GEOLOGICAL SURVEY CIRCULAR. 170 

SEDIMENTATION AND CHEMICAL 

QUALITY OF WATER IN THE 

POWDER RIVER DRAINAGE BASIN 

WYOMING AND MONTANA 

By C. H. Hembree, B. R. Colby, H. A. Swenson, and J. R. Davis 

Prepared as part of a program of the 

Department of the Interior for 

Development of the 

Missouri River Basin 

UNITED STATES DEPARTMENT OF THE INTERIOR 

Oscar L. Chapman, Secretary 

GEOLOGICAL SURVEY 

W. E. Wrather, Director 

GEOLOGICAL SURVEY CIRCULAR 170 

SEDIMENTATION AND CHEMICAL QUALITY OF WATER IN THE 

POWDER RIVER DRAINAGE BASIN. 

WYOMING AND MONTANA 

By C. H. Hembree, B. R. Colby, H. A Swenson, and J. R. Davis 

Prepared as part of a program 

of the Department of the Interior for 

Development of the Missouri River Basin 

Washington, D. C., 1952. 

Free on applieation to the Geological Survey, Washington 25, D. C. 

CONTENTS 

Abstract .................... •••••••••••••••••••••••••• ••••••••••• •••••••••••••• ....•........ Introduction •••••• : ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 

Purpose and scope of investigation•••••••••••••••••••••••••••••••••••••••••••••••••••••• Previous investigations ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Personnel and acknowledgments ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Powder River drainage basin, by C. H. Hembree ••••••••••••••••••••••.••••••••••••••••.••••••••• Location and extent ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Topography •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Climate ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Soils and vegetation •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• General geology of the Powder River drainage basin, by C. H. Hembree •••••••••••••••••••••••• Exposed rocks ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• River terraces ••••••••••••••••••••••••••••••••••••••••••••••••••.•••••••••••••••••••• Physical'characteristics of the Powder River and its tributaries, by C. H. Hembr~e •••••••••• Powder River •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• South Fork Powder River ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Middle Fork Powder River •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Salt Creek •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Crazy Woman Creek .................................................................. .. Clear Creek ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Little Powder River •••••••••••••••••••••••••• ~.· ••••••••••••••••••••••••••••••••••••• Mizpah Creek •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Erosional and depositional processes in an area near the mouth of Salt Creek, 

by C • H. Hembree •••••••••••••••••••••••••••••••• ~ ••••••••••••••••••••••••••••••••••••••••• Relation of local base level to gully formation ••••••••••••••••••••••••••••••••••••••••• Runoff, by B. R. Colby •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Stream-flow records ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Distribution of runoff •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Diversions and storage for irrigation ••••••••••••••••••••••••••••••••••••••••••••••••••• Fluvial sediment, by C. H. Hembree, B. R. Colby, and J. R. Davis •••••••••••••••••••••••••••• 

Definition of terms, by B. R. ColbY••••••••••··~··•••••••••••••••••••••••••••••••••••••• 

Measurement of suspended-sediment discharge, by B. R. ColbY••••••••••••••••••••••••••••• 

Suspended-sediment records, by B. R. ~olbY•••••••••••••••••••••••••••••••••••••••••••••• 

Size composition of suspended sediment •••••••••••••••••••••••••••••••••••••••••••••• Specific weight of fluvial sediment, by C. H. Hembree, B. R. Colby, and J. R. Davis ••••• Median particle-size method ••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Size-distribution method •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 

Sediment transported as bed load, by J. R. Davis•••••••••••••••••••••••••••••••••••••••• 

Du. Boys' t:ormu.la • ...•..•••..•.••.••••••••..••••••••.•.•.•••.•.•••••.••••••.••••.•••• Schokli t s ch' s formula ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Einstein's .forDD.lla ••••...•...•.••.•••.•••.••.••••.•••.••••.••.••••..•.••..•.•••••••. 

Sediment discharged annually as bed load•••••••••••••••••••••••••••••••••••••••••••• 

Sources of sediment transported by the Powder River, by B. R. Colby ••••••••••••••••••••• Areas underlain by Paleozoic and pre-Cambrian rocks ••••••••••••••••••••••••••••••••• Areas underlain by Mesozoic rocks ••••••••••••••••••••••••••••••••••••••••••••••••••• Areas underlain by Tertiary rocks ••••••••••••••••••••••••••••••••••••••••••••••••••• Chemical quality of the water, by H. A. Swenson ••••••••••••••••••••••••••••••••••••••••••••• Plan of study •••••••••••••••••••••••••••••••••••••••••••••••••.•••••••••••••••••••••••••• Composition of river water •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Geochemistry of the basin waters ••••••••••••••••••••••••• ·• •••••••••••••••••••••••••••••• 

Chemical quality and stream discharge••••••••••••••••••••••••••••••••••••••••••••••••••• Powder River main stem •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Tributaries ••••••••••••••••••••••••••••••••••••••••••••••••••••• , ••••••••••••••••••• Chemical quality and irrigation •••••••••••••••••••••••••••••••••••••••••••••••••.•••••••• Powder River at Sussex, Wyo •••••••••••••••••••••••••••••••••••••••••••••••• ~ •••••••• 

Powder River at Arvada, Wfo••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 

Powder River near Locate, Mont •••.•••••••.•••••••••••••.•••••..•••••••••••••••••••..• Middle Fork Powder River near Kaycee, Wyo ••••••••••••••••••••••••••••••••••••••••••• 

Crazy Woman Creek near Arvada, Wfo••••••••••••••••••••••••··~··••••••••••••••••••••• 

Clear Creek near Buffalo, Wyo••••••••••••••••••••••••••••••••••••••••••••••••••••••• Clear C;eek near Arvada, Wyo •••••••••••••.•••••••••••••••••.••••••••••••••••••••••••• Chemical quality and domestic use ••••••••••••••••••••••••••••••••••••••••••••••••••••••• SUimllary of results ••••••••••••••••••••••••••••••••••••••••••••••••••••••.•••••••••••••••••••• Refer•nces •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Base data . ............•.....•...•...•...................•.•.........•...•.•......•.....•.... 

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ILLUSTRATIONS 

Powder River 2 miles downstream from mouth of Crazy Woman Creek •••••••••••••••••• Map of the Powder River drainage basin in Wyoming and Montana •••••••••••••••••••• Map of the landforms of the Powder River drainage basin and surrounding areas •••• Precipitation and runoff in the Powder River drainage basin •••••••••••••••••••••• 

Geologic map of the Powder River drainage basin in Wyoming and Montana ••••••••••• Middle Fork Powder River above the junction of Red Fork •••••••••••••••••••••••••• Sediment-filled reservoir on Salt Creek near the town of Midwest ••••••••••••••••• Aerial photograph of area near mouth of Salt Creek ••••••••••••••••••••••••••••••• Headcut of gully that joins Salt Creek near its mouth •••••••••••••••••••••••••••• Gully shown in figure'9 near confluence with Salt Creek •••••••••••••••••••••••••• Profile of gully channel. and bank from confluence with Salt Creek to headcut ••••• Map showing locations of gaging stations in the Powder River drainage basin •••••• Annual discharge, in acre-feet per square mile, for Clear Creek near Buffalo and 

the Powder River at (near) Arvada, Wyo ••••••••••••••••••••••••••••••••••••••••• Duration curve of stream flow for the Powder River at Arvada, from Oct. 1, 1917, 

to Sept. 30, 1950 ••••..•.•••••••••••••••••••••••••••••••••••••••••••••••••••••• Relation of suspended-sediment discharge to water discharge, South Fork Powder 

River near Kaycee, Wyo., May 17, 1950, to Sept. 30, 1950 ••••••••••••••••••••••• Relation of suspended-sediment discharge to water discharge, Powder River.at 

Sussex, Wyo., Mar. 1, 1950, to Sept. 30, 1950 •••••••••••••••••••••••.••••••••••• Relation of suspended-sediment discharge to water discharge, Powder River at 

Arvada, Wyo .• , Apr. 4, 1946, to Sept. 30, 1950 •••••••••••••••••••••••••••••••••• Relation of suspended-sediment discharge to water discharge, Powder River near Locate, Mont., Mar. 1, 1950, to Sept. 30, 1950 ••••••••••••••••••••••••••••••••• Relation of suspended-sediment discharge to water discharge, Middle Fork Powder 

River above Kaycee, Wyo., Apr. 22, 1949, to Sept. 30, 1950 •.•••.••••••••••••••• Relation of suspended-sediment discharge to water discharge, Middle Fork Powder 

River near Kaycee, Wyo., Mar. 1, 1950, to Sept. 30, 1950 ••••••••••••••••••••••• Relation of suspended-sediment discharge to water discharge, Crazy Woman Creek near Arvada, Wyo., Mar. 15, 1950, to Sept. 30, 1950 •••••••••••••••••••••••••••• Relation of suspended-sediment discharge to water discharge, Clear Creek near Arvada, Wyo., Mar. 21, 1950, to Sept. 30, 1950 •••••••••••.••••••••••••••••••••• Average particle-size distributions of suspended-sediment samples, Powder River 

at Arvada, Wyo ••••••.•••••••..••••••••••••.•••••••••••.•••••••••••••••••••••••• Average particle-size distributions of all suspended-sediment samples analyzed in dispersion medium ••••••••••••.•••••••••••••••••••••••••••••••••••••••••••••• Median particle size versus suspended-sediment discharge, Powder River at 

Arvada, Wyo •••••••••••••••••••• , ••••••••••••.•• , ••••••••••••••••••••••••••••••• Relation of specific weight of sediments deposited in reservoirs to median 

particle size •.•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Three cross sections of the Powder River at Arvada, Wyo •••••••••••••••••••••••••• Average of three cross sections of the Powder River at Arvada, Wyo ••••••••••••••• Bed-material size analysis, Powder River, Wyo. and Mont •••••••••••••••••••••••••• Comparison of bed-load data from the Niobrara and Middle Loup Rivers in Nebraska 

with equation qs = 2 x 104 (ys)2 •••••••••••• , ••••••.••••••••••••••••••••••••••• 

d~ 

Relation of bed-load discharge to water discharge, Powder River at Arvada, Wyo ••• Map of the Powder River drainage basin in Wyoming and Montana, showing chemical-. 

quality stations •••••••.••••••••••••••••••••••••••••••••••••••••••••••••••••••• Cumulative percentage composition of water from several streams •••••••••••••••••• Graphical analyses of water in the Powder River and tributaries •••••••••••••••••• Composition of the Powder River water at low stage, Sept. 11 to 14, 1949 ••••••••• The relation between discharge and concentration, Powder River at Sussex, Wyo., 

1949-50 •••••••••••••••••••••••••••••••••••••••••••••••••.••••••••••••• · ••••••••• The relation between discharge and concentration, Powder River at Arvada, Wyo., 

1949-50 •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• The relation between discharge and concentration, Powder River near Locate, 

Mont., 1949-50 ••.•••••••••••• ,·, ••••••••••••••••••••••••••••••••••••••••.•••••••• The relation between discharge and concentration, Middle Fork Powder River near Kaycee, Wyo., 1949-50 •••••••••.•..•••••••••••••.••••••••••••••••••••••••••••••• The relation between discharge and concentration, Crazy Woman Creek near Arvada, 

Wyo • , 19 49 -50 •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• The relation between discharge and concentration, Clear Creek near Buffalo, Wyo., 1949-50 ........................................................................ . 

Th~9~~:;~:~~-~~~~~~~-~:~~~~~~~-~~~-~~~~~~~~~~~.::~~~.:~~~~.~~~~-~~:~?~:.~:~::. Classification of water for irrigation use, Powder River drainage basin •••••••••• Minor tributary of the Middle Fork Powder River above Kaycee ••••••••••••••••••••• 

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Table 1. 

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:s. 

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s. 

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a. 

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TABLES 

Summary of exposed rock formations in the Powder River drainage basin •••••••••••• Approximate average slopes of the. Powder River and major tributaries ••••••••••••• Average discharge at gaging stations on the Powder River and its tributaries ••••• Summary of records of su~pended-s~diment discharge for the Powder River 

drainage bas in ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Median particle sizes from unweighted average size distributions of suspended 

sediment for stations in the Powder River drainage basin ••••••••••••••••••••••• Specific weight based on median particle size for the Powder River at Arvada 1 

Wyo., Oct. 1, 1946, to Sept. 30, 1950 •••••••••••••••••••.••••••• ~ •••••••••••••• Volume of suspended-sediment discharge at 56 lb per cu ft, Powder River at 

Arvada, Wyo •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Computed rates of discharge of bed-load sediment for the Powder River at Arvada, 

Wyo •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Computed annual discharge of bed-load sediment, Powder River at Arvada, Wyo •••••• Percentage composition of waters that drain from principal rock types, Powder 

River drainage bas in ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Percentage composition of water in the Powder River drainage basin during low 

flow ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Permissible limits for electrical conductivity and percentage of sodium for 

several classes of irrigation water •••••••••••••••••••••••••••••••••••••••••••• Permissible limits for boron, in parts per million, of several classes of 

irrigation water ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Monthly and annual summary of water and suspended-sediment discharge, South 

Fork Powder River near Kaycee, Wyo ••••••••••••••••••••••••••••••••••••••••••••• Monthly and annual summary of water and suspended-sediment discharge, Powder 

River at Su.asex, Wyo ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Monthly and annual summary of water and suspended-sediment discharge, Powder 

River at Arvada, Wyo ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Monthly and annual summary of water and suspended-sediment discharge, Powder 

River near Locate, Mont •••••••••••••••••••••••••••••••.••••••••••••••••••• ,. ••••• Monthly and annual summary of water and suspended-sediment discharge,·Middle 

Fork Powder River above Kaye ee, Wyo •••••••••••••••••••••••••••••••••••••••••••• Monthly and annual summary of water and suspended-sediment discharge, Middle 

Fork Powder River near Kaycee, Wyo ••••••••••••••••••••••••••••••••••••••••••••• Monthly and annual summary of water and suspended-sediment discharge, Crazy 

Woman Creek near Arvada, Wyo ••••••••••••••••••••••••••••••••••••••••••••••••••• Monthly and annual summary of water and suspended-sediment discharge, Clear 

Creek near Arvada, Wyo •••••••••••••••••• ; •••••••••••••••••••••••••••••••••••••• Particle-size analyses of suspended sediment, South Fork Powder River near Kaycee, Wyo •••••••.•••••••.••••••••••••••••••••••••••••••••••••••••••••••••••••• Particle-slze analyses of suspended sediment, Powder River at Sussex, Wyo •••••••• Particle-size analyses of suspended sediment, Powder· River at Arvada, Wyo •••••••• Particle-size analyses of suspended sediment, Powder River near Locate, Mont ••••• Particle-size analyses of suspended sediment~ Middle Fork Powder River above 

Kaycee, Wyo •••••••••••••• ·• •••••••••••••••••••••••••••••• ~ •••••••••••••••••••••• Particle-size analyses of suspended sediment, Middle Fork Powder River near Kaycee, Wyo ••••••••••••••••••••••••••••••••••••••••••••••• , •••••••••••••••••••• Particle-size analyses of suspended sediment, Crazy Woman Creek near Arvada, Wyo. Particle-size analyses of suspended sediment, Clear.Creek near Arvada, Wyo •••••••. Specific weight and median diameter of reservoir ~aiment •••••••••••••••••••••••• Particle-size analyses of sediments deposited in reservoirs, Powder River 

drainage bas in ••.•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Particle-size analyses of stream-bed material, Powder River drainage basin ••••••• Analyses of water in the Powder River drainage basin in Wyoming and Montana •••••• Powder River d~ainage basin salinity study, Sept. 10 to 14, 1949 ••••••••••••••••• 

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SEDIMENTATIONAND CHEMICAL QUALITY OF WATER IN THE 

POWDER RIVER DRAINAGE BASIN, WYOMING AND MONTANA 

ABSTRACT 

In the spring or 1946 the United States 

Geological Survey began a systematic investigation of rluvial sediments and dissolved 

minerals in streams of the Powder River drainage basin in Wyoming and Montana. This report 

gives the preliminary results that were obtained prior to October 1, 1950. As part of 

the investigation, eight sediment stations 

and seven chemical-quality stations.were opers.ted for periods of 4 months to about 4! yr,. 

A reconnaissance study was made of the geology or the area and its efrect on sedimenta~ 

tion and the chemical quality of the water. 

The rocks in the basin range in age rrom preCambrian to Recent·. Mesozoic and Tertiary rocks underlie the areas outside the moun- tains, which are also the areas of high sediment yield. 

The topography of the Powder River drainage 

basin ranges in type from rugged mountains to 

semiarid plains. The mountainous areas are underlain by pre-Cambrian and Paleozoic rocks, 

which are very resistant to erosion. Most of 

the drainage basin is a part of the Great 

Plains province. Precipitation is low over the plains, and most of the runoff is in direct response to storms. Practically all 

streams rising in the plains are ephemeral or intermittent. Rocks underlying the plains areas are mostly erodible shales, siltstones, 

and sandstones; and the stream valleys have 

alluvial fills that are susceptible to ero- ·sion. 

Average annual runoff varies rrom .less than 

1 in. ove~ most of the plains area to more than 15 in. near the crest of the Bighorn Mountains. Most of the flow of the Powder 

River originates in the mountains. The moun- tain streams are clear and have steep gradients. Streams in the plains have low gradients and usually flow in sandy-bottomed, shifting channels. 

Since April 4, ·19·46, records of suspendedsediment discharge have been obtained at 

Arvada, Wyo. Similar records have been obtained at the gaging.station on the Middle 

Fork Ppwder River above Kaycee since April 22, 

1949, 'nd at six other gaging stations in the 

Powder River drainage basin since the spring 

of 1950. The average annual discharge or sus- pended sediment at the Arvada station ror the 

period of record was about 5,500,000 tons, 

and the average annual water disc~arge was about 200,000 acre-ft, which is only twothirds or the average annual discharge ror the period of stream-flow records at Arvada. 

The concentrations and discharges of suspended 

sed"iment were low at gaging stations on Clear 

Creek near Arvada, Crazy Woman Creek near Arvada, and the Middle Fork Powder River 

above Kaycee. Most of the water that passes 

these stations comes from the mountains; much or this water is melted snow. Records of sus- pended-sediment discharge obtained at sediment stations during the water year 1949-50 are not representative because the water discharge ror that year was nearly as low as the 

lowest annual discharge for the period that 

is covered by stream-flow records. 

The study shows that the mountain area·s have relatively high runoff and are minor sources of sediment. In contrast, the plains areas have low runoff and are major sources of sediment. The effects of fairly rapid ero- sion can be seen in most of the plains areas, 

but more rapid rates of erosion probably oc- cur in badland areas, at gullies that are ac- tively eroding, and on the outside edge of 

stream meanders. Erosion of alluvium from the 

valleys or main streams probably supplies 

much of the sediment that is transported by the Powder River. 

The specific weight or a sediment deposit 

that might be formed from the suspended sediment of the Powder River at Arvada, Wyo., was computed .to be 56 lb per cu ft when the deposit has not been compacted during a period or many years or under the weight of appreci- able quantities or overlying deposits. This 

specific weight was based on the particlesize analyses of suspended-sediment samples from the Powder River at Arvada and on the 

relation between median particle size and 

specific weight of sediment deposits in res- ervoirs. From April 4, 1946, to September 30, 

1950, the measured suspended-sediment discharge at Arvada was 26,146,000 tons. The initial volume of this quantity of suspended 

sediment arter deposition at 56 lb per cu ft 

would be 21,420 acre-ft. 

Three difrerent equations were applied to 

compute discharge of sediment as bed load for 

the Powder River at Arvada. Results based on two or the equations were used to compute an- nual bed-load discharges of 190,000 tons and 

160,000 tons at Arvada. 

The chemical quality of the water in the 

Powder River drainage basin difrers.widely 

from one stream to another and is variable in 

each stream from headwaters to mouth. Geologic factors largely determine the nature and 

the amounts of dissolved solids that are transported by the Powder River and its tributarles. In mountainous regions that are un- derlain by igneous rocks of pre-Cambrian age the river water is dilute, and the mineral 

1 
2 

content is composed mainly of calcium and 

carbonate; the concentration of dissolved 

solids for a water from this source is often 

less than 100 ppm. Where the Powder River 

drains an area of erodible shales and sandstones of Tertiary and Mesozoic age, the riv- er water is much more concentrated, and the 

mineral content consists largely of sodium 

and sulfate. The concentration of soluble 

salts in this water sometimes exceeds 2,000 

ppm. The chemical pattern of water in tributary streams varies from headwaters to mouth 

owing to geologic factors or to cultural influences, such as return irrigation flows. 

The chemical analyses of over 100 water 

samples that were collected from three stations on the Powder River and from four stations on tributary streams during the period 

November 1945 to September 1950 show the quality of the water under varying conditions of 

flow. The periods of higher salt concentrations corresponded approximately with intervals of low water discharge, whereas days of 

lower salt concentrations were associated 

with days of high runoff. A basin salinity study of low flows established a salinitydischarge relationship for important streams 

in the basin. 

As a source of irrigation supplies, the 

main stem waters at Arvada are rated, on the 

average, as permissible, as defined by 

Wilcox's classification of irrigation waters. 

Of 27 samples of water that were collected at 

Arvada during discharges of 1.5 to 2,110 cfs, 

1 was rated as good, 17 as permissible, and 9 as doubtful for irrigation. The waters in 

tributary streams, in general, are of better 

quality. 

The main stem waters contain objectionable 

amounts of dissolved minerals for ordinary domestic uses, whereas the tributary waters 

are, as a rule, of more satisfactory quality. 

INTRODUCTION 

Purpose and Scope of Investigation 

The investigation of sedimentation and of 

_the chemical quality of surface wat~rs in the 

Powder Riv~r drainage basin was undertaken as -a part· of the program of the Department of 

the Interior for development of the Missouri 

River basin. The over-all plan for the basin 

includes the development of irrigation and 

hydroelectric power and the storage and regulation of flood waters. One of the requirements for successful planning of economically feasible projects in the basin is reliable informatio~ on fluvial sediments and on the 

chemical quality of the water. 

The study of sedimentation in the.Powder 

River drainage basin was begun to determine 

the quantity of sediment that is transported 

by the Powder River and its major tributaries, 

the prob~ble specific weight of the sediment 

deposit as initially laid down in a reservoir, 

and the probable sources of sediment. This 

progress report summarizes the results to 

September 30, 1950. 

On April 4, 1946, the Geological Survey in- stall~ a sediment station on the Powder 

River at Arvada, Wyo. Since that time seven additional sediment stations have been established on the Powder River and tributaries. 

The stations and the dates on which the-collection of samples was begun are as follows: 

South Fork Powder River near Kaycee, Wyo ••••••••••••••• Powder River at Sussex, Wyo • Powder River at Arvada, Wyo. 

Powder River near Locate, 

Mont •••••••••••••• ~ ••••••• Middle Fork Powder River 

above Kaycee, Wyo .•••••••• Middle Fork Powder River near Kaycee, Wyo •••••••••• Crazy Woman Creek near Arvada, Wyo ••••••••••••••• Clear Creek near Arvada, 

Wyo •.•••.••••••••••••••••• 

May 17, +950 

.March 3, 1950 

April 4, 1946 

March 3, 1950 

April 22, 1949 

March 3, 1950 

March 2, 1950 

March 2, 1950 

The records of suspended-sediment discharge for the Powder River at Arvada, Wyo., were .supplemented by computed rates of sediment 

that is discharged as bed load. 

Sediment discharge data collected at these 

stations for a sufficient period of time will 

give a measure of the probable quantity of 

sediment that will be transported by the 

streams over a long-term period. Size analy- ses of suspended-sediment samples, together with analyses of bed-material samples, will 

furnish data for computing the probable initial specific weight of the suspended sediment after deposition in a reservoir. 

The network of sediment stations is arrang- ed so that a comparison of the sediment loads 

measured at the stations will show the general areas where sediment yield is high. P~e­

.liminary field studies have been made to se- lect the specific areas and the types of ero- sion that contribute most of the sediment to 

the Powder River. More ~ntensive studies 

should be made before engineering works that are designed to reduce sediment yield are started. 

In this study of the chemical quality of 

waters in the Powder River drainage basin the 

following four items were considered: the 

geochemistry of the basin waters, the quality 

of the water in relation to stream discharge, the rating or classification of these waters 

for irrigation, and the use of the waters for 

domestic needs. Of these items, the classification of the basin waters as to their suitability for irrigation was given the most attention inasmuch as this information has a direct bearing on further agricultural development of the basin. 

.Seven sampling stations for chemical-qual.-

ity studies were established on the Powder 

River and key tributaries in the period from 

1945 to 1949 to determine the quality of 

water. Stations on the Powder River were operated at Sussex, Wyo., at Arvada, Wyo., and near Locate, Mont. Stations maintained on tributaries were the Middle Fork Powder River near Kaycee, Crazy Woman Creek near Arvada, 

Clear Creek near Buffalo, and Clear Creek near Arvada, all in Wyoming. The stations on the Powder River .furnish information on the 

change in the qu.ali ty of the water in the 

river from headwaters to the mouth. The station near Locate measures the quality of the 

water that leaves the basin. Tributary stations except Clear Creek near Buffalo were established at points near the mouths of 

these tributaries. 
A salinity study was made September 10 to 

14, 1949, to determine the chemical character 

of the water in the basin during a period of 

low flow. 

The geologic studies made during the investigation provide a background of information 

that is essential to the understanding and 

·interpretation of the base data, both on sediment and chemical quality. The material .car- ried by the streams in solution, in suspension, and as bed load was originally derived 

from the rocks in the basin. The geologic 

studies, therefore, included a review of pertinent published reports and a reconnaissance 

of the basin to study the rocks and their re- lationship to the sediment and minerals that are carried in suspension and in solution by 

the streams. 

