___

512, 000

307. 000

166,000

133,000

84,000

76,300

37,700

43,100

30,200

25, 400

22, 900

17,800

18,200

13, 700

17,500

17, 100

26,800

64, 100

28, 900

18, 800

18,300

27, 900

65, 700

16,800

10,600

9,910

7,130

6,770

10,300

9,530

9,710

1, 853, 000

August

1,180

1,020

895

820

734

734

681

981

1,190

755

1,360

700

895

1,740

1,490

2,590

1,420

948

700

613

496

445

416

389

346

288

232

220

204

210

198

0.22

.18

.15

.15

.11

.13

.14

.15

2.03

1.07

1.13

2.93

12.1

2.22

4.08

6.01

3.96

2.29

1.30

.82

.57

.46

.31

.28

.20

.17

.16

.12

.09

.09

.08

7,010

4,960

3,620

3,320

2,180

2,580

2,570

3,970

65,200

21,800

41,500

55,400

292, 000

104,000

164, 000

420,000

152,000

58,600

24,600

13, 600

7,630

5,530

3,480

2,940

1,870

1,320

1,000

713

496

510

428

1,469,000

September

1,250

3,080

7,480

8,820

7,650

3,870

3,490

3,870

4,630

2,480

3,280

4,270

6,370

6,010

4,860

3,870

4,630

3,080

2,700

2,320

2,040

1,840

1,600

1,420

1,260

1,160

1,110

1,040

964

872

1.94

4.46

8.69

11.0

7.89

4.27

2.71

2.97

5.48

3.98

2.13

4.08

4.60

2.49

1.42

.99

2.13

2.00

1.74

1.10

.77

.61

.48

.60

.36

.33

.28

.24

.25

.23

65,500

371, 000

1, 760, 000

2, 620, 000

1, 630, 000

446,000

255, 000

310,000

685, 000

267,000

189, 000

470, 000

791, 000

404,000

186, 000

103,000

266, 000

166,000

127, 000

68,900

42,400

30, 300

20,700

23,000

12,200

10,300

8,390

6,740

6,510

5,420

11, 350, 000
QUANTITIES OF SUSPENDED SEDIMENT 135

daily discharge, mean concentration, and daily load of susthe

TABLE 18. Mean

pended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. 30, 1941 Continued

1938

Day

1

2

3

4

5

6

7

8

9

10....

11-...

12..--

13. 

14.. 

15....

16....

17....

18.-..

19 

20 

21....

22....

23 

24 

25.-..

26 

27 

28. 

29 

30..-.

31.,..

October

Mean 

discharge 

(secondfeet)

888

858

828

790

727

755

783

925

4,410

4,270

2,860

2,420

2,150

1,990

1,890

1,840

1,990

2,040

2,040

2,260

2,100

1,940

1,790

1,690

1,600

1,550

1,460

1,420

1,320

1,260

1,270

Suspended sediment

Mean 

percent

0.25

.22

.20

.20

.21

.26

.22

.21

3.19

2.39

1.42

.88

.71

.61

.48

.46

.59

.50

.50

.61

.53

.48

.47

.44

.39

.39

.34

.36

.33

.30

.30

Monthly load (tons)..

Tons per 

day

5,990

5,100

4,470

4,270

4,120

5,300

4,650

5,240

380,000

276,000

110,000

57,500

41,200

32, 800

24,500

22, 800

31,700

27,500

27,500

37,200

30,100

25,100

20,700

20, 100

16,800

16, 300

13,400

13,800

11,800

10,200

10, 300

1, 296, 000

November

Mean 

discharge 

(secondfeet)

1,250

1,330

1,420

1,370

1,340

1,250

1,170

1,180

1,080

996

940

1,030

1,040

1,000

980

902

895

925

918

910

880

888

895

835

649

595

577

607

593

589

Suspended sediment

Mean 

percent

0.32

.32

.36

.34

.34

.29

.36

.28

.28

.21

.21

.24

.30

.28

.26

.20

.24

.22

.25

.24

.24

.22

.30

.24

.19

.13

.17

.21

.21

.17

Tons per 

day

10,800

11,500

13,800

12,600

12,300

9,790

11,400

8,920

8,160

5,650

5,330

7,400

8,420

7,560

6,880

2,930

5,800

5,490

6,200

5,900

5,700

5,280

7,250

5,410

3,330

2,090

2,650

3,440

3,360

2,700

208,000

December

Mean 

discharge 

(secondfeet)

790

918

880

835

850

835

783

776

776

776

741

734

727

714

720

727

748

762

828

812

1,050

910

888

865

783

649

565

571

595

607

649

Suspended sediment

Mean 

percent

0.22

.44

.38

.30

.30

.22

.24

.23

.24

.29

.28

.35

.30

.28

.29

.35

.35

.33

.35

.28

.74

.32

.32

.33

.26

.22

.22

.26

.19

.21

.22

Tons per 

day

4,690

10,900

9,030

6,760

6,880

4,960

5,070

4,820

5,030

6,080

5,600

6,940

5,890

5,400

5,640

6,870

7,070

6,790

7,820

6,140

21,000

7,860

7,670

7,710

5,500

3,860

3,360

4,010

3,050

3,440

3,860

199, 700

1939

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 

January

619

619

637

720

748

727

700

727

769

7sJO

769

707

714

662

607

625

571

513

631

571

674

798

996

858

805

700

674

668

734

700

662

0.20

.20

.31

.36

.27

.24

.20

.37

.28

.29

.21

.24

.30

.25

.25

.38

.27

.13

.21

.24

.30

.43

.54

.29

.30

.28

.23

.25

.50

.40

.28

Monthly load (tops)..

3,340

3,340

5,330

7,000

5,450

4,710

3,780

7,260

5,810

6,190

4,360

4,580

5,780

4,470

4,100

6,410

4,160

1,800

3,580

3,700

5,460

9,260

14, 500

6,720

6,520

5,290

4,180

4,510

9,910

7,560

5,010

174,100

February

643

571

524

235

259

435

421

583

700

619

407

565

518

631

655

755

850

741

828

776

714

707

674

643

637

694

714

727

0.18

.25

.19

.10

 .11

.19

.13

.16

.43

.21

.16

.17

.13

.27

.18

.38

.46

.27

.22

.25

.30

.33

.22

.21

.25

.31

.21

.27

... _ 

3,120

3,850

2,690

634

770

2,230

1,480

2,520

8,130

3,510

1,760

2,590

1,820

4,600

3,180

7,750

10,600

5,400

4,920

5,240

5,780

6,300

4,000

3,640

4,300

5,810

4,050

5,300

116,000

"~ March

637

649

668

674

688

707

637

625

727

1,010

1,600

1,600

1,890

1,840

1,990

2,200

2,150

2,100

2,200

2,320

2,590

3,140

4,130

5,670

5,670

4,710

4,130

4,060

4,270

3,490

2,930

0.28

.18

.31

.27

.31

.31

.29

.20

.53

.54

.93

1.06

1.42

1.50

1.74

2.03

2.23

2.08

1.88

1.67

2.19

1.86

1.81

2,25

2.45

1.61

1.07

1.04

1.06

.75

.66

____ . 

4,820

3,150

5,590

4,910

5,760

5,920

4,990

3,380

10,400

14,700

40,200

45,800

72,500

74,500

93,500

121,000

130,000

118,000

112,000

105,000

153,000

158,000

202,000

344,000

375, 000

205,000

119,000

114,000

122,000

70,700

52,200

2,891,000
136 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended 

sediment in the San Juan River at gaging station near Bluff, Utah, Oct. 1, 1929, 

to Sept. SO, 1941 Continued

1939

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

Mean 

discharge 

(secondfeet)

2,700

2,540

2,860

3,490

4,000

5,170

4,270

3,940

3,370

3,370

3,740

3,490

3,080

2,920

2,980

2,920

2,760

2,540

2,260

1,990

1,990

2,260

2,810

3,610

4,270

3,740

3,250

3, 030

3,080

3,800

Monthly lo£

Suspended sediment

Mean 

percent

0.59

.67

.75

.75

.82

2.31

1.59

1.09

.88

.75

.97

1.10

.85

.86

.75

.88

.85

.70

.33

.39

.30

.38

.50

.66

.70

.52

.57

.54

.64

.78

id (tons) 

Tons per 

day

43,000

45,900

57,900

70,700

88,600

322, 000

183,000

116/000

80,100

68,200

98,000

104,000

70, 700

67,800

60,300

69, 400

63,300

48,000

20,100

21,000

19, 300

23,200

37,900

64,300

80,700

52,500

50,000

44,200

53,200

80,000

2, 203, 000

May

Mean 

discharge 

(secondfeet)

5,010

5,010

5,010

5,840

5,010

5,010

6,010

6,370

5,010

4,860

5,500

6,550

6,730

6,010

5,330

4,710

4,560

4,270

3,610

3,430

4,410

6,010

6,190

6,190

6,010

4,860

4,000

3,550

3,870

4,410

4,710

Suspended sediment

Mean 

percent

0.61

.81

.82

.92

.76

.79

.94

1.01 .70-

.67

.68

1.00

.84

.75

.67

.59

.61

.71

.61

.77

.72

.97

.87

.79

.82

.50

.44

.48

.83

.74

.69

Tons per 

day

82,500

110,000

111,000

145,000

103,000

107, 000

152, 000

174, 000

94,700

87,900

101, 000

177, 000

153,000

122,000

96,400

75,000

75, 100

81,900

59,500

71,300

85, 700

157, 000

145, 000

132, 000

133, 000

65,600

47,500

46,000

86,700

88,100

87,700

3, 253, 000

June

Mean 

discharge 

(secondfeet)

5,010

4,860

4,710

4,130

4,410

5,010

5,500

4,560

3,800

3,490

3,430

3,370

3,200

2,860

2,700

2,700

2.480

2,200

2,040

1,790

1,550

1,260

1,050

812

707

694

637

655

625

589

Suspended sediment

Mean 

percent

0.61

.61

.62

.51

.59

.61

.68

.55 '.38

.41

.29

.36

.34

.29

.31

.33

.30

.33

.28

.19

.20

.19

.15

.12

.11

.13

.07

.07

.08

.08

Tons per

day

82,500

80,000

78,800

56,900

70,300

82,500

101,000

67,700

39,000

38,600

26,900

32,800

29,400

22,400

22,600

24,100

20,100

19,600

15,400

9,180

8,370

6,460

4,250

2,630

2,100

2,435

1,204

1,237

1,350

1,272

951, 000

1939

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. 

July

583

565

585

553

535 5'18

421

412

376

371

288

259

281

252

207

168

137

115

127

124

86

95

76

56

38

25

13

46

631

246

144

0.12

.07

.06

.07

.08

.11

.08

.08

.06

.05

.04

.04

.03

.05

.01

.01

.02

.02

.02

.01

.01

.01

.01

.01

.01

.01

.01

.01

.99

3.50

3.51

Monthly load (tons)..

1,890

1,070

948

1,040

1,160

1,540

910

891

610

502

310

281

227

340

57

46

73

62

68

32

23

26

20

15

10

7

4

12

16,900

23,200

13,600

65,870

August

266

204

292

223

159

134

109

84

99

97

68

68

69

69

46

34

24

14

11

7

3

1

1

0

0

0

0

1

0

140

270

2.10

3.23

3.78

.89

2.64

.45

.35

.21

.21

.30

.12

.06

.04

.09

.07

.04

.02

.01

.00

.01

.01

.01

.00

.00

.00

.00

.00

.76

.00

8.00

5.83

15,100

17,800

29,800

5,360

11,300

1,630

1,030

475

562

786

221

111

76

167

86

38

13

4

0

1

0

0

0

0

0

0

0

21

0

30,200

42,500

157,300

September

281

342

249

189

259

715

435

465

812

1,090

4,060

11,000

7,100

3,800

3,430

3,430

3,310

2,420

1,990

1,840

1,690

1,330

1,240

1,040

980

1,510

2,800

1,140

1,080

1,180

2.57

3.39

7.96

1.60

2.48

6.75

1.57

4.22

3.86

2.43

5.07

20.9

5.57

3.18

2.65

1.27

1.41

1.46

.80

.68

.81

.87

.52

.89

.89

2.76

2.69

1.87

1.35

.83

19,500

31,300

53,500

8,160

17, 300

130,000

18,400

53,000

84,600

71,500

556,000

6, 210, 000

1, 068, 000

326,000

245,000

118; 000

126,000

95,400

43,000

33,800

37,000

31,200

17,400

25,000

23,600

112,000

203,000

57,600

39,400

26,400

9, 881, 000
QUANTITIES OF SUSPENDED SEDIMENT 137

TABLE 18. Mean daily discharge,* mean concentration, and daily load of suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. 30, 1941 Continued

1939

Day

1

2

34'

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..-.

i October

Mean 

discharge 

(sejcondffeet)

974

878

854

776

724

681

.628

602

691

643

607

643

W4

628

582

563

539

, 475

475

458

441

453

445

424

408

420

404

484

1,550

776

. 659

Suspended sediment

Mean 

percent

0.76

.49

.36

.30

.31

.20

.20

.14

.26

.43

.48

.51

.46

1.02

.46

.48

.27

.25

.24

.24

.15

.15

.22

.14

.16

.15

.27

.20

.54

.40

.34

Monthly load (tons) 

Tons per 

day

20,000

11,600

8,300

6,290

6,060

3,680

3,390

2,280

4,850

7,470

7,870

8,850

8,120

17,300

7,230

7,300

3,930

3,210

3,080

2,970

1,790

1.840

2,640

1,600

1,760

1,700

. 2, 950

2,610

22,600

8,380

6,050

197, 700

November

Mean 

discharge 

(secondfeet)

578

568

612

602

578

558

568

582

649

800

854

794

713

708

638

654

638

628

582

597

587

573

568

558

553

520

553

549

530

563

Suspended sediment

Mean 

percent

0.36

.32

.28

.25

.25

.24

..25

.25

.31

.45

.36

.39

 .49

.34

.29

.34

.33

.32

.40

.31

.24

.23

.33

.32

.25

.22

.33

.25

.25

.29

Tons per 

day

5,620

4,910

4,630

4,060

3,900

3,620

3,830

3,930

5,430

9,720

8,300

8,360

9,430

6,500

5,000

5,860

5,680

5,430

6,290

5,000

3,800

3,560

5,060

4,820

3, 730

3,090

4,930

3,710

3,580

4,410

156,200

December

Mean 

discharge 

(secondfeet)

582

587

534

544

558

516

511

511

563

549

539

516

488

506

506

488

475

441

432

449

480

462

441

357

470

520

506

506

294

166

259

Suspended sediment

Mean 

percent

0.31

.22

.33

.26

.25

.23

.20

,30

.26

.23

.21

.26

;24

.21

.18

.19

.15

.16

.17

.24

.22

.20

.20

.17

.18

.20

.15

.07

.05

.03

.16

Tons per 

day

4,870

3,490

4,760

3,820

3,770

3,200

2,760

4,140

 3,950

3, 410

3,060

3,620

3,160

2,870

2,460

2,480

1,920

1,900

1,980

2,910

2,850

2,500

2,380

1,640

2,280

2,810

2,050

956

397

' 134

1,120

83,650

1940

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....

January

266

332

441

794

' 981

830

776

708

633

654

794

890

1,620

1,120

782

530

453

462

432

354

400

502

428

278

420

563

670

764

649

602 «£-

0.09

.20

.63

.65

.43

.23

.44

.47

.24

.24

.54

.71

1.41 '.85

.51

.35

.29

.36

.23

.16

.30

.44

.23

.19

.27

.52

.49

.38

.37

.33

.35

Mpottdy load, items) . .

646

1,790

7,500

13,900

11,400

5,150

9,220

8,980

4,100

4,240

11, 600

17, 100

61, 700

25, 700

10,800

5,010

3,550

4,490

2,680

1,530

3,240

5,960

2,660

1,430

3,060

7,900

8,860

7,840

6,480

5,360

6,130

270. 000

February

670

1,130

1,690

1,960

1,480

994

860

747

643

633

602

558

539

558

558

530

544

582

582

502

525

558

534

582

649

788

1,060

1,880

2,220

0.36

1.27

1.58

1.28

1.87

1.12

1.04

.84

.70

.86

.53

.55

.55

.44

.42

.35

.34

.43

.39

.23

.24

.36

.22

.38

.32

.51

1.01

7.28

4.24

4,700

38,700

72, 100

67, 700

74, 700

30, 000

24,200

16, 900

12,200

14,700

8,610

8,290

8,000

6,630

6,330

5,000

4,990

6,760

6,130

3,120

3,400

5,420

3,170

5,970

5,610

10,800

28,900

370, 000

254, 000

1.107. onn

March

1,870

1,520

1,530

1,220

1,090

981

890

962

878

800

830

1,190

1,120

1,030

776

659

612

617

818

968

988

1,020

1,080

1,220

1,410

1,710

1,770

2,220

2,040

1,990

1,620

2.89

2.13

2.12

1.25

.93

.86

.73

.67

.54

.53

.52

.94

.63

.65

.67

.60

.46

.41

.63

.54

.61

.65

.61

.64

1.25

.80

1.13

1.37

.85

.91

.63

146, 000

87,400

87,600

41,200

27,400

22,800

17,500

17,400

12,800

11,400

11,600

30,200

19,000

18,100

14,000

10,700

7,600

6,830

13,900

14,100

16,300

17,900

17,800

21,100

47,600

36,900

54,000

82,100

46,800

48,900

27,600

1.035,000
138 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended sediment in the San Juan River at gaging station near Bluff, Utah. 

Oct. 1, 1929, to Sept. 80, 1941 Continued

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

1

April

Mean 

discharge 

(secondfeet)

1,420

1,330

1,500

1,460

1,410

1,230

1,200

1,260

1,200

1,170

1,140

1,090

1,100

1,120

1,200

1*720

2,520

2,510

2,220

1,900

1,730

2,340

3,200

3,410

4,450

4,230

3,710

3,570

3,780

3,030

Monthly IOE

Suspended sediment

Mean 

percent

0.68

.44

.52

.51

.48

.40

.39

.45

.34

.42

.33

.34

.33

.45

.43

.66

.93

.72

.65

.57

.49

.77

.79

.79

.93

.88

.78

.75

.71

.66

d (tons)..

Tons per 

day

26, 100

15,800

21, 100

20, 100

18, 300

13, 300

12,600

15, 300

11,000

13, 300

10, 200

10, 000

9,800

13, 600

13, 900

30, 700

63,300

48,800

39,000

29,200

22,900

48,600

68, 300

72, 700

112,000

100, 000

78, 100

72,300

72,500

54, 000

1, 137, 000

May

Mean 

discharge 

(secondfeet)

2,510

2,320

1,910

2 030

2^520

3,990

4,930

4,930

5,270

5,010

5,100

5,690

5,950

6,030

5,990

6,620

6,620

6,440

6,800

6,530

4,960

4,640

4,020

3,870

3,720

3,940

4,300

4,380

4,780

4,940

4,850

Suspended sediment

Mean 

percent

0.65

.52

.51

.37

.44

.73

.96

.93

.82

.88

.82

.78

1.15

.79

.94

.86

1.14

.64

.67

.82

.69

.64

.53

.69

.75

.56

.57

.49

.66

.61

.70

Tons per 

day

44,100

32,600

26,300

20,300

29,900

78,600

128, 000

124, 000

117, 000

119,000

112,900

119, 800

185, 000

128,600

152, 000

153, 000

204,000

111,000

123,000

145,000

92,400

80,200

57,500

72, 100

75, 300

59,600

66,200

57,900

85,200

81,400

91, 700

2, 974, 000

June

Mean 

discharge 

(secondfeet)

4,990

5,250

5,180

4,930

4,100

3,860

3,270

2.-860

2,560

2,270

2,060

1,880

1,650

1,600

1,530

1,490

1,550

1,460

1,370

1,300

1,100

1,040

955

916

910

848

854

697

724

623

Suspended sediment

Mean 

percent

0.46

.36

.24

.57

.62

.44

.54

1.36

.34

.45

.20

.21

.35

.19

.22

.32

.22

.20

.24

.22

.13

.09

.15

.13

.15

.11

.16

.15

.15

.13

Tons per 

day

62,000

51,000

33,600

75,900

68,600

43,500

47, 700

105,000

23,500

27,600

11,100

10, 700

15,600

8,210

9,090

12,900

9,210

7,880

8,880

7,720

3,860

2,530'

3,870

3,220

3, 690

2,520

3,690

2,820

2,930

2,190

670,900

1940

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....

, 1

July

913

549

719

854

659

558

416

388

328

301

281

235

196

150

118

118

280

218

77

46

74

253

150

100

78

51

552

1,430

3,140

2,220 

890

Monthly los

0.09

.30

.44

.33

.22

.21

.31

.12

.12

.12

.06

.07

.05

.04

.03

2.88

3.36

9.45

5.42

3.34

1.35

1.75

1.54

.69

.17

.11

.08

5.93

15.3

7.23 

5.74

d (tons) -

2,200

4,450

8,540

7,610

3,910

3,160

3,480

1,260

1,060

975

455

444

265

162

96

9,180

25,400

55,600

11, 300

4,150

2,700

12, 000

6,240

1,860

358

151

1,190

229, 000

1, 297, 000

433, 000 

138, 000

2. 265, 000

August

384

224

148

112

93

74

52

47

120

339

154

124

114

96

83

62

59

54

41

31

137

154

328

1,650

4,500

6,300

2,930

974

994

697 

602

4.44

3.76

3.20

1.63

.65

.35

.20

.14

2.09

3.72

. 4.12

3.92

3.26

2.12

1.07

.50

.83

.53

.30

2.13

3.23

3.36

5.60

10.8

16.3

8.97

5.68

5.36

4.11

2.68 

2.28

46,000

22, 700

12, 800

4,930

1,630

699

281

1,780

6,770

34,000

17,100

13,100

10, 000

5,500

2,400

837

1,320

773

332

1,780

12,000

14, 000

49,600

481,000

1, 980, 000

1, 280, 000

449,000

141, 000

110, 000

50,400 

37, 100

4, 789, 000

September

506

462

388

380

318

361

269

199

202

181

157

139

678

281

275

194

311

3,000

3,330

5,450

2,930

4,880

4,100

2,770

2,220

2,090

1,710

1,710

6,170

12, 130

1.18

1.02

.63

.79

.80

.82

.61

1.86

1.43

.54

.33

.33

7.13

5.47

10.1

4.02

3.38

7.02

11.0

7.98

5.42

7.30

6.14

6.52

2.41

1.60

1.37

.99

9.92

12.1

16,100

12,700

6,600

8,110

6,870

. 7,990

4,430

9,990

7,800

2,640

1,400

1,240

130, 000

41,-SOO

75,000

21,100

28,400

569,000

989,000

1,174,000

429,000

962,000

680,000

488,000

144,000

90, 300

63, 300

45,700

1,653,000

3,960,000

11, 630, 000
QUANTITIES OF SUSPENDED SEDIMENT 139

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended 

sediment in the San Juan River at gaging station near Bluff, Utah, Oct. 1, 1929,

to Sept. SO, 1941 Continued

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....