Previous Investigations 

In 1938 the Corps of Engineers, U. S. Army, 

started a study of suspended sediments in the 

Powder River and its tributaries. This study 

continued through 1944, and some of the re- sults of the study are contained in Supplement VI of a report on the Yellowstone River 

and tributaries by the office of the Corps of 

Engineers (U. S. Army, 1946, pp. T6 and Tl2a) 

at Fort Peck, Mont. The sediment stations and 

their periods of operation are as follows: 

Powder River at Arvada, Wyo. May to June 

1938 

Powder River at Moorhead, 

Mont .•••••••••••••••••.•••• April 1938 to 

April 1946 

Middle Fork Powder River near Kaycee, Wyo •••••••••• May 1938 to 

January 19 40 

South Fork Powder River near Kaycee, Wyo •••••••••• May 1938 to 

March 1940 

Clear Creek at Buffalo, Wyo. April 1938 to 

March 1939 

Many reports on the geology of the Powder 

River basin have been published, but most of 

them have been concerned primarily with oil 

and gas resources. So far as is known, geology has not been used to help in s9lving the 

sedimentation and quality-of-water problems 

of the area. 

Personnel and Acknowledgments 

This investigation is one of several being 

made by the U. S. Geological Survey in co- operation with other agencies of the Department of the Interior. The investigation was conducted by the Water Resources Division of 

the Geological Survey, C. G. Paulsen, chief 

hydraulic engineer, and S. K. Love, Chief of 

the Quality of Water Branch, Washington, 

D. C., and was under the general supervision 

·of P. C. Benedict, regional engineer, Lincoln, 

Nebr. 

Th~ analytical work on the chemical quality 

of surface waters was supervised by H. A. 

Swenson, assisted by personnel of the office 

at Lincoln~ Nebr. 

Records of suspended sediment were obtained 

by personnel of the office at Worland, Wyo., 

under the supervision of T. F. Hanly. 

3 

Unpublished records of water discharge were furnished by F. M. Bell, district engineer, 

Geological Survey, Denver, Colo., and Frank 

Stermitz, district engineer, Geological Survey, Helena, Mont. 

POWDER RIVER DRAINAGE BASIN 

Location and Extent 

The Powder River and its tributaries drain an area of about ·13,400 sq mi (Congressional 

documents, 1934, p. 26) in northeastern 

Wyoming and southeastern Montana. More than 

half of the drainage basin is in Wyoming. The 

Powder River drainage basin is bounded on the 

southwest by the Bighorn Mountains. The rest 

of the boundary is formed by low divides that 

separate the basin from the drainage basins 

of the Tongue, Little Missouri, Belle Fourche, 

Cheyenne, North Platte, and Bighorn Rivers. 

The South Fork, largest tributary of the 

Powder River, rises in the Rattlesnake Range near Ervay, Wyo., and flows northeastward to 

its junction with the Middle Fbrk a few miles 

east of Kaycee, Wyo. The Powder River, formed 

by the junction of the South and Middle Forks, 

flows eastward to a point a short distance 

downstream from Sussex, Wyo., where it turns 

abruptly and flow~ northeastward into an alluvial valley bordered by badlands (fig. 1) 

to join the Yellowstone River near Terry, 

Mont. The Powder River, including the South 

Fork, is about 480 miles long (Congressional 

documents, 1934, p. 26). 

The principal tributary streams entering 

the Powder River downstream from Sussex are Crazy Woman Creek, Clear Creek, the Little 

Powder River, and Mizpah Creek. (See fig. 2.). 

All these streams except the Little Powder 

River drain areas to the west of the Powder 

River. 

Topography 

The topography of the Powder River drainage 

basin ranges from rugged mountains. to semiarid plains. (See fig. 3.) Mountains, plateaus, uplands, lowlands, badlands, and river 

terraces form the varied landscape of the 

basin. 

Except for a very small area drained by the 

Tongue River, the east slope of the Bighorn 

Mountains in Johnson and Natrona Counties, 

Wyo., is drained by streams tributary to the 

Powder River. The altitude of the Bighorn 

Mountains ranges from about 9,000 ft on the 

south to 13,165 ft at the top of Cloud Peak near the northwest corner of Johnson County. 

Cloud Peak is the culmination of a rugged area of granite ridges and glacial cirques in 

the high central part of the Bighorn Mountains. Most of the cirques are now free of . ice, but a few at the base of Cloud Peak still 

contain remnants of once large mountain glaciers. The erosive action of the mountain 

glaciers--large· rivers of moving ice--is evident on most of the topographic features of 

the central area. 

The south part of the Bighorn Mountains is an extensive plateau dissected by deep streamcut'canyons. The plateau, built on the sedimentary rocks that arch over the crest of the 
~ 

Figure 1,--Powder River 2 miles downstream from mouth of Crazy Woman Creek. This is a ttpical section of the river valley 

upstream from the mouth of Clear Creek. Note the flood plain and the higher terraces. At this point the flood plain is 

about 5 ft above the stream, and the next terrace is about 12 ft above the stream. A gravel-capped terrace can be seen through the opening in the trees on the right and about 50 ft above the stream. Note the cut banks and wide flat stream 

bed. 
1\J I 

EXPLANATION 

® 

Quality of water station 

Sediment' • station 

Sediment and :ltemicol quality 

of water station 

aLp"-' ..&.• ..I.'..&I.JY~-.._-~. __ ....._ _ ___.3p Miles 

0 SHERIOAN 

I 

J 

I 

\..... rJ-) J 

_,:_./ ....... 0 GIIIelfe 

0 Ekoloko · 

44• r------..!.W!...,· __ ~-4---+-~-~=.:::...J!!!--~(t--__!_ ___ ....!.N.!f---~G!!--___ "--"144. 

0 CASPER 

Index mop of Montono and .wyoming 

•howif~Q the Powder R!ver drainage basin 

Figure 2.--Map of the Powder River drainage basin in Wyoming and Montana. 
10 0 ,, Ill I eo Miles I 

Figure 3.--Map of the landfor.ms of the Powder River drainage basin and 

surrounding areas • 
mountains, is an area or forests and associated parks. 

- The front range, which stands about 2,000 

ft above the plains and extends along the 

east side of the mountains, is a large hogback of plainward-dipping-sedimentary rocks. 

The west side or the front range is a rather 

abrupt slope or clirf. 

A westward-facing cliff of red rock, called 

the red wall, runs along the south and south- ~ast flank of the Bighorn Mountains from a point north of Barnum southward to the head 

of Burfalo Creek. The red wall is a hogback 

of eastward-dipping red siltstone strata and, 

because of its color, is the most striking of t~e many hogbacks along the east side of the 

mountains. 

The greater part of the Powder River drainage basin lies to the east of the mountains 

and is a part of the Great Plains province. 

In this area the rolling uplands are at a much higher elevation than the main streams. 

Parts of the uplands are level and receive 

sufficient precipitation for dry farming, but 

most of the uplands are used for grazing, ow- ing to a lack of precipitation and to the 

sloping topography. 

Probably the most distinctive type of topography in the drainage basin is the badlands, 

which form a border around the uplands and 

usually separate them from the lowlands along 

the rivers. However, at some places the badlands ext·end to the banks of the streams. Although they may be only narrow bands, in some places they are an almost impass'able area· of 

sharp ridges and steep canyons that extend 

several miles back from the streams. 

Climate 

The Powder River basin, owing to the range 

in altitude from about 2,300 ft to more than 

13,000 ft, has wide local differences in temperature and precipitation. These differences 

in climate not only affect the amount of sediment that is transported by the streams but 

also partly determine the areas that will furnish most of the sediment to the streams. 

As shown by figure 4, relatively heavy pre- cipitation, most of which is snow, occurs in 

the high mountal.ns. Climatological records are not available at high altitudes, but precipitation at some localities in the moun- tains probably exceeds 30 in. a year. The 

lines of average annual runoff in figure 4 

give an indication of the increase in precip- itation with altitude. 

The climate of the lower mountain slopes 

and foothills is less humid, but the climate 

does vary in the foothill belt because of 

differences in altitude and topographic features. The foothill section, in general, is a transitional zone between the cold, humid 

climate of the high mountains and the relatively warmer and more arid climate o~ the 

plains. 

The. climate of the rest of the bas in is, in 

general, one of less precipitation and of 

greater variation in temperatures. The plains 

section has a semiarid climate with an aver- age precipitation less than 15 in. annually. 

Soils and Vegetation 

The soils of the Powder River drainage basin are represented by a large number of 

broad soil groups, which follow vegetational 

and climatic differences without regard to 

geological conditions (Thorp, 1939, p. 42). 

They are: soils of the humid mountains, 

7 

soils of the subhumid foothills, and soils of 

the semiarid plains. Only small areas of soil were developed over many of the rock formations of the mountains. In the higher part of 

the mountains the soils, where they occur, are well-developed Podzols. The soils in the 

foothills and semiarid plains are mainly 

Chernozem and Chestnut soils, but possibly 

the soils of the more arid part of the plains 

may be grouped with the Brown soils (Dunnewald 

and others, 1939, p. 32). The Chernozems are mainly restricted to narrow areas in the foothills. 

The soils of the older terraces and alluvial 

fans have a dark grayish-brown surface layer, a very heavy brown gumbo upper subsoil layer, 

and a thick accumulation of silty lime in the 

alluvial substratum. Alluvial gravel from 

many types of rocks is present at different 

depths. 

The soils of the younger terraces and alluvial fans range in color from light grayishbrown to black, have little clay or gumbo in 

the upper subsoil layers, and have only a moderate accumulation of lime in the subsoil. 

In most areas these soils are underlain by a series of old buried soils, which are exposed 

in many places in high stream banks and road 

cuts. 

The soils or the flood plains are composed 

of water-deposited silts, sands, clays, and 

gravels; all are more or less calcareous. 

Near the mountains the soils are dark or have a pink tinge, owing to organic material or fragments of parent rocks. The farther the 

soils lie from the mountains, the more uniform is their pale-gray color. 

The soils of the uplands in the plains area are mostly shallow, and their color and texture are due to the character of the parent ma~erials. The surface color of the soils is 

gray, grayish-brown, or reddish-brown. The 

surface soils are sandy, silty-clay, or clay 

loams. 

In the open areas of the mountains the soils are dark brown and black, and the surface 

soils are usually about 1 ft thick. The color 

of the subsoil depends upon the parent rock. 

In the forested areas under a thin layer of 

partly decomposed pine needles, the soil is 

light grayish-brown loam to a depth of 3 or 4 

in. Below this layer the soil is lighter-colored. 

The native vegetation of the Powder River 

basin is as varied as the soils. Large areas in the mountains are covered by forests. The 

most common tree is the lodgepole pine, but 

the western yellow pine, limber pine, Engel- mann spruce, alpine fir, red cedar, and aspen are common. Willows grow in some of the mead- ows along the streams. The open areas in the 

forests are covered with many kinds of pasture grasses. 

The vegetation of the semiarid plains is a typical arid-land cover of grasses, sagebrush, 
EX PLANATION 

• U.S. Weather Bureau station 

(8,821) 

AI titude, in feet 

27.10 

Average a.n nua I r a i nfa II, 

in ·inches 

---0.5---

Average annual runoff, 

in inches 

Powder 

25 

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

River basin 

0 

I I I I I I 

q~ 

~\ 

\ 

\ 

\ 

.II) 

o· 

I I 

I I 

I 

Figure 4.--Precipitation and runorr in the Powder River drainage basin. Lines or average annual runorr from u.s.G.s. Circular 37. 

8 
pricklypear, and rabbitbrush. The most common grasses are gramagrass, wheat grass, junegrass, 

and buffalograss. Greasewood is common on s&l·}-impregnated soils. Cottonwoods grow 

along some of the streams, especially the 

Powder River. Near the mountains where sufficient moisture is available, there are dense 

thickets of plum, chokecherry, haw, and other 

bushes. 

GENERAL GEOLOGY OF THE POWDER RIVER DRAINAGE 

BASIN 

Exposed Rocks 

The rocks exposed in the Powder River 

drainage basin are granite and schist of preCambrian age and a thick series of sedimentary strata·that range in age from Cambrian 

to Recent. (See table 1.) Outcrops of preCambrian and Paleozoic rocks are confined to areas in or near the mountains. The rocks of 

pre-Cambrian age are igneous and metamorphic 

and erode slowly. These of Paleozoic age are mostly limes.tones and sandstones· that are relatively resist~nt to erosion. 

Rocks of Mesozoic age crop out principally 

along the.east flank of the Bighorn Mountains 

and over large areas in the southwest part of 

the basin (fig. 5). On the basis of different 

erosional characteristics, the sedimentary 

rocks of the Mesozoic era may be divide9, in 

general, into three groups. The first group, comprised of the Triassic and Jurassic formations and the Cretaceous Cloverly formation, 

has a small area of outcrop and is not an important source of sediment even though some of the format1ons are highly erodible. The 

seeond group, made up of the Thermopolis and 

Mowry shales, the Frontier formation, and the 

9 

Cody shale, is composed of a great thickness 

of alternating thin beds of sandstone and 

thick beds of highly erodible shale. The 

third group, comprised of the Mesaverde, 

Lewis (or Bearpaw), Foxhills, Lance (or Hell 

Creek) formations, is a aeries of interbedded 

sandstones and shales. Except for local areas, 

such as the headwaters of Salt Creek, this 

group is considered to be a minor source of 

sediment because of its relatively small ar~a 

of outcrop, even though some of the beds of 

shale and sandstone erode rapidly. 

Rocks of Cenozoic age cover the greater 

part of the plains section of the basin north 

of Sussex. (See fig. 5.) Those of Paleocene 

and Eocene age consist of sandstone, shale, 

sil.tstone, and some coal. Part of the terrain 

underlain by these rocks is rolling, and ero- sion appears to be at moderate rates. The un- equal resistance to erosion of the finetextured materials and the sandstones has 

caused the formation of steep broken topography along many of the interstream divides 

and of badlands along the streams. Small 

patches of rocks younger than Eocene and oid- er than the Recent alluvial deposits occur in 

and adjacent to the mountains, but, because 

of the small area of outcrop, they are not 

significant as a source of sediment. 

River Terraces 

A knowledge of the history of river ter- races in the Powder River drainage basin is 

essential to an understanding of the causes of past and present rates of erosion and deposition. Although some preliminary field work 

has been done, additional information still 

is needed before a satisfactory discussion of 

the river terraces can be prepared. 

Table !.--Summary of exposed rock formations in the Powder River drainage basin (Darton, 1906, 

pl. 47; Hares and others, 1946; Love, 1945; Thompson, 1949; Brown, 1949; Wegemann, 1918, p. 13; 

Reeside, 1944; Thomas, 1948, pp. 79-92; Love and Weitz, 1951) 

Age Formation and member Remarks 

Glacial deposits in the mountains. Terrace and floodQuaternary plain deposits of gravel, sand, and silt along the 

Unconformity. streams. 

White River(?) formation 

Oligocene and younger unnamed Sands, volcanic ash, gravels, and boulders. 

rocks. UncoJtrt· Sandstone, drab-colored; drab-colored to variegated 

~ Moncrief member claystone and shale; and numerous coal beds. MonEocene ..c:~ crief member consisting of conglomerate of _preI» oa Cambrian rock fragments, sandstone, and drab shale. s:.. .Ps:.. . Kingsbury member consisting of conglomerate of Cll Clio ~ : ~ Kingsbury member Paleozoic rock fragments, sandstone, and variegated .p 

s:.. ill: . claystone. Q) Uriconformit., E-4 ~ Tongue River Sandstone, light-colored, massive; drab-colored shale; §~ member and numerous coal beds. On the east side of the 

Paleocene ~.p Powder River basin the Fort Union is, in places, :§~ Lebo member divided into three members: the Tongue River mem- .PS:.. ber at the top, the Lebo member in the middle, and 

8c8 Tullock member the Tullock member at the base. 1%.. 

Unconformit., 

Lance Hell Creek Sequenc~ of dark marine shales (Lewis, Bearpaw), folformation formation lowed by marine sandstone (Fox Hills), and then by 

Cretaceous Fox Hills Fox Hills nonmarine dark-colored claystone and shale and coal 

sandstone sandstone beds called Lance in Wyoming part of basin, except 

Lewis Bearpaw near Black Hills, and in Montana part of basin, 

shale shale where Hell Creek formation is used. 
10 

Table 1. --Summary of exposed roc.k formations in the Powder River drainage basin--Continued 

Age Formation and member Remarks 

~ Teapot sandstone 

G>...t 0 member 

'O.j.ll Sandstone, alternating white to buff, massive, cross-

~~ beddedJ coal-bearing, with a middle zone of marine 1:-~ shales. In northern part of basin Teapot member is CltO 

Cll4M Parkman sandstone not recognized. Q) 

:II member 

G) 

..... Shannon sandstone Sandstone, shaly; dark-gray marine shales; calcareous Cit I»..C: member shale; thin limestones; and a few thin beds of 

'OCQ bentonite. 0 

0 

Cretaceous 

~· Wall Creek sandstone G>Cit member Sandstone and shales, interbedded, gray and black. ...tEl~ 

.j.l!M0 Thin sub-bituminous coal beds are present. ~O...t 

0Ci-f.j.ll 

t 

Mowry and Thermopolis Mowry shale, hard, black, si~iceous, weathers silvery 

gray; underlain by soft black Thermopolis shale shales, undivided that has Muddy sandstone member 200 ft above base. 

Inyan Kara group includes Fall River sandstone at 

Inyan Kara group and top, Fuson shale in middle, and Lakota sandstone at 

Cloverly, Morrison, and base along eastern margin of Powder River basin; 

Unkpapa formations, un- Cloverly formation used along southern and western 

divided margins. Morrison formation consists of green to variegat~d claystone and thin limestones in Black 

Hills. 

Jurassic In descending order, green glauconitic shale, red 

sandstone and siltstone, gray sandstone, green Sundance and Gypsum Spring shale, and lenticular white sandstone. At base is 

formations, undivided Gypsum Spring formation consisting of red siltstone and gypsum with some white dolomite and limeUnconformity. stone beds. 

~ Popo Agie member Claystone, ocher-colored; purple to red siltstone; 0 M...t and limestone conglomerates. Q).j.ll 

-+Jed Alcova limestone 

Triassic CIS ~ member Limestone, thin, crinkly light-gray. 

t,o .a Ci-t Red Peak member Siltstone, reddish. 0 

Unconformity(?) Undivided Triassic and Permian rocks along the south 

Permian and west margins of the Powder River basin. 

Unconformity 

CQ Pennsyl- Tensleep sandstone and Sandstone, thick; unde~lain by red shale and lime- ::s van ian Amsd~n formation, 0 stone and red to gray sandstone. M undivided Q) 

Ci-t 

.... -Unconformity s:: 

0 Miss is- Limestone and dolomite, massive, blue-gray, cherty • .0 

1:.1 sippian Madison formation Locally includes dolomite and sandstone of CIS 

0 Devonian { ? ) age. 

Unconformity 

Ordovician Bighorn dolomite underlain by equivalents of Flathead 

Unconformity. sandstone and Gros Ventre and Gallatin formations 

Cambrian along west margin of Powder River basin. 

nnconformity. 

Pre-Cambrian Granite, schist, and gneiss. 
••• 

EXPLANATION 

streams Alluvium 

mountain ond along flanks 

} QUATERNARY l 

fL1a CENOZOIC 

Limestone, sonelstone,}TERTIARY 

shale, convlomerote, onel tuff 

Limest!f:~Cistone,} MESOZOIC shale, siltstone, onel gypsum 

Limestone ~} sandstone PALEOZOIC shale, ond dolomite' · 

• } PRE-CAMBRIAN Gronote, gneoss, and · schist 

Geology otter U.S. G. S. Geologic mop of Wyoming, 

1925, U.S. G. S., Oil ond Gas Invest., Prelim. mop 

51, 1946, and U.S G. S. Prelim. Mop of Paleocene 

of the Rocky Mountaons ond Plains, 1949. 

10 0 40Miles 

0 SHERIOAN 

.•. r-----w=-----

oCASPER 

WYOMING 

sltowint 

lftdtx 

the 

map Powder of Montana 

River 

oncl 

di'oinott 

~ 

baSin 

Figure 5.--Geologic map of the Powder River drainage basin in Wyoming and Montana. 
12 

PHYSICAL CHARACTERISTICS OF THE POWDER RIVER ~ND ITS TRIBUTARIES 

The physical characteristics of a stream are controlled by many factors. Outstanding 

among the factors are types of rock material, 

climate, topography, and vegetation. Although the factors are interdependent, types of rock 

material and climate play the leading role in 

determining the characteristics of a stream; 

type and density of vegetation as well as 

minor topographic features are dependent upon 

them. In describing the characteristics of 

the streams, only types of material and topography associated with the streams will be discussed. Climate and vegetation have been described in previous parts of this report. 

The approximate slopes, differences in altitude divided by lengths of channel, of the 

Powder River and its tributaries are listed 

in the following table: 

Table 2.--Approximate average slopes of the Powder River and major tributaries 

Approximate slope 

Rivers and selected reaches in feet per mile 

South Fork Powder River. • • . • • • • • • . • • • • • • • • • . • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 10 

Powder River from junction of the Middle and South Forks to mouth............... 7 

Middle Fork Powder River 

From headwaters to mouth of Red Fork •••••••••••••••••••••••••••••••••••••••• 110 

From mouth of Red Fork to junction with the South Fork ••.•••.••••••••••••••• 9 

Buffalo Creek •.....••.•.•••••••••.••••••••••••••••••••.••••••••••••.•••••• Beaver Creek .•......••••••••.•.••••••.••••••••••••••••••••••..••••..•••••• Red Fork ....••...••••••....•••••...•••••••••••.••••••••••••••.••.••••••••• 

90 

140 

110 

North Fork Powder River 

From headwaters to Mayoworth ••...••••••••.•••.•..•••••••••••..•••••••••• From Mayoworth to mouth •••..•••••••••••••••••••••••••••••••.•••••••••••• Salt Creek from Midwest to mouth •.•.••.••••••••••••••••••••••••••••••••••••••• 

110 

30 

10 

Crazy Woman Creek 

From headwaters to junction of the North and Middle Forks ••••••••••••••••••• From junction of the North and Middle Forks to mouth •••••••••••••••.•••••••• Clear Creek 

150 

10 

From headwaters to mouth of Rock Creek .•••.••••••••••••••••••••••••••••••.•• 220 

13 

7 

8 

From mouth of Rock Creek to junction with the Powder River ••••••.•••••••••••• Little Powder River .•••.••••••••••••••••••••••••••••••.••••••••••.•••••••••••• Mizpah Creek ..••••....•••••.•...•••••••••.•••••••••••••••••••••••••••••••••••• 

Powder River 

The Powder River is formed by the junction of its Middle and South Forks, 2 miles downstream from the junction of the Middle and 

North Forks and 6 miles east of Kaycee, Wyo .. Above their junction the three Forks drain an area of about 2,220 sq mi (Follansbee, 1923, 

p. 101). The Powder River, therefore, is from 

its inception a large river. However, it is 

merely an extension of the South Fork in that 

it has all the characteristics of that stream 

and 'practically none of the characteristics 

of the Middle Fork. The Powder River, then, 

begins as a wide, flat, meandering stream 

that flows on a sand-covered stream bed between predominantly low stream banks. Throughout most of its length, it is bordered by a wide, low flood plain and a series of ter- races that blend into alluvial fans that ex- tend down from the bordering hills. (See 

fig. 1.) At some poipts, where the river is 

cutting laterally into flood-plain deposits 

that predate the presen~ flood plain, the low 

stream banks give way on oae side to high banks. 

Except for the alluvium of the flood plain 

and terraces, the valley of the Powder River 

is underlain, for the most part, by sandstones, siltstones, and shales of the Fort 

Union and Wasatch formations of Tertiary age. 

Similar badland topography is developed from 

both ~ormations. However, badlands developed 

from the Wasatch formation are more extensive, 

but this is probably due to geographical location rather than to any major difference in 

the erodibility of the two formations. 

Northward from Sussex the difference in altitude between the valley floor and the highlands increases and reaches a maximum about 

half way between Sussex and Arvada. Badland 

topography increases with the increase in re- lief and reaches maximum development along 

the river east of Buffalo. Here the badlands 

extend several miles back from the river, but 

they gradually become more subdued downstream. 

During July, August, and September there is 

little or no flow in the Powder River between 

Sussex and the junction of Clear Creek. Consequently, during these months almost all sediment carried into the Powder River by tributaries upstream from Clear Creek is deposited 

in the channel. Part of this channel fill is 

moved downstream by spring floods and is re- placed later by material transported from upstream. For many miles below its junction 

with the Powder River, the summer flow of 

Clear Creek, a stream which carries little 

sediment, flushes from the channel of the 

Powder River the finer sediments that are deposited during spring floods. 

The flow of Powder River is maintained almost entirely by tributary streams from the 

Bighorn Mountains to the west. The Little 

Powder River is the only major tributary to 

the Powder River from the east. 

South Fork Powder River 

The South Fork Powder River rises in the 

Rattlesnake Range near Ervay, Wyo., in the 

extreme western part of Natrona County and 

flows northeastward to its junction with the 

Middle Fork, 6 miles east of Kaycee. East of 

the Rattlesnake Range the South Fork flows 

through an area of high rolling plains, which are deeply trenched by tributary streams. The 

headwaters of the tributari streams are separated by low divides from the headwaters of 
streams tributary to the Bighorn .and North 

Platte Rivers. Wallace, Cave, and Willow 

Creeks are the major tributaries to the South 

Fork. 

The South Fork flows across many kinds of 

rocks, but about three-fourths of its drainage area is underlain by shales of Cretaceous 

age. 

For most of its length the South Fork flows 

in a wide valley that is flanked by low 

rounded hills. Leading down from the hills are valleys, which i~ the past were cut by 

streams and partly refilled with alluvium. 

Many of these valleys are now the sites of 

deep gullies, which carry large volumes of 

sediment-laden water into the South Fork during and following heavy rains. 

Easily eroded material, sloping land, 

sparse vegetation, and rainfall of high intensity combine to make the South Fork one of 

the major contributors of sediment to the 

Powder River. 

Middle Fork Powder River 

The Middle Fork Powder River originates in 

the southern part of the Bighorn Mountains 

and flows northeastward to its junction with 

the South Fork east of Kaycee. All its major 

tributaries except Buffalo Creek rise in the 

mountains and have characteristics of moun- tain streams for most of their length. In the 

mountains they flow over stream beds of gravel or boulders and carry very small quantities of suspended sediment. At the foot of 

the mountains they leave the areas underlain 

by Paleozoic rocks and flow across areas un- derlain by the more erodible Mesozoic. rocks 

where their gradient decreases and where they 

begin to acquire some of the characteristics 

of sediment-carrying s_treams. (See fig. ·s.) 

Important perennial tributaries of the Middle 

Fork are Buffalo Creek, Beaver Creek, Red 

Fork, and the North Fork Powder River. In the 

spring and summer most of the flow of these 

streams is diverted f.or irrigation. 

Salt Creek 

Salt Creek and its principal tributaries 

rise to the south of the town of Midwest and 

drain an area underlain principally by Cretaceous shales. "It flows in a general northwestward direction to join the Powder River near Sussex. It has a total drainage area of 

about 840 sq mi (Follansbee, 1923, p. 101). 

Along Salt Creek and some of its tributaries, 

especially in the lower reaches, there are broad alluvial flood plains and.high cut 

banks, but the land back from these major 

streams is cut into extensive areas of badlands b¥ a network of deep gullies. (See 

fig. 7.) During the summer the creek flows 

only in rainy weather. After heavy storms it 

becomes a large and heavily sediment-laden 

river. Salt Creek, like the South Fork Powder 

River, is potentially one of the largest sediment-contributing streams in the Powder 

River drainage basin. 

Crazy Woman Creek 

The tributary forks of Crazy Woman Creek 

rise in pre-Cambrian granites near Hazelton 

13 

Peak. They flow to the east and leave the 

mountains in deep canyons cut in the Paleozoic 

and Mesozoic rocks that compose the front 

range. After leaving the mountains, the 

streams flow through an area of rolling hills 

carved in Cretaceous shales before entering areas underlain by Tertiary rocks. After en- tering the plains area, the three forks join 

and flow north and east to join the Powder 

River upstream from Arvada. Because most of 

the summer flow of the stream is used for irrigation, only a small part of it reaches the 

Powder River. 

Clear Creek 

Clear C~eek and its principal tributaries, 

Rock and Piney Creeks, rise near Cloud Peak 

and flow eastward through an area underlain 

by granitic rocks and leave the mountains by 

way of canyons cut in relatively narrow outcrops of Paleozoic rocks. Downstream from 

Buffalo, Rock Creek joins Clear Creek, which 

is in turn joined by Piney Creek at Ucross. 

From the mountains to its junction with the 

Powder River, downstream from Arvada, Clear 

Creek flows on a heavy bed of gravels between 

low banks. Wide flats on each side of the 

stream are used extensively for the cultivation of irrigated crops. The flow of Clear 

Creek during the irrigation season is con- trolled and augmented by storage in several 

lakes in the mountains and in Lake De Smet, a large off-stream reservoir 10 miles north of 

Buffalo. Lake De Smet had no surface outlet 

and was high in dissolved solids until inlet 

and outlet canals were built about 1921 between the lake and Piney Creek near Kearney. 

In 1949 the dissolved solids concentration of 

the lake water had been reduced to about 800 

ppm, and the lake is an excellent habitat for 

rainbow trout. The flow from the lake into 

Piney Creek is controlled by gates at the 

north end of the lake. 

Little Powder River 

The Little Powder River rises in the uplands near Gillette and flows almost due 

north to join the Po-wder River downstream 

from Broadus, Mont. Most of the area drained 

by it is underlain by the Fort Union formation of Tertiary age. Along the lower reaches 

of the river there are broad flats, but in some areas the land back from the stream is 

cut into badlands by gullies. The flow of the 

stream except during storms is usually not 

sufficient to carry large sediment loads. 

There are small diversions from the stream 

for irrigation, mostly of hay meadow~. 

Mizpah Creek 

Mizpah Creek rises in the uplands to the 

west of Broadus and flows northeastward to 

join the Powder River at Mizpah, Mont. The 

total drainage area of the creek is small in 

comparison with its length, and for the great- er part of the year it is a dry stream channel. During heavy storms it probably carries a large volume of sediment into the Powder 

River. Along the upper part of Mizpah Creek 

water is diverted by spreader dikes. The sediment carried by the water is deposited and 

is gradually building up the flood plain. 

This type of irrigation is also practiced on other minor tributaries of the Powder River. 
Figure 6.--Middle Fork Powder River above the junction of Red Fork. 

The river at this point still has some of the characteristics of a 

mountain stream, but evidence of the sediment transported during high 

flows is given by the raw stream banks. 

Figure 7.--Sediment-filled reservoir on Salt Creek near the town of 

Midwest. Dredge keeps a cooling water pool open for the power 

plant. Note the gullies and badlands in the background. 

14 

' . 
EROSIONAL AND DEPOSITIONAL PROCESSES IN AN 

AREA NEAR THE MOUTH OF SALT CREEK 

All the processes by which sediment may be 

moved from its place of origin to a temporary or final place of deposition are active in 

the Powder River basin. 

Erosional or depositional features are better understood if the relation of the feature 

under study to the rest of the system is 

known. In order to study erosional and depositional processes in detail, a small area near the mouth of Salt Creek was selected. In 

this restricted area erosion is active in the 

form of gullying, sheet or rill erosion, bank 

cutting, and soil creep. Moreover, depositional forms that go hand in hand with erosion are well-exhibited. 

Figure 8 is an aerial view of the terrain near the confluence of the Powder River and 

Salt Creek. The Powder River flows from right 

to left in the figure. A deep gully in the 

center of the area joins Salt Creek at co- ordinates 7.-4,6.3. The divide of one of the 

headwater tributaries o!' this gully· is a nar- row ridge at coordinates 1.4,14.0. The ridge 

itself is a product of erosion of nearly horizontal shaly siltstones. To understand the 

processes by which sediment moves, is temporarily deposited, and is again moved, one should trace the sediment from its origin on the divide until it reaches Salt Creek._ 

The accumulation of fine rock debris at the 

fo9t of the steep slope that leads down from 

the top of the divide is the result of a com- bination of factors. The slope is too steep 

for weathered bedrock material to remain in 

place; nevertheless, weathering is an important part of the process of removing material 

from the bedrock slope. The freezing, thawing, 

wetting, and drying of the surface loosen a thin layer of material that is carried to the 

foot of the slope by gravity or water or by both. 

Material has accumulated at the foot of the 

bare bedrock slope because of the change from a steeper to a gentler declivity. The gravitational force is sharply decreased, and the 

capacity of the water that flows from the 

steeper slope is insufficient to carry its 

load of sediment on the gentler gradient. 

Part of the sediment is deposited and an alluvial cone is built. Material will be added 

to the alluv~al cone until the slope is increased enough to insure a velocity of flow 

great enough to transport the debr+s supplied 

by the bedrock slope. 

Sheetwash aided by rain splash is the main cause of the downslope movement of sediment 

acrQss the alluvial cone. However, there is 

also a mass movement of the material in the 

alluvial cone. This mass movement is soil 

creep, which is a type of mass transport at a speed so slow as to be imperceptible to the 

eye. Soil creep is caused by. the force of 

gravity and is aided by water lubrication. 

The sediment moving over the surface of the 

alluvial cone enters the gullies that are eating into the foot of the cone. (See fig. 8, 

coordinates 1.8,13.6.) These gullies are advancing headward by caving and slumping of 

the headwalls as a result of undercutting and 

by the weakening of the coherence of material 

at the base of the headcut by the wetting 

15 

action of surface and ground water. The sediment enter•ing the gully from the alluvial cone and eroded from the gully itself is car- ried downstream mainly because of the incroased carrying capacity of the constricted 

flow. 

Part of the sediment eroded from the headmost gully is transported to Salt Creek without deposition, but part of it is temporarily 

deposited in the reach between coordinates 

2.9,12.8 and coordinates 7.2,12.3. (See fig •. 8.) Deposition in this reach is caused by the 

reduction of the sediment-carrying capacity 

of the flow by decrease in slope, retardation 

of the flow by vegetation and by spreading, 

and reduction of flow by infiltration. 

From the headcut at coordinates 6.2,12.3 

(fig. 8) to Salt Creek the gully is being 

widened by bank cutting and by the action of 

water that enters the gully over the tops of 

the banks. (See figs. 9 and 10.) Along most 

of this reach, a balance exists between degradation and deposition, but at the extreme 

upper end the channel is being deepened, 

whereas at the lower end it is being aggraded. 

Field inspection and information furnished by a local resident indicate that the headcut of 

this gully has advanced headward about 380 ft 

in the last 30 yr. If this advance began at 

the present mouth of the gully and has progressed at a constant rate, the gully must 

have begun to develop more than 500 yr ago. 

Relation of Local Base Level to Gully 

Formation 

The mechanics of gully cutting are fairly 

well established, but the causes that start a gully are not well known. Land misuse has 

been advanced as one of the causes of gullying. This includes any use of the land that 

has destroyed the protective vegetative cover. Another cause that has been suggested is a slow climatic change. Either of these can cause gullying and probably are the most com- mon causes, but a third cause of gullyinevhas 

not received the attention it merits. This cause is the change in temporary base level 

at the mouth of a tributary valley. 

Playfair 1 s law of accordant junction implies 

that the gradients of main streams are gentler 

than those of tributaries that join them. Be- cause main streams tend to attain grade early 

in the degradational part of the evolution of 

most geomorphic units, this is the relation 

generally observed. 

Even though the gradients of the tributaries are as steep as or steeper than those of 

the main stream, the smaller volume of flow 

will at times prevent the tributary streams 

from maintaining accordance. Where a wetweather, intermittent tributary joins a stream that has perennial flow, the differ- ence in volume of flow in the main stream and 

in the tributary is great. During and immediately after rains, a discordance or hangingvalley type of waterfall may be formed at the 

junction of the wet-weather and perennial 

streams. If the wet-weather stream has a fairly large draina.ge area, the waterfall may ad- vance an appreciable distance up the tributary valley. Between rains the perennial 

stream persistently deepens its valley while no erosion is occurring in the wet-weather 

stream. Discordant junctions resulting from 
2000 0 6000 Feet 

Figure B.--Aerial ph otograph or area near mouth or Salt Creek. Photo by 

Fairch i ld Aerial Surveys, Inc., ror Bureau or Reclama tion. 

16 
Figure 9,--Heatcut of gully that joins Salt Creek near its mouth. 

Figure 10.--Gully shown in figure 9 near confluence with Salt Creek. 

Compare the rounded profile of the top of the gully wall and the general eroded appearance of the walls with those in above photograph. 

~7 
18 

the above causes are common in arid and semiarid regions. 

The gully that joins Salt Creek at coordinates 7.4,6.3 (fig. 8) probably was started 

by undercutting of its stream channel by a meander of Salt Creek. The evidence in the 

field and from figure 11 indicates that previous to interception of its channel by the 

meander bend the stream emptied into the 

Powder River or possibly Salt Creek at about 

coordinates 7.0,3.4. (See fig. 8.) An extension of the top or bank profile of the gully 

(fig. 11) would intercept the surface of the 

dissected alluvial fan at about coordinates 

7.0,4.0. (See fig. 8.) The close parailelism 

of gradient between the present ~~lly bottom 

and the top of the gully bank (fig. 11) is 

additional evidence that the gully was started by an abrupt change in the temporary base 

level. 

RUNOFF 

Stream-Flow Records 

Although records of stream flow have been 

obtained by the U. S. Geological Survey at 29 

gaging stations (fig. 12) in the Powder River 

drainage basin, most records ~re for short 

periods. The records were obtained primarily 

to determine water supply for irrigation. 

Winter records often are incomplete. There are unmeasured diversions upstream from most 

gaging stations. As a result, the runoff of 

the Powder River drainage basin is incompletely defined by the stream-flow records that are now available. 

Figures of average discharge in cubic feet 

per second per square mile and the years for 

which tbe average was computed are listed in 

table 3 for each of 12 gaging stations. Drainage areas above the gaging stations are also 

given. The figures of average discharge ar-e unadjusted for irrigation diversions, but rec- ords for Clear Creek near Buffalo do include an estimated diversion for electric power of 

about 7 cfs. Because figures of average discharge are based on records for different periods, they are not directly comparable so fig- ures of average discharge during a 5-year period that ended September 30, 1950, are also 

listed. Table 3 shows that discharge per 

square mile varies widely within the Powder 

River drainage basin. 

Distribution of Runoff 

Figure 4 shows the approximate areal distribution of average annual runoff as based on stream-flow records· prior to September 30, 

1944 (Colby and Oltman, 1948, pl. 2). Average 

annual runoff from the entire Powder River 

drainage basin is a little less than 1 in. It 

is less than 0.5 in. over much of the basin. 

Along the crest of the Bighorn Mountains it 

is at least 15 in. and may be as high as 25 

in. for small drainage areas at high altitudes. The large differences in runoff are partly due to differences in the amount and 

rates of precipitation; but land slopes, temperature, vegetal cover, and soil types also 

affect the distribution of runoff over the 

basin. In a general sense, the distribution 

of runoff in the basin is governed primarily by topography. 

In the large areas of low runoff, most 

stream flow occurs during the late spring or during the summer and is caused by occasional 

rains of moderate to heavy intensity. Streams 

from these areas receive little ground-water 

discharge and are dry much of the time. Runoff from the areas of high' runoff follows a 

different pattern. Stream flow is high during 

May, June, and July when the streams are fed 

by melting snow. During the remainder of the 

year the runoff is fairly uniform, and base 

flow of the streams in the mountains is wellmaintained. 

Figure 13 shows variations in annual discharge in acre-feet per square mile for Clear 

Creek near Buffalo and for the Powder River 

at Arvada. The annual discharge for Clear 

Table 3.--Average discharge at gaging stations on the Powder River and its tributaries 

Number 

on map 

(i~~· 

3 

4 

6 

9 

12 

17 

18 

19 

21 

23 

26 

28 

Gaging station name 

Powder River at (near) Arvada, 

Wyo •••••.•••••••••• • •• ••••••• Powder River at Moorhead, Mont. 

Powder River near Locat~, Mont. 

Middle Fork Powder River near Kaycee, Wyo •••••••••••••••••• North Fork Powder River near Mayoworth, Wyo ••••••••••••••• Crazy Woman Creek near Arvada, 

Wyo ••••••••••••••••••••• · ••• •• Middle Fork Crazy Woman Creek near Greub, Wyo •••••••••••••• Clear Creek near Buffalo, Wyo •• Clear Creek near Arvada, Wyo ••• Rock Creek near Buffalo, Wyo ••• Piney Creek at Kearney, Wyo •••• Little Powder River at Biddle, 

Mont ••••••••.•••••••••••••••• 

a Approximate figure. 

Drainage area (square 

miles) 

6,050 

a 8,030 a 12,900 

980 

69 

956 

82.7 

120 

1,110 

60.0 

106 

a 1,540 

Years for which 

average 

is computed 

1917-50 

1939-50 

1935-50 

1939, 1941-50 

1943-50 

1940-43 

1945-50 

1918-27, 1939-50 1940-~0 

1946-50 

1942-50 

1939-42 

Average 

discharge 

(cfs per 

square 

mile) 

0.069 

.066 

.059 

.16 

.56 

.066 

.24 

b .64 

.20 

.62 

.95 

.016 

Mean discharge 

Oct • 1, 19 45, 

to Sept. 30, 

1950 ( cfs per 

square mile) 

0.047 

.069 

.057 

.16 

.52 

.29 

b .51 

.19 

.62 

.86 

b Includes about 7 cfs diverted into power company pipe-line about 1! miles upstream from 

gage.· 
500-------r----------~----------.-----------r---------~~--------~-----------r----------~----------,-----------, 

... 

LLI 

LLI 

I&. 

z 

~ z 

0 

... 

4 

> 

LLI 

..J 

LLI 

9000 8000 1·ooo 6000 5000 4000 3000 2000 1000 0 

DISTANCE, IN FEET 

Figure 11.--Profile or gully channel and bank from confluence with Salt Creek to headcut. 
••• 

EXPLANATION 

Gaging stations 

1 South Fo~k Powder River near Kaycee, Wyo. 2 Powder River at Sussex, Wyo. 3 Powder River at (near) Arvada, Wyo. 

4 Powder River at Moorhead, Mont. 

5 Powder River near Mizpah, Mont. 

5 Powder River near Locate, Mont. 

7 Middle Fork Powder River above Kaycee, Wyo. 8 Middle Fork Powder River at Kaycee, Wyo. 

9 Middle Fork Powder River near Kaycee, Wyo. 

10 Red Fork near Barnum, Wyo. 11 North Fork Powder River near Hazelton, Wyo. 12 North Fork Powder River near Mayoworth, Wyo. 

13 North Fork Powder River near Kaycee, Wyo. 14 North Fork Crazy Woman Creek near Buffalo, Wyo • 15 North Fork Crazy Woman Creek near Greub, Wyo. 16 Crazy Woman Creek near Buffalo, Wyo. 17 Crazy Woman Creek near Arvada, Wyo. 18 Middle Fork Crazy Woman Creek near Greub, Wyo. 19 Clear Creek near Buffalo, Wyo. 20 Clear Creek at Buffalo, Wyo. 21 Clear Creek near Arvada, Wyo. 22 North Fork Clear Creek near Buffalo, Wyo. 

23 Rock Creek near Buffalo, Wyo. 24 South Fork Rock Creek near Buffalo, Wyo. 26 South Piney Creek at Willow Park, Wyo. 2& Piney Creek at Kearney, Wyo. 

27 Piney Creek at Ucross, Wyo. 28 Little Powder River at Biddle, Mont. 

29 Little Powder River near Broadus, Mont • 

In operation on • Sept. 30, 1950 

[J 

Discontinued prior to Sept, 30, 1950 

0 SHERIOAN 

0 CASP£R 

10 .. 

W 'f 0 M I N ·G 

lncltx fiiGI) d Montano anct .,_.. sltOWifiQ the Powder RiVer droiftogt basin 

Figure 12•--Map showing locations of' gaging stations in the Powder River drainage basin. 

21) 
1000 ~---------r----------~--------~----------~---------.----------,----------, 

800 

\1.1 

..J 

~ 

\1.1 

a:: 

C( 

600 I I I v ~CLEAR I CREEK NEAR BUFFALO, WYO. ;::) 

0 

(/) (Includes diverson for power) 

a:: ro \1.1 .... Q. 

... 400 \1.1 

\1.1 

"-

I 

\1.1 

a:: 

u 

C( 

200 

I I I I I 

RIVER AT ARVADA, WYO. 

~9~1&;-------~=-------~~-------L--------~~-----=~--------_j ________ :J 

1920 192S 1930 193S 1940 194S 19SO 

Figure 13.--Annual discharge, in acre-feet per square mile, for Clea~ Creek near Buffalo and the Powder 

River at (near) Arvada, Wyo. · · 
22 

Creek near Buffalo includes the estimated 

flow that is dive~ted around the gaging station and through a power plant. During the 

period for which stream-flow records are available, the trend of discharge has been 

downward. 

The range in water discharge and the duration of different rates of flow are shown for 

the Powder River at Arvada (near Arvada prior 

to May 1919) by the duration curve on figure 14. . 

Diversions and Storage for Irrigation 

The flow of the Powder River and its tributaries is appreciably controlled by storage and diversions for irrigation. Some idea of 

the effect of irrigation can be obtained from 

the number of acres that are irrigated. According to field observations and to reports 

of the Bureau of the Census (1942, pp. 329, 

653, 654) 70,000 acres were irrigated by diversions from streams in the Powder River 

drainage basin during 1939, the last year for 

which information is published. About 10,000 acres were along Prairie Dog Creek in the 

Tongue River basin. Probably more than 35,000 acres were irrigated by diversions from Clear 

Creek and its tributaries. Nearly 10,000 acres were irrigated by diversions from the Middle 

Fork and its tributaries, and only a slightly smaller acreage was irrigated by diversions 

from streams in Crazy Woman Creek basin. 

In the Powder River drainage basin only Lake 

De Smet, usable capacity 25,000 acre-ft 

(Harbeck, 1948, p. 71), has a usable capacity 

larger than 5,000 acre-ft. Kearney Lakes and 

Cloud Peak Reservoirs and several smaller res- ervoirs have a total usable capacity of about 

10,000 acre-ft. 

FLUVIAL SEDIMENT 

Complete information on the sediment.yield 

of a drainage basin would include rates and 

quantities of discharge of the sediment that 

is transported both in suspension and as bed 

load, the particle-size distribution of the 

suspended sediment and of the bed load, the 

mineral composition of the sediment, and the 

principal sources of the sediment. This prog- ress report contains measured rates and quantities of suspended sediment and the results 

of particle-size analyses of suspended and 

deposited sediments. Computed rates of sediment discharge as bed load are also given for 

the Powder River at Arvada. 

Definition of Terms 

As the definitions of terms that relate to 

fluvial sediment are not completely standardized, some of the terms in this report are defined as follows: 

Sediment is fragmental material that originates from weathering of rocks and is transported by, suspended in, or deposited by water or air, or is accumulated in beds by other 

natural agencies. 

Fluvial sediment is sediment that is transported by, suspended in, or deposited by 

water. 

Suspended sediment or susrended load is sediment that moves in suspens on in water and 

is maintained in suspension by the upward com- ponents of turbulent currents or by colloidal 

suspension. 

Bed load or sediment discharfed as bed load 

includes both the sediment tha moves along in essentially continuous contact with the 

stream bed (contact load) and the material 

that bounces along the bed in short skips or leaps (saltation load). 

Sediment samtle is a quantity of water-sediment mixturehat is collected to represent 

the average concentration of suspended sediment, the average size distribution of sus~ 

pended or deposited sediments, or the specific 

weight of deposited sediment. , 

Depth-integrated sediment sample is a sediment sample that is accumulated continuously 

in a sampler that moves vertically at a cpnstant transit rate and that admits sedimentwater mixture at a velocity about equal to 

the stream velocity at every point. 

Sediment discharge is (a) rate at which dry 

weight of sediment passes a section of a stream or (b) quantity of sediment, as mea- sured by dry weight or by volume, that is discharged in a given time. 

Sediment rating curve is a curve of relation 

between water discharge and discharge of sediment. Usually the relation is between water 

discharge and suspended sediment, but it can be between water discharge and discharge of 

bed load or between water discharge and total 

sediment discharge (sum of sediment discharge 

in suspension and as bed load). 

Specific weight of sediment deposit is 

weight of solids per unit volume of deposit 

in place. 

The size classification used in this report 

is the classification recommended by the American Geophysical Union Subcommittee on sediment terminology (Lane and others, 1947, p. 937). According to this classification, claysize particles have diameters between 0.0002 

and 0.004 mm, silt-size particles have diameters between 0.004 and 0.062 mm, and sandsize particles have diameters between 0.052 

and 2.0 mm. 

According to Twenhofel and Tyler (1941, p. 

110): 

"The median, or median diameter, is the midpoint in the size distribution of a sediment 

of which one-half of the weight is composed 

of particles larger in diameter than the me- dian and one-half of smaller diameter. The me- dian diameter may be read directly from the 

cumulative curve by noting the diameter value 

at the point of intersection of the 50-percent 

line and the curve." 

Water discharge is the discharge of natural 

water of a stream. The natural water contains 

both dissolved solids and suspended sediment. 

Measurement of Suspended-Sediment Discharge 

Discharge of suspended sediment is proportional to the product of water discharge and 

average concentration of suspended sediment. 
100,000 

4 

) 

10,000 

0 

z 

0 

u 

laJ 

(/) 

0: 

laJ 1000 

\ 

\ 

' 

Q. 

'-r"'lo. 

-- ..... .... 

laJ """ '""-

laJ 

lL. ~ ~ 

-.o.-..... 

u - CD 

:::) 

(.,) tOO 

~ ............. ............. ~ - ....... 

z ~ 

...... 

~ 

.. laJ 

C!) 

0: 

<( 

~ 

\ , 

% 

u 10 (/) 

~ .. 

T 

0 

q 

0: I. 

laJ 

.... 

<( ' ~ 

: 

10 30 40 50 60 70 80 90 100 

PERCENT OF TIME WHEN FLOW EQUALLED OR EXCEEDED GIVEN AMOUNT 

Figure 14.-Duration curve of stream flow f'or the Powder River at Arvada, 

from Oct. 1,_ 191'7, to Sept. 30, 1950. 

23 
24 

Procedures for gaging the flow of streams are fairly well standardized and are explained in 

Water-Supply Paper 888 (Corbett and others, 

19 4:5). 

Concentration of suspended sediment in the 

Powder River basin was determined from depthintegrated sediment samples. These samples were collected either with the US DH-48 hand 

sampler or with the US D-43 sampler except when the temperature was below freezing at 

which times a modified Colorado River sampler 

,was used. 

At sediment-measuring stations, samples were usually collected by local observers at one vertical in the stream cross section, 

called the daily sampling station, once or twice a day except during periods of high or rapidly changing concentration or discharge 

when samples were taken more frequently. In 

addition, engineers periodically collected 

samples at the daily sampling station and·at 

three to five verticals in the cross section 

of each stream. These verticals were spaced 

to represent equal quantities of water discharge. Concentrations of samples from the 

different verticals were averaged to get the 

concentration for the cross section. At some measuring stations, the concentration of sam- ples that were collected at the daily sam- pling station varied consistently or erratically from the average concentration of the 

cross-section samples. At such stations, cor- rections were applied to adjust concentrations that were based on samples at the daily 

sampling station to concentrations for the cross section. 

The suspended-sediment samples were weighed in the laboratory. After the sediment had settled, the supernatant water was drawn off. 

The residue was filtered or evaporated, and 

the sediment was dried and weighed. Cor~ections were applied for. any appreciable quan- tity of dissolved solids that remained with 

the sediment after the water was evaporated. 