October

Mean 

discharge 

(secondfeet)

9,820

4,100

3,100

2,340

5,590

6,240

3,310

3,990

3,000

2,650

2,290

2,140

1,900

1,750

1,590

1,530

1,440

1,370

1,270

1,250

1,210

1,110

1,030

903

818

878

1,900

1,410

1,080

1,370

1,150

Suspended sediment

Mean 

percent

12.5

4.13

4.27

1.93

7.94

4.01

2.85

2.23

1.50

1.28

1.06

.77

.78

.73

.64

.61

".60 .43

.63

.42

.54

.50

.53

.40

.43

.40

1.80

1.37

.82

.95

.69

Monthly load (tons) . .

Tons per 

day

3, 320, 000

457,000

357,000

122, 000

1, 200, 000

676*600?

255,000

240,000

122, 000

91, 600

65,500

44,500

40,000

34,500

27,500

25,200

16, 700

22,200

22,400

14,700

18,300

15,500

14, 700

9,750

9,500

9,480

92,300

52,200

23,900

35, 100

21, 400

7,456,000

November

Mean 

discharge 

(secondfeet)

1,060

1,000

981

988

903

884

896

884

812

788

836

916

903

903

794

747

742

794

2,780

3,260

1,930

1,560

1,300

1,130

1,050

994

974

936

910

903

Suspended sediment

Mean 

percent

0.77

.62

.73

.58

.63

.53

.31

.40

.44

.42

.50

.46

.50

.66

.33

.30

.45

.39

3.86

2.50

1.38

1.00

1.45

1.17

.96

.84

.90

.55

.66

.56

Tons per 

day

22,800

16,700

19, 300

15,500

15,400

12,600

7,500

9,550

9,650

8,940

11,300

11, 400

12,200

16,100

7,070

6,050

9,020

8,360

290, 000

220,000

71,900

42,100

50,900

35, 700

27,200

22,500

23,700

13,900

16,200

13,600

1, 047, 000

December

Mean 

discharge 

(secondfeet)

878

854

848

878

866

872

848

848

884

878

1,010

1,150

1,950

1,760

1,370

974

878

759

1,430

1,450

1,290

1,250

1,030

948

3, 110

2,960

2,070

1,420

1,170

1,760

2,620

Suspended sediment

Mean 

percent

0.56

.53

.57

.79

.44

.46

.60

.43

.51

.60

.58

.61

1.21

1.42

1.52

'1.13

.61

.50

3.75

2.47

11.50

1.07

.89

.57

2.49

4.55

2.77

2.17

1.68

2.33

2.14

Tons per 

day

13,300

12,200

13,000

18,700

10,300

10,800

13,700

9,850

12,200

14,200

15,800

. 18,900

63,700

67,500

56,200

29,700

14,500

10,200

145, 000

96,700

52,200

36,100

24,800

14,600

209,000

364,000

155,000

83,200

53,100

111,000

151,000

1, 900, 000

1941

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....

January

3,200

2,590

1,850

1,320

1,100

910

836

818

788

788

830

981

1,360

1,420

1,920

1,450

1,150

974

836

776

747

842

1,080

1,090

1,240

1,660

1,280

1,170

1,260

1,500

1,440

3.43

3.28

2.48

1.89

1.11

.90

.79

.71

.92

.89

.85

.75

1.70

1.81

1.51

1.93

' 1.53

1.11

1.03

.90

.66

.58

1.23

.95

.93

1.53

1.23

1.18

1.20

1.19

.90

Monthly load (tons)..

296,000

229, 000

124,000

67, 400

33, 000

22, 100

17,800

15,700

19,600

18,900

19, 100

19,900

62,400

69,400

78, 300

75,600

47,500

29,200

23,200

18,900

13,300

13,200

35,900

28,000

31, 100

68,600

42,500

37, 300

40,800

48, 200

35,000

1, 681, 000

February

1,340

1,220

1,280

1,160

955

903

1,120

1,710

1,520

1,330

1,200

1,460

1,680

1,660

1,580

1,550

1, 710

1,920

2,930

2,990

4,290

4,670

4,770

4,080

4,140

4,110

3,690

2,910

0.89

.70

.93

.88

.80

.75

.63

1.47

.93

.80

.97

1.05

1.23

1.05

1.37

1.61

1.57

1.89

2.53

2.44

3.38

3.24

3.98

3.43

2.82

3.05

2.62

2.19

32,200

23,100

32, 100

27,600

20,600

18,300

19,000

67, 900

38,200

28,700

31,400

41,400

55,800

47, 100

58,400

67, 400

72, 500

98,000

200, 000

197, 000

392, 000

409,000

513, 000

378, 000

315, 000

338, 000

261, 000

172, 000

3, 955, 000

March

2,080

1,890

2,220

3,400

2,440

2,090

2,330

2,320

1,960

1,760

1,660

1,520

1,520

1,670

4,700

4,290

4,460

4,560

4,200

4,400

4,820

4,500

5,500

5,640

5,640

5,990

4,590

3,690

3,220

3,500

3,960

1.85

1.16

1.38

2.14

1.54

1.38

1.96

1.45

1.25

1.13

.87

.74

.83

.82

6.09

5.62

3.20

2.99

3.25

3.19

3.16

2.28

2.89

2.70

2.88

2.55

1.74

1.61

1.93

1.36

1.82

104, 000

59,200

82,700

196,000

102,000

77,900

123,000

90,800

66,200

53,700

39,000

30,400

34,100

37,000

773,000

651,000

385,000

368,000

369, 000

379,000

411,000

277, 000

429,000

411,000

439,000

412,000

216, 000

160,000

168,000

128,000

195,000

7, 267, 000

1 Estimated.

725606 4.7- -10
140 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 18. Mean daily discharge, mean concentration, and daily load of suspended sediment in the San Juan River at gaging station near Bluff, Utah, 

Oct. 1, 1929, to Sept. SO, 1941^-Continued

1941

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

Mean 

discharge 

(secondfeet)

4,450

5,800

7,250

5,240

4,480

4,260

4,530

4,080

4,020

4,380

5,270

6,330

6,330

6,330

5,800

4,900

4,930

4,690

4,750

4,610

4,380

4,120

6,150

7,630

6,150

7,560

13,000

14,800

16,800

14,800

Suspended sediment

Mean 

percent

1.72

2.27

2.26

1.79

1.25

1.54

1.62

1.10

1.06

1.35

1.84

1.30

1.42

1.55

1.49

1.04

1.02

1.24

1.24

1.14

1.18

.99

3.64

2.19

1.78-

3.74

7.20

6.66

3.04

2.36

Monthly load (tons) 

Tons per 

day

207, 000

355, 000

442, 000

253,000

151, 000

177,000

198,000

121, 000

115,000

160,000

262, 000

222,000

243,000

265, 000

233,000

138, 000

136, 000

157,000

159, 000

142, 000

140,000

110,000

604,000

451,000

311,000

763, 000

2,530,000

2, 660, 000

1,380,000

943,000

14,030,000

May

Mean 

discharge 

(secondfeet)

14 400

14', 100

20, 000

20,000

27, 100

25, 700

20,500

21, 600

&LI 91 finn ouu

23,500

25,200

26, 000

28,000

33,800

32,600

28,300

22,900

22,100

22,600

22, 600

18,100

15, 100

15,800

25,200

18,900

18, 900

18,400

18,400

16,600

14,600

14,400

Suspended sediment

Mean 

percent

2.05

1.71

2.70

2.59

3.59

3.76

3.06

3.08

2.86

3.05

2.59

2.28

2.40

2.33

2,23

1.80

1.59

1.40

1.43

1.24

1.01

.92

1.34

4.96

4.82

3.59

2.09

1.44

.93

1.07

1.05

Tons per 

day

797,000

651,000

1 460 000 1^400! ooo

2, 630, 000

2, 610, 000

1, 690, 000

1, 800, 000

1,670,000

1, 940, 000

1, 760, 000

1,600,000

1,810,000

2, 130, 000

1,960,000

1,380,000

983,000

835,000

873,000

757, 000

494,000

375, 000

572, 000

3, 370, 000

2,460,000

1, 830, 000

1,040,000

715,000

417,000

422,000

408,000

42, 830, 000

June

Mean 

discharge 

(secondfeet)

13, 400

12,900

12,900

13,400

13,900

13,900

15,100

14,100

18, 900

20,200

17,900

14,100

11,400

11, 100

11,400

12,000

12,500

13,400

14,400

16,600

18,100

18,400

18, 400

18,600

20,000

20,200

17, 900

16,600

15,600

14,100

Suspended sediment

Mean 

percent

0.91

1.17

.82

1.12

.87

.94

1.04

1.26

1.37

1.63

1.18

1.01

.77

.66

.62

.68

.69

.75

.75

.87

.79

.84

.74

.77

.87

.94

.81

.79

.79

.73

Tons per 

day

OAi7, QOQ UUU OAA

Ana rinn Ttuo, \nj\j

286,000

405,000

327,000

353,000

424,000

480,000

699,000

889, 000

570, 000

385,000

237,000

198,000

191, 000

247,000

233,000

271,000

292,000

390,000

386,000

417, 000

368,000

387,000

470, 000

513, 000

391,000

354,000

333,000

278,000

.... .... - -.-.-111,510,000

1941

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..-

July

12,900

12,200

11,600

11,400

11,600

12,000

12, 500

11,100

10,300

10,300

10,500

10,000

10,000

9,840

9,210

8,410

7,630

7,060

6,690

7,250

7,440

7,060

6,330

6,690

6,150

6,510

5,560

4,740

4,510

4,120 

3,580

0.83

.75

.69

.57

.66

.73

.81

.74

.69.

.71

.68

.54

.56

.61

.59

.44

.36

.41

.37

.40

.51

.79

.44

.51

.71

1.17

.98

.46

.37

.29 

.38

Monthlyload (tons) 

289,000

247, 000

216, 000

175,000

207,000

237,000

273,000

222,000

192, 000

198, 000

193,000

146, 000

151, 000

162,000

, 147,000

99,900

74,200

78,200

66,800

78,300

102,000

151,000

75,200

92,100

118,000

206,000

147,000

58,900

45, 100

32,300 

36,700

4,517,000

August

3,110

2,850

2,560

2,420

2,280

2,090

1,910

2,480

3,380

8,370

7,010

3,870

2,860

2,440

3,800

5,800

4,850

3,740

3,400

2,700

2,290

1,960

1,760

1,600

1,470

1,330

1,200

1,140

1,060

1,000 

903

0.30

.39

.30

.28

.14

.10

.14

.44

1.09

6.79

9.93

3.86

1.40

.75

.63

4.18

4,25

2.29

1.43

1.45

.60

.40

.33

.31

.27

.23

.18

.22

.19

.25 

.22

25,200

30,000

20,700

18,300

8,620

5,640

7,220

29,500

99,500

1, 530, 000

1,880,000

146,000

108,000

49,400

64,600

655,000

557,000

231,000

131,000

106,000

37,100

21,200

15,700

13,400

10,700

8,260

5,830

6,770

5,440

6,750 

5,360

5,839,000

September

922

948

922

836

788

854

638

664

659

623

617

628

759

3,370

5,100

5,290

3,570

3,110

4,060

3,150

4,780

5,630

12,700

11,800

6,330

4,480

3,750

3,380

3,360

8,220

0.20

.21

.15

.15

.12

.15

.10

.09

.12

.11

.13

.10

.10

7.64

7.17

6.51

3.80

2.10

5,49

3.17

2.94

2.98

6.49

6.02

1.63

1.16

.67

.60

.56

3.46

.. .. . 

4,980

5,380

3,730

3,390

2,550

2,460

1,720

1,610

2,140

1,850

2,170

1,700

2,050

695,000

987,000

930,000

366,000

176,000

602,000

270,000

379,000

453,000

2,220,000

1,920,000

279,000

140,000

67,800

54,800

50,800

768,000

10,390,000
QUANTITIES OF SUSPENDED SEDIMENT 141

TABLE 19. Suspended-sediment concentration in individual samples collected from 

the San Juan River at gaging station near Bluff, Utah, in Sept. and Oct. 1937, 

Sept. 19S9, July to Oct. 1940, and March, April, and September 1941

Sampling points, measured from zero mark on cable at north bank: A, one-fourth, the 

distance across the river; B, one-half; C, three-fourths.

Date of 

collection

1937 

Sept. 26 _ . ........

Sept. 27..... ....

Sept. 28 

Sept. 29... _ ...

Sept. 30... ....

Oct. 1 _______ 

Oct. 2. __ . _ .....

Oct. 3..............

Oct. 4.. ........ 

Oct. 5............ ; Oct. 6..... __ ..... 

Oct. 7... ....... _ .

19S9 

Sept. 10 ______ 

Sept. 11 ___ ......

Sept. 12..,. __ .... 

Sept. 13... ... ......

Sept. 14. _____ .

Sept. 15. ___ ..... 

Sept. 16.. . _ .

1940 

July 15 ______ 

July 16 ....... ...

July 17.............

July 18.............

July 19.. _ .......

July 20.. ...........

July 21.............

July 22.... .........

Aug. 21............ 

Aug 22

Aug. 23............ 

Aug. 24 ............

Aug. 25.. .......... 

Aug. 26.. .......... 

Aug. 27 __ . _ ....

Time

8:15 a. m. _ . ......

8:10 p. m ...........

9:15 a.m.. ___ ... 

2:20 p.m. __ . .....

7:50 p. m ............

11:45 p.m...........

6:30 a.m.... _ . _ . 

12:30 p. m ...........

11:45 p.m..... ......

12:00 m. _ ... __ ...

10:10 a.m. ..........

4:45 p. m ............

2:30 p. m ______ .

5:40 p. m ............ 

1:00 p. m ............ 

6:00 p.m. ...........

10:00 p. m ...........

10:00 a.m..... ...... 

6:00 p. m ............

3:30 p.m.. ..........

9:30 p.m. __ . __ .

11:00 a.m..

10:00 a.m. _ .. __ . 

1:30 p. m _ . _ .....

7:00 p. m _ . ___ . 

5:00 p.m. ___ ..... 

8:15 p. m ___ ....

15:40 p. m ____ .. 

11:20 p.m...... .....

1:00 p. m ___ . ..... 

8:00 p. m .....

10:40 a. m ..........

7:20 a.m. _____ .

9:10 a.m. __ ....

11:15 p.m...........

6:10 a.m.. __ . _ .. 

3:10 p.m......... ..

9:45 p. m ___ . _ .

9:35 a.m. _____ . 

1:45 p. m ............

9:20 p.m... .........

7:25 a.m.... ........ 

5:25 p. m ____ .

8:25 p. m ............

11:200. m.. .........

Gage 

height

4.02 

4.16 

4.20 

4.22 

4.80 

8.00 

U3.00 

15.30 

15.40

1 16. 70 

16.00 

12.10 

10.15 

8.45 

6.40 

5.48 

5.10 

4.90 

4.85

4.90 

6.70 

9.60 

10.80 

13.00 

11.80 

9.60 

8.90 

8.20 

7.60 

7.30 

7.40

"sTio"

3.40 

4.70 

4.20 

3.30 

2.76 

2.60 

3.43 

3.77

3.26 

3-30 

3.40 

3.80 

6.05 

6.52 

7.68 

7.82 

8.20 

7.28 

9.65 

9.70 

8.02 

7.03 

7.00 

7.05 

7.01

Suspended sediment

At sampling points 

A

(percent)

0.36 

.43 

.56 

.41 

1.34 

5.88 

16.8 

16.1 

14.2

14.8 

17.4 

13.1 

10.5 

7.88 

4.65 

3.06 

2.09 

1.17 

.89

2.50 

2.86 

4-26 

6.23 

15.9 

25.7 

5.22 

5.05 

5.12 

3.17 

1.88 

1.41

.02 

'1.25 

4.79 

1.40 

4.74 

9.73 

4.15 

4.29 

1.56 

2.55

3.37 

4.10 

2.46 

- 5.83 

5.91 

9.02 

16.3 

13.3 

12.3 

21.0 

11.7 

8.68 

6.48 

5.20 

5.09 

5.22 

5.26

B

(percent)

0.34 

.40 

.48 

.40 

1.39 

6.02 

15.8 

17.4 

14.3

15.2 

17.5 

13.4 

10.8 

8.09 

4.70 

3.12 

2.08 

1.26 

.88

2.58 

3.86 

4.77 

7.22 

17.8 

26.4 

5.84 

5.77 

5.27 

2.89 

2.55 

1.17

.03 

1.21 

4.24 

1.41 

5.17 

9.30 

5.94 

2.83 

.99 

1.29

3.24 

4.18 

2.63 

5.93 

6.02 

8.48 

17.8 

12.5 

11.7 

25.6 

11.4 

8.89 

6.64 

5.47 

5.36 

5.66 

5.58

C

(percent)

0.46 

.38 

.37 

.44 

1.08 

5.03 

15.8 

17.8 

14.2

15.4 

17.9 

13.5 

11.2 

7.87 

4.70 

3.08 

2.01 

1.19 

.95

2.21 

3.24 

5.29 

7.92 

18.6 

21.2 

6.60 

6.81 

4.46 

3.48 

3.53 

1.22

.03 

1.38 

4.38 

2.82 

4.71 

9.31 

6.16 

2.90 

1.50 

1.41

3.08 

4.39 

2.42 

.5.04 

6.08 

8.87 

18.4 

16.5 

9.17 

25.5 

9.97 

9.45 

7.48 

7.20 

5.26 

7.32 

5.58

Mean 

daily 

percent

0.39 

.40 

.47

.84

13.3

14.2

7.95 

4.68 

3.09 

2.06 

1.21 

.91

" 2.43 

5.07

20.9 

5.57

3.18 

2.65 

1.27

.03

2.88

3.36

9.45 

5.42 

3.34 

1.35 

1.75

3.23 

3.36

5.60 

10.8

16.3 

8.97 

5.68

Tons per 

day

1,450 

1,830 

2,610 

5,560

2,840,000

5,370,000

979,000 

286,000 

113,000 

57,800 

29,700 

20,900

71,500 

556,000

6,210,000 

1,070,000

326,000 

245,000 

118,000

96 

9,180

25,400

55,600 

11,300 

4,150 

2,700 

12,000

12,000 

14,000

49,600 

481,000

1,980,000 

1,284,000 

449,000

i Estimated.
142 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 19. Suspended-sediment concentration in indivudual samples collected from 

the San Juan River at gaging station near Bluff, Utah, in Sept. and Oct. 1937, 

Sept. 1939, July to Oct. 1.940, and March, April, and September 1941 Continued

Sampling points, measured from zero mark on cable at north bank: A, one-fourth, the 

distance across the river ; B, one-half; C, three-fourths.

Date of 

collection

1940 

Aug. 28.... 

Aug. 29.... .....

Aug. 30 - . 

Aug. 31-.. 

Sept. 15 

Sept. 20 ... ......

Sept. 22 

Sept. 23 

Sept. 24... .........

Sept. 25 

Sept. 26_ . . 

Sept. 27 

Sept. 28 

Sept. 29----.----,..

Sept. 30 - 

Oct. 1 ..... ... ...

Oct. 2 ...... ..... 

Oct. 3. 

1941 

Mar. 14......... .

Mar. 15.. ... . 

Mar. 16..-...-.-...

i Estimated.

Time

7:50 p. m ............

9:25 a. m ............

3:00p.m ............ 

3:20 p. m ............

10:25 a. m. ..........

10:10 a. m. ..........

12:40 a. m. ..........

11:15 a. m. .-.-.- .

4:20 p. m __ . .......

6:35 p. m__ ..........

11:15 p. m_. ..---. ...

11:25 a. m... ........

10:00 a. m. .......... 

3:30 p. m ............

10:30 p. m ...........

7:25 a. m._ ..........

5:15 p. m ............

10:00 a. m. ..........

11:45 a. m... .... ... .

2:00 p. m.... ........ 

2:30 p. m.. .......... 

3:00 p. m_ _ . ....... 

12:20 p. m.. .........

5:05 p. m. _____ .

9:05 a. m.. _____ .

6:40 p. m ............

6:35 a. m.... ... .... .

11:40 &. m. ..........

4:45 p. m. __ __ ..

2:55 p. m.. _ _ ....

11:15 a. m. ........ ..

10:20 a. m. _____ .

3:45 p. m ____ _

11:30 p. m ...........

5:25 p. m.. ......... .