Daily mean concentrations of suspended sediment were computed by plotting the concentration of samples from the daily sampling sta~ 

tion on the gage-height graph, drawing a smooth curve through the plotted points, and 

picking the mean daily concentrations for the 

daily sampling station from this curve. If 

the concentration at the daily station usually differed appreciably from the average con- centration for the cross section, a coefficient, either variable or else constant 

throughout the year, was applied to adjust 

the concentration at the daily sampling station to conform with the concentration for 

the cross section of the stream. 

Discharge ~f suspended sediment in tons per 

day usually was computed by multiplying daily concentration in parts per million by mean daily water discharge in second-foot days and 

by 0.0027. The constant 0.0027 is correct on- ly when the weight of a cubic foot of watersediment mixture is about 62.5 lb. On days 

when both concentration and water discharge were changing rapidly, each day was subdivided, and sediment discharge was computed for 

parts. of the day. For days when no samples were collected, the daily discharges of sus- pended sediment were estimated on the basis 

of water diseharge, concentration for adjacent days, weather records, and records for 

other stations. 

Suspended-Sediment Records 

Since April 4, 1946, records of suspendedsediment discharge have been collepted tor 

the Powder River at Arvada, Wyo. Similar rec- ords have been obtained at the gaging station on the Middle Fork Powder River above Kaycee since April 22, 1949, and at six other gaging 

stations in the Powder River drainage basin 

since the spring or 1950. These records have 

been computed to September 30, 1950, and are summarized in table 4. Monthly and annual 

figures of suspended-sediment discharge are in tables 14 to 21. Locations of the stations are shown on figures 2 and 12. Records of 

suspended-sediment discharge at most stations were obtained only during the water year 1949-

50, when stream flow was tar below normal. 

Suspended-sediment discharge fluctuates 

with changes in any one of several interrelated variables, which include water discharge, turbulence and temperature of the 

flowing water, and the availability of sediments of each size range. Resulting fluctuations in discharge of suspended sediment are large and rapid and have only a general relation to water discharge. (See figs. 15 to 22.) 

Except, perhaps, at very high discharges or overbank flows, the sediment discharge gene~­

ally increases more rapidly than the water 

discharge because the concentration also 

tends to increase with water discharge. For 

this reason, discharge of suspended sediment 

is usually less than average during years of 

average water discharge, for an occasional 

year of high sediment discharge is likely to 

raise the average annual sediment discharge 

considerably above the median annual discharge. On streams, such as Salt Creek and 

the South Fork Powder River, on which most of 

the stream flow is caused directly by runoff 

from an occasional rain, the sediment ·discharge during one short period of storm run- off may exceed the average annual sediment 

discharge of the stream. 

Table 4 shows that concentrations and discharges of suspended sediment were low at gag7 ing stations on Clear Creek near Arvada, 

Crazy Woman Creek n~ar Arvada, and the Middle 

Fork Powder River above Kaycee during the per- iod of sediment records. Most of the water 

that passes these stations comes from the 

mountains. 

Suspended-sediment discharge measured at 

the gaging station on the Powder River at 

Arvada during a 5-year period ending Septem- ber 30, 1950, averaged about 5,500,000 tons 

per year. (See table 4.) This sediment discharge was transported by an annual water discharge or about 200,000 acre-ft, which is twothirds of the average annual discharge for 

the period of stream-flow records. The aver- age concentration by weight was 2 percent. As 

the drainage area upstream from Arvada is 

6,050 sq mi, 200,000 acre-ft of water represents an average depth of 0.62 in. over the 

drainage area. The annual runoff during the 

5-year period that ended September 30, 1950, 

would be about 0·.7 in. after adjustment for 

net irrigation diversions. 

Though little direct relationship exists between amount of runoff and quantity of sediment that is eroded, yet the maximum amount 

of erosion is effectively limited by the 

amount of runoff. In any area where the annual 

runoff averages less than 1 in., the average 
to 

en 

10,000 I I I I I I 11·11 I I I I I II II I I I I I II II I I I I IIIII I I I I 1·1111 I I I· I I 1111 

0 1000 

z 

0 

u 

1&.1 

en 

0:: 

1&.1 

a. 

... 

1&.1 

1&.1 

t&. i 1001 

en 

a 

0:: 

1&.1. 

... 

c • 10 

111111111 

tJJJ.II. ~-~~·.I r:: ~::::. I "I I I IIIII 

I I I I l< 

. . . . : . ~ .. I ., ,.111 ~I· . ~- I I ' . 

.. . . 

. .. ~ 

10 100 I 000 10,000 100,000 1,000,000 

SUSPENDED SEDIM£NT OISC1iARG£ IN TONS PER DAY 

Figure 15. --Re1a tion of suspended-sediment discharge to water discharge, SoUth Fork Powder River near Kaycee, Wyo., 

May 17, 1950, to Sept. 30, 1?50· 
0 

z 

0 

u 

ILl 

(I) 

a: 

ILl 

a.. 

.... 

ILl 

ILl 

ro &a. 

en u 

ii 

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! 

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a: 

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en 

a 

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10,000 

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I I 11111111 I 11111111 ·I 11111111 I 11111111. I 11111111 I 11111111 

!-• . 

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. 

.... 1-

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I' I I I I I I I II I I I I I I I I I I I I I I I I II I I I I I I I II I I I I· I I I II I I I I I I II I 

I 

tl 

10 100 I 000 1(\ 000 100,000 

SUSPENDED SEDIMENT DISCHARGE IN TONS PER DAY 

Figure 16. --Re1a tion of susvended-sediment discharge to water discharge, Powder River at Sussex, Wyo. , Mar. 1, 1950, to Sept. }0, 1950. 

1,000,000 
10,000 

0 1000 

z 

0 

u 

"' Cl) 

a: 

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~ 

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:::> 

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10 100 1000 10,000 100,000 

SUSPENDED SEDIMENT DISCHARGE IN TONS PER DAY 

Figure 17 .--Relation of suspended-sediment discharge to water discharge, Powder River at Arvada., Wyo., Apr. 4, 1946, to Sept. 30, 1950. 

. 

. 

1,000,000 
Q 

z 

0 

u 

1.1.1 

fn 

a:: 

1.1.1 

Q. 

t1.1.1 

1.1.1 

k. 

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a:: 

c 

% 

u 

fn 

Ci 

a:: 

1.1.1 

tc 

• 

10,000 

1000 

100 

10 

10 100 1000 10,000 100,000 

SUSPENDED SEDIMENT DISCHARGE IN TONS PER DAY 

Figure lB.--Relation of suspended-sediment discharge to water discharge, Powder River near Locate,Mont., 

Mar. 1, 1950, to Sept. 30, 1950. 

1,000,000 
10,000 

Q 1000 ) 

z 

0 

u 

w 

Cl) 

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w 

Q. 

... 

w 

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II. 

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c 

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; 

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--; 

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..., 

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I I I I 

fO 100 1000 10,000 100,000 

SUSPENDED .SEDIMENT DISCHARGE IN TONS PER DAY 

Figure 19.--Re1ation of suspended-sediment discharge to water discharge, Middle Fork"Powder River aboVE# Kaycee, Wyo., Apr. 22, 1949, to Sept. 30, 1950. 

1,000,000 
0 

z 

0 

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. •- e I e 

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........ =---·- ' 

I 

. 

IL-----~--~~~~~~~~------._--~~~~~~~~----~--~--~_.~~~~------~--~~--~~~~------_.--~--~~_.~~~------~--~~~~~~~ 

I 10 100 1000 10,000 100,000 

SUSPENDED SEDIMENT DISCHARGE IN TONS PER DAY 

Figure 20. --Relation of suspended-sediment discharge to water discharge, Middle Fork Powder River near Kaycee, Wyo. , Mar. 1, 1950·, to Sept. 30, 1950. 

1,000,000 
10,000 

0 1000 z 

0 

u 

1&.1 

(/) 

ct: 

1&.1 

a. 

... 

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L I I IIJIIII I I II IIIII -~I --~1 ____;; J I I II II I I I IIIII I I 10 100 I 000 10,000 100,000 

SUSPENDED SEDIMENT DISCHARGE IN TONS PER DAY 

Figure 21..:..-Re1s.tion of suspended-sediment dischar~ to water dischar~_, Crazy Woman Creek near Arvada, Wyo._, Mar. 15, 1950, to Sept. 30, 1950. 

1,000,000 
0 

z 

0 

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I 

I 10 100 I 000 10,000 100,000 

SUSPENDED SEDIMENT DISCHARGE IN TONS PER DAY 

Figure 22.--Relation of suspended-sediment discharge to water discharge, Clear Creek near Arvada, Wyo., 

Mar. 21, 1950, to Sept. 30, 1950. 

1,000,000 
33 

Table 4.--Summary of records of suspended-sediment discharge for the Powder River drainage basin 

Number Dr.ainage Water Suspended- Average 

dis- concen- on map Gaging station area Period of record charge sediment tra- (fig. (squar~ discharge 

12) miles) (acre- (tons) tion* 

feet) {ppm) 

1 South Fork Powder River near Kaycee, Wyo •.••••• 1,150 May 17 to Sept. 30, 1950 4,110 76,640 13,700 

2 Powder River at Sussex, 

Wyo .••••••••••••••••••• 3,090 Mar. 1 to Sept. 30, 1950 99,780 1,500,000 11,000 

3 Powder River at Arvada, 

Wyo •••••••••••••••••••• 6,050 Apr. 4 to Sept. 30, 1946 120,600 3,774,000 23,000 

Water year 1946-47 274,800 5,323,000 14,200 

Water ye~r 1947-48 248,900 9,428,000 27,800 

Water year 1948-49 184,000 4,883,000 19,500 

Water year 1949-50 131,700 2, 738,000 15,300 

6 Powder River near Locate, 

Mont •••.••••••••••••••• a 12,900 Mar. 1 to Sept. 30, 1950 255,900 4,310,000 12,40Q. 

7 Middle Fork Powder River 

above Kaycee, Wyo •••••• 450 Apr. 22 to Sept. 30, 1949 27,780 70,600 1,870 

Water year 1949-50 49,680 108,800 1,610 

9 

17 

21 

Middle Fork Powder River near Kaycee, Wyo ••••••• Crazy Woman Creek near Arvada, Wyo •••••••••••• Clear Creek near Arvada, 

Wyo ••••••••.••••••••••• 

* WeiShted with water discharge. a Approximate figure. 

980 Mar. 

956 Mar. 

1,110 Mar. 

annual depth of soil that can be eroded from a drainage basin cannot exceed a fraction of an inch. If a cubic foot of the soil of a drainage area weighs 80 lb and the maximum 

concentration of sediment cannot reasonably 

be expected to exceed 250,000 ppm by weight, 

the maximum depth of erosion that accompanies 

1 in. of runoff can be computed as follows: 

1. An inch depth of water on a square foot 

of area is 62.4 lb divided by 12 or 5.2 lb. 

(The assumption is made here that 1 in. of 

runoff is clear water only, because much sediment may be deposited from the water before 

the water is measured.) 

2. At 250,000 ppm, three-quarters of the 

sediment-water mixture is water and one-quar-

-ter is sediment. Hence, 5.2 lb divided by 3 or 1.73 lb of sediment will be in the mixture. 

(If the specific gravity of the sediment is 

2.65, the water-sediment mixture would cover a square foot "or area to a depth of l.l2f? .in.) 

3~ 1.73 lb divided by 80 is 0.0216 or the 

fraction of a foot of soil that could be eroded from a square foot of area by 5.2 lb of wa- ter. This is equivalent to 0.26 in. 

The concentration of 250,000 ppm would be 

attained only whe~ the soil was very easily 

erodible and the-intensity of runoff was ex- ceptionally high. A much more usual concentration would be 50,000 ppm, which would indicate a depth of erosion of 0.04 in. per inch of 

runoff, 

Of course the average depth of net erosion over a large drainage basin can be computed 

from the measured sediment yield of a drainage 

basin, but it will normally be somewhat less 

than the average depth of erosion 'that may be 

expected for many small drainage areas within 

the large drainage basin. On large drainage areas the average depth will be reduced by inclusion of areas where only small amounts of 

erosion occurred and may be further reduced by 

1 to Sept. 30, 1950 66,600 363,400 4,010 

15 

21 

to Sept. 30, 1950 27,000 107,300 2,920 

to Sept. 30, 1950 81,630 52,670 470 

deposition in some parts of the basin or may 

be increased by channel scour. 

Nothing in this discussion should be interpreted to mean that erosion removes even an approximately uniform depth of soil from either large or small areas. It is intended on- ly to establish a rough limit of possible depths of erosion that may be expected to ac- company an inch of runoff. Also, the depths 

of erosion that are discussed here are for 

drainage areas without inflow of water from 

outside the areas. 

Size Composition of Suspended Sediment 

At all gaging stations where records of sus- pended-sediment discharge were obtained, representative samples were collected periodically for particle-si2e analyses. One or both of 

two general types of particle-size distributions were determined from a sample. One type 

showed particle sizes according to settling 

velocities in native water in wpich the degree 

of flocculation may have been about the same as in an assumed pool or reservoir. The other 

type of particle-size distribution was the 

classification of particles by their settling 

diameters when the· particles were completely 

dispersed. For particle sizes smaller than 

0.031 mm, the difference between the two types 

of particle-size distributions is large. The 

difference is due to flocculation of the soil 

particles, which is cau~ed by the calcium and 

magnesium cations from dissolved solids in 

the native water. Average size distributions 

of samples for which duplicate portions were analyzed in native water and in distilled wa- ter are plotted on figure 23 for the Powder 

River near Arvada. Also plotted is the curve of average particle size for all samples ana- lyzed in distilled water. Average particle 

sizes were not weighted with sediment discharge; they are simply arithmetic averages 

of the size distributions of the samples. Median particle sizes were taken from figure 23 
Ul 

tJ!o. 

,99.9 

99.8 

I 

99.5 

99.0 

98 

95 

90 

Q: 

w eo z 

LL. 

70 

.... 

z 60 

LIJ 

0 

Q: 50 

w 

Cl. 40 

30 

20 

10 

5 

t-------+-----;----+----i-+--+---+--+- ---------r---·-· ,____ - - r--"- -- ·-·--- ---- -- -- -·- -- ... ··--·- ---·- -·- --- - 1---+-

?: 

_, ,' I ~~~ I -~~~~~~~~ 

I _/~_,#""I /~~ 

_#"' ! 

..oiii!'E.oi~· ~~~~~ ... 

........ ~,..... 

~~-· ---~ 

~~ 

~~/ 

~~ ........... - / ..,JIA~~ /p 

-~~ / ~~ ~-

IV EXPLANATION ~-----~----~---r--+-~~~~~--~--~-----r--~-- -~ 

, ---- '/ .Average particle sizes of duplicate samples I analyzed rn dispersion medium ~------~----~~-r--+-~~~~~-----~----~---r-- -~ 

,)/ Average pa·rticle si;;$-;," du.pl icate _samples 

. ~ onatyzed in native water -~ 

.....-

2 

~ · 1 Average por.ticle sizes of. all samples++ 

~----~----+----+---+-~-+--t--t--it------+---+---+--+--t--~l- 0~ o lyz ed in cti ~per s i o ~ m~ diu~ T II 

0.001 

. 2 3 4 5 s 1 8 9 2 ~- 4 s ~- 1 , , ·I· 2 3 4 s 6 1 8 , 

0.01 0.1 1.0 

DIAMETER IN · MILLIMETE-RS 

Figure 25.--Average particle-size distributions or suspended-sediment samples, Powder River at Arvad~, Wyo. 
and from similar figures for other stations 

where sediment records have been collected. 

They are listed in table 5. 

Particle sizes as analyzed in native water are helpful in estimating the rates and locations of sediment deposition in slowly moving 

parts of a stream and in reservoirs. However, 

the degree of flocculation in a res,ervoir may 

not be the same as in the sedimentation cylinder in the laboratory. 

Absolute particle sizes, measured by settling velocities of dispersed particles in 

distilled water, are probably the most suitable size distributions for computing the specific weight of sediment after it is deposited 

in a reservoir. Sediment particles, even though they may flocculate to a larger settling diameter in the process of deposition, 

may, after they are deposited in a reservoir, 

still retain the physical properties of the 

individual particles. Floccules can be dispersed by mechanical agitation. Therefore, the 

bonds that hold together the individual sediment particles are not strong enough to give a floccule the physical properties of an individual sediment particle. For this reason the determination of specific weights that are based on particles sizes should be computed 

from particle sizes obtained by analysis of 

dispersed particles. 

Until 1950 the particle-size analyses both 

in native and in distilled water were made with 

the bottom-withdrawal tube. During 1950 many 

samples were analyzed for particle size by the 

sieve-pipette method. In this method particles coarser than 0.0625 mm are separated from the 

finer particles by a combination of wet and 

dry sieving. The coarser portion is then 

weighed and discarded or is subdivided into 

different size classifications by dry sieving. 

The finer portion is analyzed according to 

sedimentation diameters by the pipette method. 

The suspended sediment transported by the 

Powder River is mostly fine material. (See 

fig. 24.) The average percentage of particles 

smaller than the lower limit of sand size 

(0.062 mm) was between 81 and 89 percent for 

all stations except the South Fork Powder 

River near Kaycee for which 97 percent of the 

suspended sediment was finer than sand. The partic~e-aize curves of figure 24 were baaed ·on average sizes that were not weighted with 

either water or sediment discharge except that 

samples for size analysis were collected much more frequently at high discharges than at low 

discharges. Median p~rticle sizes (table 5) 

based on the average size distributions for 

35 

the different sampling stations were all 

smaller than 0.009 mm for samples that were analyzed in a dispersion medium. Median particle sizes of duplicate samples are for comparison between themselves only. For some stations they are based on only one of two·samples, and these samples were collected when 

the concentration was high. The size distributions of individual analyses are listed in 

tables 22 to 29 • 

Specific Weight of Fluvial Sediment 

Estimates of rates of reservoir depletion 

by sediment deposition require a knowledge of 

the probable location and specific weight of 

the deposited sediments. The location of the 

deposited sediments is dependent upon inflqwoutflow relationships or elevation of water 

surface in the reservoir, sedimentation diameter of particles in transport, mineral con- stituents in solution, and effect of density 

currents. The specific weight of sediment deposits depends upon the type of material in 

transport, primary p~rticle size, effect of 

change in concentration of the mineral con- stituents in solution, degree of sorting, and 

amount of consolidation. 

The rate of deposition of sediment in the 

upper reaches of a reservoir is a function of 

the stream velocity (turbulence) and settling 

diameter of the material in transport. The co~rse material will be deposited where the 

backwater begins, and much of the finest ma- terial will eventually reach the downstream 

end of the reservoir because of density cur- rents or reservoir drawdown or both. The res- ervoir operation may thus result in deposition of coarse and fine material in alternate 

lenses at the same location. 

The specific weight of sediment deposita in 

reservoirs increases with compaction. If all 

sediment particles have about the same specific gravity, the specific weight of sediment 

deposita depends upon the porosity of the deposit. Theoretically, if the sediment particles are uniform spheres and touch one another, the porosity depends upon the arrangement 

of the particles and not on the particle size. 

However, the porosity changes greatly when 

particles of different sizes are intermixed, as the smaller particles partly fill the pores 

between the large particles. Deposits of silts 

and clays have greater porosity and smaller 

specific weight than deposits of larger particles partly because the range in size may 

be greater in the coarser deposits. 

Table 5.--Median particle sizes from unweighted average size distributions of suspended sediment 

for stations in the Powder River drainage basin 

Duplicate samples All samples 

Sediment station Analyzed in Analyzed in analyzed in a native water distilled water dispersion medium 

(millimeter) (millimeter) (millimeter) 

South Fork Powder River near Kaycee, Wyo •••••• 0.010 a 0.0018 a 0.001 

Powder River at Sussex, Wyo ••••••••••••••••••• .011 .0035 .0040 

Powder River at Arvada, Wyo ••••••••••••••••••• .016 .0057 .0058 

Powder River nea~ Locate, Mont •••••••••••••••• .012 .0034 .0030 

Middle Fork Powder River above Kaycee, Wyo •••• .015 .0089 .0084 

Middle Fork Powder River near Kaycee, Wyo ••••• • 021 .0245 . .0080 

Crazy Woman Creek near Arvada, Wyo •••••••••••• .015 .0140 a .003 

Clear Creek near Arvada, Wyo •••••••••••••••••• ~ ............. . ............... .0062 

a ~stimated by extrapolation. 
i 

Cl'1 

()) 

99.9 

99.8 

99.5 

99.0 

98 

95 

90 

a: 

weo z 

ii: 

70 

.... 

z 60 

l&J 

0 

a: 50 

liJ 

0.. 40 

30 

20 

10 

5 

2 

I 

0.001 

, ~ ...... !-' ....... 

... ~ 

~ ... ~~ ...... 

·''·' ~....--:.·. .,./ ~-·./ v .·· / 

~ ~ 

/~ ~y v ~, ~ ~ .. ·· 

·~'' v ~: 

~/ v :~ ~ r;j 

V'~ ~oo•~ ~ .... """': 

~ ""' ~ • ~ ~ .......:' B.; ~ ~ ~ 

~ .. .......-: _, ~ .... liT 

v ~ ~ ~~ ,....... 

~~ ~":: ;,....., 

~ ~ jill' ~ .., -..=-k':.~ r~ ~ .. to--=~ 

~ ~ ~ ~-- -~ ~ ~-

~ 1.~ ~ ~ 

v ..JP~ ~ ~"'"'" 

V"' EXPLANATION 1-

1-

--- South Fork Powder River near Kaycee, Wyo. 

----- Powder River at Sussex, Wyo. 1-

-- Powder River at Arvada, Wyo. 

Powder River near Locate, Mont. 

·-·- Middle Fork Powder River above Kaycee, Wyo. 1-

--- Middle Fork Powder River near Kaycee, Wyo. 

-··- Crazy Woman Creek near Arvada, Wyo. 1-

. . . .. . . . . .. Clear Creek near Arvada, Wyo . _l _L I I I I I I I 

J ~ I I ~ I I ·1 I 2 3 4 5 6 ., 8 9 4 5 7 8 9 2 ~ ! ~ 1 ~ ! • 

0.01 0.1 1.0 

DIAMETER IN MILLIMETERS 

Figure 24.--Average particle-size distributions of all suspended-sediment samples analyzed in dispersion medium. 
An increase in specific weight and a reduction in volume of deposits are usually accom- plished by squeezing out part of the interstitial water and by closer packing of the sediment particles. The smaller the pore spaces 

are, the lower is the permeability and the 

slower is the release of the interstitial wa- ter. Hence, fine-grained deposits usually com- pact at a much slower rate than coarse-grained 

deposits. The rate and the amount of increase 

of specific weight depend not only on the particle size of the deposits but also on the 

method of operation of the reservoir. Consolidation is probably rather rapid .in the first 

few years after deposition but decreases with 

time. 

The determination of an average figure for 

the specific weight of a deposit that might 

be formed from the sediment in transport is 

necessary to ascertain the space the sediment 

will occupy in a reservoir. The accuracy of 

the determination is affected not only by res- ervoir operation but also by the inaccuracies 

introduced in measuring the total sediment 

discharge. At present only the suspended sediment is measured; the bed load must be estimated. Only an approximate figure for the av- erage specific weight, which the material 

will assume on deposition, can be computed. 

Median Particle-Size Method 

The specific weight of a deposit that might 

be formed from a suspended sediment was com- puted by a method based on the median particle size of the suspended sediment. This method is believed to be superior to others that 

apply specific weights to different size 

grades because it is simple and is based on actual measurements of specific weights. 

This method was applied as follows: The 

median particle size of each sample that was analyzed in a dispersed state was plotted 

against the instantaneous suspended-sediment 

discharge in tons per day. (See fig. 25.) The curve of figure 25 was so drawn that on the 

basis of the available particle-size analyses an average of about 50 percent by weight of 

the particles within each of several ranges 

of sediment discharge would be finer than the 

median size indicated by the curve. For predetermined class intervals of suspended-sediment discharge, the corresponding median particle sizes were taken from the curve of fig- ure 25 and were listed in table 6. 

Figure 26 shows the relation between the me- dian particle size and the specific weight of 

relatively uncompacted sediment deposits in 

37 

reservoirs in the Powder River drainage basin 

and other drainage basins. The data from 

which the figure was prepared are in table 30. 

These data are for samples that were all or nearly all collected near the surface of submerged sediment deposits. Thus the specific 

weights of the samples are representative of 

natural deposits that have been formed, probably within a few years of the sampling time, 

and that have not been compacted materially 

by overlying deposits. 

The specii'ic weight of a deposit that might 

be formed from the suspended sediment of the 

Powder River at Arvada was then computed as shown in table 6 and was found to be 56 lb 

per cu ft. This specific weight, which is for a sediment deposit that has not been compacted du~ing a long period of time or under the 

weight of appreciable amounts of overlying deposits, was used to convert tons of suspended 

sediment to acre-feet of sediment. (See table 

7.) The computed volume, 21,420 acre-ft, .indicates the probable maximum space that would 

be occupied by the suspended sediment that was discharged by the Powder River at Arvada 

from April 4, 1946, to September 30, 1950, 

after deposition in a reservoir. 

Size-Distribution Method 

A second method of computing the specific 

weight of a deposit that might be formed from 

suspended sediments is the size-distribution 

method. This method consists of dividing the 

sediment into ·-size fractions and computing 

the specific weight of the deposit from the 

percentages of each size fraction and from 

the density of each size fraction. 

To determine the average distribution of 

sand, silt, and clay in the suspended sediment of the Powder River at Arvada, the percentages of these size fractions were taken 

from the particle-size analyses that were made in distilled water. The percentages of 

each size fraction were plotted against the 

suspended-sediment discharge in tons per day. 

Average curves were drawn through the plotted 

points. If these three curves are assumed to 

represent adequately the variations in the 

size distributions of suspended sediment with 

sediment discharge, the average percentage 

distribution of clay, silt, and sand can be 

determined as follows: 

1. Select class intervals of suspendedsediment discharge in logarithmic progression. 

2. Tabulate for each class interval the percentage of sand, silt, and clay as shown by 

Table G.--Specific weight based on median particle size for the Powder River at Arvada, Wyo., 

Oct. 1, 1946, to Sept. 30, 1950 

Suspended-sediment discharge Median 

Class- interval Middle of particle size 

(tons per day) class interval Total tons (millimeter) (tons per day) 

0- 3,500 1,750 597,000 0.0059 

3,500- 14,000 8,750 1,810,000 .0078 

14,000- 58,000 36,000 5,420,000 .0090 

58,000- 150,000 104,000 5,630,000 .0098 

150,000-1,600,000 875,000 9 '420 ,000 .0100 

Total •••••••• ................ ~ 22,877,000 . .. . . .. . . . . .. . . 

Specific weight in pounds per cubic foot = 22,877,000 = 

404,994 56.49. 

Specific Total tons. 

weight divided by 

(pounds per specific 

cubic foot) weight 

53 11,264 

55 32,909 

56 96,786 

57 98,772 

57 165,263 

.............. 404,994 
~ 0 

a:: 

w 

0.. 

(/) 

z 

f2 

z 

w 

(!) 

a:: 

4 

;J: 

(.) 

(/) 

a 

.... 

z 

w 

:& 

0 

w 

(/) 

0 

w 

0 

z 

w 

a.. 

(/) 

::::> 

(/) 

I,OOOPOO 

100,000 

10,000 

1000 

100 

10 

0.0001 

I 

I 

I 

I 

I 

• 

4 

4 

I 

,, 

I 

~ I • 1 

• 

I 

I 

~ I 

• I I 

I I 

I 

I 

I 

I 

J 

I 

I 

I' 

0.001 0.01 

DIAMETER IN MILLIMETERS 

• 

• 

.. 

I• 

• 

•• • 

• .. t• 

• 

• • 

.. 

• ... 

" 

0.1 

Figure 25.--Median particle size versus suspended-sediment discharge, Powder 

River at Arvada, Wyo. 
1.0 ·~==-=-~:.:-:..~----_-__ ...,..l-----------------~ __ -__ -_-__ -. ..., __ r-r--------_-_ .... _-_-_-__ -__ ....-_-_-_-__ -...----_-_....-_-_-_-_-__ ...,.._-_::_:-.. ~------------_...,.._6-.. -_.-.-Ll-....-v--. 

-- -~ ,-=~=- ---- -~_:-:· ---- ..... ----,--- ----- ---- -=~~V-t -

CJ) 

0: 

~ 0.1 ~ 

~ 

~ 

...J 

...J 

~ 

z 

---~------- EXPLA:ATlON f-- --- ----u·:-·-----·- ------ -Samples collected from reservoirs in the -- ·a-- -----v_---- --- ·· · --- = P::::~~sR~:~~e;::~nai:e ~::;: -+-----+-~-~~--1~-- _J~ _ _ _ _ -~-~--- drainage basins i 

I 

I 0 

0 

____ !_. ____ __,_ -----r----- ------~ --- -+-r----+----1 ..---+----~----------

,___. · --- --- --+----=~~~;·_-_-_---_------+-~~ ! __ -~- ~-=-----~~--r~---~-~----~1 , I 

·~ 

~ 

1-----1--~- ----- 1-- ---·-- ----- -- -- __:_ i-·- .. --- - -------- -·-----+------ --- --+-----+-----f 

1----·-i--·--------·-- ----~--- . ---·---~+----Q --- - ~---I------·:---- ------f----tf------4 

1----+----+-------+---'----+-------------+--------~ • 0; ----+·-'-·-·-r-----+-·---t----

•1 

-·------+----~-----+----~r-----r--- ~----~-~-+--·---1-------t----t------1 i I ~ o r · --~~~-~-------r-·~·----~----+-------- 00 c 0 

~ 0 

~ 0 0 c u 

~ I ~ 

~ 0 0 Oe •1 

i Ml t------1--->--c;---~ ;__ __ 00 ~~l~- ~-- ~ 00 - - -- ------t----+----t 

~ r---+ ~~ =-~=-:- -~ --_- -~--- c-~~-~J .-----! ~- :_~- -~~ ~::_ r==-~~~1_::~~ --,____ __ r---

~L ___ --~-+~~-0 ~~i!; -1~- ~-E~-=- --F ~~---,-~ ----~-- c--------- _,_ - ----.-~-.~~ -<> --+=-- ------ --~ r-- --~---------..=-~ ~---:.!!.- 0 l -_ --'--t---+----t----1 

• • 000 ,~~0·... . I ~ I 

-----+-----+-------•--0-c·;- -~--·--~----or--r~--- . -- 0 0 

0 0 

noo•------~~------------._----~~--_.----~------~----._ ____ ._ __________ _. __________ ~ 

0 10 20 30 40 50 60 '70 80 90 

POUNDS PER CUBIC FOOT 

100 110 

Figure 26.-Relation oi' specif'ic weight of sediments depos'i ted in reservoirs 

to median particle size. 

39 

120 130 
40 

Table 7.--Volume of suspended-sediment discharge at 56 lb per cu ft, Powder River at Arvada, Wyo. 

Period 

Apr. 4 to Sept. 30, 1946 .................•... · .. 

Water year 1946-47 ............................. Water year 1947-48 ••••••••••••• 0 0 •••••••••••••• 

Water year 1948-49 ••••••••••••••••••••••••••••• Water year 1949-50 ••••••••••••••••••.•••••••••• 

Total •••••••••••••••••••.•••••••••••••••• 

the average curves of percentage of each size 

fraction versus suspended-sediment discharge. 

. 3. Compile a frequency table of suspendedsediment discharge from the daily sediment 

discharges during the four complete water 

years of sediment records of the Powder River 

at Arvada to determine the different tonnages of suspended-sediment discharge in each class 

interval of suspended-sediment discharge. 

4. Compute the average percentage distribution of sand, silt, and clay from the tonnages 

and percentages in each class interval. 

By this method of weighting with sediment 

discharge, the average percentages of sand, 

silt, and clay in the suspended-sediment discharge of the Powder River at Arvada during 

the period of 4 water years that ended September 30, 1950, are 20, 43, and 37 percent by weight, respectively. Clay was assumed to include all particles finer than 0.005 mm; silt, 

those between 0.005 and 0.05 mm; and sand, 

those between 0.05 and 1.0 mm. These are the 

size ranges for which Lane and Koelzer (1943, 

p. 49) state densities of 93, 65, and 30 lb 

per cu ft for the sand, silt, and clay fractions 1 yr after deposition in a reservoir in 

which the sediment deposit is always or near- ly always submerged. ~pressed in cubic ·feet, 

the volume occupied by 1 lb of the deposit 

that might be formed from the suspended sediment of the Powder River at Arvada would be 

0.20 + 0.43 

93 65 

+ 0.37 

30 0.0211 

and the specific weight at the end of 1 yr would be ___ 1___ or 47 lb per cu ft. 

0.0211 

The size-distribution method of computing 

the initial specific weight of the sediment 

deposit that might be formed from the suspended sediment of the Powder River was also applied to the size ranges and the initial densities as determined by Parker Trask and re- ported by Lane and Koelzer (1943, pp. 30-31). 

In these size ranges, clay includes all particles finer than 0.004 mm; silt, those between 0.004 and 0.062 mm; and sand, those between 0.062 and 0.5 mm. The sand, silt, and 

clay percentages computed by weighting with 

sediment discharge are 19, 46, and 35 percent 

by weight, respectively. In cubic feet the 

volume occupied by 1 lb of sediment deposit 

with these percentages of the three size fractiens and with the initial densities as re- ported by Trask would be 

0.19 + 2.:..12 + ~ 0 ooz6 88 67 13 = . v 

and the init"ial specific weight would be 

1 or 28 lb per cu ft. This low figure for 

'0:0'3'6 

Suspended-sediment Volume of 

discharge 

(tons) 

deposited sediment 

(acre-feet) 

3,774,000 3,090 

5,323,000 4,360 

9,428,000 7,730 

4,883,000 4,000 

2,738,000 2,240 

26,146,000 21,420 

initial specific weight is for sediment deposits that were formed during "a very short settlement period." 

Sediment Transported as Bed Load 

Because sediment transported as bed load in 

the Powder River has not been measured, empirical formulas developed from extensive laboratory experiments and limited field data were used to compute the approximate discl'.arge of 

sediment in the form of bed load. Selection 

of independent theoretical approaches to bedload determinations was somewhat simplified 

by the fact that nearly all are based on the 

concept of shifting layers of bed material 

that are kept in motion by the shear of the 

moving fluid. Bed-load formulas by Einstein 

(1950),Du Boys (1879, PP• 149-195), and 

Schoklitsch {Shulits, 1935, PP• 644-687) were used. 

A representative cross section of the Powder 

River at Arvada, Wyo., was determined by aver- aging three cross sections (fig. 27) near the 

recording gage. Water levels for five repre- sentative water discharges that ranged from 

20 to 12,000 cfs were taken from a stage-discharge rating table. Mean depths and widths 

for the selected discharges were obtained 

from the average cross section. (See fig. 28.) 

The slope of the water surface was determined between the recording gage at Arvada and 

the highway bridge· 2,100 ft downstream from 

the gage. Thirteen observations of the slope 

ranged from 4.70 to 5.86 without apparent cor- relation with water discharge. An average 

slope of 5.28 ft per mile, or 0.001 was used 

in the computations. 

A median particle diameter of 0.228 mm or 0.00898 in. was taken from the average particle-size distribution curve of the bed material (fig. 29) and was used in Du Boys' and 

Schoklitsch's formulas. 

Du Boys' Formula 

Boyer and Laursen (1950, pp. 815-817) pro- po~ed the following form of the Du Boys' formula for computation of sediment discharge as bed load: 

in which qs =rate of bed-load-transport in 

pounds per second per foot of 

width 

K = a constant 

d = median particle diameter of the 

bed material in millimeters 

y

8 = mean depth in feet = hydraulic slope 
tl:>o 

1-' 

1-

l&J 

l&J 

LL 

z 

10 12,000 c fs 

gr--T---r--+-~--~--1---r--+---r--+--4--~--+---~-+--~--+--4--~--+---~-+~~--~~~~--4-~ 

ar--T---r--+-~--~--1---r--+--~--+--1--~--+---~-+--~--+--4--~--~~~~L-4---~~--~--4-~ Cross section 3 

from \ 

7l-\ 

\ 

6H ~ 5 ~ ~ -- - ~ -- --·1 ~- -~~ ----t----- / /_--..r7 

&1.1 :z: 4 _l_ \ I /400 _I_ c I ts I ;' 1.' /1 "---...._Cross ' ~ect1on . 2 is at 

\ 

T ..t 1 recordtng gage 

...l. 

73000cfs 

&IJ l, \ 1- I --- l:?1 1 1' i 1 

(!) 

3 

·• -.-- --~o- .100 cfs ..... ' ! J i -- .,/ , <[ ' - \ .L':L. ' , I ..,_,_ \ ...L.,. 

(!) ...._, v ,1- ~~- ·..._~j.- _-...... r--- 1.. ..,..,., ...-~ I IX 

2 

' v' \ ,-r- ~ -. --7 -......c ---7'1 

~ Z ~ ' ' ' -.~-. V I 

-' \~' \ I - -., ', r •-' ~~0 cIs \ / ~ ~I' 

0 o 20 40 60 eo 100 120 140 160 1eo 200 220 240 260 2eo 

DISTANCE FROM PEG ON LEFT BANK, IN FEET 

Figure 27.--~ee cross sections or the Powder River at Arvada, Wyo. 
1-

liJ 

liJ 

lL 

z 

..... 

:I: 

C) 

liJ 

:I: 

liJ 

C) 

~ <t ro C) 

12 

10 ~ 

9 

8 

7 

6 

5 

4 

3 

t-

\ 

\ 

' 

2 

0 

0 

- '-·- - - -

- - - - - -

- - - - - ~ 

~- - - - - - ~ - ~ ~ ~ [\ / 

\..-

20 40 60 

Gage height in feet 

2.73 

3.18 

3.79 

5.61 

9.83 

. .,.-12,boo Ls - - - ---- - - '- - - - - - - - - - -

- lL:: 

I 

v I" 

·3000 cfs 

- r- --- --- - - - - - / 

- rV-400 cfs ~ - ____._-

l/..100 cfs - 1-- - - V' - - - L.20 

~-:---

c fs - - --r ~ 

~ ............... '-.I 

v- ~ v ~ 

~--~ -

80 100 120 140 160 180 200 220 240 260 

DISTANCE FROM PEG ON LEFT BANK, IN FEET 

SECTION CHARACTERISTICS 

Discharge in cubic feet per second 

20 

100 

400 

3,000 

12,000 

Area in square feet 

28.8 

72.4 

179.2 

515.6 

1,447.2 

Width in feet 

90 

149 

168 

194 

281 

Mean depth in feet 

0.320 

.485 

1.066 

2.657 

5.150 

Figure 28.--Average of three cross sections of the Powder River at Arvada, Wyo. 

v~ 

280 
"" (A 

99.9 

99.8 

99.5 

99.0 

98 

95 

90 

a:: 

taJ 80 

z 

-

LL 70 

t- 60 

z 

~50 

a:: 

taJ 40 a.. 

30 

20 

10 

5 

2 L_ __ 

I 

0.01 

- -- --

~ ~ 

~ ~ 

~ 

/ v 

/ v 

/ 

/' 

L 

/ 

/ Note: Dry sieve Ro- top analysis. f---

/ Curve is mean of 20 samples. 

/ 

v I 

/ 

v 

'------ ---------------- ---

0.1 1.0 10.0 

DIAMETER IN MILLIMETERS 

Figure 29.--Bed-material size analysis, Powder River, Wyo. and Mont. 
44 

The units were assigned for convenience, as the formula is not dimensionally correct. ll was evaluated (fig. 30) as 20,000 on the basis of data from the Niobrara and Middle Loup 

Rivers in Nebraska. 

Rates of bed-load discharge as computed 

from this formula for five different water 

discharges are shown in table 8 and are plotted against water discharge in figure 31. 

Schoklitsch's Formula 

Shulits (1935, pp. 644-646, 687) presented 

the Schoklitsch bed-load formula as follows: 

G 

- BD 

s 1 •5 (Q - o.00532 ~> 

in which G = bed load in pounds per second 

D = median diameter of the particles in inches 

S = slope of energy gradient 

B ~ width of stream in feet 

Q = water discharge in second feet 

This formula was developed by analyzing 

data from flume experiments in which the bed 

material was uniform quartz grains. A minimum 

fluid force is assumed to be necessary to 

start particle movement. This formula was cho- sen for its simplicity and because it ~ontains 

no constants that must be evaluated by data 

from other streams. 

The rates of sediment discharge as bed load 

at four different rates of water discharge were computed and are listed in table 8. Rates 

of sediment discharge are plotted against wa- ter discharge in figure 31. 

Einstein's Formula 

Einstein (1950) approached the problem of 

bed-load movement by a method different from 

that used by most investigators. He combined 

certain variables into dimensionless expressions for the probability that a given parti- cle would be moved from its position in the 

bed surface. He developed a formula to com- pute the total sediment discharge of bed-load 

material, the material that is transported 

either in suspension or as bed load and that ha~ particle sizes within the range of sizes 

that are found in significant quantities in 

the stream bed. The formula is complex, and 

its solution requires supplementary graphs 

for evaluating integrals and for determining 

other quantities that are included in the formula. A part of the formula can be used to 

compute bed-load. discharge. However, the bed 

load as defined by Einstein (1950, p. 4) is 

not the same as the bed load as defined on page 22 of this report. His definition seems to limit the bed load to bed material that 

moves in a layer immediately above the stream 

bed and only two particle diameters thick. 

Rates of bed-load discharge were computed 

with the Einstein formula for three different 

water discharges. The computed discharges of 

sediment as bed load are shown in table 8 and are plotted on figure 31. 

Figures of bed-load discharge (table 8) as computed by the three different formulas are not directly comparable. The constant of the 

Du Boys formula was evaluated from bed-load 

discharges that were computed as the differ- ence between total sediment discharge and 

suspended-sediment discharge as measured by 

the Geological Survey. Thus the Du Boys formula as evaluated should give bed-load discharges that can be added to suspended-sediment discharges to compute total sediment 

discharge. According to Shulits (1935, p. 645), 

Schoklitsch1 s formula computes "that portion 

of the total solids load of a river which is 

transported (not in suspension) along the riv- er bed by the tractive force of the stream." 

Bed-load sediment discharge as computed by 

the Schoklitsch formula should be approximately the same as the difference between suspended-sediment discharge as measured by the Geological Survey and total sediment discharge 

of a stream. Only a part of Einstein's formula was used, and the bed-load discharge com- puted with it should, by definition, be only 

the discharge of material that moves in a layer two particle diameters thick and just 

above the stream bed. As Einstein's formula 

is based on a definition of bed load that differs widely from the definition that is used 

in this report, average annual discharge of 

bed load was not computed with his formula. 

The Geological Survey measures suspended 

sediment with samplers that do not collect 

water-sediment mixture within about 0.3 ft of 

the stream bed. Hence measured suspended-sediment concentr·ations tend to be slightly low 

because ·the concentration of suspended sediment near the bottom of a stream is usually 

higher than the average concentration of the 

stream. However, except for shallow depths, 

the error is negligible, and bed-load discharge computed from a formula like 

Schoklitsch 1 s can be added to the measured 

discharge of suspended sediment to obtain total sediment discharge. 

Gilbert (1914, p. 11) concluded that the 

capacity of a stream to transport sediment as bed load varies on the ~verage with the 3.2 

power of the mean velocity if the slope is 

constant. The computed discharges of bed-load 

sediment (table 8) increase as approximately 

the 2.8 power of the velocity. As Gilbert 

found a range of about 2.0 to 5.0 in the pow- er of the velocity, the bed-load discharges 

of table 8 are considered to be in good agreement with Gilbert's conclusion as to the change 

in discharge of_ bed-load sediment with velocity. 

Table B.--Computed rates of_discharge of bed-load sediment for the Powder River at Arvada, Wyo. 

Water discharge Average velocity Bed-load discharge, in tons per day 

(cfs) (ft per sec) Du Boys Schoklitsch Einstein 

20 0.69 24 • • • •• :1 •••••••••••• .................. 100 1.38 91 36 .................. 400 2.23 500 398 :331 

3,000 5.82 3,580 3,620 4,210 

12,000 8.29 19,500 14,800 13,900 
10 

6 

~ q = 2x 10

4 

s d 3/4 (yS)2 - ......:... -.S"" --y v 

4 

2 

/ 'I 

c 0/ 

0 v 0 0 

q, 

0 y 0 c 

0 c 

0 

~ ~ 8 

c ~ 

•/c ~0 .A 

~~. 0 oro 

/. 

v • 

• 0 ( 

/ • • o Niobrara River near Cody, Nebr. 0 • • Middle Loup River near Dunning, Nebr . • 

0.6 

0.4 

0.2 

0.1 

0.06 

0.04 

Q02 

• 

QOI 

2 4 6 10 20 40 60 100 200 

2 

(yS) XI06 

d3/4 

Figure 30.--Comparison of bed-load data from the Niobrara and Middle Loup Rivers in Nebraska 

2 X 104 

with equation q8 = d! (ys)2. 

45 
100,000 

50,000 

~ 10.000 

0 

u 

~~ 

/L 

1,~ 

~., 

taJ ,, en 5000 a: 

~ ~ 

/~ 

taJ 

Q. /' 

~ :.1 

1-

taJ 

taJ 

'? - / v lL 

~ 

m 

:::l 

u 1000 

,;} ~ , / 

SCHOKLITSCH / 

/ 

~ I ;It 

~ .""-. 

w'" 500 C) 

a: 

<I 

J: 

u 

en 

0 

,~ DU BOYS 

1- /. ~ 1-, ~~ v 

v/ ~, 

a: 

taJ 

..... 

<I 

~ 100 

, v // EXPLANATION 

.... v// Bed -toad equations: 

- ~ 

I' Du • Boys 

50 • ./'~. Einstein 

1"'/ .. ./ Schok litsch 

/ ~// 

/_ 

'/ -

10 

10 50 100 500 1000 5000 10,000 50,000 

BED-LOAD DISCHARGE, IN TONS PER DAY 

Figure 31.--Relation o~ bed-toad discharge to water discharge, Powder.River at Arvada, Wyo. 

46 
Sediment Discharged Annu,lly as Bed Load 

The relationship between water discharge 

and-bed-load discharge as computed with the 

Du Boys'. and Schokl1tsch1 s formulas can be 

represented fairly well by straight lines on the logarithmic scales of figure 30. The 

slopes of the lines indicate that the bedload discharge increases as about the 1.05 or 1.10 power of the water discharge. The sus- pended-sediment discharge increases approximately as the square of the water discharge. 

(See fig. 17.) Thus the ratio of bed-load discharge to suspended-sediment discharge de- creases rapid~y with increase in water discharge. 

The straight-line relationships defined by 

bed-load computations that were made with the 

Du Boys' and Schoklitsch's formulas were used 

to compute annual discharge of sediment as bed load for the Powder River at Arvada. The 

flow-duration curve covering 33 yr of streamflow records of the Powder River at Arvada 

(fig. 14) was used to define the percentage of 

time that the flow was within each of 19 class 

intervals of flow. Bed-load discharges corre- sponding to the middle water discharge of each 

class interval of flow were taken from the 

straight lines of figure 31. The products of 

these· bed-load discharges and the percentages 

of time when the flow was within each interval were added, and the sum was divided by 100 to 

obtain average annual discharge of sediment as bed load. Bed-load discharge per year was also computed for the 4-year period that ended 

September 30, 1950, from a duration curve of 

water discharge for this 4-year period. All 

the computed average annual discharges of sediment as bed load are shown in table 9. The 

average specific weight of bed-material sam- ples from the Powder River basin (table 32) was about 90 lb per cu ft. This specific 

weight was used to change the tonnage of bedload discharge per year to yearly volume of 

bed-load sediment after deposition in a rea- ervoir. 

Table 9.--Computed annual discharge of bedload sediment, Powder River at Arvada, Wyo. 

Average annual discharge of 

bed-load sediment 

Bed-load 33-year period 4-year period fqrmula Acre- Acre- Tons feet Tons feet 

Du Boys .••••• 190,000 98 140,000 70 

Schokli tach •• 160,000 82 110,000 58 

The bed-load discharges computed from Du 

Boys' formula agree reasonably well with 

those computed from Schoklitsch1 s formula. According to these formulas, the discharge of 

sediment as bed load (table 9) amounts to on- ly about 175,000 tons per yr on the basis of 

the water discharge during the p~riod of 

stream-flow records for the Powder River at 

Arvada and about 125,000 tons per yr on the 

basis of the water discharge for a 4-year period that ended September 30, 1950. During the 

4-year period, the computed discharge of bedload sediment was only 2.2 percent of the sus- pended-sediment discharge by weight and 1.4 

percent by volume after deposition in a res- ervoir. ~ 

47 

Sources of Sediment Transported by the Powder 

River 

Rates of erosion vary widely within the 

Powder River drainage basin. Major sources of 

sediment, areas where rates of erosion are high, can be correlated with different factors such as topography, vegetative cover, 

type of runoff, or types of rocks that underlie an area. Perhaps the large areas with 

high rates of erosion can best be delineated on the basis of the kinds of the underlying rocks. 

Unfortunately, the sediment records during the spring and summer of 1950 are not representative data. As figure 13 shows, the water 

discharge for the water year ending September 

30, 1950, was close to the lowest annual discharge for the period that is covered by · stream-flow records. Presumably, the suspended-sediment discharge for 1950 was far below 

the average annual sediment discharge. Hence 

the available records of suspended-sediment 

discharge must be used with caution in delineating the major source areas of sediment 

that is transported by the Powder River. 

Areas Underlain by Paleozoic and Pre-Cambrian 

Rocks 

In ·the Powder River drainage basin the 

streams draining areas that are underlain by pre-Cambrian and Paleozoic rocks are clear 

streams in relatively stable channels. They are typical mountain streams transporting little sediment either in suspension or as bed 

load. High flows are seasonal and ar~ caused . mostly by snow melt. Some of the channels are in deep canyons, but the present rate of ero- sion in these canyons is slow. The areas un- derlain by Paleozoic and pre-Cambrian rocks are in the Bighorn Mountains except for a very small area in the Rattlesnake Range. 

(See fig. 5.) These areas are an insignificant source of the sediment that is transported by 

the Powder River. 

Areas Underlain by Mesozoic Rocks 

As the streams leave the mountains and en- ter the areas that are underlain by Mesozoic 

rocks, they begin to erode their channels more actively and soon become discolored with 

sediment. The Middle Fork Powder River is a good example of a mountain stream that begins 

to carry appreciable quantities of sediment 

after flowing for a few miles across an area that is underlain by Mesozoic rocks. Much of 

the sediment carried by the Middle Fork above 

Kaycee is derived from the channel, but during periods of storm runoff the minor tributaries that drain areas underlain by Mesozoic 

rocks discharge significant quantities of sediment that were eroded from the land surface 

and from ephemeral stream channels. 

A large part of the sediment transported by 

the Powder River is contributed by streams 

whose drain~ge areas are almost completely 

underlain by Mesozoic rocks. The largest of 

these streams (fig. 5) are Salt Creek and the 

South Fork Powder River. (A very small area at the.. source of the South Fork is underlain 

by Paleozoic rocks, and a small percentage of 

the drainage area farther downstream is underlain ~y Tertiary rocks.) Both these streams 
48 

have high concentrations of suspended sediment as is shown by the sediment record for the 

South Fork near Kaycee and by the large in- crease in sediment discharge from the stations on the Middle Fork near Kaycee and on the 

South Fork near Kaycee to the station on the 

Powder River near Sussex. Although part of 

this increase. is due to scour of the channels betwe~n these stations, most of the increase 

during and following periods of storm runoff 

is due to the sediment that is discharged by 

Salt Creek and small streams. The sediment 

transported by Salt Creek and nearby small, 

intermittent streams is derived oy sheet and 

rill erosion, channel scour, and gully cutting. (See p. 15 and fig. 8.) 