Qage 

height

6.30 

5.99 

5.67 

5.11 

4.57 

4.35

3.20 

4.47 

4.82 

4.92 

4.40 

3.80 

4.71 

4.10 

3.90 

5.48 

7.95 

7.05 

7.05 

7.02 

7.40 

7.35 

7.65 

9.20 

10.25 

. 9.15 

8.40 

7.30 

7.25 

7.00 

6.95 

'8.30 

11.50 

U0.50 

18.45 

7.40 

7.30 

6.80 

6.30 

5.97 

5.67 

10.05 

8.65 

8.70 

11.60 

10.20 

10.40

11.50 

9.90 

8.60 

7.95 

7.55

5.68 

8.40 

8.55 

8.40 

8.15 

8.70 

7.30

Suspended sediment

At sampling points 

A 

(percent)

4.94 

5.83 

5.26 

4.08 

2.78 

2.98

0.32 

3.57 

13.6 

3.19 

4.28 

1.39 

9.10 

10.6 

3.31 

6.41 

6.64 

8.09 

6.27 

16.6 

10.6 

8.33 

8.92 

8.84 

7.03 

6.50 

8.20 

6.22 

5.62 

4.07 

3.14 

3.91 

7.00 

13.1 

7.92 

3.70 

5.26 

^ 2.47 

1.59 

1.27 

.86 

11.3 

10.1 

7.87 

14.2 

10.6 

6.56

8.21 

18.6 

8.91 

3.84 

3.29

.79 

6.61 

6.27 

5.62 

4.48 

5.44 

5.27

B

(percent)

5.12 

5.38 

5v8l 

4.28 

2.67 

1.66

0.31 

3.52 

16.5 

3.02 

4.32 

1.80 

10.5 

10.3 

3.55 

6.34 

5.' 32 

9.09 

6.24 

14.7 

11.4 

8.83 

11.8 

9.49 

7.26 

7.01 

8.49 

6.54 

6.11 

3.91 

3.18 

4.53 

9.06 

14.9 

7.59 

4.71 

7.08 

2.34 

1.65 

1.62 

1.03 

10.6 

10.2 

8.39 

13.4 

9.63 

7.70

10.2 

23.0 

8.78 

4.30 

5.94

.93 

6.98 

6.91 

6.29 

4.82 

5.96 

5.31

C

(percent)

5.00 

5.92 

4.97 

3.98 

2.58 

2.19

0.35 

3.38 

21.9 

4.12 

4.17 

1.09 

8.94 

9.43 

3.28 

8.58 

6.35 

8.28 

6.61 

13.5 

10.7 

9.16 

7.35 

9.32 

7.67 

7.39 

8.58 

6.32 

5.63 

4.34 

3.46. 5.03* 

8.07 

12.2 

8.12 

4.78 

7.23 2.42- 

1.55 

1.23 

1.08 

11.9 

10.8 

8.14 

14.7 

9.93 

13.1

10.0 

16.1 

8.84 

4.25 

3.57

.73 

6.21 

7.15 

6.34 

5.36 

6.28 

5.47

Mean 

daily 

percent

6.36

4.11 

2.68 

2.28

0.33 

7.13

5.47

10.1 

3.38 

7.02

11.0 

7.98

5.42 

7.30

6.14

6.52 

2.41 

1.60 

1.37 

.99 

9.92

12.1

12.5

4.13

4.27

.82 

6.09

5.62

Tons per 

day

141,000

110,000 

50,400 

37,100

1,240 

130, 000

41,500

75, 000 

8,400 

569, 000

989,000 

1, 174, 000=

429,000 

962,000

680,0(M>

488,000' 

144,000 

90,300 

63,300 

45,700 

1, 653, 000

3, 960, 00»

3, 320, 000

457,000 

357, OOa

37,000 

773, 000

651,000
QUANTITIES OF SUSPENDED SEDIMENT 143

TABLE 19. Suspended-sediment concentration in individual samples collected from 

the San Juan River at gaging station near Bluff, Utah, in Sept. and Oct. 1937, 

Sept. 1939, July to Oct. 1940, and March, April, and September 1941 Continued

Sampling pewits, measured from zero rtark on^eable at-north bank: A, one fourth, the distance across the 

fiver; B, one-half; C, three-fourths.

Date of 

collection

1941 

Mar. 17 

Mar. 18. 

Apr. 22.. ..........

Apr. 23 -

Apr. 24..... ........

Apr. 25.. ..........

Apr. 26... .... .....

A.pr. 27 ............

Apr. 28 .... ......

Ap. 29 ...... 

Apr. 30 _ ..... 

Sept. 13 ........

Sept. 14 . 

Sept. 15-... .......

Sept. 16............

Sept. 17 . 

Sept. 18... __ . ....

Time

10:40 a. m. . _ ....

3:30 p. m _ .. . ......

8:40 a. m.. ..........

6:50 p.m.... ........

9:45 a. m... . ___ .

9:50 a. m.. ___

9:30 p.m. _ . .......

7:45 a.m. ...........

3:15 p. m__. ... ..... _

6:50 p. m.. ...... .. ..

8:50 p. m... .........

7:40 a. m'.. .......... 

1:30 p.m.. ..........

4:15 p. m ............

8:15 p.m.. ......... .

6:50 a. m. ........ ...

6:50 a. m. . ...... . 

5:00 p. m.. ..........

9:05 a. m. _ .. __ ..

5:50 a.m..... .....

12:45 p. m _____ ..

6:10p. m... ....... ..

11:20 a. m.. .........

9:45 p. m.. ..........

5:40 a. m._ .......... 

6:15 p.m. . ........

5:55 a. m._ _ .......

11:10 a. m.-... ...

Gage 

height

8.10 

8.15 

7.65 

8.21

7.45 

8.42 

9.25 

9.50 

9.90 

9.58 

9.25

aso

8.88 

9.95 

10.23 

11.15 

10.64 

12.85 

14.50 

12.00 

12.32 

13.30 

14.20 

13.30

4.60 

10.60 

7.68 

6.82 

7.27 

9.30 

9.68 

9.50 

8.27 

8.00 

6.69

Suspended sediment

At sampling points 

A 

(percent)

3.10 

2.33 

2.16 

3.22

.89 

4.38 

2.92 

2.04 

2.02 

1.43 

1.44 

1.65 

1.57 

2.47 

5.32 

10.0 

9.16 

4.92 

3.61 

8.34 

3.92 

3.17 

3.02 

2.18

.08 

10.3 

7.98 

5.06 

3.68 

9.01 

7.77 

7.09 

5.64 

3.93 

2.04

B

(percent)

3.56 

2.89 

2.25 

3.79

1.06 

4.87 

3.53 

3.10 

2.65 

2.01 

2.19 

1.98 

2.00 

3.44 

6.52 

10.8 

7.99 

5.92 

3.98 

9.22 

5.27 

3.25 

 2.69 

2.31

.10 

10.1 

8.44 

5.10 

3.46 

9.20 

10.3 

7.79 

5.41 

3.70 

2.08

C

(percent)

4.28 

3.05 

2.50 

4.01

1.02 

4.97 

3.74 

3.25 

2.68 

2.21 

3.05 

1.98 

2.00 

3.53 

6.79 

11.2 

7.66 

6.33 

4.89

6.56 

3.46 

2.68 

2.59

.11 

9.84 

7.01 

4.89 

3.50 

8.40 

9.18 

7.65 

5.50 

3.78 

2.18

Mean 

daily 

percent

3.20 

2.99

.99 

3.64

2.19

1.87 

3.74

7.20

6.66 

3.04 

2.36

.10 

7.64

7.17

6.51

3.80 

2.10

Tons per 

day

385,000 

368,000

110, 000 

604,000

451,000

311, 000 

763,000

2, 530, 000

2, 660, 000 

1, 380, 000 

943, 000

2,050 

695,000

987,000

930,000

366,000 

176, 000
144 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 20. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment 

in Little Colorado River at gaging station at Grand Falls, Ariz., July 6 to Sept. %6t 

1931

Date

1931 

July 6..... ..........

July 7_.._ ...........

July 10.... ._

July 11 ... .... ... . 

Julyl2.._ ... _ .. 

July 13....... ....... 

July 14. 

July 16 

July 17....... . ...

July 18......... ..

July 19.... ..........

July 20.............. 

July 21....... .......

July 22..... .........

July 23-.... .

July 24......... 

July 25.............. 

July 26 . 

July 27... ........

July 28... . .... 

July 29..... ... ... ...

July 30.... ....... 

July 31.......... ....

Aug. 1... ......... ..

Aug. 3-..-..-..---..

Aug. 4. ....... .. 

Aug. 5... . ..

Aug. 7...... ........

Aug. 8-......--.--..

Aug. 9-... ... 

Aug. 10.. ...........

Aug. 11..... ........

Aug. 12............. 

Aug. 13.... ......

Aug. 14.............

Aug. 15. 

Aug. 16__._. ........

Aug. 17.............

Time of collection

12:30 p. m.. ___ ..

11:20 a. m. ....... ...

11:10 a. m... --.-.-.. 

11:55 a. m. .......... 

2:30 p. m ......... 

12:30p. m.-._ ..---..

11:00 a. m... ___ -

10:10 a. m. ..........

1:35 p. m. ...........

11:00 a. m. --.-.-.-..

10:25 a. m_. ____ .

11:40 a. m-. ... 

11:00 a. m 

2:15 p. m- ...........

11:05 a. m_. .........

12:15 p. m... ........

10:40 a. m._- __

10:30 a. m. __._ ._._. _

3:05 p. m ............

12:00 m. _ ..........

10:40 a. m... _ .....

1:20 p. m ............

11:45 a. m. ... ....

12:45 p. m. ....... 

11:50 a. m _ ........

10:05 a. m... ___ .

11:35 a. m... ___ .

3:20 p. m... ...... 

12:55 p. m ........ 

9:50 a. m... .........

11:20 a. m...... .....

10:45 a. m _ . ___ .

12:25 p. m- ....... 

12:05 p. m._ __ .....

11:00 a. m. ..........

12:00 m.._.... .......

11:10 a. m2:20 D. m. . .....

Mean daily 

discharge 

(sec. -ft.)

292 

134 

20

9 

4 

1 

0 

15

44 

164

292 

599 

1,490

460 

196 

102

148 

346 

215

142 

101

2,300 

1,970

3,680

3,020 

1,110 

550 

428 

1,030

3,580

3,050 

906 

1,310

1,630

468 

312

244

262 

904 

301

Suspended sediment

Number of 

samples

5 

5 

4 

3 

3 

2 

2 

3 

1 

2 

5 

5 

6 

5 

6 

6 

6 

3 

4 

4 

4 

5 

5 

3 

4 

5 

4 

3 

5 

6 

6 

6 

5 

4 

4 

4 

4 

4 

6 

6

6 

5 

7 

4 

5 

5 

6 

6 

5 

5 

6 

5 

4 

4 

4 

5 

3 

5 

4 

4 

6 

5 

5 

5 

5 

5

Mean percent at 

sampling 

period

8.14 

6.87 

7.24 

6.70 

5.91 

3.66 

4.06 

8.01 

1.06 

.48 

3.74 

3.01 

3.87 

4.09 

4.83 

5.50 

7.05 

13.2 

13.4 

11.4 

11.4 

7.96 

7.80 

7.52 

7.52 

6.50 

6.33 

5.89 

7.46 

5.81 

5.93 

6.07 

6.09 

6.03 

6.25 

6.14 

12.2 

11.8 

10.9 

9.82

15.0 

16.0 

11.5 

8.50 

7.17 

6.22 

6.55 

7.37 

11.8 

9.36 

6.98 

4.30 

7.28 

6.93 

7.19 

8.33 

7.63 

5.62 

4.94 

5.11 

4.89 

4.93 

3.87 

5.81 

2.70 

2.43

Mean daily 

percent

8.14 

6.87 

6.97

5.91 

3.66 

4.06

.77 

3.38 

4.26

5.50 

7.05 

12.4

7.88 

7.52 

6.42

5.89 

7.46 

5.87

6.08 

6.14

12.0 

10.4

15.5

11.5 

8.50 

7.17 

6.22 

6.96

10.6

6.98 

4.30 

7.13

7.98

5.62 

5.02

4.91

3.87 

5.81 

2.56

Tons per 

day

64,200 

24,900 

3,760

1,440 

395 

110 

0 

312

4,020 

17,700

43,400 

114,000 

499,000

97,900 

39,800 

17,700

. 23,500 

69,700 

34,100

23,300 

16,700

745,000 

553,000

1,540,000

938,000 

255,000 

106,000 

71,900 

194,000

1,020,000

575,000 

105,000 

252,000

351,000

71,000 

42,300

32,300

27,400 

142,000 

20,800
QUANTITIES OF SUSPENDED SEDIMENT 145

TABLE 20. Suspended-sediment concentration at different sampling times, mean 

daily discharge, mean daily concentration, and daily load of suspended sediment 

in Little Colorado River at gaging station at Grand Falls, Ariz., July 6 to Sept. 26, 

1981 Continued.

Date

1931 

Aug. 18- .. .

A n<r 10

Aug. 21.. ..... ... 

Aug. 22... ........ .. 

Aug. 23.............

Aug. 24. ..... ...

Aug. 25.-.. .....

Aug. 26. ... ..

Aug. 27.............

Aug. 28 .

Aug. 29.... .........

Aug. 30. ..... .... 

Aug. 31.... .........

Sept. 1... ______

Sept. 3. _ . ......

Sept. 5. .... _ ..

Sept. 6 . _____ 

Sept. 7_. ............ 

Sept. 8-, ______ 

Sept. 9... __ ...... 

Sept. 10 . .........

Sept. 11. .........

Sept. 12 ____ . 

Sept. 13 .. ___ . 

Sept. 14... ..........

Sept. 15.. ...........

Sept. 16 ....

Sept. 17 __ . ....

Sept. 18 -

Sept. 19- __ .. __ . 

Sept. 20- __ . __ - 

Sept. 21 .......... 

Sept. 22 .......... 

Sept. 23... ..........

Sept. 24 ......... 

Sept. 25 . 

Sept. 26 

Time of collection

11:00 a.m..... _ ..

10:55 a. m._. _. __ ..

4:30 p. m. ...........

2:10 p. m _____ .

1:25 p. m ___ _ .

10:05 a. m... ___ _

2:25 p. m _____ ..

10:35 a. m. ..........

2:05 p. m ___ . _ .

3:15 p. m _____ .

11:20 a. m. ...... _ .

3:15 p. m ............

12:30 p.m..... _ ... 

10:30 a. m ...........

12:15 p.m... ........

2:45 p. m ............

12:50 p.m. _ . ...... 

3:35 p. m ............

2:40 p. m ............

1:00 p. m ............

3:30 p.m.. _ . __ .

11:55 a.m. .......... 

2:15 p. m ............

11:30 a.m. ......... 

12:00 m... . ____ . 

10:35 a.m.... _ .... 

4:40 p.m. __ . ...... 

11:25 a. m _ .. 

3:00 p.m.. _ . ......

11:15 a. m. ..........

2:45 p.m. ...........

4:00 p. m, __ . ......

11:00 a.m.. _ . __ .

11:30 a. m _ . .......

3:30 p.m...... ......

3:40 p. m ___ ......

10:30 a. m_. ....... ..

11:30 a. m. ..........

2:05 p. m ............

3:05 p. m _ ; ........

11:06 a.m. ..........

2:45 p. m ............

11:40 a. m. _ .. 

11:45 a. m.. ......... 

1:50 p.m............ 

4:55 p. m ______ . 

10:45 a.m. ..........

2:15 p. m ............

10:40 a.m... __ .... 

11:25 a. m. .......... 

9:35 a.m.. _____ .

Mean daily 

discharge 

(sec.-ft.)

244 

180

190 

182 

561

651 

267 

155 

90 

54 

31

22

272

455 

291 

155

113

75

43 

20 

94 

534 

316

160

95 

72 

74

40 

57 

732

514

411 

382 

512 

1,370

474

302

209 

151

Suspended sediment

Number of 

samples

6 

4 

4 

4 

4 

6 

3 

5 

3 

3 

3 

4 

6 

3 

5 

4 

4 

4 

3 

3 

3 

3 

3 

4

5 

4 

5 

4 

5 

3 

5 

3 

3 

3 

4 

4 

4 

4 

4 

5 

 4 

3 

3 

3 

3 

4 

4 

4 

4 

2 

3 

4 

4 

3 

3 

5 

5 

4 

4 

4 

4 

4 

3 

3

Mean percent at 

sampling 

period

1.90 

1.95 

4.21 

4.94 

5.96 

5.27 

6.61 

10.9 

5.52 

5.32 

3.58 

3.48 

3.68 

3.70 

3.58 

155 

2.87 

2.76 

2.26 

2.55 

2.51 

4.79 

4.86 

4.62

4.00 

4.22 

3.72 

3.62 

3.07 

3.25 

2.96 

4.44 

4.16 

3.30 

2.42 

1.97 

5.52 

6.61 

6.35 

5.52 

5.36 

4.72 

5.31 

4.98 

4.58 

3.46 

3.67 

3.59 

3.12 

9.68 

9.34 

8.60 

8.72 

8.61 

8.24 

8.50 

7.79 

5.10 

8.28 

7.27 

7.14 

5.86 

4.07 

2.99

Mean daily 

percent

1.92 

4.58

5.96

5.27 

8.76

5.42 

3.53 

3.69 

3.56 

2.82 

2.40

2.51 

4.76

4.11 

3.67 

3.16

2.96 

4.30

3.30 

2.42 

1.97 

5. 52 

6.48

5.44

4.72 

5.31 

4.78

3.56 

3.36 

9.08

8.42

8.50 

7.79 

5.10 

8.28 

7.20

5.86 

4.07 

2.99

Tons per 

day

12,600 

22,300

30,600 

25,900 

133,000

95,300 

25,400 

15,400 

8,650 

4,110 

2,010

1,490 

35,000

50,500 

28,800 

13,200

9,030 

8,710

3,830 

1.310 

5,000 

79,600 

55,300

23,500

12,100 

10,300 

9,550

3,840 

5,170 

179,00

117,000

94,300 

80,300 

70,500 

306,000 

92,100

47,800 

23,000 

12,200
TABLE 21. Velocity and suspended-sediment concentration of water in the Colorado River 

to July ^4, 1935

Type of measurement: K, Regular; V, velocity observations taken just before and just after collection of silt samp

Sampling points: Samples were taken at points A to D at distances of 120,180, 240, and 300 feet, respectively, from 

Type of sample: I, Integrated; S, surface.

Date

1935

Apr. 8... -----------

Apr. 14--..-... 

Apr. 17. . -

Apr. 20.--.. -------

Apr. 21-. -

Apr. 28.-- ~

May8 -------

May 12 -------- 

May 15 ---------

May 19 - . 

May22 .. -

Time

9:45 a. m__ _______ .

9:45 a. m. ____ . ___ -

9:15 a. m.. ___ --------

4:25 p. m __ __ 

9:00 a. m... ___ ._ 

9:20 a. m-. _-- _-

4:05 p. m _____ __ __ 

10:00 a. m--.-^._-------

12:00n. .. .. 

5:00 p. m _________ 

9:00 a. m._ _____ .....

9:05 a. m.. .......... 

9:20 a. m. ________ 

9:00 a. m_ ________

Gage 

height 

(feet)

6.11 

7.28

6.98 

6.38

7.94 

8.28

8.04 

9.46

8.19 

9.80 

8.17

7.96 

8.01

9.96 

10.15

11.55

12.56 

12.53

Type of 

measurement

R 

R

R 

V

R 

V

V 

V

V 

V 

V

R 

V

R 

V

V

R 

R

Observati

Mean velocity (ft. /sec.) ,

A

3.90 

4.97

4.74 

4.30

5.07 

5.26

5.46 

5.72

5.38 

5.71 

5.09

5.18 

5.25

5.39 

6.59

6.03

6.54 

6.42

B

5.11 

6.10

6.93 

6.18

6.92 

6.57

7.34

7.58

6.88 

7.28 

6.80

6.28 

6.35

7.55 

7.90

8.75

7.69 

8.91

C

4.99 

5.44

4.94 

5.95

5.94 

6.57

5.98 

7.20

5.48 

6.78 

6.25

5.81 

5.91

6.40 

6.94

7.75

7.65 

8.76

D

4.48 

5.68

5.77 

4.44

5.33 

5.26

5.44 

5.82

5.54 

5.92 

5.31

5.27 

5.23

6.48 

6.65

6.30

6.26 

6.35

A

12.0

14.6 

14.6

15.3 

16.0

14.8 

15.6

16.0 

16.7 

15.6

15.8 

15.8

17.7 

16.8

18.6

21.5 

20.6
July 6-. ._ _ __

July 11. ............ 

July 13. ............

July 17.. ........ ... 

July 20. ............

July 24.............

Q»en o m

4:00 p. m- _ .. ____ ...

4:10 p. m.... ____ ....

11:25 a. m.- 

9:35 a. m. ___ ____ ..

12.30

15.07

15.38

17.82

19.02

19.20

OQ OQ

23.00

21.44

21.07

19.44

19.08

15.35

12.93 

12.24

11.50 

10.43

9.97

V

R

V

V

R

V

R

V

R

V

R

V

V

V 

V

V

V

V

7.17

7.48

6.81

7.26

7.01

7.92

8.45

7.84

7.79

6.62

6.95

5.12

4.06 

3.91

3.70 

3.30

3.40

8.18

9.73

9.93

9.76

9.04

8.96

9.81

9.74

8.84

8.00

8.27

5.80

5.07 

4.98

,.4.08 

3.94

3.70

7.74

8.60

9.16

10.07

9.22

9.31

10.04

9.75

9.16

9.20

8.15

8.32

5.80

5.23 

5.08

4.74 

3.80

3.63

6.16

7.02

6.88

6.26

8.19

8.02

9.40

9.09

8.07

7.84

7.47

7.61

5.36

4.94 

4.23

4.16 

3.64

3.32

20.4

24.2

24.0

27.0

28.5

27.6

31.8

30.4

28.4

24.1

21.4 

20.7

20.2 

19.1

18.7
TABLE 22. Velocity and suspended-sediment concentration of water in the Colorado River a

29, 1935

Type of measurement: R, Regular.

Sampling points: Samples were taken at points A to D at distances of 70, 200, 300, and 450 feet, respectively, from ze

Type of sample: I, Integrated, S, surface.

Date

19S5

Apr. 3. . ... ...

Apr. 6-.. ...........

Apr. 10 

Apr. 13 -

Apr. 17 

Apr. 20 ........

Apr. 24 .... ......

Apr. 27... ... .......

May 1 ___

May 4 ____ .....

May8. ______

JVLfly 15-------------

May 18... ....... ...

May 22........ .... .

May 25 _____ ...

Time

10:00 a. m. _______

12:15 p. m ______ ...

11*15 a m

12:25 p. m ....... .....

11:05 a.m. 

9:50 a.m. ______ ...

11:30 a. m..- 

1:25 p.m...... . -

9:35 a.m... .............

10:05 a.m.. ____ .....

3;45 p. m- ... ..... ...

10:25 a. m. ..............

10:45 a.m. ..............

10:00 a.m. ___ .......

10:00 a.m.. __ ........

Gage 

height 

(feet)

12V 22

12.23

12.24

12.23

12.11

12.15

12.32

12.37

12.30

12.20

12.29

12.27

12.24

12.21

' 13.41

Type of 

measurement

R

R

R

R

R

R

R

R

R

R

R

R

R

R

R

Observation

Mean velocity (ft./sec.)

A

3.71

4.16

3.37

3.58

3.62

3.44

3.52

3.46

4.06

3.96

3.18

3.73

3.49

2.98

4.52

B

5.00

5.34

5.22

5.40

5.15

5.13

5.31

4.80

4.99

5.06

4.74

4.36

4.40

4.54

6.20

C

4.87

4.81

5.10

5.16

4.87

4.90

5.15

4.44

4.69

4.78

4.59

4.82

4.40

4.44

6.56

D

2.31

3.10

3.08

3.96

3.85

2.80

3.39

3.40

3.15

3.10

3.33

3.32

3.88

4.26

4.72

D

A

15.5

13.5

14.9

13.8

13.0

14.6

13.0

14.8

15.6

13.5

14.9

ft n o. u

9.0

10.9

10.0
June 1 _______

June 12 .............

June 26. ............

June 29. ____ ....

9:60 a. m... ...

11:00 a.m...... _ .. _ .

9:45 a. m. .............

14.25 

14.38

14.38

14.62

14.68

14.57

13.85 

13.57

B 

R

R

R

R

R

R 

R

4.40 

4 60

5.08

4.36

4 80

4.93

4.36 

4.32

5.72 

5.82

6.79

6.00

R on

5.60

5.30 

5.70

6.12 

5.64

5.74

5.92

5.90

6.28

5.46 

6.77

5.10 

5.30

4.52

4 47

4. do

4.02

4.12 

4.35

14.2 

13.0

14.3

16.5

17.3

17,4

16.8 

16.6
150 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 23. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Grand Canyon, Ariz., Apr. 5, 1935, to 

Sept. 30, 1941

Date of collection

1935

Apr. 12......... .... ...

Apr. 16... ... ... ... .

Apr. 19.. .

Apr. 20...... .............

Apr. 23........ ...........

Apr. 26-... 

Apr. 27..- 

Apr. 28-... 

May5 .... 

May?. 

May 11---.........--..--.

May 16.---. ..............

May 17 . 

May 21. ... ... 

May22... .-. .

May 23, 4:35 p. m -

May 24 ...... ...... - 

May 26. -------

May 27. ---------------

June 20, 3:55 p. m ___ _

June 22.. __________

June 29. ....... ......

Mean 

daily discharge 

(sec.-ft.)

9,330 

11,600 

14,400 

10,200 

12,300 

13,500 

14,400 

14,000 

15,800 

16,900 

15,200 

14,000

| 15,600

16,700 

17,400 

16,400 

15,300 

14,100 

13,400 

13, 100 

14,300 

16,200 

18,500 

20,900 

24,100 

23,300 

25,200 

26,300

| 29,700

31,000 

26,800 

26,000 

27,300

} 31,100

} 36,200 

40,000 

j 44,500

48,600 

49,400 

46,200 

47,100 

50,700

| 54,200

57,800 

63,600 

69,800 

72,600 

84,300 

86,400 

87,200 

91,900 

101,400 

103,100

| 89,000

j 80,900

77,000 

70,300 

65,400

} 58,800 

53. 700

Suspended sediment

Mean 

daily concentration (percent)

1.31 

1.42 

2.16 

.89 

1.11 

.46 

.23 

.06 

.26 

.40 

.08 

.92

1.04

1.22 

1.28 

1.04 

.99 

1.06 

.73 

.68 

.77 

.80 

.98 

1.13 

1.45 

1.36 

1.26 

1.22

1.38

1.48 

1.48 

1.08 

1.01

1.01

1.26 

* 1.38 

1.54

1.90 

1.58 

1.31 

1.08 

1.10

1.28

1.28 

1.25 

1.26 

1.14 

1.22 

1.06 

1.09 

1.03 

1.01 

.82

.79

.72

.55 

.56 

.44

.44 

.37

Tons per 

day

330,000 

445, 000 

840,000 

245,000 

369,000 

532,000 

478,000 

401,000 

538,000 

639,000 

443,000 

348,000

438,000

550,000 

601,000 

461,000 

409,000 

404,000 

264,000 

241,000 

297,000 

350,000 

490, 000 

638,000 

944,000 

856,000 

857,000 

866,000

1,110,000

1, 240, 000 

1, 070, 000 

758,000 

744,000

848,000

1, 230, 000 

1,490,000 

1, 850, 000

2,490,000 

2,110,000 

1,630,000 

1, 370, 000 

1,510,000

1, 870, 000

2,000,000 

2, 150, 000 

2,370,000 

2,230,000 

2,780,000 

2,470,000 

2, 570, 000 

2,560,000 

2, 770, 000 

2,280,000

1,900,000

1, 570, 000

1, 140, 000 

1,060,000 

777,000

699,000 

537.000

Percent in indicated size range

< 0.005 

mm.

26.5 

23.6 

21.2 

27.8 

19.7 

20.1 

19.7 

16.2 

13.8 

9.7 

10.9 

12.1

f 8.6 

( 9.1 

5.4 

8.2 

10.8 

12.8 

22.5 

29.1 

13.8 

9.7 

11.6 

5.9 

4.2 

6.3 

9.5 

7.5 

14.6 

f 11.0 

\11.4 

20.4 

25.2 

25.0 

12.5 

f 10.5 

X 15.1 

f 14.1 

X 14.7 

16.1 

f 13.1 

( 4.6

14.1 

16.1

8.4 

8.8 

10.3 

f 2.9 

X 7.9 

9.5 

7.2 

10.3 

5.9 

7.5 

6.3 

10.2 

14.7 

9.5 

12.5 

f 13.5 

X 15.3 

f 7.7 

\ 12.7 

9.8 

10.7 

9.5 

f 7.4 

X 8.3 

11.9

0.005- 

0.020 

mm.

16.1 

17.7 

13.5 

17.1 

17.1 

14.9 

19.0 

16.4 

11.3 

13.4 

14.5 

14.9

9.8 

15.3 

7.6 

6.9 

8.8 

12.6 

19.5 

19.5 

20.0 

11.1 

15.7 

9.2 

5.6 

7.1 

10.9 

11.7 

13.8 

7.2 

9.5 

14.9 

16.1 

17.9 

10.7 

11.6 

8.6 

9.9 

15.0 

15.9 

13.5 

4.5

12.0 

14.1 

10.4 

8.7 

9.9 

5.3 

9.6 

11.1 

9.0 

12.0 

7.9 

7.8 

7.8 

13.6 

15.7 

10.8 

12.4 

10.1 

16.0 

9.2 

11.2 

8.9 

10.5 

11.6 

8.0 

8.6 

14.6

0.020- 

0.050 

mm.

15.7 

17.0 

13.6 

25.4 

14.7 

15.8 

17.5 

13.4 

15.5 

17.1 

15.7 

13.8

10.4 

12.6 

7.6 

7.6 

8.7 

8,7 

11.2 

9.9 

12.6 

11.3 

14.5 

9.1 

7.2 

10.6 

11.3 

10.6 

12.0 

8.2 

7.2 

11.6 

10.0 

12.4 

12.1 

7.6 

11.7 

14.2 

14.4 

14.0 

9.5 

3.4

9.5 

10.4 

7.8 

8.4 

11.7 

4.9 

8.4 

9.9 

8.2 

13.8 

9.0 

12.8 

10.5 

13.0 

21.8 

14.1 

17.0 

12.3 

20.5 

11.6 

15.7 

14.5 

15.1 

14.1 

11.8 

13.4 

17.8

0.050- 

0.074 

mm.

12.1 

9.1 

" 12.8 

4.0 

15.3 

16.4 

15.8 

15.3 

12.2 

17.0 

13.5 

20.4

11.5 

9.8 

35.6 

8.4 

7.7 

11.5 

12.6 

15.0 

13.7 

15.6 

18.6 

10.9 

10.6 

12.6 

13.6 

11.5 

13.4 

10.3 

12.7 

11.2 

10.3 

8.6 

11.7 

9.1 

10.9 

13.1 

15.1 

10.6 

10.1 

5.2

8.3 

8.4 

7.9 

8.4 

10.3 

7.3 

7.2 

11.0 

6.7 

13.3 

9.3 

7.8 

8.9 

10.7 

15.6 

10.2 

12.5 

13.0 

9.9 

11.2 

16.5 

17.0 

12.5 

11.3 

9.5 

13.3 

13.4

0.074- 

0.149 

mm.

18.8 

21.7 

19.3 

15.1 

24.6 

27.8 

21.9 

26.8 

34.8 

31.0 

34.7 

25.4

36.6 

30.0 

22.9 

26.0 

28.0 

31.1 

22.5 

22.1 

32.9 

39.9 

29.6 

31 9 

33! 7 

38.1 

45.0 

47.4 

37.9 

47.4 

39.2 

32.7 

26.2 

27.9 

33.1 

38.0 

35.2 

32.5 

23.2 

33.8 

30.3 

29.5

35.7 

32.0 

24.3 

35.3 

37.7 

29.0 

25.7 

36.3 

31.9 

31.9 

34.1 

35.0 

40.6 

33.2 

27.5 

26.4 

30.3 

31.6 

28.1 

30.7 

30.3 

28.8 

37.7 

32.5 

42.1 

34.8 

25.2

> 0.149 

mm.

10.8 

10.9 

19.6 

10.6 

8.6 

5.0 

6.1 

11.9 

12.4 

11.8 

10.7 

13.4

23.1 

23.2 

20.9 

42.9 

36.0 

23.3 

11.7 

4.4 

7.0 

12.4 

10.0 

33.0 

38.7 

25.3 

9.7 

11.3 

8.3 

15.9 

20.0 

9.2 

12.2 

8.2 

19.9 

23.2 

18.5 

16.2 

17.6 

9.6 

23.5 

52.8

20.4 

19.0 

41.2 

30.4 

20.1 

50.6 

41.2 

22.2 

37.0 

18.7 

33.8 

29.1 

25.9 

19.3 

4.7 

29.0 

15.3 

19.5 

10.2 

29.6 

13.6 

21.0 

13.5 

21.0 

21.2 

21.6 

17.1
QUANTITIES OF SUSPENDED SEDIMENT 151

TABLE 23. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Grand Canyon, Ariz., Apr. 5, 1985, to 

Sept. 30, 1941 Continued

Date of collection

1935 

July 1 ..... ... .......

July 2 ..................

Tnlv 4

July 6 .. 

JulyS 

July 24..... ...........

July 28 -. 

July 31. ................

Aug. 3 .

Aug. 6 ... ... ... .

Aug. 10 

Alltr Id

Ancr 17

Aug. 23,... ............

Aug. 25. .............

Aug. 26 -

Aug. 28 -

Aug. 31 

Sept. 7 ... ... ..

Sept. 11........ ...........

Sept. 14......... ..........

Sept. 21...................

Sept. 25 

Sept. 27 

Sept. 30, 8:50 a. m... ......

Oct. I......... ........

Oct. 6 

Oct. 9... ... ... ......

Oct. 12....................

Oct. 16 

Oct. 19 

Oct. 24 ........ .........

Oct. 27 . ---------

Nov. 2......-: . ........

Nov. 7 . ..

Nov. 10- ----------

Nov. 13 ....... .... ..

Nov. 16. --------------

Nov. 20-------- _ -------

Nov. 23 

Nov. 27 ---------

Nov. 30- ---------

Dec. 4-. __ _ __ .-.___--.

Dec. 11-. --------------

Dee. 14.. .............. --_

Dec. 17... ---------

Dec. 21....... -. ........ ._

Dec. 25...-- .... . -..-_

Dec. 29.. -------------

1936 

Jan. 1. --- 

Jan. 8 

Jan. 11 

Jan. 15 .

Jan. 18 

Jan. 22. ....... ........

Jan. 24... . .

Jan 29 .......... ......

Mean 

daily discharge 

(sec.-ft.)

47,600 

43,800 

39,200 

35,000 

31,800 

17,100 

14, 100 

11,400

10,600 

12,700 

9,950 

8,720 

9,680 

7,600 

7,380 

9,640 

10,600 

8,240

12,300 

7,670 

6,270 

6,490 

6,370 

5,480 

4,360 

7,420

} 18, 100

15,800 

7,490 

6,550 

5,820 

5,010 

4,660 

5,440 

5,100

5,230 

5,360 

5,680 

5,560 

6,020 

6, 610 

5,790 

5,900 

5,650

5,820 

6,230 

4,970 

5,010 

4,790 

4,600 

3,280 

3,560

3,750 

4,310 

4,220 

4,310 

4,400 

5,040 

5,040 

4,780 

4.670

Suspended sediment

Mean 

daily concentration (percent)

0.36 

.35 

.28 

.30 

.23 

.35 

.46 

.19

.17 

1.82 

.46 

1.11 

.76 

.48 

.52 

4.81 

2.74 

2.14

5.02 

2.00 

.72 

.65 

.33 

.21 

.12 

.24

4.14

5.09 

.88 

.45 

.26 

.14 

.11 

.12 

.16

.20 

.12 

.12 

.12 

.11 

.09 

.09 

.10 

.15

.10 

.22 

.08 

.10 

.09 

.08 

.05 

.07

.08 

.06 

.07 

.05 

.06 

.06 

.07 

.05 

.06

Tons per 

day

463,000 

414, 000 

296,000 

284,000 

197,000 

162,000 

175,000 

58,500

48, 700 

624, 000 

124, 000 

261, 000 

199,000 

98,500 

104,000 

1,250,000 

784,000 

476,000

1, 670, 000 

414, 000 

122, 000 

114, 000 

56,800 

31,100 

14,100 

48,100

2, 020, 000

2, 170, 000 

178, 000 

79,600 

40,900 

18,900 

13,800 

17,600 

22,000

28,200 

17,400 

18,400 

18, 000 

17,900 

13,600 

14,100 

15,900 

22,900

15, 700 

37,000 

10, 700 

13,500 

11,600 

9,940 

4,430 

6,730

8,100 

6,980 

7,980 

5,820 

7,130 

8,160 

9,530 

6,450 

7.570

Percent in indicated size range

< 0.005 

mm.

9.7 

8.9 

10.3 

7.9 

11.0 

36.9 

52.4 

43.5

45.0 

65.0 

59.9 

70.9 

63.9 

62.3 

56.5 

49.3 

63.4 

64:5

53.0 

67.5 

22.4 

60.0 

36.4 

44.3 

61.1 

67.5 

/ 69.2 

\ 55.2

60.3 

47.0 

60.3 

56.5 

54.2 

51.2 

50.6 

55.4

'4.5 

10.9 

10.1 

15.4 

48.2 

13.9 

18.7 

24.8 

9.2

19.3 

4.2 

15.3 

17.4 

24.5 

21.6 

50.1 

17.8

28.7 

39.8 

36.0 

45.7 

37.4 

30.8 

28.3 29.9' 

31.7

0.005- 

0.020 

mm.

10.7 

10.8 

12.2 

7.4 

10.3 

33.7 

34.6 

35.7

37.2 

21.3 

30.0 

23.0 

27.1 

31.1 

32.4 

25.7 

21.4 

27.1

22.9 

23.8 

24.9 

29.6 

19.1 

27.5 

27.8 

26.6 

25.4 

34.2

29.5 

43.9 

31.4 

34.6 

33.2 

38.9 

41.4 

32.7

86.3 

72.6 

70.7 

64.6 

30.0 

66.0 

59.7 

54.2 

77.7

61.1 

71.3 

 69.1 

60.9 

58.5 

62.2 

35.2 

67.5

56.5 

42.3 

44.8 

35.8 

41.0 

40.2 

48.7 

55.4 

47.2

0.020- 

0.050 

mm.

15.3 

13.1 

15.2 

13.1 

15.6 

11.7 

7.9 

10.7

11.2 

7.1

4.7 

4.3 

6.8 

4.6 

5.5 

18.5 

9.9 

6.4

17.0 

6.0 

25.9 

8.3 

14.3 

17.9 

7.7 

4.2 

3.9 

6.6

5.9 

5.5 

5.8 

6.1 

9.7 

5.9 

5.5 

10.4

6.8 

11.3 

13.1 

14.0 

17.2 

13.7 

14.4 

14.1 

8.9

14.0 

16.8 

10.3 

11.4 

12.6 

10.5 

9:8 

9.2

9.8 

12.4 

13.6 

13.2 

16.0 

22.3 

17.6 

10.2 

13.8

0.050- 

0.074 

jrnn.

13.1 

11.4 

14.2 

13.1 

15.3 

6.3 

1.6 

3.2

2.1 

2.4 

1.8 

.5 

.8 

.5 

1.6 

3.9 

2.9 

.7

3.8 

1.0 

14.6 

1.0 

5.7 

4.4 

1.1 

.7 

.5 

1.7

1.4 

1.3 

1.1 

1.1 

1.0 

1.5 

.8 

.9

1.1 

2.6 

2.7 

3.0 

3.4 

3.0 

3.3 

3.8 

2.2

2.8 

4.3 

2.8 

6.5 

3.1 

3.5 

2.8 

2.5

2.6 

2.2 

2.9 

2.8 

2.5 

3.4 

5.2 

1.7 

2.8

0.074- 

0.149 

mm.

31.9 

32.8 

30.4 

42.5 

31.3 

7.9 

2.1 

4.6

3.1 

3.3 

3.1

.7 

.8 

.9 

2.8 

2.0 

1.9 

.7

2.7 

1.2 

11.1 

.8 

22.5 

5.0 

1.5 

.8 

.5 

1.6

1.5 

1.4 

.8 

1.3 

1.2 

1.6 

1.1 

.3

.7 

1.6 

2.3 

2.0 

.8 

1.9 

2.9 

1.2 

1.4

1.9 

1.8 

1.4 

1.0 

.9 

1.1 

1.0 

2.1

1.3 

1.8 

1.7 

1.2 

2.1 

2.0 

3.4 

1.3 

2.6

> 0.149 

mm.

19.3 

23.0 

17.7 

16.0 

16.5 

3.5 

1.4 

2.3

1.4 

.9 

.5 

.6 

.6 

.6 

1.2 

.6 

.5 

.6

.6 

.5 

1.1 

.3 

2.0 

.9 

.8 

.2 

.5 

.7

1.4 

.9 

.6 

.4 

.7 

.9 

.6 

.3

.6 

1.0 

1.1 

1.0 

.5 

1.5 

1.0 

1.7 

.7

.9 

1.6 

1.0 

2.8 

.4 

1.1 

1.0 

.9

1.0 

1.5 

1.0 

1.3 

1.0 

1.3 

1.5 

1.5 

1.9
152 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 23. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Grand Canyon, Ariz., Apr. 5, 1936, to 

Sept. SO, 1941 Continued

Date of collection

1936 

Feb. l._ ... ..... _

Feb. 5. .. 

Feb. 8_.-_. _________ ...

Feb. 12.. ................ .

Feb. 15...................

Feb. 19.. .................

Feb. 22...................

Feb. 26......... .

Feb. 29...................

Mar. 4 ... 

Mar. 7- ... .- _ 

Mar. 11 . . ....

Mar. 14...................

Mar. 18...................

Mar. 22...................

Mar. 25 .

Mar. 28... ................

Apr. 1. ...................

Apr. 11..... ...........

Apr. 15... .............

Apr. IS...................

Apr. 22...................

Apr. 25........... .-..

Apr. 29...................

"Wav fi

May 13. ...............

May 21.......... ........

Mav 24

May 27... ........ ..... ...

May 30. ... ... .... .....

June 12...... __ .... .....

July 2......... ........... .

July 4...... .............. .

JulyS.....................

July 11 ... . _ ..........

July 13....... .............

July 14....... .............

July 17 ................

July 18. ................

July 22.... .................

July 25 .___.._.____:__

July 29...... ..............

Aug. 1.. ...............

Aug. 6.. . ..............

Aug. 7 ................

Aug. 10 ...............

Aug. 12-... ...............

Aug. 15 _, _

Aug. 18 ...............

Aug. 24.. .... ....... ..

Aue. 29. ...............

Mean 

daily discharge 

(sec.-ft.)

5,390 

5,680 

4,910 

4,650 

4,970 

6,610 

6,480 

6,730 

7,780

6,970 

8,770 

8,270 

9,140 

9,250 

8,630 

8,470 

7,860

6,740 

7,840 

7,820 

6,720 

11,500 

21,600 

35,400 

43,100 

61,100

51,100 

45,900 

66,400 

46,200 

44,000 

71,800 

75,100 

66,100 

65,400

64,900 

60,300 

60,000 

47,200 

45,900 

40,900 

34,800 

30,100

24,100 

22,400 

16,600 

15,500 

29,800 

29,200 

16,900 

16,300 

15,200 

12,900 

11,400

9,800 

15,300 

29,700 

27,200 

21,000 

15,200 

12,800 

14,900 

9.010

Suspended sediment

Mean 

daily concentra- 

;ion (percent)

0.08 

.17 

.17 

.10 

.07 

.16 

.16 

.32 

.35

.30 

.42 

1.10 

.77 

.62 

.45 

.34 

.37

.35 

.44 

.38 

.26 

1.09 

1.68 

1.57 

1.43 

1.32

1.01 

.67 

1.06 

.64 

.44 

.69 

.58 

.64 

.60

.64 

.60 

.40 

.38 

.33 

.30 

.28 

.19

.17 

.16 

.12 

.12 

.82 

4.72 

3.62 

2.40 

.91 

.74 

1.24

1.13 

3.14 

5.35 

3.99 

2.73 

2.22 

1.15 

2.13 

.98

Tons per

day 

11,600 

25,600 

22,500 

12,600 

9,390 

28,100 

28,000 

68,100 

73,500

48,400 

99,500 

246.000 

190,000 

155,000 

105,000 

77,800 

78,400

63,700 

93,100 

80,200 

47,200 

338,000 

980,000 

1,500,000 

1,660,000 

1,820,000

1,390,000 

830,000 

1,900,000 

674,000 

623,000 

1,140,000 

1, 180, 000 

964,000 

883,000

946,000 

814,000 

540,000 

484,000 

409,000 

331,000 

263,000 

154,000

111,000 

96,800 

53,800 

60,200 

660,000 

3,720,000 

1,650,000 

1,060,000 

373,000 

258,000 

382,000

299,000 

1, 300, 000 

4,290,000 

2,930,000 

1,550,000 

911,000 

397,000' 

857,000 

238.000

Percent in indicated size range

< 0.005 

mm.