Records of suspended-sediment discharge for 

the South Fork Powder River are much too short 

to show adequately the high rates of sediment 

discharge that may occur. The records summa- rized in tables 4 and 14 cover only periods 

of relatively low flow and correspondingly 

low concentrations of suspended sediment. Suspended-sediment samples were collected on May 

3, 6, and 11 outside the period of daily rec- ords. The concentrations of the samples together with estimated water discharges indicate an average suspended-sediment discharge 

of 50,000 tons per day for these 3 days. In 

contrast, the total sediment discharge from 

May 17 to September 30, 1950, was 76,640 tons. 

The effects of fairly rapid rates of ero- sion can be seen in most of the areas that are underlain by Mesozoic rocks, but the fastest rates of erosion probably occur in bad~ 

land areas, at gullies that are actively eroding (fig. 8), and at stream meanders. The eas- ily eroded soils, valley alluvium, and friable 

rocks of the areas that are underlain by Mesozoic rocks, plus the relatively steep land 

slopes and sparse vegetation, make these areas a major source of the sediments that are transported by the Powder River. 

Areas Underlain by Tertiary Roc~s 

More than half of the Powder River drainage 

basin is underlain by Tertiary rocks. These . rocks underlie most of the basin north of 

Sussex, Wyo., and outside the·mountains ex- cept for an area east and northeast of Little 

Powder River that is underlain by Mesozoic 

rocks. 

Clear Creek and its major tributaries are clear mountain streams when they enter the area that is underlain by Tertiary rocks. As 

they flow across this area, they begin to 

pick up small amounts of sediment from their 

channels, which are mostly boulder-lined and are fairly stable. During periods of storm 

runoff, the tributaries draining this area discharge sediment into the perennial streams, 

but the concentration of suspended sediment 

at the mouth of Clear Creek near Arvada nor- mally is low. It averaged less than 500 ppm 

for the few months of suspended-sediment rec- ords during 1950. (See tables 4 and 21.) 

The tributaries of Crazy Woman Creek transport very little sediment until they leave 

the mountains and flow across a narrow area that is underlain by Mesozoic rocks, where 

they begin to pick up a noticeable amount of 

sediment. Soon after leaving this narrow area, 

the tributaries join to form Crazy Woman 

Creek, which flows for its entire length across an area that is underlain by Tertiary rocks. Crazy Woman Creek has progressively 

higher concentrations of suspended sediment 

toward its mouth. Some of the sediment comes from the channel, some from return flow from 

irrigation, and some from small tributaries. 

Except during periods of runoff from intense 

rains, only a small tonnage of suspended sediment is discharged into the Powder Rive~ by 

Crazy Woman Creek. (See table 4.) 

The only meas~re of suspended sediment 

yields from much of the area that is underlain by Tertiary rocks is the increase in the 

sediment discharge of the Powder River from 

Sussex downstream. From March 1 to September 

30, 1950, the suspended-sediment discharge of 

the Powder River was nearly three times as large near Locate as at Sussex. Almost all 

the increase in sediment from Sussex downstream was derived from the general areas that are underlain by Tertiary rocks. Specifically, a large part of the increase probably came from Quaternary alluvium along the channel. At least during the water year that ended September 30, 1950, the sediment yield 

from the areas that are underlain by Tertiary 

rocks was greater than the sediment yield of 

all other parts of the Powder River drainage 

basin, largely because of the size of these areas. The rate of erosion may not have been as high from the areas that are underlain by 

Tertiary rocks as from those that are ~darlain by Mesozoic rocks. 

CHEMICAL QUALITY OF THE WATER 

Plan of Study 

The chemical quality of water in the Powder 

River and its tributaries is defined from the 

analyses of 127 samples that were collected 

in the period November 1945 to September 1950. 

Main stem stations and the Middle Fork Powder 

River were sampled approximately monthly, 

whereas other tributary stations were sampled 

about once every 3 months. During the period 

September 10 to 14, 1949, samples were collected at 29 points for chemical analysis in 

connection with a basin salinity study of low 

flows. Records of sampling are shown in the 

following table: 

Station operation_ records 

Station 

Powder River at Sussex, Wyo •••••••••.•••• Powder River at Arvada, Wyo •••••••••••••• Powder River near Locate, Mont ••••••••••• 

a Approximate figure. 

Drainage area 

(square 

miles) 

Field-sampling program 

Period of collection !Approximate schedule 

Nov. 1949 to Sept. 1950 

May 1946 to Sept. 1950 

Nov. 1945 to Sept. 1950 

Monthly. Do. 

Do. 
49 

Station operation records--Continued 

Drainage Field-sampling program 

Station area Number I (square of 

miles} samples 

Period of collection ~A~proximate schedule 

Tributaries 

Middle Fork Powder River near Kaycee, 

Wyo ••••••.•••••••••••••••••••••••• • • • • 980 

Crazy Woman Creek near Arvada, Wyo •••••• 956 

Clear Creek near Buffalo, Wyo ••••••••••• 120 

Clear Creek near Arvada, Wyo •••••••••••• 1,110 

Basin salinity study •.••••••••.••••••••• a 13,400 

a Approximate figure. 

A plan of study was selected that would furnish analytical data at key stations on the 

Powder River and its major perennial tributaries. The stations on the main stem at 

Sussex, Arvada, and Locate (fig. 32) provide 

information on the chemical character of the 

river water along a course of about 318 miles. 

Stations on tributary streams were installed 

at points close to the confluences of these 

tributaries with the Powder River. Analyses 

9f samples of water from a tributary stream near its mouth show the quality of the water 

that is leaving the drainage basin. The location of sampling points was coordinated with 

the needs of planning agencies for information on the quality of water that may be impounded for irrigation. 

The determinations of specific conductance, 

percentage of sodium, and boron were made for 

stations where samples were taken regularly, as these measurements have a direct bearing on the rating or classification of irrigation 

water. Silica, iron, calcium, magnes~um, so- dium and potassium, bicarbonate, sulfate, 

chloride, fluoride, and nitrate were also re- ported, together with pH and hardness, as these constituents and properties affect the 

suitability of the water for general use. Tables 33 and 34 show chemical analyses and 

water discharges. 

Composition of River Water 

The composition of a river water is dependent primarily upon the geological formations 

that are traversed, and it varies with time 

and place. River water is thus in unstable 

equilibrium and is undergoing continuous 

25 May 1946 to Sept. 1950 Monthly. 

5 Dec. 1949 to Sept. 1950 Tri-monthly. 

4 Dec. 1949 to Sept. 1950 Do. 

5 Dec. 1949 to Sept. 1950 Do. 

29 Sept. 10 to 14, 1949 ............ 

change by chemical reaction of various kinds. 

The rivers carry the weathering products in 

the form of ionic solutions or as colloidal 

dispersions. The amount of these materials 

varies according to the climate and to the 

chemical composition and physical properties 

of rocks and soils in the catchment area. Clarke (1924, p. 69) points out that a river 

water is the average of all its tributaries 

plus the influence of rain and ground water. 

Geochemistry of the Basin Waters 

The varied geology and topography of the 

Powder River drainage basin cause wide fluctuations in both composition and salinity of 

the waters in the basin. Clear Creek, which 

has its source in the Bighorn Mountains, 

flows for several miles through a region of 

pre-Cambrian granites. Near Buffalo, Wyo., this stream has the chemical characteristics 

of a typical mountain water; the mineral con- tent and hardness are low, and bicarbonate 

exceeds sulfate. The Little Powder River, on the other hand, heads in upland country and 

drains an area that is largely underlain by 

Tertiary sandstones and shales. Water from 

the Little Powder River near Broadus, Mont., 

has high mineral content and hardness and con- tains much more sulfate than bicarbonate. The 

percentage composition of the mineral solids 

in several waters that have been in contact 

with principal rock 'types is shown in table 10. 

It is seen from table 10 that the granitetype water in Clear Creek near Buffalo, Wyo., is a calcium carbonate water of low mineral 

content, and that silica composes much of the 

mineral solids. The limestone-type water is 

Table 10.--Percentage composition of waters that drain from principal rock types, Powder River 

drainage basin 

Mineral constituent Granite-we 

water 1 

Silica (Si02) •••••••••••••••••••• 27.6 

Calcium ( Ca) ••••••.•••••••••••••• 23.2 

Magnesium (Mg) •••.••••••••••••••• 2.2 

Sodium and potassium (Na + K) •••• 1.2 

Carbonate (C03) •••••••••••••••••• 37.0 

Sulfate ( S04) •••••••••••••••••••• 7.4 

Chloride and nitrate (Cl + N03). • 1.4 

Total •••••••••••••••••••••• 100.0 

J?issolved solids (ppm) ••••••••••• 43 

1/ Clear Creek near Buffalo, Wyo. gj Middle Fork Powder River near Barnum, Wyo. ~/ Middle Fork Powder River above Kaycee, Wyo. j/ Little Powder River near Broadus, Mont. 

Limestone~pe Gypsum-we Shale-type 

water 2 water 3 water y 

6.4 1.4 0.3 

20.4 16.7 6.9 

10.8 5.5 3.8 

1.2 7.6 20.3 

54.6 14.0 8.1 

3.6 52.8 60.0 

3.0 2.0 .6 

100.0 100.0 100.0 

158 727 2,020 
EXPLANATION 

Schedul! s;ation 

Basin salinity • study 

10 30 Miles ~~~----~----~--~ 

0 

0 SHERIOAN 

0 CASPER 

106" 

oEkoloko 

Index mop of Montano and WyominQ 

showing the Pow~er Rive; drainage basin 

Figure 32.--Map o:f the Powder River drainage basin in Wyoming and Montana, showing chemicalquality stations. 

50 
a calcium carbonate water of moderate concen- tration but contains less silica and more magnesium than the granite-type water. The Middle 

Fork Powder River near Barnum, Wyo.,, drains an area that is underlain by the limestones in 

the Phosphoria and Madison formations and.by the porous Bighorn dolomite. Downstream in 

the vicinity of Kaycee the river water has 

been altered in chemical character from a limestone-type to a gypsum-type (CaS04•2H20) 

water. This change occurs because the river crosses an area that is underlain by gypsum beds, gypsiferous shales, and siltstones. A 

typical shale-type water is illustrated by 

the water in the Little Powder River near Broadus, Mont. This water contains considerable amounts of sodium sulfate that have been 

leached ~rom Tertiary -and Cretaceous shales 

and sandstones above Broadus. The composition 

of several waters in the basin is shown graphically in figure 33, in which cumulative percentages of the major mineral constituents are plotted. 

Many of the basin waters are mixtures of 

those characteristic of two or more rock 

types. An example of a mixed type is the wa- ter in North Fork Crazy Woman Creek above 

Billy Creek, near Bu~falo. This stream has its headwater~ in pre-Cambrian granites and flows 

successively over Paleozoic limestones and 

dolomites and over an area that is underlain 

by Cretaceous shales. The composition of this 

creek water at the bridge on United States 

Highway No. 87 near Buffalo is as follows: 

Silica (Si02)..................... 9.7 

Calcium ( Ca). • • • • • • • • • • • • • • • • • • • • • 16.8 

Magnesium (Mg).................... 5.7 

Sodium and potassium (Na + K)..... 7.7 

Carbonate (C03)................... 32.9 

Sulfate (S04)•••••••••••••••••i••• 25.8 

Chloride and nitrate (Cl + N03)... 1.4 

Total •••.••.••.••••••••••••• 100.0 

Dissolved solids (ppm) •••••••••••• 155 

In the above analysis it is seen that both 

carbonate and sulfate are present in significant amounts. Also, the percentage of silica · is intermediate between that present in a granite water and that reported for a limestone water. 

51 

Table ll lists the percentage compositions 

of 27 water samples that were collected at 

low flows in connection with a salinity study 

in the Powder River basin. 

Chemical Quality and Stream Discharge 

The chemical quality of water in a flowing 

stream varies from day to day or from hour to 

hour depending upon the stage o~ the stream. 

As a general rule, the salinity of a river 

water is highest during periods of low water 

discharge and lowest during per~ods of high runoff. This is so because the low or base 

flqw o~ the st~eam is sustained by groundwater inflow that has leached the soluble minerals of rock and soil particles in reaching 

the stream. At high stages and during floods 

the salt concentration of the base flow is diluted by snow melt or surface runoff,. and the 

resultant solution is much less concentrated. 

An exception to this normal occurrence is observed on occasions when a rise in stage is 

localized in a tributary stream, and the main 

stem remains practically unaf~ected. The r~­

duction in salinity of the tributary water 

may not be sufficient to offset materially the concentration of salts in the primary 

stream. 

Analyses of water in the Powder River and 

its tributaries at discharges that approximate the mean for the period of record are shown graphically, in equivalents per million, 

in figure 34. Weighted average analyses for 

main stem and tributary waters are not shown 

inasmuch as daily or subdaily samples were not collected. The calculation of weighted 

values that are based on monthly or quarterly sampling is not possib:e. 

Powder River Main Stem 

From Sussex, Wyo., to its confluence with 

the Yellowstone River near Terry, Mont., the 

Powder River meanders over a course of approx- imately 350 miles. A study of the quality of 

water in the main stem of the Powder River 

at low stage was made during the period September 11 to 14, 1949, and these results are reported in the following table: 

Quality of the Powder River water at low flow 

Distance Date Daily mean Tons per acre-foot 

Station downstream from September discharge Dissolved Sussex, Wyo. Sulfate solids (miles) -

Sussex, Wyo ..•••••.•••• 0 

Arvada, Wyo .••••••••••• 119 

Moorhead, Mont •..••.••• 165 

Broadus, Mont ••• · ••••••• 212 

Locate, Mont •••••.••••• 318 

Mouth ••.•.••••••••••••• 350 

In all reaches of the river the amount of 

sulfate in the water exceeded 50 percent Of 

the total mineral content and ranged from 53 

percent at Sussex to 60 percent at the mouth. 

The increase in the concentration of dissolved 

solids at the Arvada station was due partly to 

discharges from Crazy Woman Creek, about 12 mil~s upstream, and partly to accretions from 

other sources between Sussex and Arvada. The decr~ase in salinity at Moorhead is explained 

by the discharge of less concentrated water 

from the mouth of Clear Creek. At Locate the 

1949 

11 

12 

13 

13 

14 

14 

(cfs) 

............ 2.49 1.31 

2.0 3.17 1.85 

54 1.54 .89 ............ 1.65 .97 

44 2.00 1.20 ............ 2.19 1.32 

salinity of the-water again increases, largely as the result of salt contribution from 

the Little Powder River. The composition of 

the main-stem water is shown graphically in 

figure 35. 

The variation in salt concentration with 

discharge during the 12-month period that ended September 30, 1950, is shown for the 

Sussex, Arvada, and Locate stations in figures 

36 to 38. 
EXPLANATION 

Clear Creek near • Buffalo, Wyo. 

---<>- Piney Creek at Kearney, Wyo. 

Middle Fork Crazy Woman ' Creek near Greub, Wyo. 

. ---o--

Poison Creek near Greub, Wyo. 

• • Powder R•ver at Sussex, Wyo. 

0~----------~----------~----------~----------~----------~--------~ 

Silica Calcium Magnesium Sodium Carbonate Sulfate Chloride 

and Potassium 

Figure 33.--Cumulative percentage composition of water from several streams. 

52 
Table 11.--Percentage composition of water in the Powder River drainage basin during low flow 

Station 

South Fork Powder River near Kaycee, Wyo ••• Powder River at Sussex, Wyo ••••••••••.•••.••• Powder River at Arvada, Wyo •••••••••••••••• Powder River at Moorhead, Mont ••••••••••••• Powder River near Broadus, Mont •••••••••••• 

Powder River near Locate, Mont ••••••••••••• Powder River at mouth near Terry, Mont ••••• Middle Fork Powder River near Barnum, Wyo •• Middle Fork Powder River above Kaycee, Wyo. Middle Fork Powder River at Kaycee, Wyo •••• 

Middle Fork Powder River near Kaycee, Wyo •• Beaver Creek near Barnum, Wyo •••••••••••••• Red Fork near Barnum, Wyo •••••••••••••••••• North Fork Powder River near Mayoworth, Wyo 

North Fork Powder River near Kaycee, Wyo ••• 

Salt Creek near Sussex, Wyo •••••••••••••••• North Fork Crazy Woman Creek above Billy Creek, near Buffalo, Wyo ••••••••••••••••• North Fork Crazy Woman Creek below Middle 

Fork near Buffalo, Wyo ••••••••••••••••••• 

Crazy Woman Creek near Buffalo, Wyo •••• ~··· 

Middle Fork Crazy Woman Creek near Greub, 

Wyo •••••••••••••••••• • •• • • • • • · • • • • • • • • • • • Poison Creek near Greub, Wyo ••••••••••••••• South Fork Crazy Woman Creek near Greub, 

Wyo • ••••••••••••••••• •. • • • • • • • • • • • • • • • • • • 

Clear Creek near Buffalo, Wyo •••••••••••••• Clear.Creek near Arvada, Wyo ••••••••••••••• Piney Creek at Kearney, Wyo •••••••••••••••• Lake De Smet, Wyo •••••••••••••••••••••••••• Little Powder River near Broadus, Mont ••••• 

Silica 

(Si02) 

o.s 

.5 

.3 

.5 

.7 

.7 

.6 

6.4 

1.4 

1.1 

.6 

2.0 

2.5 

2.4 

.7 

.2 

9.7 

1.7 

.5 

5.3 

.5 

1.6 

27.6 

.5 

9.6 

1.4 

.3 

Calcium 

(Ca) 

11.7 

12.5 

10.2 

11.2 

10.3 

9.4 

9.6 

20.4 

16.7 

12.7 

12.4 

14.8 

15.2 

13.4 

9.4 

6.9 

16.8 

12.6 

11.0 

20.9 

14.3 

11.1 

23.2 

11.3 

24.5 

7.6 

6.9 

Magnesium (Mg) 

2.8 

4.2 

4.2 

7.4 

6.6 

5.4 

4.4 

10.8 

5.5 

5.2 

4.9 

7.0 

7.5 

6.4 

5.2 

3.0 

5.7 

7.4 

7.2 

6.3 

4.4 

6.8 

2.2 

7.6 

6.1 

6.3 

3.8 

Sodium and 

potassium 

(Na + K) 

16.8 

14.0 

15.8 

10.2 

12.2 

15.0 

16.1 

1.2 

7.6 

12.6 

13.5 

6.9 

9.0 

10.1 

15.2 

21.1 

7.7 

8.9 

10.1 

3.0 

10.3 

11.9 

1.2 

9.6 

.8 

16.2 

20.3 

Carbonate 

(C03) 

4.1 

5.4 

3.9 

11.6 

10.2 

8.3 

7.5 

54.6 

14.0 

10.2 

10.2 

14.0 

29.5 

21.2 

8.5 

3.9 

32.9 

14.7 

7.8 

28.1 

3.9 

16.7 

37.0 

10.0 

45.4 

14.3 

8.1 

Sulfate 

(S04) 

52.1 

52.5 

58.4 

58.1 

58.9 

59.6 

60.0 

3.6 

52.8 

49.9 

51.2 

54.4 

29.5 

46.3 

59.4 

60.8 

25.8 

53.8 

62.3 

35.8 

65.8 

51.3 

7.4 

60.1 

12.3 

52.8 

60.0 

Chloride 

and nitrate 

(Cl + N03) 

11.7 

10.9 

7.2 

1.0 

1.1 

1.6 

1.8 

3.0 

2.0 

8.3 

7.2 

.9 

6.8 

.2 

1.6 

4.1 

1.4 

.9 

1.1 

.6 

.a 

.6 

1.4 

.9 

1.3 

1.4 

.6 

Dissolved 

solids 

(ppm) 

1,950 

1,830 

2,330 

1,130 

1,210 

1,470 

1,610 

158 

727 

1,010 

1,090 

845 

387 

623 

1,660 

3,750 

155 

754 

1,380 

302 

3,250 

881 

43 

1,170 

114 

698 

2,020 

(J1 

~ 
EXPLANATION 

Sodium + Potassium Calcium Sulfate 

Magnesium Chloride + N itr~te Carbonate + Bicarbonate 

22--------------------------------------------------------------------~ 

18 f--

161--

ffi 12 

0.. 

A Powder River at Sussex, Wyo., 115 cfs, March 3, 1950. 

B Powder River at Arvada, Wyo., 261 cfs, April 4, 1947. 

C Powder River near Locate, Mont., 288 cfs, July 17, 1950. 

D Middle Fork Powder River near Kaycee, Wyo.~ 145 cfs, April 6, 1950. 

E Crazy Woman Creek near Arvada, Wyo., 57 cfs, July 5, 1950. 

F Clear Creek near Buffalo, Wyo .. , 332 cfs, June 6, 1950. 

G Clear Creek near Arvada, Wyo., 86 cfs, December 7, 1949. 

Figure 34.--Graphical analyses or water in the ¥owder River and tributaries. 

54. 
Sussex Arvada Moorhead Broadus Locate Mouth 

2500.---------.----------.--~-----,.--.------,-~------~----------~-,~--~ 

z 

0 

::; 1500 

,_1 

i 

a: 

r 

~ cr:: 

<( 

0-

200 250 300 350 

MILES SUSSEX, WYO., TO MOUTH 

V///1 

Chloride, Nitrate, and Fluoride Sulfate 

Carbonate Sodium and Potassium Calcium and Magnesium 

Figure 35.--Composition of the Powder River water at low stage, Sept. 11 to 14, 1949. 
1600 

I 0 1400 

z 

0 

u 

&&I 

en 

0: 1200 .. &&I 

CL. 

.... 

&&I 

~ 1000 

u 

~ ~ 

I 

iii 

::::> 

u 

~ i 800 v &&I 

<:) 

0: 

"' ::1: 600 u 

en 0'1 iS 0'1 

z 

"' w 400 

~ 

c 

0 200 

~ 0 

4.0 

AA ~ 

A 

!v v~J \Avt ~ .~ -- ~~~ \ ~ .... ~ 

1&1 

0:: 

u 

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r 

~ 2.0 

I 

I 

i 

~ 

en 

g 

.J 

~ LO 

0 

&&I 

a 0 en 

0 

I 

I 

I I 

I 

I 

OCTOBER , NOVEMBER DECEMBER JANUARY FEBRUARY MARCH APRlL MAY JUNE JULY AUGUST SEPTEMBER 

Figure 36.--The relation between discharge and concentration, Powder River at Sussex, Wyo., 1949-50. 
01 

"" 

0 

Z" 

1600 

0 1400 :rl 

U) 

a:: 

0. "'1200 1-

"' "' Ia. 

~ 1000 :::::1 

u 

~ 

"' (!) 

a:: 

cr 

:t: 

u 

U) 

0 

z 

cr 

"' 2 

~ 

~ 

~ I 

~ 

r 

~ ~ 

~ a 

i 

800 

600 

400 

200 

0 

3.0 

2.0 

1.0 

0 

1Y 

OCTOBER 

1 1820 

-=~=--

AA" r \J\ ~ vv v" 

~ -

V\ ~ N \ - _A ~ 1\J"--- ~ ,. 

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH APfiU .. MAY .JUNE JULY AUGUST SEPTEMBER 

Figure 37.--The relation between discharge and concentration, Powder River at Arvada, Wyo., 1949-50. 
3000 

2800 . . 

~ 

C) 

z § 2400 

U) 

0:: 

"' G. 2000 ... 

"' "' 

~ 

' II. 

u iD 1600 ;:) 

u 

!: 

"' t2.00 (!) 

0:: 

C"· 

% 

u 

U) 

0 800 

z 

c 

~A . ~ . -~ \j 1~ ~~ ,; - ~ l 

"' CTI a (I) ~ 400 

~ 

0 

~J 

/ "" .a. -

'J~ _fl\.._ . --- ~ 

~ 4.0 

I 

~ c 

:a: 3.0 

~ 

, 

J 2.0 : 

i! 

s 

51 1.0 

e 

~ 0 ----- I I I U) 

0 OCTOBER NOVEMBER DECEMBER JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER 

Figure 38.--The relation between discharge and concentration, Powder River near Locate, Mont., 1949-50. 
Tributaries 

Chemical analyses (tables 33 and 34) for 

the tributary stations--Middle .Fork Powder 

River near Kaycee, Crazy Woman Creek near Arvada, Clear Creek near Buffalo, and Clear 

Creek near Arvada--show the normal concentration-discharge pattern. In general, the periods of high runoff correspond with periods 

59 

of lower salinity, and days of low flows are associated with intervals of higher salinities. These relationships are plotted graphically in figures 39 to 42. 

The concentrations of dissolved solids and 

sulfate in low flows were determined for tributaries to the Powder River and are reported in the following table: 

Quality of tributary water at low flow 

Station 

I 

Middle Fork Powder River near Barnum, Wyo •••••••• Middle Fork Powder River above Kaycee, Wyo •.••••. Middle Fork Powder River at Kaycee, Wyo ••••.••••• Middle Fork Powder River near Kaycee, Wyo ••.••••• Clear Creek near Buffalo, Wyo ••..•.•.••••••••••• · Clear Creek near Arvada, Wyo ••••••••••••••••••••• 

Except for the Barnum and Buffalo stations, 

the amounts of sulfate constituted at least 

50 percent of the mineral solids in the water. 

Chemical Quality and Irrigation 

The following statements have been largely 

drawn from publications in the field of irrigation, particularly the subject of the quality of water for irrigation (Wilcox, 1948; 

Scofield, 1936; Israelsen, 1950; Chemical and 

Engineering News, 1951). 

The interpretation of the analysis of an irrigation water has been described as empirical 

in the sense that an explanation of the analysis is based on field observation, experience, 

and plant-tolerance research. It would appear 

that the rating or classification of an irrigation water under such circumstances would 

be wholly arbitrary, but the agreement among 

workers in this field is good. 