36.8 

14.6 

11.6 

15.0 

27.6 

8.3 

4.6 

43.0 

6.6

2.4 

1.8 

56.4 

1.1 

4.6 

3.3 

6.6 

6.3

3.4 

2.7 

4.1 

6.3 

1.1 

18.6 

31.0 

"12.0 

14.4

12.8 

12.1 

6.8 

10.7 

11.3 

8.7 

10.4 

6.1 

4.6

5.4 

7.8 

8.6 

8.6 

6.5 

6.9 

6.3 

9.2

17.3 

21.1 

19.2 

22.5 

21.3 

5.4 

17.8 

28.6 

50.4 

32.9 

26.0

45.7 

39.7 

11.3 

26.6 

9.1 

23.6 

51.5 

8.1 

29.1

0.005- 

0.020 

mm.

32.0 

68.3 

70.8 

47.6 

47.8 

63.2 

69.3 

29.3 

66.6

85.6 

59.6 

28.3 

74.6 

61.6 

76.7 

64.1 

66.1

74.5 

79.6 

67.4 

62.8 

21.9 

15.1 

24.1 

10.9 

13.1

11.0 

10.1 

6.4 

10.9 

10.4 

9.0 

10.7 

5.5 

4.1

4.7 

6.6 

7.4 

8.0 

5.5 

6.6 

6.3 

9.5

14.0 

17.9 

28.6 

32.3 

19.7 

59.9 

66.6 

65.1 

29.9 

43.1 

53.1

43.4 

26.1 

40.2 

36.3 

63.6 

49.9 

27.9 

60.9 

66.7

0.020- 

0.050 

mm.

22.6 

19.7 

13.0 

25.8 

17.2 

24.6 

17.1 

19.6 

18.4

8.0 

21.6 

9.5 

13.1 

15.3 

12.0 

11.8 

13.0

11.4 

11.3 

12.0 

14.3 

9.3 

20.3 

17.1 

13.2 

13.6

12.7 

12.2 

8.1 

12.9 

13.2 

12.5 

12.3 

7.7 

7.3

8.5 

9.0 

9.3 

9.1 

8.4 

9.8 

11.5 

16.6

18.3 

16.2 

15.9 

19.2 

29.6 

17.1 

10.7 

10.8 

14.8 

15.6 

13.7

8.6 

21.6 

16.3 

14.2 

12.6 

15.3 

10.1 

14.3 

7.8

0.050- 

0.074 

mm.

5.4 

4.4 

2.6 

9.0 

4.3 

8.3 

6.3 

4.3 

5.7

2.4 

13.0 

3.4 

7.6 

12.2 

6.6 

9.2 

9.0

7.1 

4.7 

10.0 

11.2 

11.2 

24.2 

20.0 

16.4 

13.8

12.1 

13.3 

12.0 

13.6 

18.7 

16.5 

16.3 

13.9 

12.1

13.5 

13.9 

12.1 

9.1 

12.6 

16.0 

12.5 

19.1

18.7 

12.6 

12.9 

12.5 

16.6 

9.3 

2.7 

2.9 

3.1 

6.1 

5.4

1.6 

10.0 

14.1 

10.8 

6.3 

6.7 

5.0 

9.9 

2.8

0.074- 

0.149 

mm.

1.8 

2.0 

1.0 

1.7 

2.1 

3.8 

2.5 

2.9 

2.9

1.0 

3.2 

1.9 

3.1 

4.4 

1.9 

5.5 

4.7

2.5 

1.4 

5.3 

4.5 

36.0 

18.9 

6.8 

35.5 

33.5

37.1 

35.4 

36.6 

30.5 

24.1 

33.0 

33.1 

33.4 

37.6

32.2 

30.5 

31.0 

42.7 

28.0 

35.7 

43.3 

31.7

21.4 

22.4 

13.7 

8.5 

7.7 

5.9 

1.3 

2.0 

1.4 

1.6 

1.3

0.7 

2.0 

16.0 

10.1 

6.4 

3.6 

4.3 

5.9 

2.6

> 0.149 

mm.

1.4 

1.0 

1.0 

.9 

1.0 

1.8 

1.2 

.9 

.8

.6 

.8 

.4 

.5 

1.8 

1.0 

2.7 

.9

1.0 

.3 

1.2 

.8 

20.5 

2.8 

1.0 

11.9 

11.6

14.4 

16.9 

30.1 

21.3 

22.3 

21.2 

17.2 

33.4 

34. a

, 35.7 

32.2 

31.6 

22.5 

39.0 

25.0 

20.1 

14.0

10. a

9.8 

9.6 

4.7 

5.1 

2.4 

.9 

.6 

.4 

.7 

.5

0.3 

.6 

2.2 

1.9 

2.0 

.9 

1.1 

.8 

.9
QUANTITIES OF SUSPENDED SEDIMENT 153

TABLE 23. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Grand Canyon, Ariz., Apr. 5, 1935, to 

Sept. SO, 1941 Continued

Date of collection

19S6

Sept. 9- ____ . .........

Sept. 12 

Sept. 16- ... ...

Sept. 19......... ... . 

Sept. 26- 

Oct. 2 ..... _v . 

Oct. 8 ... ...... .... .

Oct. 10 ....... ... ... .

Oct. 13 

Oct. 17 

Oct. 21 

Oct. 24 . 

Oct. 28 ..... ... 

Oct. 31 

Nov. 4 __________ ..

Nov. 7 ... .... .. ...

Nov. 10 

Nov. 14 

Nov. 17... __ . __ 

Nov. 21 

Nov. 24. ____ ....... ...

Nov. 28.. .. ....... .

Dec. 1..... _ ...... 

Dec. 5... .... ....

Dec. 12........ ........

Dec. 15.. 

Dec. 22.. .................

Dec. 26.. ..... ... . .....

Dec. 29......... ..........

1937

Jan. 2, 5, 9, 12, 16, 19, 23, 

27,30... .

Feb. 2, 6 

Feb. 9....................

Feb. 10.. 

Feb. 13.. .................

Feb. 16......... .......

Feb. 17......, .........

Feb. 20....... .........

Feb. 23....... ............

Feb. 27... ...... ... ,.

Mar. 2, 6, 9.. .............

Mar. 13...... ..........

Mar. 16 ..............

Mar. 20. __ . ......

Mar. 23 ............

Mar. 27 ______ ....

Mar. 30. _ ... _____ ..

Apr. 3.......... ..........

Apr. 10-.. ..........

Apr. 13.......... .........

Apr. 17, 19, 21-22, 25-26... 

Apr. 27...................

Apr. 28-30.. .... ___ ....

Mean 

daily discharge 

(sec. -ft.)

21,500 

14,900 

10,800 

8,830 

8,600 

7,870 

8,220 

7, 870 

5,280

5,300 

5,580 

5,520 

5,740 

5,650 

5,870 

6,520 

6,980. 

6,830

9,670 

8,710 

7,570 

7,510 

7,120 

7,070 

7,180 

6,990

6,600 

5,960 

5,560 

4,880 

4,210 

4,580 

5,700 

6,020 

6,410

13,660

14,850 

17,100' 10,000 

8,720 

8,930 

18,200 

13,400 

9,890 

7,890

18,200 

10,800 

14,600 

22,000 

20,100 

16,300 

13,100

10,800 

15,300 

15, 000 

19,200 

140,400 

36.500 

1 32. 600

Suspended sediment

Mean 

daily concentra- 

;ion (percent)

7.74 

3.43 

2.40 

1.38 

1.49 

.80 

2.08 

1.35 

.91

.50 

.31 

.26 

.24 

.21 

.24 

.55 

.49 

.40

1.91 

.95 

.69 

.36 

.33 

.19 

.20 

.16

.13 

.16 

.11 

.11 

.08 

.08 

.08 

.12 

.11

1.06

1.07 

.46 

4.32 

.95 

.44 

2.34 

1.88 

1.03 

.45

1.49 

.95 

1.75 

2.87 

2.26 

1.53 

.99

.62 

1.45 

1.18 

1.80 

12.34 

1.65 

i 1.40

Tons per 

day

4,490,000 i,38o;ooo

700, 000 

329,000 

346,000 

170,000 

462,000 

287,000 

130,000

71,600 

46,700 

38,800 

37,200 

32,000 

38,000 

96,800 

92,300 

73,800

499,000 

223,000 

141,000 

73,000 

63.400 

36,300 

38,800 

30,200

23,200 

25,700 

16,500 

14,500 

9,090 

9,890 

12,300 

19,500 

19,000

i 6, 690

19,220 

124,000 

1,990,000 

224,000 

106,000 

1, 150, 000 

680,000 

275,000 

95,900

1 109,000 

277,000 

690,000 

1, 700, 000 

1,230,000 

673,000 

350,000

181,000 

599,000 

 478, 000 

933,000 

i 2, 560, 000 

1,630,000 

1 1. 230. 000

Percent in indicated size range

X

< 0.005 

mm,

4.7 

4.2 

5.6 

11.6 

8.7 

12.7 

5.7 

9.4 

10.2

6.4 

7.9 

8.4 

14.3 

5.6 

3.6 

5.8 

4.3 

5.7

48.4 

3.1 

3.3 

7.4 

2.6 

4.4 

5.8 

6.5

21.8 

19.5 

19.9 

25.8 

35.7 

28.6 

36.7 

22.1 

21.3

3.6

7.9 

24.2 

20.7 

47.3 

31.6 

21.4 

44.8 

45.0 

48.3

47.8 

42.5 

35.6 

18.9 

19.2 

56.3 

38.2

37.0 

26.2 

32.9 

23.5 

15.8 

15.2 

15.6

0.005- 

0.020 

mm.

51.1 

66.8 

74.9 

74.7 

73.4 

71.5 

67.9 

66.6 

76.7

75.1 

70.6 

56.1 

56.4 

56.6 

41:7 

65.7 

58.8 

61.1

25.6 

67.7 

72.7 

69.6 

47.9 

62.1 

56.1 

53.9

37.6 

31.1 

22.3 

38.2 

28.6 

42.0 

36.6 

28.8 

24.6

39.5

43.2 

47.0 

24.2 

33.0 

42.7 

16.4 

26.4 

36.2 

32.2

25.8 

22.8 

20.7 

33.8 

16.5 

12.0 

15.3.

22.0 

15.8 

15.7 

14.0 

11.8 

11.5 

11.8

0.020- 

0.050 

mm.

15.6 

13.2 

10.0 

8.1 

9.2 

7.8 

13.8 

12.2 

6.6

7.8 

11.1 

12.5 

14.1 

14.4 

17.0

12.8 

11.8

11.1 

11.2 

9.5 

15.0 

15.2 

20.5 

24.4 

23.1

22.3 

19.0 

18.0 

20.3 

17.5 

17.0 

20.0 

26.3 

27.9

48.4

39.3 

6.4 

14.0 

14.3 

17.8 

26.2 

16.2 

12.0 

10.4

14.2 

17.5 

14.7 

11.8 

16.3 

9.4 

13.6

13.9 

14.2 

16.3 

20.0 

18.3 

15.7 

15.7"

0.050- 

0.074 

mm.

13.5 

7.0 

4.5 

3.9 

4.7 

4.4 

7.3 

7.9 

3.6

4.6 

5.7 

l».l 

6.5 

9.7 

19.8

9.2

7.6

6.5 

8.9 

6.0 

5.5 

11.0 

10.2 

11.4 

12.0

11.7 

13.0 

12.2 

7.9 

10.5 

8.1 

4.6 

12.1 

15.4

3.2

5.3 

15.3 

14.6 

3.0 

5.2 

20.8 

8.5 

5.0 

- 6.4

6.9 

12.2 

13.5 

12.9 

16.8 

8.8 

12.2

9.5 

13.8 

15.4 

19.4 

16.1 

15.4 

14.6

0.074- 

0.149 

mm.

12.8 

7.3 

4.3 

.6 

3.4 

2.6 

4.8 

3.2 

2.1

4.6 

3.5 

10.3 

6.8 

10.7 

16.2

12.9 

11.3

7.7 

1.3 

7.1 

1.9 

19.3 

2.4 

1.8 

3.9

4.7 

13.6 

18.2 

6.3 

6.2 

3.3 

1.4 

9.2 

9.1

2.6

2.5 

6.3 

21.6 

1.8 

2.3 

14.0 

3.6 

1.4 

2.2

4.0 

4.1 

11.8 

17.3 

22.0 

10.5 

15.4

13.6 

21.1 

17.0 

14.9 

26.2 

28.1 

25.0

> 0.149 

mm.

2.3 

1.5

.7 

1.1 

.7 

.9 

.5 

.6 

.7

1.5 

1.2 

2.6 

1.9 

3.0 

1.7

2.0 

2.5

.7 

7.8 

1.4 

.6 

4.0 

.4 

.5 

.6

1.9 

3.8 

9.4 

1.5 

1.5 

1.0 

.7 

1.5 

1.7

2.7

1.8 

.8 

4.9 

.6 

.4 

1.2 

.5 

.4 

.5

1.3 

.9 

3.7 

5.3 

9.2 

3.0 

5.3

4.0 

8.9 

2.7 

8.2 

11.8 

14.1 

17.3

1 Mean for days on which size samples were collected.
154 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 23. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Grand Canyon, Ariz., Apr. 5, 1935, to 

Sept. 30, 1941 Continued

Date of collection

. 1937

May 2-3, 5.. 

May 9_____ _- - 

Mayl2 _ 

May 13- -. .............

May 16, 18-20--- - 

May 22-25, 27-30 .- -

June 2-5, 7, 9-10 -

June 11-12, 14, 17 .......

 

July 1 __ . ---

July 2 ........ ..........

July9- .................

July 10-11..... . . .

July 13 .. 

July 14 .................

July 17- ................

July 20, 22_-_. . ...........

July 24, 26-- - .-

July 28- 

JulySl ............ 

Aug. 7-8, 10,12, 15-16-.... 

Aug. 18, 21, 23, 26, 28, 30- -

Sept. 4-6_ _ .__-___-__--__

Sept. 9, 11. ........ _______

Sept. 14.. - -- -

Sept. 17, 19, 23 -----

Sept. 26 _ __ _ _.__ .

Sept. 29 ________________

Sept. 30..... . -.- ---

Oct. 1- __ -

Oct. 4... __________________

Oct. 7 -. _______________

Oct. 10 ... --... _.

Oct. 13 

Oct. 16, 19.. .-_._______-_.

Oct. 22, 25, 27- -- 

Nov. 2__ ...... ... - 

Nov. 6, 9, 13, 17, 22, 26, 29- 

Dec. 3, 7, 11. .-___.-.______

Dec. 14..-....-...- ..

Dec. 18,23 

Dec. 27..... ... ..

Dec. 31. _ 

1938 

Jan. 4,8, 12, 16 -

Jan. 20-.--. _ -.-_-_. ...

Jan. 24- .-_._.....-__..._

Jan. 28, 31... .- -- 

Mean 

daily discharge 

(sec.-ft.)

36,000 

29,000 

35,700 

43,600 

57,200 

65,400 

i 77, 900 

164,100

i 55, 200 

i 35, 800 

i 32, 100

30, 800 

28,800 

18, 700 

i 19, 000 

27,100 

27,200 

30, 900 

i 25, 000 

i 15, 200 

11,300 

14,500

11, 100 

10, 100 

i 7, 640 

14,580

9,760 

14, 700 

i 13, 900 

i 8, 130 

7,340 

i 4, 970 

4,370 

4,220 

10,400

13,900 

23,100 

10, 500 

5,960 

5,680 

5,350 

i 5, 370 

i 7, 790

7.060 

i 6, 670

i 6, 330 

8,600 

i 7, 800 

5,790 

5,130

i 5, 070 

5,910 

6,700 

i 5, 180

Suspended sediment

Mean 

daily concentration (percent)

1.46 

.89 

1.00 

1.28 

1.56 

1.92 

i 1.21 

 1.82

1.71 

1.44 

1.45

.40 

1.00 

.38 

i 1.19 

2.47 

2.52 

2.73 

i 2.16 

i 1.25 

.71 

1.32

2.14 

1.60 

1.72 

1.27

2.49 

4.77 

12.96 

12.56 

1.41 

1.79 

.91 

.40 

1.13

5.44 

5.38 

7.54 

2.73 

1.08 

.51 

1.26 

1.76

.53 

1.23

M4 

.75 

1.38 

.25 

.14

1.10 

.15 

.23 

1.12

Tons per 

day

1, 420, 000 

701,000 

964,000 

1, 510, 000 

2, 410, 000 

3, 390, 000 

i 2, 540, 000 

i 1,460,000

i 1,080,000 

i 430, 000 

i 390, 000

333, 000 

778, 000 

192, 000 

i 609, 000 

1,810,000 

1, 850, 000 

2, 280, 000 

i 1, 480, 000 

i 520, 000 

217,000 

517, 000

641, 000 

436, 000 

i 150, 000 

i 33, 200

656, 000 

1, 890, 000 

i 1, 110, 000 

i 564, 000 

279, 000 

i 107, 000 

107. 000 

43, 300 

233, 000

2, 040, 000 

3, 360, 000 

2, 140, 000 

439, 000 

166,000 

73, 700 

i 38, 200 

i 159, 000

101, 000 

i 42, 000

i 23, 400 

174, 000 

i 79, 300 

39,100 

19, 400

i 13, 800 

23, 900 

41,600 

17. 000

Percent in indicated size range

< 0.005 

mm.

12.4 

13.8 

7.6 

7.2 

11.3 

9.6 

11.2 

7.1

8.9 

9.4 

12.2

13.8 

36.9 

38.3 

46.8 

43.8 

41.8 

36.3 

40.5 

50.1 

62.1 

51.8

58.1 

61.9 

' 60.0 

76.2

64.5 

48.1 

48.2 

66.1 

62.4 

68.7 

72.1 

60.5 

38.2

29.2 

25.9 

62.2 

77.2 

81.8 

60.5 

54.8 

52.7

47.4 

36.3

33.4

7.7 

27.7 

37.5 

51.4

41.7 

23.2 

28.7 

38.9

0.005- 

0.020 

mm.

10.1 

10.2 

6.8 

6.1 

10.9 

10.1 

11.0 

6.7

6.6 

7.8 

10.7

12.8 

24.5 

23.5 

27.1 

 22.9 

22.9 

22.7 

13.6 

18.9 

20.1 

17.9

29.3

27.7 

29.7 

16.8

23.5 

22.3 

29.3 

23.8 

29.3 

25.7 

21.7 

33.3 

32.1

16.4 

14.4 

12.0 

14.7 

11.5 

 28.3 

30.8 

24.1

32.2 

20.1

20.0 

9.0 

17.0 

34.6 

26.0

23.5 

16.9 

19.3 

22.9

0.020- 

0.050 

mm.

16.3 

14.3 

12.6 

12.1 

19.1 

19.4 

17.4 

13.1

12.7 

13.0 

14.7

12.5 

16.7 

12.0 

15.6 

17.5 

18.4 

13.6 

28.1 

23.6 

14.2 

16.3

9.8 

8.2 

8.8 

5.8

9.0 

17.9 

15.1 

8.1 

6.9 

4.9 

5.6 

5.2 

21.9

16.8 

19.6 

17.1 

6.4 

4.8 

8.7 

11.0 

15.6

12.3 

20.6

23.8 

42.0 

24.4 

12.1 

11.5

16.6 

18.6 

22.6 

18.1

0.050- 

0.074 

mm.

18.5 

18.9 

17.6 

17.1 

15.6 

17.5 

13.6 

13.7

14.4 

15.7 

16.0

23.4 

7.5 

6.8 

4.0 

6.9 

8.1 

8.0 

7.1 

3.0 

1.6 

6.5

1.2 

.9

.7 

.2

.9 

7.5 

3.7 

1.0 

.6 

.2 

.1 

.3 

5.4

10.5 

21.5 

4.1 

.8 

1.0 

1.4 

1.6 

3.4

4.7 

9.9

12.8 

29.0 

18.2 

8.6 

6.0

8.4 

20.2 

15.2 

11.2

0.074- 

0.149 

mm.

30.7 

26.1 

30.6 

32.2 

28.2 

29.9 

28.3 

26.3

28.5 

' 25.7 

24.7

27.0 

8.9 

11.0 

4.9 

5.9 

6.0 

11.9 

7.7 

2.9 

1.4 

5.2

1.1

.9 

.6 

.5

1.5 

3.2 

2.9 

.7 

.6 

.4 

.4 

.5 

2.0

26.2 

17.1 

3.5 

.6 

.7 

.9 

1.3 

3.5

2.6 

8.4

7.1 

11.3 

10.6 

5.2 

3.5

7.9 

15.8 

11.3 

6.6

> 0.149 

mm.

12.0 

16.7 

24.8 

25.3 

14.9 

13.5 

18.5 

33.1

28.9 

28.4 

21.7

10.5 

5.5 

8.4 

1.6 

3.0 

2.8 

7.5 

3.0 

1.5 

.6 

2.3

0.5 

.4 

.2 

.5

.6 

1.0 

.8 

.3 

.2 

.1 

.1 

.2 

.4

.9 

1.5 

1.1 

.3 

.2 

.2 

.5 

.7

.8

4.7

2.9 

1.0 

2.1 

2.0 

1.6

1.9 

5.3 

2.9 

2.3

i Mean for days on which size samples were collected.
QUANTITIES OF SUSPENDED SEDIMENT 155

TABLE 23. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Grand Canyon, Ariz., Apr. 5, 19S5, to 

Sept. 30, 1941 Continued

Date of collection

1938 

Feb. 3,8, 12 __________

Feb. 15 

Feb. 18...-. . ..... 

Feb. 21----___. ___ .___

Feb. 25 

Feb.28.-.- ... ... ....

Mar. 3 

Mar. 5 

Mar. 8 

Mar. 14, 18___---_. _______

Mar. 21, 25, 29--_ .... __

Apr. 6, 9, 13 _-_-_______.

Apr. 16---.- . ------

Apr. 21--. . ... ....

Apr. 22-.- 

May 4-5, 7, 10_. ..____....

May 16-17.--. ..

May 18-19 

May 24, 28, 30-31-... ... 

June 1, 8, 11, 13, 15..__i___

June 18, 21, 23, 25, 29__ _

July 2 _

July 6-6- --------..--.-

July 9, 11, 13, 18,20.......

July 26, 30.. - ...

Aug. 1,6, 9---.-..........

Aug. 10----------. __ . _

Aug. 12- ... ....

Aug. 14-. ..............

'.ug. 17 - 

Aug. 23. ... ....

Aug. 27- - 

Aug. 30 ........ ...

Sept. 2 ..

Sept. 3 

Sept. 5 -_- _

Sept. 12 ..... 

Sept. 17 

Sept. 24, 27..-.- ___.. ..

Oct. 2, 6, 9, 12 -- - .

Oct. 17, 20-.. ..-

Oct. 25. ..

Oct. 28, 31-. . _.

Nov. 4, 8, 11, 14, 17 

Nov. 20, 23, 26, 29 

Dec. 4, 8, 11, 14, 17, 20, 23, 

26, 29s.-- --.---..

Mean 

daily discharge 

(sec.-ft.)

i 5, 880 

7 570 

8,340 

7,420 

6,010 

6,010

11,200 

39, 100 

20, 700 

i 11, 800 

i 12, 200

13,400 

1 10, 200 

17, 900 

23, 400 

36,600 

43,400 

i 59, 200 

57, 400

i 55, 500 

1 32, 300 

i 57, 600 

i 65, 600

1 84, 800 

i 65, 700 

64, 900

60, 200 

i 48, 200 

i 26, 500 

i 13, 300

i 10, 600 

10,200 

9,030 

12,200 

9,680 

9,510 

7,070 

5,570 

5,050

6,230 

8,400 

19,300 

21, 300 

22,500 

19, 600 

i 10, 400 

8,550

i 8, 470 

1 11, 300 

10, 800 

i 9, 520

i 8, 930 

17,600

i 7. 250

Suspended sediment

Mean 

daily con 

centration (percent)

1.16 

.42 

.69 

.45 

.23 

.20

2.91

8.76 

2.88 

11.12

i.77

.90 

1.51 

1.18 

1.72 

2.38 

2.94 

12.69 

2.22

11,30 

1.66 

11.38 

1.96

1.73 

1.53 

.73

.96 

1.44 

1.21 1.16

1.13 

1.24 

.84 

.38 

.81 

1.92 

.64 

.34 

.20

.14 

.62 

3.04 

2.65 

3.01 

2.20 

'.56 

.20

1.22 

1.69 

.48 

1.33

1.14 

1.07

1.06

Tons per 

day

i 25, 500 

85, 800 

155, 000 

90, 200 

37, 300 

32, 500

880, 000 

9, 250, 000 

1, 610, 000 

i 354, 000 

i 256, 000

326, 000 

i 140, 000 

570, 000 

1, 090, 000 

2, 350, 000 

3, 450, 000 

i 4, 300, 000 

3, 440, 000

i 2, 020, 000 

1 592, 000 

i 2, 160, 000 

i 1, 720, 000

i 1, 680, 000 

i 956, 000 

1, 280, 000

1, 560, 000 

i 580, 000 

i 162, 000 

i 60, 200

i 36, 700 

341,000 

205, 000 

125, 000 

212, 000 

493, 000 

122, 000 

51, 100 

27,300

23,500 

141, 000 

1, 580, 000 

1, 520, 000 

1, 830, 000 

1, 160, 000 

i 163, 000 

46, 200

i 57, 200 

i 212, 000 

140,000 

i 84, 700

i 33, 800 

1 14, 100

i 13. 000

Percent in indicated size range

< 0.005 

mm.

25.4 

7.3 

37.0 

35.2 

14.1 

39.2

17.8 

3.2 

7.8 

34.6 

21.0

6.1 

28.3 

10.1 

3.2 

.8 

4.8 

6.7 

2.4

4.5 

.9 

.7 

.9

.7 

3.6 

2.7

3.7 

3.7 

4.0 

6.3

7.5 

2.0 

3.4 

3.3 

1.7 

3.8 

2.8 

2.6 

8.1

15.7 

1.9 

1.9 

3.2 

1.1 

3.2 

1.1 

4.5

1.2 

1.8 

3.6 

2.0

1.4 

5.5

1.5

0.005- 

0.020 

mm.

17.4 

13.3 

9.1 

14.6 

44.5 

22.5

33.2 

29.2 

39.9 

29.5 

17.7

36.8 

14.6 

10.9 

23.3 

24.0 

28.5 

23.5 

22.1

15.8 

16.6 

9.2 

15.0

8.8 

10.9 

42.7

18.6 

29.3 

27.9 

71.2

57.7 

81.4 

84.4 

65.4 

90.2 

86.6 

89.3 

91.5 

86.5

74.8 

83.7 

74.4 

79.4 

80.9 

79.0 

90.0 

75.7

71.0 

79.6 

78.5 

77.4

69.7 

61.9

66.3

0.020- 

0.050 

mm.

21.0 

27.0 

19.7 

16.7 

13.6 

14.1

16.4 

15.9 

18.7 

13.9 

14.2

17.0 

13.4 

16.0 

16.6 

14.8 

13.7 

14.1 

13.4

16.6 

14.7 

9.5 

11.3

5.3 

9.9 

15.5

24.7 

19.0 

19.1 

12.7

21.1 

13.8 

9.6 

22.3 

6.5 

8.3 

7.0 

5.1 

4.0

6.1 

12.1 

13.4 

11.1 

7.0 

6.7 

4.8 

13.3

15.1 

10.9 

11.6 

11.7

16.4 

18.5

19.6

0.050- 

0.074 

mm.

20.4 

40.9 

23.7 

22.3 

14.1 

15.2

18.4 

14.1 

10.3 

10.2 

17.1

19.6 

15.3 

18.2 

18.6 

19.5 

19.6 

16.1 

14.7

15.6 

24.2 

16.4 

13.9

9.9 

12.3 

10.0

13.9 

17.0 

13.4 

4.3

6.9 

1.5 1.4* 

5.7 

.5 

.2 

.2 

.2 

.2

1.4 

1.2 

7.5 

3.5 

5.8 

5.3 

1.8 

3.1

5.6 

3.1 

3.8 

4.3

6.1 

7.1

7.4

0.074- 

0.149 

mm.

13.3

8.8 

9.5 

9 5 

10^4 

7.6

13.4 

28.5 

20.2 

9.8 

26.1

18.9 

22.9 

42.2 

34.8 

30.7 

21.3 

27.6 

22.1

24.5 

25.1 

28.6 

27.8

35.1 

25.2 

14.4

13.8 

3.3 

15.8 

3.5

5.0 

.9 

.9

2.7 

.8 

.8 

.4 

.4 

.8

1.4

.7 

2.4 

2.2 

4.2 

4.9 

1.9 

2.2

5.7 

3.5 

1.7

2.7

4.5 

4.2

4«,e:

> 0.149 

mm.

2.5 

2.7 

1.0 

1.7 

3.3 

1.4

.8 

9.1 

3.1 

2.0 

3.9

1.6 

5.5 

2.6 

3.5 

10.2 

12.1 

12.0 

25.3

23.0 

18.5 

35.6 

31.1

40.2 

38.1 

14.7

25.3 

27.7 

19.8 

2.0

 1.8 

.4 

.3 

.6 

.3 

.3 

.3 

.2 

.4

.6 

.4

.4 

.6 

1.0 

.9 

.4 

1.2

1.4 

1.1 

.8 

1.9

1.9

2.8

1.2

1 Mean for days on which size samples were collected.

725806 47- -11
156 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 23, Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Grand Canyon, Ariz., Apr. 5, 1935, to 

Sept. 30, 1941 Continued

Date of collection

1939

Jan. 1, 4, 7, 10, 13, 16, 19, 

22,25,28,30 

Feb. 2, 5, 8, 11, 14, 17, 20, 

23.. .

Feb. 26. 

Mar. 1,5, 8,11,14. .

Mar. 18 - 

Mar. 23 - 

Mar. 24 

Mar. 26 

Mar. 28 

Mar. 31 

Apr. 2__ . ...

Apr. 14-. 

Apr. 20, 23, 26 .

Apr. 29. ... 

Mayl ... ... 

May 3 .. 

May 7.--. .

May 13 

May 16, 18, 22_... .. ...

May 25, 28, 30-.. ....

Junel, 5, 8,11,13 . 

June 1& 18, 20, 23, 26, 29.. 

July 2, 5, 8, 11, 14-- 

July 17, 20, 23, 26. . ....

Aug. 11, 15, 18,21...... _

Aug. 24, 27, 30, Sept. 2. ...

Sept. 7 

Sept. 11 ...

Sept. 13 ... .

Sept. 14. ... .....

Sept. 21...... ..... ........

Sept. 24 ....

Sept. 29, Oct. 2, 5, 8, 11---

Oct, 14, 17, 20, 23, 26, 29... 

Nov. 1,4,7,10,13 - 

Nov. 16, 19, 22, 25, 28.- 

Dec. 1,4,7,10,13-.... .

Dec. 16, 19, 22, 25, 28, 31 

Mean 

daily discharge 

(sec. -ft.)

15,880

i 5,660 

5,910

16,350 

9,240 

10, 400 

11,200 

21, 100 

27,400 

28,500 

27,000 

27,800

23,700 

19,500 

25, 400 

22,600 

21, 500 

1 16, 400 

21,000

22,500 

29, 600 

33,400 

40, 600 

45,300 

40, 100 

i 39, 000 

i 41, 700

i 36, 300 

i 21, 600

i 10, 100 

i 5, 740 

i 4, 180 

i 4, 520 

13,100

5,140 

8,540 

10,300 

13,200 

17,300 

25,200 

18,100 

14,800 

12,600 

9,970 

7,720 

6,300 

16,350

i 5, 790 

15,460 

15,600

1 5, 270 

i 4, 780

Suspended sediment

Mean 

daily con- centration (percent)

10.04

i.04 

.08

1.07 

.28 

.54 

.89 

1.82 

1.84 

2.06 

1.83 

1.45

1.10 

.88 

1.36 

.83 

.58 

1.33 

.42

.53 

.84 

.94 

1.12 

1.17 

.77 

1.65 

1.61

1.44 1.20

1.04 

1.02 

i.Ol 

1.16 

1.16

.68 

1.65 

1.84 

1.58 

4.66 

6.37 

5.YO 

3.82 

2.36 

1.58 

.99 

.49 

1.39

1.16 

1.09 

1.08

1.06 

1.07

Tons per 

day

i 6, 130

i 5, 020 

12, 800

i 12, 600 

69, 900 

152,000 

269,000 

1, 040, 000 

1, 360, 000 

1, 590, 000 

1, 330, 000 

1, 090, 000

704,000 

463,000 

933, 000 

506,000 

337, 000 

. i 145, 000 

238, 000

322,000 

671, 000 

848, 000 

1, 230, 000 

1, 430, 000 

834,000 

i 686, 000 

i 699, 000

i 435, 000 

i 127, 000

i 12, 200 

i 3, 100 

i 1, 120 

i 19, 100 

i 14, 400

94,400 

380,000 

512,000 

563,000 

2, 180, 000 

4, 330, 000 

2, 790, 000 

1, 530, 000 

803, 000 

425,000 

206,000 

83,300 

i 67, 900

i 24, 500 

i 13, 300 

i 16,000

i 8, 250 

i 9, 110

Percent in indicated size range

< 0.005 

mm.

3.1

14.1 

11.3

3.3

3.5 

1.7 

.9 

.4 

.5 

1.2 

.6 

.4

.8 

.9 

.7 

1.1 

1.3 

1.3 

3.9

3.7 

1.7 

1.7 

6.6 

2.2 

5.8 

.5 

1.1

.5 

.9

4.0 

28.5 

29.9 

1.2 

1.3

1.6 

.9 

2.4 

.8 

.4 

1.0 

1.9 

2.5 

3.1 

3.8 

1.2 

2.6 

.7

.8 

2.3 

2.9

5.4 

4.4

0.005- 

0.020 

mm.

65.8

38.1 

75.7

60.2 

51.5 

61.8 

70.8 

35.0 

31.4 

35.9 

56.6 

45.9

51.2 

52.0 

45.7 

39.3 

31.9 

23.7 

16.9

25.9 

10.6 

14.5 

13.0 

13.6 

10.3 

13.3 

7.5

14.8 

14.8

41.6 

41.4 

43.1 

91.1 

86.6

88.1 

91.1 

87.9 

77.9 

86.3 

61.0 

64.0 

72.8 

64.3 

70.7 

85.5 

87.2 

94.6

92.1 

82.3 

73.5

75.6 

72.8

0.020- 

0.050 

mm.

20.9

36.9 

7.0

24.0 

25.9 

18.0 

10.8 

21.6 

17.0 

16.3 

12.4 

10.1

13.2 

13.2 

14.1 

16.6 

18.1 

19.0 

22.9

24.2 

16.1 

22.1 

17.1 

16.7 

16.3 

16.2 

18.6

16.3 

14.7

22.1 

19.0 

15.6 

6.9 

11.6

9.4 

6.7 

6.6 

13.8 

9.2 

17.7 

19.2 

15.9 

23.8 

21.3 

11.2 

8.3 

2.8

4.5 

11.8 

17.7

13.6 

17.1

0.050- 

0.074 

mm.

6.7

7.3

3.7

9.6 

12.9 

13.2 

12.1 

26.4 

25.7 

19.1 

11.3 

10.6

11.8 

11.0 

14.1 

13.9 

15.3 

16.7 

20.1

20.5 

22.1 

21.4 

16.4 

17.0 

16.7 

19.1 

19.3

21.1 

19.8

15.8 

6.4 

2.8 

.3 

.2

.3 

.6 

1.5 

3.6 

2.0 

12.4 

10.1 

5.6 

4.3 

2.4 

1.2 

1.2 

.7

1.4 

2.0 

3.4

3.1 

2.9

0.074- 

0.149 

mm.

2.6

2.4 

1.4

2.2 

4.6 

4.6 

4.6 

15.0 

22.5 

23.7 

15.7 

25.5

17.7 

16.2 

22.4 

23.8 

28.9 

31.6 

31.7

22.5 

44.0 

31.8 

34.5 

34.8 

28.5 

31.2 

32.8

27.4 

27.9

10.7 

3.1 

6.3 

.3

.2

.4 

.5 

1.3 

2.7 

1.5 

6.8 

4.1 

2.5 

2.9 

1.5 

.7 

.5 

.9

.9 

1.0

1.7

1.3 

1.9

> 0.149 

mm.

0.9

1.2 

.»

.7 

1.6 

.7 

.8 

1.6 

2.9 

3.8 

3.4 

7.5

5.3 

6.7 

3.0 

5.3 

4.5 

7.7 

4.5

3.2

5.5 

8.5 

12.4 

15.7 

22.4 

19.7 

20.7

19.9 

21.9

5.8 

1.6 

2.3 

.2 

.1

.2 

.2 

.3 

1.2 

.6 

1.1 

.7 

.7 

1.6 

.3 

.2 

.2 

.3

.3 

.6 

.8

1.0

.9

' Mean for day on which size samples were collected.
QUANTITIES OF SUSPENDED SEDIMENT 157

TABLE 23. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Grand Canyon, Ariz., Apr. 5, 1935, to 

Sept. 30, 1941 Continued

Date of collection

Jan. 4, 7,10, 13 

Jan. 15 --.-_-----_--

Jan. 18 -----------------

Jan. 21, 24, 27,30, Feb. 2. .

Feb. 5.- 

Feb. 7-- - 

Feb. iO-_ _- 

Feb. 13,16.. 

Feb. 19, 22, 25, 28.

Mar. 2____. 

Mar. 4___... 

Mar. 7 .._. 

Mar. 9.__.... 

Mar. 12 - 

Mar. 15, 18, 21. 

Mar. 24____ 

Mar. 27 ._.

Apr. 2, 9, 12, 21, 24. 

Apr. 25-26, 29 

May 1-2, 5 . .. 

May 10-11,14, 17", 20 

May 25--- - - --. 

May 28,31---..-..-.....-.

June3, 5, 8.... 

June 10,12___ -.- 

June 15, 21, 25, 29-

July2, 6 - 

July 9, 13,17, 20, 23. 

July 27.... ... 

July 29 ..... 

July 31 ....... 

Aug. 3.. 

Aug. 6... 

Aug. 14. 

Aug. 17. 

Aug. 20. 

Aug. 24. 

Aug. 29..

Sept. 3... 

Sept. 7... 

Sept. 11. 

Sept. 14. 

Sept. 15. 

Sept. 17. 

Sept. 19. 

Sept. 21. 

Sept. 24. 

Sept. 26. 

Sept. 28.

Oct. 1- 

Oct. 3- 

Oct. 5.. 

Oct. 8... 

Oct. 12. 

Oct. 15. 

Oct. 19. 

Oct. 23- 

Oct. 29.

Mean 

daily discharge 

(sec.-ft.)

i 4, 730

7,170

5,870

i 4, 030

6,870

7,400

6,410

15,460

i 5, 160

7,820

8,610

6,990

9,000

8,520

17,250

6,500

6,940

i 10, 100

1 18, 900

i 22, 000

i 36, 900

34,800

i 32, 400

'38,500

'30,200

i 17, 800

110,600

16,180

4,660

5,740

5,340

4,260

3,130

2,350

5,060

2,570

4,940

7,130

5,530

6,030

4,110

7,270

8,980

5,530

11,300

12,700

14,200

11,200

9,030

22,300

19.200 

1(5,900

17,700

13,000

10,600

8,520

7,300

7,070

Suspended sediment

Mean

daily concentration (percent)

i.07

.63

.21 1.07

.18

.57

.34 1.17

1.08

.24

.95

.57

.55

.45

1.25

.17

.18

1.45

. i 1. 10

1.89

i 1.11

.64

1.50

.63

.44

.15

.07

.10

.10

2.93

1.24

1.94

1.70

.09

2.26

2.64

4.93

4.65

1.58

1.14

.60

.87

4.83

3.12

4.97

4.25

3.56

3.28

2.88

8.06

4.61 

2.86

3.62

1.44

1.03

.66

.34

.84

Tons per 

day

19,320

122,000

33,300

18,280

33, 400

114,000

58,800

125,200

i 1, 120

50,700

221, 000

108, 000

134, 000

104, 000

i 50, 600

29,800

33,700

i 123, 000

i 548, 000

i 536, 000

i 1, 130,-DOO

601, 000

i 437, 000

i 661, 000

1 368, 000

175,800

120,000

i 19, 800

12,600

454,000

179,000

223, 000

144,000

5,710

309,000

183,000

658, 000

895,000

236, 000

186, 000

66,600

171,000

1, 170, 000

466,000

 1,520,000

1, 460, 000

1, 360, 000

992,000

702,000

4J£50i.,000

2, 390, 000 

1, 300, 000

1, 730, 000

505,000

295,000

152,000

67,000

160,000

Percent in indicated size range

< 0.005

mm.

5.5

2.6

5.4

5.1

10.0

1.3

3.6

3.4

2.6

5.2

.7

1.6

2.4

2.3

1.5

3.2

1.8

.2

.4

.3

.3

.3

1.1

.6

1.2

5.4

12.0

2.0

9.3

1.1

1.4

.7

1.4

10.3

1.7

2.4

1.0

1.8

2.2

2.4

2.2

.8

1.5

1.1

.7

.7

1.3

1.0

2.7

2.2

2.9 

3.3

3.9

1.8

2.6

3.0

3.2

3.3

0.005- 

0.020

mm.

72.2

78.3

77.9

76.2

65.0

85.4

80.5

83.2

74.8

53.7

78.1

80.1

59.2

52.5

69.0

63.2

49.8

41.3

28.4

30.3

21.0

3.1

13.9

10.2

16.3

21.1

33.9

81.3

82.6

87.0

86.4

96.6

90.3

80.2

73.6

86.0

57.8

83.4

82.6

83.4

78.0

86.9

74.2

86.4

57.8

68.4

74.2

78.3

75.7

49.0

52.8 

71.4

65.0

73.1

73.0

69.7

25.0

75.6

0.020- 

0.050

mm.

15.7

14.9

13.4

13.9

18.0

9.8

12.5

9.4

15.0

23.6

13.3

12.3

19.9

24.9

14.9

19.4

18.8

14.3

20.5

12.5

11.7

3.4

13.3

10.5

12.7

15.1

19.7

- 12.4

5.5

10.7

11.2

2.3

7.9

7.8

22.1

11.2

11.2

10.0

13.2

12.8

18.0

10.1

13.5

8.2

20.1

10.8

10.6

10.3

13.6

15.6

21.8 

13.6

16.3

10.5

11.4

9.9

57.4

13.4

0.050- 

0.074

mm.

3.1

3.0

1.8

3.1

4.8

2.1

1.9

2.8

4.6

13.8

5.7

4.3

14.5

15.1

10.0

11.2

21.1

25.4

31.5

22.0

14.9

4.9

19.5

19.3

20.9

26.0

16.3

2.6

1.3

.7

.3

.2

. .2

1.0

2.1

.2

.8

3.4

1.5

1.1

1.3

1.8

8.0

3.1

9.8

11.2

7.7

5.6

4.4

16.1

11.5 

7.1

8.2

6.2

6.2

5.6

6.1

3.7

0.074- 

0.149

mm.