Irrigation waters contain dissolved material 

that consists principally of cations (calcium, 

magnesium, sodium, and potassium) and anions 

(carbonate, bicarbonate, sulfate, chloride, 

fluoride, and nitrate). The nature and concen- tration of the cations in a water are important, as the reactions of the cations with 

the soil determine the suitability of both 

soil and water for agricultural use. 

Calcium and magnesium tend to keep a soil 

permeable and in good tilth, whereas sodium 

produces the opposite effects. Sodium appar-

·ently increases the osmotic concentration of 

the cell sap in plants and thus retards desiccation. Also, in high concentrations the so- dium ion is toxic to plants. The percentage 

of sodium is the ratio of sodium to the total 

cations (as equivalents) in the irrigation 

water and determines the adverse effect of 

·-sodium on the soil. Potassium occurs usually 

in low concentrations in irrigation water, 

and the reaction of potassium with the soil , is similar to that of sodium, but the effects are not as harmful. However, potassium is es- sential to plant growth and is one of the ma- jor food elements. 

The effects of the anions on soils are not 

too well understood. The hydrogen ion concen- tration of the water is determined chiefly by 

carbonate and bicarbonate, which buffer the 

Date Daily mean Tons per acre-foot 

September discharge Dissolved Sulfate 1949 (cfs) solids 

10 .......... 0.21 <0.01 

10 40 1.03 .52 

10 .......... 1.37 .69 

11 12 1.48 .76 

11 20 .06 <.01 

13 62 1.59 .Q6 

water. Sulfate has no characteristic action 

on the soil other than to increase the salinity. Chloride inhibits the growth of most 

crop plants and becomes definitely toxic to 

many crops at moderate concentrations. Only 

traces of nitrate are present, as a rule, in 

surface waters, and these concentrations have 

little effect on the soil. 

With the exception of boron, the minor con- stituents in water are not of great importance 

in their relation to the soil or to plants. 

Boron, which has no noticeable effect on soil, 

is an essential element for normal plant 

growth. At concentrations only slightly above 

optimum, however, it is exceedingly toxic to 

many plants. Boron is toxic to certain plants 

when present in concentrations that are re- quired for optimum growth of other plants. 

The irrigation of some types of fruit trees 

with water of l ppm of boron causes harmful 

results, whereas the application of water of 

l to 2 ppm boron to alfalfa promotes maximum 

growth. 

The characteristics of an irrigation water 

that must be known in order to make an estimate of the quality are: the total mineral 

concentration, either in terms of electrical 

conductivity units (micromhos per centimeter 

at 25 C) or dissolved solids, in parts per 

million; the percentage of ·sodium; and the 

concentration of boron. In the interpretation of the analysis it is assumed that the water 

will be used under average con9itions as to 

soil, permeability, infiltration rate, drainage, texture, salt tolerance, climate, and 

crops. This method for the interpretation of 

water analyses is not directly applicable where unusual situations are found. It has 

been observed that the application of even an "excellent" rated water may present a salinity 

problem if drainage is poor and the .ground- . water table is less than 2 ft below the sur- race. In general, adequate drainage improves 

soil structure and increases and perpetuates 

the productivity· of soils. In connection with 

salt tolerance of crops, a water of much high- er salinity can be used in the growth of .sugar 

beets than of green beans. 

Table 12 lists the restrictions of several 

classes of irrigation water with respect to 

electrical conductivity and percentage of so- dium; table 13 shows limits of boron for crops 

of different tolerances to boron. 
0 

z 

0 

hl 

en 

0:: 

11.1 

G. 

.... 

11.1 

11.1 

~ 

u 

ii 

:;) 

u 

~ 

11.1 

" 0:: 

Cl 

:r 

u 

en 

i5 

z 

Cl Ol 

0 w 

~ 

8 

~ I 

5 

c 

t 

~ ~ 

a 

~ 

a 

~ 

1600 

1400 

1200 

1000 

800 

600 

400 

200 

0 

2.0 

us 

1.0 

Q.S 

0 

-- ~----------

k ,M J~ \ r\ ~ -~ - ..... ~ [,JIV \ .....- .....-

"" . ,r..r-

-- ~ L____----~----- I 

OCTOBER NOVEMBER DECEMBER JANUARY FEBRUARY MARCH APRIL . MAY JUNE JULY AUGUST SEPTEMBER 

Figure 39.--The .relation between discharge and concentration, Middle Fork Powder River near Kaycee, Wyo., 1949-50. 

I 
Q 

z 

8 

I&J 

en 

II: 

I&J 

Q. 

1-

I&J 

I&J 

..... 

u 

~ u 

!E 

I&J 

CD 

II: 

c 

::a: 

u en_ 

C5 0) 

I ,_, 

w 

~ 

g 

~ I 

~ II: 

~ 

~ tr 

; 

I 

400 

~50 

~0 

250 

200 

U50 

100 

50 

0 

2.0 

1.5 

1.0 

0.5 

0 

OCTOBER 

• 

~ ~ 

~ 

~ \ ' . 

V'·~ I \ 1\A v 

,~ .-/' ~ ' r'-

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER 

Figure 40.--The relation between discharge and concentration, Crazy Woman Creek near Arvada, Wyo., 1949-50. 
Q 

z 

0 

(J 

1&,1 

C/) 

a:: 

1&,1 

G. 

1-

1&,1 

1&,1 

(J "" 

iii 

:;) 

(J 

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(l) 

a:: 

ct 

::s:: 

(J 

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Q 

en z tl) ct 

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Q 

6 

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(J 

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a:: 

r 

(/) 

~ 

~ 

s 

~ 

a 

a 

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0 

400 

350 

300 

250 

200 

150 

100 

50 

0 

0.15 

0.10 

0.05 

0 

~-l' 

1...--.---------

OCTOBER 

'~ -

j 

r\ 

r 

lr l r~ \ . 

l 

A Y\J\ 

... ~ [_A ..... - - j'~ I_) ~ Lr"-1 

• 

-- - I 

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER 

Figure 41.--The relation between disc~rge and concentration, Clear Creek near Buffalo, Wyo., 1949-50. 
1290 

800 

! 9feeo 

700 0 

z 

0 

~ (I) 

a:: 600 I 

I 

1&.1 

0.. 

.... 

1&.1 

A I 

! 

1&.1 500 I&. . I 

u 

iii 

:;) 

u 

~ 400 

1&.1 

c:> 

a:: 

Oil 

I 

~ I 

\ :X JOO u 

(I) 

g: 

Q 

z 

c 

1&.1 200 2 

~ 

c 

0 100 

b 0 

6? 2.0 I 

1&.1 

l5 

c 

a:: 1.5 

~ \ I 

A ~AA,...,/\ ( ~~ v ~ ~ \l /\I ~ "' 

l~-v ..r-/ ~ v~ ~ 

I __,-

~ ~J 

.. I 

~ I 

~ 1.0 

~ 

s 

~ 0.5 

a 0 II (I) 

s OCTOBER NOVEMBER DECEMBER JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER 

Figure 42.--The relation between discharge and concentration, Clear Creek near Arvada, Wyo., 1949-50. 
64 

Table 12.--Permissible limits ror electrical conductivity and percentage of sodium ror several 

classes or irrigation water 

Classes or water Electrical conductivity Percent sodium Rating Grade (micromhos per em at 25 C) 

1 Excellent ••••••••••••••••• <250 <20 

2 Good •••••••••••••.•••••••• 250 to 750 20 to 40 

3 Permissible ••••••••••••••• 750 to 2,000 40 to 60 

4 Doubtful •••••••••••••••••• 2,000 to ·3,000 60 to 80 

5 Unsuitable •••••••••••••••• >3,000 >80 

Table 13.--Permissible limits ror boron, in parts per million, or several classes or irrigation 

water 

Classes or water 

Rating Grade Sensitive crops Semi-tolerant crops Tolerant crops 

1 Excellent ••• -•••••••• <0.33 

2 Good •••••••••••••••• .33 to .67 

3 Permissible ••••••••• .67 to 1.00 

4 Doubtful •••••••••••• 1.00 to 1.25 

5 Unsuitable •••••••••• >1.25· 

It is thought that a better classirication 

in respect to percentage or sodium is obtained 

diagrammatically. An abbreviated roru. or Wilcox's diagram is shown in figure 43 ror wa- ters in the Powder River drainage basin. Fig- ure 43 is further considered under discussion or the quality of water at individual stations. 

Powder River at Sussex, Wyo. 

Of 10 samples of water from the Powder River 

at Sussex, half would be rated as 3 (permissi- ble), and the remaining half would have ratings or 4 (doubtful) or higher. The classification is as rollows: 

Quality or water for irrigation, Powder River 

at Sussex 

Number Irrigation quality Range in daily or mean discharge samples Rating Grade (cfs) 

5 3 Permissible •• 115 to 301 

2 4 Doubtful. •••• .............. 3 5 Unsuitable ••• 11 to 109 

The water of higher numerical ratings represents sampling at periods of low water discharge when f'low in the stream consists mostly of' ground water. The river water at Sussex has 

received substantial contributions of saline 

water rrom Salt Creek. Improvement in the 

quality of' the water at Sussex is concurrent, as a general rule, with increase in"discharge, 

because the salt-laden base flows of the water 

in Salt Creek and the Powder River are then 

considerably diluted. The river at Sussex on May 6, 1950, however, discharged 608 cf's of' 

water, and this water, on the basis of electrical conductivity and percentage of' sodium, 

would be rated as 4, or doubtful as an irrigation supply. This apparent reversal in nor- mal discharge-concentration relationship may 

have resulted from \ncreased flow of' very sa- line tributary water that was discharged f'rom 

Salt Creek and the South Fork at a time when 

the river was at normal stage. The classif'ication of these waters is also shown in f'igUre 43. 

The maximum concentration of' boron that was reported was 0.30 ppm, and this low 

<0.67 <1.00 

.67 to 1.33 1.00 to 2.00 

1.33 to 2.00 2.00 to 3.00 

2.00 to 2.50 3.00 to 3.75 

>2.50 >3.75 

concentration would rate these waters as "excellent" with respect to crop tolerances to 

this element. 

Powder River at Arvada, Wyo. 

The classification of' the river water at 

Arvada indicates that most or the 27 samples 

examined have ratings of 3 (permissible) or better. These waters of better ratings corres- pond approximately to periods of higher river 

discharges. This correlation is shown in the 

f'ollowing table: 

Quality of water ror irrigation, Powder River 

at Arvada 

Number Irrigation quality Range in daily 

or mean discharge 

samples Rating Grade (of's) 

1 2 Good ••••••••• 500 

17 3 Permissible •• 90 to 2,110 

9 4 Doubtful. •••• 1.5 to 482 

It is no~eworthy that the maximum perceptage or sodium for 27 samples that were collected over wide ranges in river discharge was 48, 

but that values less than this were reported 

f'or periods or low flow. Thus, many of' the 

samples that have been classified as "doubtful" are so rated largely because of high salt 

concentrations (as indicated f'rom the electrical conductivities) and not because of unusu- ally high values f'or percentage of sodium. The 

quality or the river water at Arvada is aff'ected by tributary rlow f'rom Crazy Woman Creek, 

about 18 miles upstream. The graphical presen- tation or the classes of irrigation water appears in f'igure 43. 

Boron in the river water at Arvada presents no problem; the concentration of this element 

ranged f'rom 0.05 to 0.35 ppm and averaged 0.23 

f'or 12 samples. 

Powder River near Locate, Mont. 

Of' 22 samples that were analyzed, 18 were graded as "permissible" or better as listed 

below: 
60 

50 

:=;40 

:::> 

i5 

0 

(/) 

.,_30 

z 

UJ 

<..> 

cr 

:t' 20 

10 

• 

p 

, .... - '10 p 'i 

4 

c 0 

J 

p 

EXCELLENT 

To I 

TRIBU TARIL.=> 

~ISSIBLEl TO 

OUBTFUL 

. ""-~ 

0 

D 0 

pc 0 c 

0 0 0 

A 

•a9'i • 0 

I ' • 

DOUBTFUL 

TO 

GOOD UNSUITA~LE 

TO 

--

UNSUITABLE 

EX PLANATION 

0 

Middle Fork 

Powder River 

near 

Kaycee, Wyo. 

• Crazy Woman 

Creek near 

Arvada, Wyo. 

• Clear Creek 

near 

Buffalo, Wyo. 

A 

Clear Creek 

near 

PERMISiiBLE 

GOOD o Arvada, Wyo. 0 500 1000 1500 2000 2!500 3000 3!500 4000 

60 

50 

::E 40 

:::> 

c 

0 

(/) 

30 .... 

z 

UJ 

0 

0::: 

~20 

10 

SPECIFIC CONDUCTANCE IN MICROMHOS PER CM AT 25 C 

MAIN STEM 

~RMISSIBLE • TO 

o D~UBTFUL 

""- 0 

............... • • • 0 • 0 •o • 0( ~ 0- •o • 0 0 • 

pS • • 

• - c 

0 • • o• • 0 • • 

.o • ~0 • • oe 

• 

UNSUITABLE - • ~ 

DOUBTFUL 

TO 

GOOD • UNSUITABLE 

TO _ -.

EXCELLENT 

TOI 

GOOD 

PERMISiiBLE 

0 0 500 1000 1500 2000 2500 -3000 3500 4000 

SPECIFIC CONDUCTANCE IN MICROMHOS PER CM AT 25 C 

EXPLANATION • 

• 

Powder River 

at 

Sussex, Wyo . 

• 

Powder River 

at 

Arvada, Wyo. 

0 

Powder River 

near 

Locate, Mont. 

Figure 43.--Classification of water for irrigation use, Powder River drainage basin (modified 

after Wilcox). 
• 

66 

Quality of water for irrigation, Powder River near Locate 

Number Irrigation quality Range. in daily 

of mean discharge 

samples Rating Grade (cfs)-

1 2 Good ••••.•••• 11,100 

17 3 Permissible •. 50 to 1,630 

3 4 Doubtful. ••.• 10 to 286 

1 5 Unsuitable ••• 0.1 

The quality of the water at Locate represents the quality of the water that is ~eaving the Powder River drainage basin. Except 

at low flows, the river water would be suitable for irrigation. During extremely high 

discharges, as represented by the flow of 

11,100 cfs on March 7, 1949, the river water 

would be improved in quality, and the over- all effect on reservoir storage for irrigation use would be beneficial. The classification of 

the river water at Locate is also seen in fig- ure 43. 

Boron concentrations are low; the highest 

concentration that was reported was· 0.30 ppm. 

Middle Fork Powder River near Kaycee, Wyo. 

Twenty-five samples of water were collected 

for analyses from the Middle Fork at discharges that ranged from 0.2 to 730 cfs. ~11 

samples had a 3 rating (permissible) or be~ter 

as follows: 

Quality of water for irrigation, Middle Fork 

Powder River near Kaycee 

Number Irrigation quality Range in daily 

of mean discharge 

samples Rating Grade (cfs) 

7 2 Good· •.••.•••• 98 to 730 

18 3 Permissible •• 0.2 to 356 

The following table shows that the quality 

of the water in the Middle Fork n.ear Kaycee 

is satisfactory even during extremely low 

flows: 

Quality of water for irrigation, Middle Fork 

Powder River near Kaycee 

Electrical 

Discharge Percent conductivity Grade (cfs) sodium (micromhos per em at 25 C) 

0.2 44 1,630 Permissible. 

1.7 42 1,830 Do. 

2.5 35 1,570 Do. 

16 35 1,250 Do. 

The uniform quality of the river water is 

partly explained by the fact that the Middle 

Fork rises in an area underlain by pre-Cambri- an granites, and all its major tributaries, 

except Buffalo Creek, have the characteristics 

of mountain streams. Most of the salt content 

in the river water near Kaycee is probably derived from Buffalo Creek, minor tributaries, 

(see fig. 44) and from return irrigation flows. 

Figure 43 shows the graphical classification 

of water in the Middle Fork • 

Figure 44.--Minor tributary of the Middle Fork Powder River above Kaycee. 

Encrustration of salts along stream channels occurs frequently along 

minor tributaries in this area. 
Of nine samples that were analyzed for boron, eight had concentrations of less than 

0.35 ppm; thus boron does not present a problem. 

Crazy Woman Creek near Arvada, Wyo. 

Five samples of this creek water were ana- lyzed, and four were rated as "permissible" 

and one as "doubtful." The percentage of so- dium of 25 to 30 was uniform, whereas the salt 

concentration (as micromhos per em at 25 C) 

showed considerably greater variation. The 

highest concentration of boron that was re- ported (based on four samples) was 0.40 ppm 

and is not considered to be critical. 

Clear Creek near Buffalo, Wyo. 

The water in Clear Creek near Buffalo rated 

2 (good) on the basis of four samples that were collected at discharges from 2.3 to 332 

cfs. The water at this station was better in 

quality than that at other scheduled sampling 

points in the basin as is apparent from exam- ination of figure 43. Boron is not present in 

harmful concentrations. 

Clear Creek near Arvada, Wyo. 

At the mouth of Clear Creek, approximately 

80 miles downstream from Buffalo, the creek 

water is considerably more mineralized, but 

the quality of the water is nevertheless rated as 3 (permissible) or better. Of five samples, 

two are graded as "good" and three as "permissible"; the latter samples represent waters at 

low discharge. The quality of the water at the 

mouth is influenced by return irrigation flows 

that enter Clear Creek in the reach between 

the Buffalo and the Arvada stations. Boron is 

not present in significant amounts. 

Chemical Quality and Domestic Use 

Any water supply for domestic use should be 

clear,·pleasant to the taste, of reasonable 

temperature, neither corrosive nor scale 

forming, free fromminerals that would produce 

undesirable physiological effects, and free 

from arganisms that are capable of producing 

intestinal infections. To accomplish this 

ideal, departments of health have from time to 

time established standards that govern the 

quality of water under their jurisdiction. The 

only Nation-wide government standards pertaining to the quality of potable water supplies are the Drinking Water Standards of the U. S. 

Public Health Service (1946). These standards were first enacted in 1914 under the provisions of the Interstate Quarantine Regulations 

and have since been revised in 1925, 1942, and 

1946. Specifically, these standards apply on- ly to the waters that are used for drinking 

and culinary purposes on railroad cars, aircraft, and vessels in interstate traffic. However, the standards are generally accepted by 

most States for evaluating municipal supplies, 

and those standards that pertain to chemical 

constituents ar~reproduced in part in the 

following table: 

Standards regarding chemical constituents 

Limits (ppm) 

Copper....................... 3. 0 

Zinc......................... 15 

Iron plus manganese.......... .3 

Magn·esium ••.••..••••••••• :... 125 

Chloride..................... 250 

Sulfate. • • • • • • • • • • • • • • • • • • • • • 250 

Fluoride. . • . • • . • • • • • • • • • • • • • • 1. 5 

Phenolic compounds as phenol. .001 

67 

Total solids................. 500 (1,000 

permitted) 

Most of the surface waters in the Powder 

River drainage basin, with the exception of 

the mountain streams, would not meet the suggested limits as to sulfate and dissolved solids. The dissolved solids often exceed 1,000 

ppm, and sulfate may constitute more than 50 

percent of these solids. However, it is noted 

that waters containing more than 1,000 ppm of 

dissolved solids have been used for years in 

many western regions of the United States 

without adverse effects. The limits as to 

iron (including manganese), magnesium, chloride, and fluoride would not in general be ex- ceeded. The tributary waters, as a rule, are of better domestic quality than the main stem 

waters. 

Rural residents who are accustomed to drir~king mineralized waters often find less saline 

waters unpalatable. The effects of a change 

in water are often related to the physiological action of the mineral constituents (Ameri- can Water Works Association, 1950). When the 

mineral character of a drinking water supply 

differs appreciably from one previously used, 

this difference may affect the mineral balance 

of the human body. 

SUMMARY OF RESULTS 

Rocks in the drainage basin range in age 

from pre-Cambrian to Recent. The pre-Cambrian 

and Paleozoic rocks crop out in the mountains 

and are resistant to erosion. Areas outside 

the mountains are underlain by Mesozoic and 

Tertiary rocks. Mesozoic rocks underlie the 

plains south and west of Sussex and a smaller area north and east of the Little Powder River. 

Both the Mesozoic and the Tertiary rocks erode 

readily. 

The Powder River, the South Fork Powder 

River, and Salt Creek are sediment-laden 

streams that flow on slopes of 10 ft or less 

per mile. In the mountains the streams, including the headwaters of the Middle Fork 

Powder River and Crazy Woman and Clear Creeks, are clear and fall more than 100 ft per mile over most of their lengths. 

The processes of erosion and deposition are shown by a gully that is an ephemeral tributary of Salt Creek near its mouth. A change 

in local base level is suggested as a probable cause of gully formation. 

Average artnual runoff in the Powder River 

drainage basin ranges from a fraction of an inch over much of the plains area to more tha~ 

15 in. near the crest of the Bighorn Mountains. 

It averages less than 1 in. over the entire 

basin. Much of the runoff in the mountains is 

from snow melt. In the plains region, runoff 

is caused mostly by summer storms. The trend 
68 

of discharge of the Powder River at Arvada 

and of Clear Creek near Buffalo has been 

downward during the period of stream-flow rec- ords. About 70,000 acres of land are irrigated by diversions from streams in the Powder River 

drainage basin. 

The record.s of suspended-sediment discharge show an average or about 5,500,000 tons an- nually for the Powder River at Arvada during a period of nearly 5 yr that ended September 30, 1950. The average annual water discharge during the period was about 200,000 acre-ft. 

The average concentration weighted with water 

discharge was 2 percent. 

Nearly all the records of suspended sediment 

at the seven other stations were for only a few months of 1950, but some records were obtained during 1949 on the Middle Fork Powder 

River above Kaycee. Because the average stream 

flow during 1950 was close to the minimum an- nual flow for many years of record, the sediment records during 1950 probably are considerably below the average rate of suspended- sediment discharge. Concentrations and tonnages of suspended sediment were very low near the mouths of Clear and Crazy Woman Creeks. 

Weighted average concentrations for the Middle 

Pork Powder River were less than 0.2 percent 

at the station above Kaycee and were about 0.4 

percent at the station near Kaycee. From May 17 to September 30, 1950, the average weighted concentration for the South Fork Powder River near Kaycee was about 1.4 percent, which is 

undoubtedly far below the average concentration to be expected at this station. From 

March 1 to September 30, 1950, the suspended- sediment discharge of the Powder River was ap~ 

proximately 1,500,000 tons at Sussex, 

2,600,000 tons at Arvada, and·4,300,000 tons near Locate. 

The sediment carried in suspension by the 

Powder River is composed of fine particles. 

For each sampling station the unweighted aver- age of all particle-size distributions of sam- ples that were analyzed in a dispersion medium 

showed that at least 80 percent of the parti- cles were finer than 0.062 mm and that the me- dium sizes were less than 0.009 mm. Particle 

sizes were smaller for the South Fork Powder 

River near Kaycee than for any of the other 

sediment stations and averaged 97 percent smaller than 0.062 mm. 

Particle sizes of the suspended sediment of 

the Powder River at Arvada indicate a specific weight or 56 lb per cu rt for a deposit that 

might form in a reservoir without being com- pacted over long periods of time or under the 

weight of appreciable quantities of overlying deposits. At this specific weight, the sus- pended sediment discharged at the Arvada station from April 4, 1946, to September 30, 

1950, would occupy a computed volume of 

21,420.·acre-ft. 

Although quantities of sediment discharged as bed load by the Powder River at Arvada can- not be computed accurately, the computations indi~ate that bed-load discharge is only about 

2 percent of the discharge of suspended sediment. Certainly the percentage of the total 

sediment discharge that is transported as bed 

load at Arvada is very small. Additional observations and computations are planned to obtain a more dependable estimate of the rate 

of discharge of bed-load sediment at Arvada. 

Nearly all the sediment transported by the 

Powder River and its tributaries comes from 

the plains area, which is underlain by Mesozoic and Tertiary rocks. Much of it comes from gullies that_ are actively eroding and 

from erosion of alluvial deposits along the 

main streams. Studies are being continued by the Geological Survey to delineate more ex- actly the sources of sediment in the Powder 

River basin. 

The variation in the chemical quality of wa- ters in the Powder River drainage basin is 

largely the result of geological influences. 

Streams traversing areas of granitic rocks 

contain waters of low mineral content, where- as streams flowing through regions underlain 

by shale carry high concentrations of soluble 

salts. The chemical quality of the water in 

the Powder River and its tributaries is affected also by water discharge, ·the higher concentrations of salts as a rule correspond- ing with periods of low water discharge •• 

As an irrigation supply, the main-stem wa- ter at Arva6a would be rated as "permissible" for all but very low flows. Most tributaries 

to the Powder River except Crazy Woman Creek 

furnish water that would be rated from •per- missible" to "good." The main-stem waters are objectionable for general domestic use because 

ot high concentratio~s of dissolved solids, 

but the tributary waters in most instances are of better quality. 

RBFBRBNCBS 

Am. Water Works Assoc., 1950, Water quality and treatment, 2d ed., 451 PP• 

Boyer, M. c., and Laursen, B. M., 1950, Stabilization and improvement of rivers, J.D.. 

Rouse, Hunter, and others, Engineering hy- draulics, pp. 815-817, New York, John Wiley and Sons, Inc. 

Brown, R. w., 1949, Paleocene of the Rocky Mountains and plains: U. s. Geol. Survey Prelim. Map. 

Bur. of the Census, 1942, Irrigation·or agri- cultural lands: u. s. Bur. of the Census, 

16th Census, 1940. 

Cham. and Bng. News, 1951, Water for irrigation use: vol. 29, no. 11, PP• 990-993. 

Clarke, F. w., 1924, The data of geochemistry, 5th ad.: u. s. Gaol. Survey Bull. 770. 

Colby, B. R., and Oltman, R. B., 1948, Discharge and runoff in the Missouri River basin: u. s. Gaol. Survey Circ. 37. 

Congressional documents, 1934: 73d Cong., 2d 

sass., H. Doc. 256. 

Corbett, D. M., and others, 1943, Streamgaging procedure: u. s. Gaol. Survey WaterSupply Paper 888. 