2.3

.8

.9

1.3

1.5

1.0

1.1

.9

1.4

3.0

1.8

1.4

3.5

4.6

3.5

2.3

6.9

16.1

18.0

31.2

37.4

12.1

29.9

36.1

30.1

19.8

13.2

1.3

.7

.3

.4

.1

.1

.3

.3

.1

.1

1.2

.4

.2

.4

.3

2.4

1.0

9.6

8.4

5.6

4.3

3.2

15.5

9.3 

3.9

5.3

6.6

5.9

8.8

6.0

3.1

> 0.149

mm.

1.2

.4

.6

.4

.7

.4

.4

.3

1.6

.7

.4

.3

.5

.6

1.1

.7

1.6

2.7

1.2

3.7

14.7

76.2

22.3

23.3

18.8

12.6

4.9

.4

.6

.2

.3

.1

.1

.4

.2

.1

29.1

.2

.1

.1

.1

.1

.4

.2

2.0

.5

.6

.5

.4

1.6

1.7

.7

1.3

1.8

.9

3.0

2.3

.9

i Mean for days on which size samples were collected.
158 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 23. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River .at gaging station near Grand Canyon, Ariz., Apr. 5, 1985, to 

Sept. 80, 194.1 Continued

Date of collection

1940 

Nov. 9- _ ---. __ - 

Nov. 12,17,19.- 

Nov. 23 

Nov. 26 - 

Nov. 30 

Dec. 3, 7 -

Dec. 10, 14 

Dec. 17 ------------

Dec. 21.. 

Dec. 31-.. --------------

1941 

Jan. 4 

Jan. 14 _ -_

Jan. 21 . ---..---__-__..

Feb. 15....... ...-.._

Feb. 25... ...- _

Mar. 1 ..... ...... - .

Mar. 15 

Mar. 18 

Mar.29 

Apr. 5_- ____ . _ _- 

Apr. 26-. __ _ ..... .._

May 6 _ __ __ ....

May 26 ________ _ _

June 5 __ - H

June 12-... __ _____ .

June 28.. ...

July 1, 7, 21 

July 26-. ................

July 30 ........ 

Aug. 12 

Aug. 30-. . .. .. 

Sept. 16.. ._ _____ . ....

Sept. 24-. 

Sept. 27__ . . ..-.

Sept. 30 - ...

Mean 

daily discharge 

(sec.-ft.)

6,760 

i 6, 450 

8,770 

7,650 

6,770

1 6, 140 

i 6, 990 

7,580 

4,300 

5,320 

8,740 

7,140

9,700 

7,590 

5,880

7,920 

16, 100

13,600 

8,410 

15, 100 

18, 000

20, 000 

20, 500

56, 900 

83, 100

69, 000 

77, 700 

70,100

i 37, 800 

20, 300 

15,600

i 11, 100 

23,500 

17, 500 

8,890

7,140 

5,350 

10, 100 

13, 600 

19, 300 

21, 200

Suspended sediment

Mean 

daily concentration (percent)

.34 

1.20 

.99 

.76 

.31

1.21 

1.24 

.62 

.24 

.50 

1.56 

.84

1.92 

3.44 

.52

.89 

2.17

1.58 

.48 

2.83 

1.86

2.17

.87

1.79 

1.28

.63 

1.46 

.72

1.31 

.49 

.67

1.15 

2.89 

2.07 

.82

.86 

.39 

1.68 

1.80 

2.71 

1.88

Tons per 

day

62, 100 

i 34, 700 

234, 000 

157, 000 

56, 700

i 34, 800 

i 46, 400 

127, 000 

27, 900 

71, 800 

368, 000 

162, 000

503, 000 

705, 000 

82, 600

190, 000 

943, 000

580, 000 

109, 000 

1, 150, 000 

904, 000

1, 170, 000 

482, 000

2, 750, 000 

2, 870, 000

1, 170, 000 

3, 060, 000 

1, 360, 000

i 371, 000 

269, 000 

282, 000

i 49, 200 

1, 830, 000 

978, 000 

197, 000

166, 000 

56, 300 

458,000 

661, 000 

1, 410, 000 

1, 080, 000

Percent in indicated size range

< 0.005 

mm.

3.5 

4.8 

2.2 

2.8 

 5.3

4.2 

3.9 

2.5 

7.9 

3.6 

1.5 

2.3

1.1 

1.1 

1.5

.6 

.6

1.5 

1.6

.7

.7

1.1 

1.7

.8 

1.2

2.2

.9 

2.4

4.9' 

2.5 

2.7

3.6 

1.2 

1.6 

2.8

2.1 

3.9 

.6 

1.3 

1.4 

.7

0.005- 

0.020 

mm.

60.3 

54.4 

62.5 

65.8 

63.0

41.2 

28.0 

42.2 

74.4 

86.3 

58.0 

73.5

64.7 

68.6 

65.9

32.7 

50.7

63.0 

56.2 

60.9 

39.1

41.9 

44.4

29.6 

41.0

19.2 

33.8 

11.5

20.6 

68.2 

81.4

76.9 

65.6 

78.7 

86.1

90.9 

90.9 

87.1 

68.1 

67.3 

47.1

0.020- 

0.050 

mm.

13.7 

14.1 

9.4 

8.4 

9.4

10.2 

16.8 

10.5 

10.8 

2.7 

13.2 

7.9

8.9 

11.0 

5.5

10.4 

13.3

12.1 

9.4 

9.8 

13.6

12.6 

13.4

15.4 

14.3

15.1 

11.9 

11.3

15.0 

12.8 

6.9

11.7 

15.0 

12.7 

9.0

6.3 

3.8 

9.0 

13.8 

14.5 

10.6

0.050- 

0.074 

mm.

11.9 

9.9 

9.6

8.7

7.7

13.0 

17.1 

14.0 

2.7 

3.8 

16.0 

8.4

9.8 

8.0 

7.6

18.9 

12.5

11.1 

12.7 

10.4 

15.0

15.8 

18.5

17.5 

16.1

27.1 

13.0 

15.6

20.7 

8.2 

3.9

4.6 

10.8 

4.4

.7

.3

.7 

2.2 

8.3 

10.4 

15.7

0.074- 

0.149 

mm.

8.1 

12.3 

14.0 

11.2 

10.5

24.5 

22.5 

22.5 

3.0 

2.6 

10.5 

6.5

13.3 

10.0 

13.0

32.1 

17.8

11.2 

16.7 

15.0 

21.4

21.8 

17.0

24.7 

18.6

22.3 

22.7 

25.2

25.1 

6.1 

3.8

2.4 

6.4 

2.2 

1.0

.2

.7 

1.1 

7.7 

5.8 

24.1

> 0.149 

mm.

2.5 

4.5 

2.3 

3.1 

4.1

6.9 

11.7 

8.3 

1.2 

1.0 

.8 

1.4

2.2 

1.3 

6.5

5.3 

5.1

1.1 

3.4 

3.2 

10.2

6.8 

5.0

12.0

8.8

14.1 

17.7 

34.0

13.7 

2.2 

1.3

.8 

1.0 

.4 

.4

.2

.8 

.6 

1.8

1 Mean for days on which size samples were collected.
QUANTITIES OF SUSPENDED SEDIMENT 159

TABLE 24. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Willow Beach, Ariz., Apr. 2,1935, to Sept. 27, 

1936

[Samples collected prior to May 4,1936, dispersed with 1.5 percent sodium oxalate]

Date of collection

1935 

Apr. 2 .....

Apr. 5... ...

Apr. 9........ ..

Apr. 12.. ...... ..... ..

Apr. 16 .

Apr. 20-....

Apr. 22......

Apr. 23_. ...... .... ,.

Apr. 26. _...._....._......

Apr. SO-....

May I., __________ .

May 3.. __ .

May 5_ ____ ..

May 7. ____ __ ... ._

May8._...

May 10-.-.

Mav 14

May 15--..... ...

Mav 17...

May 21-. ...

Mav 22, 26-28

May 29, 31 . .... ..

June 1

June 5

June 7.

June 9 ...

June 10..-..

June 11 ....

June 14

June 21. ..

June24______

June 25......

June 26

June 28

July 4

July 10 . .

July 11

July 14... ...

July 18

July 21. ..

July 25... ...

July 28... ...... ...

Aug. 1. _____ . ____ .

Aug. 4_ __ . ____ .....

Aug. 8... ...........___._.

Aug. 11. ..................

Aug. 15... ...........

Aug. 18, 22, 25, 29 

Sept. 1..... ...............

Sept. 3---.-. ...... ......

Sept. 6... _ __ __

Sept. 9....................

Sept. 12...................

Sept. 19-.--.-.. ...... .

Sept. 22 . .. __ ......

Sept. 26... ................

Sept. 29:... .. .... .

Mean 

daily discharge 

(sec. -ft.)

7,690 

7,550 

7,320 

7,450 

6,860 

7,320 

7,520 

7,380 

7,420 

7,280

6,470 

7,350 

7,720 

7,350 

7,320 

7,120 

6,520 

6,610 

6,610 

6,930 

i 13, 100 

i 15, 000

15,200 

15,800 

16, 300 

16,200 

16, 400 

16, 800 

17, 300 

18, 600 

16,800 

14,400 

14, 500 

14,700

15,000 

10,000 

10,200 

10,000 

9,960 

10,000 

9,960 

10, 000

10,100 

10,000 

10, 200 

30, 100 

10,300 

» 10, 200

10, 100 

9,960 

10, 100 

9,960 

10, 100 

10, 100 

10,000 

9,960 

10,100 

9,920

Suspended sediment

Mean 

daily concentration (percent)

0.06 

.07 

.38 

.70 

1.15 

.24 

.04 

.04 

.40 

.06

.04 

.03 

.03 

.05 

.04 

.04 

.10 

.06 

.06 

.04 

'.08 

1.06

.06 

.06 

.05 

.04 

.06 

.05 

.04 

.05 

.04 

.04 

.05 

.05

.07 

.04 

.04 

.02 

.01 

.04 

.03 

.02

.04 

.03 

.04 

.07 

.01 '.02

.03 

.86 

.17 

.70 

1.37 

.01 

.01 

.03 

.01 

.02

Tons per 

day

12, 400 

14,300 

75, 100 

141, 000 

213, 000 

47,400 

8,120 

7,960 

80, 100 

11,800

6,990 

5,940 

6,260 

9,940 

7,910 

7,690 

17, 600 

10, 700 

10, 700 

7,480 

i 29, 300 

1 24, 200

24, 600 

25, 600 

22 000 

17^500 

26, 600 

22,700 

18, 700 

25, 100 

18, 100 

15, 600 

19,600 

19, 800

28, 300 

10, 800 

11,000 

5,400 

2,000 

10, 800 

8,080 

5,400

10, 900 

8,100 

11, 000 

19, 100 

2,780 

1 6, 760

8,180 

231, 000 

46,400 

188, 000 

374, 000 

2,730 

2,700 

8,070 

2,730 

5,350

Percent in indicated size range

<0. 005 

mm.

48.2 

56.1 

46.0 

3.3

52.6

34.2 

52.3 

28.0 

46.8

0.005- 

.020 

mm.

4.8 

4.9 

26.7 

36.6 

43.5 

78.5

35.8

62.0 

40.0 

68.6 

48.9

0.020- 

.050 

mm.

5.0 

7.4 

3.6 

3.4 

4.4 

5.5

3.5

1.6 

2.6 

2.3 

2.5

0.050- 

.074 

mm.

4.2 

9.3 

1.6 

.7 

.7 

12.7 

14.4 

18.0 

1.2 

13.9

14.2 

14.4 

12.4 

2.6 

34.8 

10.0 

2.3 

5.9 

12.6 

18.0 

15.7 

16.2

44.1 

12.0 

14.9 

18.0 

12.6 

27.6 

7.3 

24.4 

8.1 

16.1 

17.6 

12.1

8.5 

43.6 

17.4 

14.2 

15.2 

14.5 

16.0 

15.3

10.8 

29.1 

26.6 

15.8 

12.1 

2.1

16.9 

2.2 

5.1 

1.1 

1.8 

10.9 

8.6 

4.9 

8.6 

13.0

0.074- 

.149 

mm.

41.9 

50.9 

19.9 

3.2 

2.9

39.0 

40.4 

4.0 

53.6

33.6 

43.2 

56.6 

16.8 

55.1 

44.5 

17.8 

51.6 

40.1 

46.7 

51.2 

50.3

32.9 

42.3 

58.6 

57.0 

38.6 

36.2 

28.5 

41.1 

28.0 

47.8 

31.1 

33.0

37.1 

15.4 

19.5 

17.9 

28.4 

24.9 

19.5 

22.8

19.9 

18.3 

31.0 

14.7 

13.1 

7.0

24.2

12.1 

20.1 

13.8 

24.0 

33.6

>0. 149 

mm.

44.1 

27.5

2.5

46.6 

41.6 

2.9 

32.5

52.2 

 42.4 

31.0 

80.6 

10.1 

45.5 

79.9 

42.5 

47.3 

35.3 

33.1 

33.5

23.0

45.7 

26.5 

25.0 

48.8 

36.2 

64.2 

34.5 

63.9 

36.1 

51.3 

54.9

54.4 

41.0 

63.1 

67.9 

56.4 

60.6 

64.5 

61.9

69.3 

52.6 

42.4 

69.5 

74.8 

90.9

58.9

77.0 

71.3 

81.3 

67.4 

53.4

* Mean for days on which size samples were collected.
160 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 24. Mechanical analyses of suspended sediment in samples collected in the 

Colorado River at gaging station near Willow Beach, Ariz., Apr. 2, 1985, to Sept. 

27, 1936 Continued

[Samples collected prior to May 4,1936, dispersed with 1.5 percent sodium oxalate]

Date of collection

19S6

Oct. 6 ...........

Oct. 13 - 

Oct. 17..... ...............

Oct. 20, 24, 27, 31 

Nov. 3, 7, 10, 14,17 

Nov. 21, 24, 27, Dec. 1, 5, 

9, 12, 16, 19, 23-- - 

Dec. 26, 29--..... _ ....

1986 

Jan. 1-2, 5,9, 12, 16, 19, 23, 

26 

Jan. 30, Feb. 2, 6, 9, 13, 16, 

20, 23, 27, Mar. 1........

Mar. 5-6, 9, 12, 16, 19, 22, 

26, 29, Apr. 2 .........

Apr. 5,9, 12, 16, 19.......

Apr. Z2.. .................

Apr. 25.. _________ _.

Apr. 28-.. .............

May 4, 7, 10, 14, 17, 21, 24, 

28, 31... ....... ......

June 4, 7, 11, 14, 18, 21, 25, 

29,- .

July 2, 5, 9, 12, 16, 18, 23, 

26,30-- 

Aug. 2, 6, 9, 13, 16, 20, 23, 

27, 30...... .............

Sept. 6, 10-11, 13-14, 17-20, 

24,27...................

Mean 

daily discharge 

(sec.-ft.)

10, 000 

9,740 

9,680 

9,720 

9,820 

1 9, 840

1 9, 700 

'6,340

 '4,840

i 5, 630

i 9, 250

i 9, 670 

9,840 

9,960 

10, 700

9,460 

1 9, 350

110,400 

i 11, 300 

1 9, 980 

19,480

Suspended sediment

Mean 

daily concentration (percent)

.02 

1.57 

2.16 

.34 

.01

!.01

i.04 

1.02

i.Ol

i.Ol

1.02

1.02 

.21 

1.41

.74

.10 

i.Ol

i.Ol 

i.Ol 

i.Ol 

i.Ol

Tons per 

day

5,400 

413, 000 

565, 000 

89,200 

2,380 

i 3, 330

i 10, 500 

13,480

i 1, 030

i 1, 020

i 5,640

i 4, 720 

55, 800 

379, 000 

214, 000

25, 500 

i 3, 010

i 3, 050 

12,720 

1 2,050 

11,740

Percent in indicated size range

<0.005 

mm.

68.6 

74.5 

73.9

58.1 

67.8 

13.0

57.3

0.005- 

.020 

mm.

27.2 

21.8 

4.8

14.6 

28.2 

81.6

27.1

0.020- 

.050 

mm.

3.6 

2.6 

2.2

2.3 

3.9 

2.4

5.2

0.050- 

.074 

mm.

3.7 

.6 

1.1 

IS. 1 

14.2 

13.9

1.4 

9.2

8.2

6.1

8.3

8.0 

1.9 

.1 

3.0

1.7 

16.0

~6.7 

8.2 

5.4 

8.0

0.074- 

.149 

mm.

35.1

20.8 

23.7

5.2 

17.4

3.8

1.2

17.7

12.0 

4.7

3.6 

23.2

16.6 

17.7 

,10.5 

14.1

>0. 149 

mm

61.2

65.0 

62.4

93.4 

73.4

88.0

92.7

74.0

80.0 

18.4

5.1 

60.8

76.7 

74.1 

84.1 

77.9

i Mean for days on which size samples were collected.
QUANTITIES OF SUSPENDED SEDIMENT 161

TABLE 25. Mechanical analyses of suspended sediment in samples collected in the 

San Juan River at gaging station near Bluff, Utah, May 8, 1985, to Sept. SO,

[Samples collected prior to May 4,1936, dispersed with 1.5 percent sodium oxalate]

Date of collection

1935 

May3 __________

May 11. ..............

May 14. __ .... ........

May IS.......

May 19.. _ . .

May 21. .......... .....

May 22... ...............

May 23. .................

May 25.. .....

May 27-----.. . .

May 28....... .... . ..

May 20..................

June 1_. _ ,

June 3... .....

June 6.. _____ .

June 7. _ .

June 8........

June 14.

June 17. ......

June 27-.- __

June 29. ......

July 1...... _____________

Julys.... .....

July5 .-..

July? ..,.___________

July 9 ..................

July 11.. ..................

July 13........

July 15... .........

July 17. .........

July 19 ...............

July 20... - _ __..__

July 24... ......

July 26_... ......... ..

July29 _____________

July 31... - _____.______

Aug. 9. __ ...... ________

Aug. 13...................

Aug. 15....... . .

Aug. 19. _._.._..__..

Aug. 22 .._._

Aug. 25.----.......... _

Aug. 29 ._...__

Sept. 1. __ ..

Sept. 3... _ .. .

Sept. IS....... .

Sept. 15......,-...-.

Sept. 18 _

Sept. 20 ....

Sept. 23 __ _

Sept. 24... ____. _

Sept. 25. _ -_

Sept. 28... .... . .

Mean 

daily discharge 

(sec. -ft.)

4,230 

3,660 

3,940 

6,120 

5,960 

6,460 

7,140 

11,300 

8,590 

6,970 

8,590 

9,160 

9,160

8,780 

6,800 

8,780 

10,100 

11,500 

13, 300 

17, 100 

16, 100 

18,500 

11, 100 

10, 100

8,590 

7,860 

7,140 

6,290 

5,960 

5,640 

5,000 

4,680 

4,380 

5,800 

3,940 

3,660 

2,550 

3,820 

2,730

2,610 

2,140 

2,670 

2,800 

1,670 

1,720 

1,440 

964 

2,140 

2,550

2,730 

1,770 

1,060 

842 

694 

530 

452 

559 

3,940 

9.290

Suspended sediment

Mean 

daily con 

centration (per 

cent)

1.02 

.98 

.86 

1.32 

1.83 

1.81 

1.25 

2.51 

1.99 

1.16 

1.17 

1.35 

1.08

1.01 

.82 

.94 

.99 

1.06 

1.19 

1.17 

1.00 

1.03 

.72 

.81

.87 

.65 

.70 

.72 

.69 

.54 

.46 

.53 

.78 

2.71 

1.17 

.54 

.52 

1.28 

1.77

4.45 

2.48 

3.40 

4.13 

2.13 

1.70 

1.11 

.43 

2.63 

2.25

2.08 

4.67 

.95 

.57 

.31 

.27 

.38 

3.91 

5.95 

8.42

Tons per 

day

116, 000 

96, 800 

91,500 

218, 000 

295, 000 

316, 000 

241, 000 

766,000 

462, 000 

218,000 

271,000 

334,000 

267, 000

239,000 

151, 000 

223, 000 

270, 000 

329, 000 

427, 000 

540, 000 

435, 000 

514,000 

216, 000 

221, 000

202, 000 

138. 000 

135, 000 

122, 000 

111, 000 

82,200 

62, 100 

67.000 

92, 200 

424, 000 

124, 000 

53,400 

35, 800 

62, 900 

19, 800

314, 000 

143, 000 

245,000 

312, 000 

96, 000 

78,900 

43,100 

11,200 

152, 000 

155,000

153,000 

223,000 

27,200 

13, 000 

5,800 

3,860 

4,640 

59,000 

633,000 

2.260.000

Percent in indicated size range

<0.00 

mm.

8.3 

21.8 

9.2 

12.2 

15.4 

7.8 

14.9 

11.2 

26.8 

11.4 

14.7 

14.1 

10.1

8.4 

8.5 

8.9 

14.0 

12.7 

12.0 

15.8 

13.9 

12. 1 

9.8 

8.8

6.2 

9.9 

9.4 

12.9 

10.2 

5.9 

9.1 

10.0 

35.6 

26.8 

39.2 

- 19.1 

18.7 

6.3 

5.8

27.0 

15.0 

30.4 

28.9 

43.5 

21.6 

40.6 

27.6 

35.5 

41.7

26.7 

29.5 

35.5 

27.4 

29.7 

15.3 

5.8 

8.2 

11.8 

29. s

0.005- 

.020 

mm.

5.4 

13.5 

10.5 

8.0 

8.9 

4.8 

7.2 

18.4 

19.7 

9.1 

9.6 

10.1 

10.4

7.5 

6.6 

11.4 

11.2 

11.2 

10.5 

12.6 

11.2 

10.1 

7.5 

10.4

4.3 

6.5 

6.9 

9.7 

6.8 

8.7 

5.8 

6.7 

14.6 

14.4 

19.4 

10.6 

9.7 

2.7 

2.6

29.5 

5.6 

17.0 

14.0 

16.5 

10.4 

18.3 

28.1 

31.3 

24.8

18.0 

16.4 

15.1 

13.4 

14.4 

25.7 

32.2 

12.8 

33.8 

20 n

0.020- 

.050 

mm.

10.9 

15.5 

21.1 

16.0 

17.6 

11.4 

13.2 

15.0 

16.6 

16.6 

16.5 

15.8 

10.2

13.2 

13.0 

22.1 

18.9 

16.3 

16.6 

15.3 

15.9 

13.7 

11.9 

19.5

6.5 

11.3 

11.2 

12.4 

9.4 

7.6 

8.3 

9.9 

5.6 

13.1 

9.0 

13.0 

10.8 

1.7 

1.4

6.4 

1.9 

5.8 

9.0 

4.8 

6.4 

6.4 

11.6 

15.3 

13.3

19.4 

12.5 

9.4 

10.6 

11.8 

9.8 

10.9 

20.3 

13.3

18 Q

0.050- 

.074 

mm.

21.8 

22.6 

26.1 

28.5 

27.0 

18.1 

21.5 

16.6 

2.1 

21.7 

23.8 

23.0 

25.5

20.9 

19.2 

30.3 

19.9 

18.0 

16.6 

19.4 

20.2 

16.9 

22.0 

26.8

15.6 

20.0 

20.1 

17.4 

18.1 

14.9 

13.8 

13.4 

9.1 

11.6 

7.3 

15.2 

18.3 

5.2 

3.4

5.3 

1.8 

3.1 

4.1 

2.6 

3.7 

2.8 

5.1 

5.7 

4.7

13.2 

15.4 

5.9 

13.5 

8.5 

11.6 

12.9 

31.7 

6.4

13 fi

0.074- 

.149 

mm.

37.2 

22.4 

26.6 

25.1 

22.9 

32.6 

27.8 

21.8 

24.4 

31.2 

27.7 

27.0 

28.-0

33.7 

30.5 

23.3 

25.2 

24.3 

26.2 

24.9 

27.5 

31.6 

32.9 

29.6

37.0 

38.1 

39.9 

34.6 

41.8 

36.7 

31.9 

33.2 

19.8 

21.3 

14.7 

29.3 

32.1 

43.2 

14.7

9.7 

12.4 

7.9 

9.6 

12.1 

17.8 

11.0 

17.4 

8.4 

7.6

13.8 

23.6 

23.3 

26.5 

30.6 

32.7 

31.5 

22.3 

16.9 

19 4.

>0. 149 

mm.

16.4 

4.2 

6.5 

10.2 

8.2 

25.3 

15.4 

17.0 

10.4 

10.0 

7.7 

10.0 

15.8

16.3 

22.2 

4.0 

10.8 

17.5 

18.1 

12.0 

11.3 

15. ft 

15.9 

4.9

30.4 

14.2 

12.7 

13.0 

13.7 

26.2 

31.1 

26.8 

15.1 

12.8 

10.4 

12.8 

10.4 

40.9 

72.1

22.1 

63.3 

35.8 

34.4 

20.5 

40.1 

20.9 

10.2 

3.8 

,8.0

8.9 

2.6 

10.8 

8.6 

5.0 

4.9 

6.7 

4.7 

17.8 

R fi
162 SEDIMENT IN COLORADO RIVER, 1925-41

TABLE 25. Mechanical analyses of suspended sediment in samples collected in the 

San Juan River at gaging station near Bluff, Utah, May 3, 1935, to Sept. 30, 

1936 Continued

[Samples collected prior to May 4,1936, dispersed with 1.5 percent sodium oxalate]

Date of collection

1935 

Oct. 7---.-..

Oct. 10 ---_ .......

Oct. 14... .................

Oct. 17 - _- _ .__

Oct. 19 ..

Oct. 22 ..... ----- .

Oct. 25- ._-_ - . ..

Oct. 28 . -----. ---------

Oct. 31 ......... ........

Nov. 3-

Nov. 6 ._ -

Nov. 12_ .....

Nov. 15-____._ _____ .

Nov. 18_ __ _ __ .._ __ ...

Nov. 21________. ______.__.

Nov. 24_ _..

Nov. 27-..---. _ Nov. 30 . 

Dec. 3_- .

Dec. 9...- ..

Dec. 10-.- - _

Dec. 16.................

Dec. 20... ................

Dec. 23-. 

Dec. 26--.....

Dec. 29............ ....

1936 

Jan. 1

Jan. 4 ..__

Jan. 7 -------

Jan. 13- ____ __ ..

Jan. 16 _ .

Jan. 19 .......

Jan, 22__ ____ __ . ...

Jan. 25_. _____ ... .....

Jan. 28 .

Jan. 31 -_ _ _ ...

Feb. 3------------..---.-.

Feb. 6-. --..... ........ ...

Feb. 9_.._ ........ ........

Feb. 13... .... ........

Feb. 16.................

Feb. 18-.. .............

Feb. 21-.-... .............

Feb. 24..................

Feb. 27-----...--..----..

Mar. 1 . ...... .

Mar. 4 ........

Mar. 7 ......... ....

Mar. 10- ____ _ Mar. 13 .__ .

Mar. 16 ___ ....

Mar. 19-.. ................

Mar. 22. ____ . _ .......

Mar. 25 ...... ........

Mar. 28..................

Mar. 31-- -------

Mean 

daily discharge 

(sec.-ft.)

1,260 

1,060 

872 

776 

720 

1,620 

932 

910 

842

762 

748 

688 

707 

643 

625 

655 

601 

707 

674

565 

668 

655 

496 

312 

348 

518 

420

559 

474 

518 

601 

694 

631 

452 

565 

880 

762

918 

607 

452 

681 

1,220 

1,060 

902 

798 

1,670

734 

3,120 

3,380 

3,120 

2,430 

2,670 

2,140 

1,820 

1,920 

1,260 

1.530

Suspended sediment

Mean 

daily concentration (percent)

.38 

.36 

.29 

.24 

.26 

1.90 

.99 

.55 

.40

.32 

.29 

 .24 

.25 

.26 

.22 

.21 

.26 

.29 

.24

.34 

.24 

.24 

.23 

.12 

.14 

.32 

.29

0.23 

.23 

.29 

.38 

.26 

.24 

.19 

.19 

.32 

.31

.39 

.24 

.14 

.25 

.86 

.66 

.59 

.48 

2.29

.79 

2.17 

3.25 

1.82 

1.53 

1.23 

1.00 

.74 

.64 

.44 

.56

Tons per 

day

12,900 

10, 300 

6,830 

5,020 

5,050 

83,100 

24,900 

13,500 

9,100

6,590 

5,860 

4,460 

4,780 

4,510 

3,730 

3,730 

4,210 

5,540 

4,370

5,180 

4,320 

4,240 

3,080 

999 

1,320 

4,480 

3,290

3,480 

2,940 

4,050 

6,160 

4,860 

4,080 

2,320 

2,890 

7,610 

6,370

9,670 

3,940 

1,700 

4,590 

28,300 

18, 900 

14,400 

10, 300 

103, 000

15, 700 

18,300 

297, 000 

153,000 

100,000 

88,700 

57,800 

36,400 

33,200 

15,000 

23.100

Percent in indicated size range

< 0.005 

mm.

36.1 

23.4 

26.9 

33.0 

21.9 

44.4 

17.9 

34.8 

36.7

34.1 

13.8 

36.2 

25.8 

35.7 

23.8 

25.8 

18.7 

17.3 

18.3

43.9 

34.3 

4.3 

17.0 

22.8 

13.0 

3.8 

5.6

2.9 

1.9 

2.0 

8.0 

2.4 

3.3 

2.0 

3.8 

2.1 

16.9

6.5 

5.3 

3.6 

20.1 

15.0 

47.4 

50.5 

38.1 

46.8

52.9 

46.1 

43.0 

37.2 

44.1 

33.3 

36.7 

29.5 

25.5 

24.1 

29.4

0.005- 

.020 

mm.

18.3 

13.7 

20.4 

17.2 

16.8 

25.8 

41.7 

21.0 

17.9

24.1 

31.9 

21.7 

16.7 

19.9 

15.0 

16.9 

14.5 

11.0 

21.5

8.4 

12.5 

2.4 

9.6 

8.8 

7.8 

3.1 

5.0

3.7 

.9 

5.8 

3.1 

6.0 

14.8 

2.9 

8.0 

10.5 

8.9

9.1 

7.8 

28.5 

11.3 

8.2 

15.6 

8.7 

8.4 

27.9

10.2 

18.7 

37.8 

18.7 

22.0 

19.6 

20.0 

19.5 

14.9 

18.4 

20.9

0.020- 

.050 

mm.

13.3 

9.8 

14.7 

16.3 

13.4 

8.3 

6.6 

10.8 

12.6

13.8 

13.1 

15.2 

15.2 

16.8 

14.8 

20.6 

16.0 

17.2 

14.8

9.7 

17.5 

2.9 

8.4 

10.4 

7.3 

5.5 

9.1

9.0 

2.4 

7.9 

3.7 

2.3 

4.5 

1.5 

2.9 

3.9 

5.1

7.9 

5.2 

10.4 

13.3 

13.6 

8.7 

7.0 

7.1 

6.3

6.5 

10.5 

11.2 

9.9 

13.8 

16.9 

1853 

22.8 

20.5 

19.2 

21.4

0.050- 

.074 

mm.

9.4 

8.5 

11.6 

10.0 

10.6 

6.1 

4.2 

8.6 

8.8

9.6 

13.8 

8.8 

10.7 

11.8 

12.3 

14.2 

13.5 

13.5 

14.6

6.4 

13.3 

8.5 

8.7 

11.8 

9.2 

8.7 

14.4

16.5 

5.1 

17.8 

10.4 

6.9 

10.8 

3.6 

5.3 

8.4 

8.3

7.9 

8.3 

6.8 

11.9 

14.5 

7.8 

6.3 

7.2 

5.1

4.3 

5.9 

4.0 

24.0 

7.6 

13.9 

11.6 

14.9 

16.2 

H.8 

14.4

0.074- 

.149 

mm.

15.6 

22.8 

18.2 

18.4 

22.1 

10.7 

13.2 

17.9 

16.6

13.4 

20.6 

13.5 

17.8 

13.4 

24.4 

18.5 

22.9 

28.0 

21.4

20.0 

17.9 

42.7 

27.9 

29.8 

28.5 31.9' 

39.0

45.2 

20.7 

43.0 

30.4 

33.5 

43.4 

23.0 

25.4 

41.4 

41.0

42.2 

41.5 

25.3 

32.6 

29.3 

13.6 

12.1 

21.7 

6.7

10.1 

12.0 

3.2 

7.0 

8.8 

12.5 

9.6 

11.2 

16.7 

18.9 

10.7

>0. 149 

mm.

7.3 

21.8 

8.2 

5.1 

15.2 

4.7 

16.4 

6.9 

7.4

5.0 

6.8 

4.6 

13.8 

2.4 

9.7 

4.0 

14.4 

13.0 

9.4

11.6 

4.5 

39.2 

28.4 

16.4 

34.2 

47.0 

26.9

22.7 

69.0 

23.5 

44.4 

48.9 

23.2 

67.0 

54.6 

33.7 

19.8

26.4 

31.9 

25.4 

10.8 

19.4 

6.9 

15.4 

17.5 

7.2

16.0 

6.8 

.8 

3.2 

3.7 

3.8 

3.8 

2.1 

6.2 

4.6 

3.2
QUANTITIES OF SUSPENDED SEDIMENT 163

TABLE 25. Mechanical analyses of suspended sediment in samples collected in the 

San Juan River at gaging station near Bluff, Utah, May S, 1985, to Sept. 80, 

1986 Continued

[Samples collected prior to May 4,1936, dispersed with 1,5 percent sodium ozalate]

Date of collection

19S6 

Apr. 3...........

Apr. 6----.--......

Apr. 9__ __

Apr. 12...... .

Apr. 14... .......

Apr. 17..........

Apr. 20. . _

Apr. 23... _ .

Apr. 26_ __ .

Apr. 29.........

May 2 ......

May 5 ........

May8...._ _ .

May 11

May 14.

May 17....

May 20 __ .

May 23

May 26 .

May 29. _ .

June 1

June 4

JuneS.

June 11..

June 14

June 17

June 20

June 23

June 26. ..

June 28...

July 1

July 4

Julys

July 11

July 14

July 17

July 20- .

July 23

July 26

July 29

Aug. 1. ......

Aug. 4........

Aug. 5___

Aug. 6.- ...

Aug. 7, ...

Aug. 10 __ .

Aug. 13-... ..

Aug. 16 -

Aug. 19 ...

Aug. 22-..

Aug. 25....

Aug. 28...... Aag.-ao...... .

Sept. 3.. -"' 

Sept. 6. .

Sept. 14 .

Sept. 17 ..

Sept. 20 .

Sept. 22,....

Sept. 26 .

Sept. 30-..

Mean 

daily discharge 

(sec.-ft.)

1,980 

1,770 

1,580 

4,230 

6,800 

7,140 

7,680 

7,680 

7,140 

6,800

5,480 

8,590 

10, 300 

4,840 

5,160 

6,460 

7,140 

7,320 

6,970 

6,630

7,320 

5,000 

2,990 

4,230 

4,080 

3,120 

2,490 

1,720 

1,400 

1,220

872 

769 

469 

430 

1,920 

918 

583 

607 

480 

357

326 

915 

3,950 

7,140 

6,460 

3,250 

1,670 

1,220 

1,140 

4,530 

1,180 

625 

5,440 ;

 $ .«&' 

3s,' 620'' 

1,720 

1,100 

1,260 

1,620 

1,260 

1,140

Suspended sediment

Mean 

daily con 

centration (per 

cent)

.86 

.75 

.82 

.99 

1.74 

1.41 

1.18 

.96 

.83 

.92

.64 

.88 

1.33 

.47 

.53 

.55 

.80 

.75 

.64 

.57

.80 

.49 

.35 

.35 

.34 

.24 

.23 

.16 

.17 

.14

.18 

.08 

.06 

.13 

1.16 

.33 

 .39 

.60 

.19 

1.33

.24 

2.25 

21.4 

8.81 

6.42 

1.79 

.74 

.43 

1.65 

5.03 

2.54 

.65 

6.56

 &:si

1.95 

1.54 

.52 

.80 

8.12 

1.73 

1.98

Tons per 

day

46,000 

35, 900 

35,000 

113,000 

319,000 

272, 000 

245,000 

199, 000 

160,000 

169,000

94, 700 

204, 000 

370, 000 

61, 400 

73, 800 

95, 900 

154, 000 

148, 000 

120, 000 

102, 000

158, 000 

66, 100 

28,200 

40,000 

37,400 

20,200 

15,500 

7,420 

6,430 

4,620

4,240 

1,670 

756 

1,510 

60,100 

8,180 

6,130 

9,830 

2,460 

12,800

2,110 

55,600 

2, 280, 000 

1,700,000 

1, 120, 000 

157, 000 

33,400 

14,200 

50, 800 

615,000 

80,900 

11,000 

964, 000

928,000 

185, 000 

71, 500 

15,400 

27,200 

355, 000 

58,900 

60,900

Percent in indicated size range

<0.00 

mm.

41.2 

28.7 

17.5 

26.2 

21.2 

23.2 

15.7 

17.0 

14.0 

9.9

11.8 

15.8 

11.3 

18.2 

10.7 

9.0 

6.7 

8.9 

14.4 

12.4

4.2 

5.4 

9 2 

8^4 

5.3 

8.1 

7.4 

9.2 

14.6 

15.1

42.5 

15.8 

5.5 

5.5 

34. > 

40.6 

54.6 

56.8 

21.2 

56.3

45.8 

42.5 

15.4 

43.5 

45.0 

47.9 

38.5 

46.8 

34.5 

42.6 

67.9 

54.9 

32.7

22.2 

28.4 

29.7 

33.5 

15.0 

27.7 

45.1 

29.0

0.005- 

0.020 

mm.

21.5 

16.3 

16.7 

17.9 

17.5 

17.0 

15.4 

10.4 

9.0 

6.4

18.1 

11.5 

7.8 

8.9 

6.0 

7.2 

3.9 

4.9 

9.2 

8.1

4.2 

5.2 

5.5 

7.6 

3.2 

4.2 

3.7 

4.4 

6.7 

7.0

11.7 

6.8 

3.1 

4.1 

29.5 

15.6 

17.6 

25.5 

11.3 

32.5

23.7 

32.5 

9.5 

26.0 

25.0 

21.5 

22.5 

16.9 

50.9 

28.4 

21.0 

28.3 

28.2

15.2 

29.0 

25.1 

13.4 

9.9 

23.1 

25.2 

32.2

0.020- 

0.050 

mm.

14.6 

15.1 

30.0 

18.9 

26.1 

23.2 

24.4 

19.2 

20.8 

9.2

16.6 

20.8 

15.1 

17.9 

10.2 

15.0 

10.2 

10.3 

15.6 

13.7

6.7 

3. 6 

9.3 

14.7 

5.4 

7.6 

7.1 

7.6 

6.1 

5.9

3.9 

5.6 

2.7 

9.9 

7.6 

4.8 

3.5 

3.8 

3.5 

5.1

7.8 

12.5 

10.2 

12.3 

11.3 

12.1 

12.7 

11.0 

5.7 

11.3 

5.5 

8.6 

15.7

14.7 

18.0 

10.9 

15.7 

28.0 

18.6 

9.0 

10.0

0.050- 

0.074 

mm.

10.1 

12.1 

26.3 

15.1 

18.4 

19.9 

24.8 

27.5 

27.7 

30.0

23.5 

22.7 

22.5 

23.3 

20.7 

28.0 

18.7 

21.1 

30.6 

23.3

14.4 

14.1 

22.0 

23.7 

11.2 

17.9 

18.7 

16.6 

15.3 

11.5

8.7 

15.8 

8.7 

23.8 

7.8 

7.8 

4.2 

2.7 

4.6 

2.5

6.2 

5.3 

' 15.8 

7.1 

4.8 

6.0 

7.7 

7.4 

2.9 

5.6 

2.6 

4.6 

6.9

15.8 

11.0 

9.5 

14.3 

32.4 

14.0 

6.6 

8.2

0.074- 

.119 

mm.

2.8 

17.9 

1.9 

15.3 

12.2 

14.0 

16.4 

21.7 

22.1 

27.0

23.8 

22.8 

31.0 

24.4 

37.1 

32.0 

41.9 

38.9 

26.3 

32.8

31.3 

29.2 

37.5 

34.7 

29.6 

42.9 

42.4 

43.6 

39.6 

38.2

24.7 

41.4 

45.6 

45.2 

14.4 

23.5 

13.0 

6.0 

26.0 

1.9

9.6 

4.9 

41.1 

7.0 

8.0 

7.9 

13.5 

13.5 

5.0 

6.7 

2.7 

3.1 

9.2

27.0 

9 2 

13! 8 

16.2 

12.8 

12.5 

9.2 

14.2

> 0.149 

mm.

9.8 

9.9 

7.6 

6.6 

4.6 

2.7 

3.3 

4.2 

6.4 

17.5

6.2 

6.4 

12.3 

7.3 

15.3 

8.8 

18.6 

15.9 

3.9 

9.7

39.2 

42.5 

16.5 

10.9 

45.3 

19.3 

20.7 

18.6 

17.7 

22.3

8.5 

14.6 

34.4 

11.5 

6.0 

7.7 

7.1 

5.2 

33.4 

1.7

6.9 

2.3 

8.0 

4.1 

5.9 

4.6 

5.1 

4.4 

1.0 

5.4 

.3 

.5 

7.3

5.1 

4.4 

11.0 

6.9 

1.9 

4.1 

4.9 

6.4

INDEX

Abstract___________________.. 1 

Arizona, suspended, sediment of water in. _.. 10,

25-100,141-160

Bank deposits, description of._______.. 13

Bluff, Utah, San Juan River near. _____ 9,

10,15,110-143,161-163

Cisco, Utah, Colorado River near__ 8,10,15,16-24

Colorado River, near Cisco. Utah-... 8,10,15,16-24

near Grand Canyon, Ariz_ 8,10,15,28-82,150,158

near Lees Ferry, Ariz._______ 8,15,25-27

near Topoek, Ariz_......... 9,15,87-100,148-149

near Willow Beach, Ariz.... 9,15,83-86,159-160

near Yuma, Ariz...___________ 10 

Colorado River sampler, use of_______ 2; pi. 1

Grand Canton, Ariz., Colorado River near... 8, 

 10,15,28-82,150-158

Grand Palls, Little Colorado River at... 15,144-145 

Green River, Ariz., Green River at_____ 9,

10,15,101-109 

at Green River, Ariz...------.. 9,10,15,101-109

Lees Perry, Ariz., Colorado River near_. 8,15, 25-27 

Little Colorado River at Grand Falls, Ariz... 15,

144-145

Particle size, collection of samples to determine.... 5 

Reservoir deposits, description of____ __ 13-14

San Juan River, near Bluff, Utah...__.__ 9, 

10,15,110-143,161-163

Samples, frequency of collection of.... .. 5 

individual, collection of_ .. .. 4 

integrated, collection of_ __ .... 4 

stations for collection.._ . .. 2,3

Suspended sediment, computation of concentrations of.____..__ ..... 5-6

computation of loads of._..._.. -... 6,8-9 

concentrations for daily samples of... 7,146-149 

key to tables of information on..-.. _. 15 

mean daily concentrations of -------- 6-7,16-140

mechanical analyses of._-_____----- 150-163

record of daily loads of .21-24,35-53,83-86,92-100,

106-140,144-145

relation of depth to concentration of.... 146-149

relation of mean velocity to concentration

of . 146-149

relation of to runoff,....______.__ 10

weighing of samples of._.___...__ 5

Topoek, Ariz., Colorado River near...--.-. 9, 

15,87-100,148-149

Utah, suspended sediment of water hi- -...-_. 10, 

16-24,101-143,161-163

Willow Beach, Ariz., Colorado River near... 9,

15,83-86,159-160

Yuma, Ariz., Colorado River near. 10

o

165