Darton, N. H., 1906, Geology of the Bighorn Mountains: u. s. Gaol. Survey Prot. Paper 

51. 

Du Boys, P., 1879, Le Rhone at las rivieres a lit affouillable: Annales de ponts et chau• 

sees, 5 ser., tome 18, vol. 2, pp. 149-195. 
Dunnewald, T. J., and others, Soil survey of 

Johnson County, Wyoming: U. s. Bur. Chemistry and Soils, ser. 1933, rept. 28. 

Einstein, H. A., 1950, The bed-load function 

for sediment transportation in open channel· 

flows: U. S. Dept. Agr. Tech. Bull. 1026. 

Follansbee, Robert, 1923, Surface waters of 

Wyoming and their utilization: U. S. Geol. . Survey Water-Supply Paper 469. 

Gilbert, G. K., 1914, Transportation of debris 

by running water: U. S. Geol. Survey Prof. 

Paper 86. 

Harbeck, G. B., Jr., 1948, Reservoirs in the 

United States: U. S. Geol. Survey Circ. 23. 

Hares, C. J., and others, 1946, Geologic map of the southeastern part of the Wind River 

Basin and adjacent areas in central Wyoming: 

u. s. Geol. Survey Oil and Gas Inv., Prelim. 

Map 51. 

Israelsen, O. w., 1950, Irrigation principles 

and practices, 2d ec., 405 pp., New York, 

John Wiley and Sons, Inc. 

Lane, B. w., and others, 1947, Report of the 

subcommittee on sediment terminology: Am. 

Geophys. Union Trans., vol. 28, no. 6, 

PP• 936-938. 

Lane, E. W., and Koelzer, v. A., 1943, Density of sediments deposited in reservoirs: u. S. Army, Corps of Eng., St. Paul, Minn., 

Rept. no. 9 of a study of the methods used 

in measurement and analysis of sed!ment 

loads in streams, 60 pp. 

Love, J. D., and othe~s, 1945, Stratigraphic sections and thickness maps of Jurassic 

rocks in central Wyoming: u. s. Geol. Survey Oil and Gas Inv., Prelim. Chart 14. 

Love, J. D., and Weitz, J. L., 1951, Geologic 

map of the Powder River Basin and adjacent 

areas, Wyoming: U. S. C.eol. Survey Oil and 

Gas Inv., Map OM 122. 

Raisz, Erwin, 1939, Map of the landforms of 

the United States, Inst. Geog. Expl., 

Harvard Univ., Cambridge, Mass. 

69 

Reeside, J. B., Jr., 1944, Maps sh~wing thick- ness and general character of the Cretaceous 

deposits in the western interior of the 

United States: U. S. Geol. Survey Oil and 

Gas Inv., Prelim. Map 10. 

Scofield, C. S., 1936, The salinity of irriga- tion water: Smithsonian Inst. Ann. Rept., 

1935, PP• 275-287 • 

Shulits, Samuel, 1935, The Schoklitsch bedload formula: Engineering, vol.,l39, 

PP• 644-646, 687. 

Thomas, H. D., 1948, Summary of Paleozoic 

stratigraphy of the Wind River Basin: 

Wyoming Geol. Assoc., 3d Ann. Field Cont. 

Guide Book, pp. 79-95. 

Thompson, R. M., and others, 1949, Stratigraphic sections of pre-Cody Upper Creta- ceous rocks in central Wyoming: U. s. Geol. 

Survey Oil and Gas Inv., Pre~lm. Chart 36. 

Thorp, James, and others, 1939, Soil survey of Sheridan County, Wyoming: U. s. Bur. 

Chemistry and Soils, ser. 1932, rept. 33. 

Twenhofel, w. H., and Tyler, s. A., 1941, 

Methods of study of sediments, 183 pp., 

New York, McGraw-Hill Book Co., Inc. 

u. s. Army, Corps of Eng., 1946, Review re- port on flood control and other purposes, Yellowstone River and tributaries, supplement VI, Silt studies. 

U. S. Public Health Service, 1946, Drinking 

water standards: Public Health Repts., 

vol. 61~ no. 11, pp. 371-384. 

Wegemann, c. H., 1918, The Salt Creek oil 

field, Wyoming: U. S. Geol. Survey Bull. 

670. 

Wilcox, L. v., 1948, The quality of water for 

irrigation use: U. s. Dept. Agr. Tech. 

Bull. 962. 

BASE DATA 

(Tables 14-34) 

71 
72 

Table 14.-~onthly and annual summary o£ water and suspended-sediment discharge, South Fork Powder River near Kaycee, W)'o. 

Suspended sediment 

Water Daily load Concentration 

Month discharge Runot£ Load (tons) (ppn) (second- (acre-feet) (tons) Weighted Maximum toot-days) Mean ~aximum Hi~imum mean daily 

1950 

May 17-31 •••••••••••• 660 1,310 6,980 46$ 3,480 46 .3,920 13,400 

June •••••• ~ •••••••••• .397.9 789 1,060 35 2.32 t 987 7,520 

July ••••••••••••••••• 442.6 878 .34,590 1,120 12,000 t 28,900 65,100 

August ••••••••••••••• 152.4 .302 56 1.8 21 t 136 645 

September •••••• : ••••• 416.8 827 .3.3,950 1,130 25,100 t 30,200 6.3,300 

May 17 to Sept. JO ••• 2,069. 7 4,110 76,640 559 25,100 t 13,700 65,100 

t Sediment discharge less than 1 ton. 

Table 15.-~onthly and annual summary or water and suspended-sediment discharge, Powder River at Sussex, wyo. 

Water 

Month discharge Runo££ 

{second- (acre-feet) 

toot-days) 

1950 

March ••••••••••••• 4,642 9,210 

April ••••••••••••• 10,355 20,540 

Kay ••••••••••••••• 26,366 52,340 

June •••••••••••••• 5,989 11,880 

July •••••••••••••• 1,536 3,050 

August •••••••••••• 284.8 565 

September ••••••••• 1,104.7 2,190 

Mar. 1 to Sept. 30 50,297.5 99,780 

a Includes estimated loads tor a few days. 

t Sediment discharge less than 1 ton. 

Load 

(tons) 

a 60,420 

165,600 

1,139,000 

40,570 

56,610 

260 

17,780 

1,500,000 

Suspended sediment 

Daily load Concentration 

(tons) (ppn) 

Weighted Maximum Mean Maximum Minimum mean daily 

1,950 4,450 . ........ 4,620 8,670 

6,190 25,400 1,410 6,640 17,700 

3'b, 700 96,600 1,810 16,000 40,200 

1,350 12,700 12 2,510 16,200 

1,830 16,500 9 13,700 44,200 8.4 147 t 336 2,180 

593 9,.320 t $,960 44,400 

7,010 96,600 t 11,000 44,400 

Table 16.--Honthly a..-1d annual su.mmary or water and suspended-sediment discharge, Powder River at Arvada, Wyo. 

Suspended sediment 

Water Daily load Concentration 

Month discharge Runoff Load (tons) (ppn) (second- (acre-teet) (tons) Weighted Maximum toot-days) Mean Maximum Minimum mea.'l daily 

1946 

Apr. 4-30 ••••••••• 11,552 22,910 466,100 17,300 54,800 3,660 14,900 36,300 

May ••••••••••••••• 14,776 29,31a 411,000 13,)00 19,000 7,690 10,300 14,600 

June •••••••••••••• 18,287 .36, 270 1,531,000 51,000 533,000 2,840 31,000 78,000 July •••••••••••••• 11,268 22,.350 1,008,000 . 32,500 374,000 88 )3,100 58,600 

August •••••••••••• 141 280 131 4 74 0 344 546 

September ••••••••• 4,757 9,440 357,700 11,900 70,400 0 27,800 66,000 

Apr. 4 to Sept. 30 60,781 120,600 3,774,000 21,000 533,000 0 23,000 78,000 

October ••••••••••• 4,492 8,910 69,680 2,250 5,560 484 5,740 14,200 

November •••••••••• 4,805 9,530 62,710 2,090 5,910 84 4,8.30 8,3.30 December •••••••••• 3,83.3 7,600 · b JJ,OOO 1,100 .......... . ....... .3,200 . ....... 1947 

January •. •. • •• • • •• • 2, 76.3 $,480 b .3,500 llO .......... . ........ 470 . ....... February •••••••••• 5,163 10,240 b 20,000 710 5,260 ........ 1,400 ........ March ••••••••••••• 29,431 $8,)80 b 796,000 25~ 700 155,000 ........ 10,000 28,000 

April •.•••••••••••• 10,0.38 19,910 327,000 10,900 43,400 3,040 12,100 23,800 

May ••••••••••••••• r 43,5$0 86,.380 2,.320,000 74,800 221,000 1.3,000 19,700- .32,200 

June •••••••••••••• 23,23.3 46,080 1,044,000 .34,800 189,000 9,280 16,600 41,100 July •••••••••••••• 10,468 20,760 6.39,100 20,600 300,000 464 22,600 50,500 

August." •••••••••• 225.9 448 472 15.2 173 0 77.3 1,940 September.-. ••••••• 5$8.) l,UO a 7,240 241 2,.310 0 4,800 18,600 

Water year 1946-47 1.38,560.2 274,ts00 b 5,.32.3,000 14,600 )00,000 0 14,200 so,soo 

See footnotes a~ end of table, p. 7.3. 
73 

Table l6.~onthly and annual summary of water and suspended-sediment discharge, Powder River at Arvada, Wyo.--con. 

Water 

Month d!.scharge Runoff 

(second- (acre-feet) 

toot-days) 

1947-Continued 

October ••••••••••• ' 2,665 5,290 

November •••••••••• 4,314 8,560 

December •••••••••• 3,345 6,630 

1948 

January ••••••••••• 2,541 5,040 

February •••••••••• 6,438 1?, 770 

March ••••••••••••• 26,728 53.010 

April ••••••••••••• 7,498 14,870 

May ••••••••••••••• 16,437 32,600 

June •••••••••••••• 39,287 77,920 

July •••••••••••••• 12,372 24,540 

August •••••••••••• . 2, 286.7 4,540 

September ••••••••• 1,557.8 3,090 

Water year 1947-48 125,469.5 24d,900 

October •••••• : ••••• 4,041 8,020 

November •••••••••• 3,809 7,560 

December •••••••••• 2,633 5,220 

1949 

January ••••••••••• 1,824 3,620 

February •••••••••• 2,165 4,290 

March ••••••••••••• 27,296 54,140 

April ••••••••••••• 9,837 19,510. 

May. • • • • • • • • • • • • • • 17,040 33,800 

J:.1ne •••••••••••••• 19,994 39,660 

July •••••••••••••• 3,922.9 7,780 

August •••••••••••• 4.0 7.9 

September ••••••••• 184.6 366 

Water year 1948-49 92,750.5 184,000 

October ••••••••••• 2,806 5,570 

November •••••••••• 2,680 5,320 

December •••••••••• 713 1,410 

1950 

January ••••••••••• 908 1,800 

February· •••••••••• l, 770 3,510 

March ••••••••••••• 6,860 13,610 

April ••••••••••••• 11,335 22,480 

May ••••••••••••••• 27,164 53,880 

June •••••••••••••• 9,806 19,450 

July •••••••••••••• 1,967.5 3,900 

August •••••••••••• 249.2 494 

September ••••••••• 141 280 

Water year 1949-50 66,399.7 131,700 

a Includes estimated loads tor a few days. 

b Includes estimated loads tor many days. 

Load 

(tons) 

26,920 

26,110 

b 7' 700 

a 3,550 a 22,930 

1,027,000 

116,300 

922,900 

5,81)8,000 

979,700 

162,500 

274,700 

a 9,428,000 

303,900 

31,240 

4,070 

a 1,720 

3,730 

640,500 

2<>3,800 

903,300 

2,303,000 

479,000 

110 

8,690 

a 4,883,000 

78,400 

42,260 

b 1,600 

a 804 

4,380 

91,730 

395,900 

1,833,000 

179,000 

80,570 a 25,360 

4,910 

a 2, 738,000 

Suspended sediment 

Daily load Concentration 

(tons) (ppn) 

Weighted Minimum Maximum Mean Maximum mean daily 

868 3,200 85 3,740 7,000 

870 2,160 11 2,240 5,000 

250 2,560 . ...... 850 4,870 

115 189 . ...... 518 777 

791 5,710 111 1)320 3,300 

33,100 120,000 290 14,200 42,700 

3,880 7,820 1,420 5,740 9,580 

?9,300 146,000 4,570 20,8QP 40,000 

195,000 1,200,000 5,670 55,200 8l,Qoo 

31,600 305,000 125 29,300 50,000 

5,240 61,000 1 26,300 51,500 

9,160 185,000 0 65,300 87.,000 

25,800 1,200,000 0 27,800 87,000 

9,800 183,000 129 27,900 63,400 

1,040 2,620 142 3,040 7,200 

131 336 68 572 920 

56 147 18 349 718 

133 1,830 33 638 2,050 

20,700 65,000 723 8,690 25,600 

6,790 11,100 3,690 7,670 9,410 

29,100 95,500 8,960 19,600 31,300 

76,800 382,000 1,000 42,700 67,000 

15,500 2h9,000 0 45,200 70,500 

3.5 104 0 10,200 10,700 

290 3,270 0 17,400 97,200 

13,400 382,000 0 19,500 97,200 

2,530 9,000 10 10,300 22,500 

1,410 2,880 350 5,840 7,220 

52 464 . ...... 831 4,910 

26 49 8 328 497 

156 540 38 917 2,220 

2,960 11,800 150 4,950 13,200 

13,200 28,200 7,770 12,900 21,700 

59,100 lh3,000 6,440 25,000 46,700 

5,970 13,800 202 6,760 12,800 

2,600 50,400 7 15,200 34,000 

818 16,000 0 36,300 45,000 

164 1,730 0 12,900 30,600 

7,500 143,000 0 15,300 46,700 

Table 17.-~onthly and annual summary of water and suspended-sediment discharge, Powder River near Locate, Mont. 

Water Suspended sediment 

Month discharge Runoff Load Daily load (tons) Concentration (ppm) 

(second- (acre-teet) (tons) Maximum Minimum Weighted Maxim'4Jil 

toot-days) Mean mean daily 

1950 

March ••••••••••••• 2,485 4,930 a 15,360 495 4,:p.o ....... 2,290 7,610 

April .••••••••••••• 37,077 73,540 1,0.138,000 36,300 126,000 11,100 10,900 21,200 

May ••••••••••••••• 44,862 88,980 2,423,000 78,200 218,000 19,900 20,000 35,600 

June •••••••••••••• 31,478 62,440 637,800 21,300 54,100 6,670 7,500 14,100 

July •••••••••••••• 9,316 18,480 60,860 1,950 22,$00 86 2,410 12,900 August •••••••••••• 2,946 5,840 83,970 2,710 1!:),400 4 10,600 20,200 September ••••••••• 837.2 1,660 842 28 155 t 372 585 

Mar. 1 to Sept. 30 129,001.2 255,900 a 1~,310,000 20,100 2:!.8,000 t 12,400 35,600 

a Includes estimated loads for a few days. tJSediment discharge less than 1 ton. 
74 

Tab1~ 18.-~onth1y and annual summary of water and suspended-sediment discharge, Middle Fork Powder River above 

·Kaycee, Wyo • 

Water 

Month discharge Runoff 

(second- (acre-feet) 

foot-days) 

1949 

Apr. 22-30 ••••••••• 1,379 2,740 

May •••••••••.•••••. 5,921 11,740 

June ••••••••••••••• 3,292 6,530 

.July •••••••.••••••• 1,198 2,380 

August ••••••••••••• 982 1,950 

September •••••••••• 1,230 2,440 

Apr. 22 to Sept. 30 14,002 27,780 

October •••••••••••• 1,508 2,990 

November ••••••••••• 1,384 2,750 

December ••••••••.•• 1,075 2,130 

1950 

January •••••••••••. 1,066 2,110 

February ••••••••••• 1,195 2,370 

March •••••••••••••• 1,519 3,010 

April •••••••••••••• 2,713 .5,380 

May •••••••••••••••• 7,966 15,880 

June ••••••••••••••• 3,241 6,430 

July ••••••••••••••• 1,227 2,430 

August ••••••••••••• 961 1,910 

September •••••••.•• 1,1-56 2,290 

Water year 1949-50. 25,011 49,680 

a Includes estimated loads for a few days. 

b Includes estimated loads for many days. 

t Sediment discharge less than 1 ton. 

Load 

(tons) 

9,560 

19,680 

40,140 

267 

a 733 a 224 

a 70,600 

a 167 a 136 

b 270 

b 310 

a 730 a. 1,050 

a 14,840 

a 86,960 

7!38 

155 a 3,190 

a 189 

a 108,800 

Suspended sediment 

Daily load (tons) Concentration {ppm) 

Weighted Maximum Mean I"iaximum Minimum mea::1 daily 

1,060 2,830 89 2,570 3,690 

630 2,890 82 1,230 5,030 

1,340 18,700 10 4,520 21!,000 

8.6 69 1 82 474 

24 446 -~ 276 1,390 

7.5 24 2 67 214 

436 18,700 l 1,870 24,000 

5.4 10 3 41 . ....... 4.5 11 1 36 . ....... 8.7 . . . . . . . . . ......... 93 . ....... 10 ......... ......... 108 ········ 26 ········· ......... 226 ........ 34 ......... . ........ 256 . ....... 495 2,800 10 2,030 ........ 2,810 15,100 an 4,040 8,710 

26 109 4 90 215 

5.0 22 1 h7 168 

103 2,25:::> t 1,230 ........ 6.3 22 1 61 ........ 298 15,100 t 1,610 8,710 

Table 19 .-~onthly and annual sU1Tllll.iiry of water and suspended-sediment discharge, Middle Fork Powder River near Kaycee, Wyo. 

Water 

Month discharge Runoff (s~cond- (acre-feet)' 

foot-days) 

1950 

March ••••••••••••• 3,632 7,200 

April ••••••••••••• 6,589 13,070 

May ••••••••••••••• 16,139 32,010 

June •••••••••••••• 5,744 11,390 

July ••••.••••••••• 363.9 722 

August •••••••••••• 74.9 lh9 

Sapteruber ••••••••• 1,040.8 2,:::>60 

Mar. 1 to Sept. 30 33,583.6 66,600 

a Includes estimated loads for a few days. 

b Includes estimated loads for many days. 

t Sediment discharge less than 1 ton. 

Load 

(tons) 

a 5,200 a 52,500 a 296,000 

b 8,500 

a 717 a 190 

a 297 

a 363,400 

Suspended sediment 

Daily load (tons) Concentration (ppm) 

Weighted Maximum Mean MaxL'Tlum Minimum mean daily 

168 ......... ......... 530 ........ 1,750 ......... 44 2,950 ......... 9,550 39,100 ......... 6,790 . ....... 283 1,150 .......... 548 1,150 

23 ......... t 730 . ....... 61 172 t 940 1',910 

9.9 58 t 106 375 

1,700 39,100 t 4,010 ........ 

Table 20.~onthly and annual summary of water and suspended-sediment discharge, Crazy Woman Creek near Arvada, Wyo. 

Water Suspended sediment 

Month discharge Runoff Daily load (tons) Concentration (ppm) 

(second- (acre-feet) Load Weighted Maximum 

foot-days) (tons) Mean MaJCimum Min~um mean daily 

19.50 

Mar. 15-31 •••••••• 516 1,020 204 12 36 2 146 270 

April ••••••••••••• 2,535 5,030 14,050 468 3,640 2h 2,050 7,170 May ••••••••••••••• 5,232 10,380 66,260 2,140 11,100 15 4,690 11,100 June •••••••••••••• 4,069 8,070 11,470 382 1,570 19 1,040 2,460 J"uly.~····· ••••••• 935.4 1,860 357 12 55 t 141 308 August •••••••••••• 162.0 321 14,910 481 12,500 0 34,100 36,500 September ••••••••• 162.7 323 a 29 1.0 4 0 66 ........ Mar. 15 to Sept.30 13,612.1 27,000 a 107,300 536 12,500 0 2,920 36,500 

a Includes estimated loads for a few days. t Sediment discharge less than 1 ton. 
75 

Table 21.-Month]¥ and annual SUJIIIDarT ot water and suspended.-secliment diBcharge, Clear Creek near Arvada, Wyo. 

Water Suspended sediment 

. discharge Runoff D~ load (tons) Concentration (ppm) Month (second- (acre-teet-) Load 

toot-d.qs) (t-ons) Mean Max:l.tm1m Minimum Weighted Ma:x:l.DIDn mean c1ail7 

1950 

Ma:r. 21-31 ••••••••••• 1,.563 3,100 a 350 32 ......... . ........ 83 . ....... April•••••••••••••••• 5,461 10,8:30 3,120 104 1,320 4 212 1,380 

~·················· 10,220 20,270 14,510 46S 2,490 4 526 1,1.30 

June••••••••••••••••• 17,312 34,340 32,440 l,OSO 7,660 4 694 2,200 

July ••••••••••••••••• 3,517.2 6,980 " a 964 31 402 t 100 1,230 Ausust ••••••••••••••• 504·5 1,000 679 22 536 t 49S 980 

September •••••••••••• 2,576.2 ;,no 603 20 68 t S7 141 

Mar. 21 to Sept. 30 •• 41,153·9 SJ..,630 a 52,670 271 7,660 t 474 2,200 

a Includes estimated loads tor a few dqs. t Sediment load less than 1 ton. 

Table 22.-Particle-size ana:cyses ot suspended sediment, South Fork Power River near Kqcee, Wyo. 

Diet~ ot analyses: s, sieve· P, pipette• N, in native waters· W, in distilled water; C, chemica.l:cy' dispersed• ' ' B, botb withdrawal. 'b:J.bi/ , M, mechanical.J¥ dispersed; 

Suspended sediment 

Water Cone en- Concen- Methods 

Date Time dis- tration tration of Percent finer t~ indicated size (liD) ot charge ot suspension analysis (cts) sample a.na.lyzed 

(ppm) (ppa) 0.002 0.004 o.oos o.o16 0.031 o.o62 0.125 0.250 

1950 

Jfq ) ••• 12:54'p.m. a 336 69,900 58,100 ..... 0 71 74 S6 91 9S 100 SPN 

Do •••• 12:54 p.m. a 336 69,900 5,010 35 ItS 57 70 S1 93 98 100 SN1H 

Mq' u •• 1:33 p.m. a 450 ;o,5oo 39,700 ..... 0 5 61 76 sa 97 100 SPN 

Do •••• 1:33 p.m. a450 50,500 5,500 29 36 IP 55 66 S4 94 99 BWC 

Mq' 17 .. 10:00 a.m. a 96 14,000 4,590 ..... 64 ..... 8:3 ..... S9 95 97 SPiO( 

- ~ 2; •• 5:45p.m. a 57 2,570 2,100 ..... 76 ..... 90 ..... 96 ..... . .... SNJH 

June 2 •• 9:45 a.m. a 29 1,210 916 ..... 6; ..... S7 ..... 91 . .... . .... SN1H 

June a •• 10:45 a.m. 20 3,360 2,720 ..... 67 ..... 91 ..... 9S . .... ..... SPWCH 

June 21. 5:15 p.m. 12 10,900 9,080 ..... S7 ..... 98 ..... 100 ..... ..... SPWCH 

~4-· 5:45p.m. llS 8:3,500 81 920 ..... 63 ..... 93 ..... 98 ..... . .... SN:M 

~ 5·· 8:45 a.m. 66 68,300 7,460 ..... 72 . .... ..... ..... 99 . .... ..... SPWCM 

~6 •• 6:40 p.m. 16 21,200 24,200 12 13 14 97 99 100 ..... ..... SPH 

Do •••• 6:40p.m. 16 21,200 3,440 ..... S6 95 9S 99 100 ..... . .... BWC 

~12. S:OO a.m. 38 62,300 6,510 ..... 71 . .... 9S ..... 99 ..... ..... SPWCM 

~13· 10:50 a.m. 8.3 1,200 890 ..... 7S ..... sa ..... 99 . .... ..... SPWCH 

~2;. 7:45 a.m. 16 6,100 4,980 ..... sa ..... 97 ..... 99 . .... ..... SPWCM 

~26. 5:30p.m. 75 55,500 5,820 ..... 6o ..... sa ..... 99 ..... . .... SPWCM 

~ 27. 3:44p.m. ·12 10,900 11,000 ..... 0 4 93 99 99 ..... . .... SPN 

Do •••• 3:44p.m. 12 10,900 5,26o 6S sa 94 97 99 100 ..... ..... SPWCM 

Sept. ll 1:45 p.m. 15 3,240 2,470 ..... 84 ..... 93 ..... 99 . .... . .... SPWCK 

Do •••• 6:10 p.m~ 16 1,950 1,400 . .... 93 ..... ..... ..... 99 . .... . .... SPWCH 

Sept. 15 S:OO a.m. 15 1,300 1,070 ..... 69 . .... 83 . .... 98 ..... . .... SPWCH 

Do •••• 5:00p.m. 17 15,000 6,o6o ..... 69 . .... 92 .. .. . 99 . .... . .... SPWCM 

Sept. 20 8:30a.m. 22 5,500 4,300 ..... 6S ..... a; ..... 96 . .... . .... SPWCH 

Sept. 21 a:30 a.m. 152 62,600 6,000 ..... 63 ..... 90 . .... 98 ..... . .... SPWCM 

Sept. 24 8:30 a.m. 14 5~500 4,420 ..... 97 ..... ..... ..... 100 . .... . .... SPWCM 

Sept. 25 4:(11 p.m. 9.6 1,720 2,010 ..... 0 2 93 96 100 ..... . .... SPN 

Do •••• 4:(11 p.m. 9.6 1,720 2,130 7S 90 93 93 95 99 ..... . .... SPWCM 

Sept. 30 5:00p.m. 19 2,450 1,750 ..... 75 ..... 93 ..... 97 . .... ..... SPWCH 

a· Hean ~ discharge. 
,Aiethod.s of anaJ.Tses: 

Date T:Lme 

1950 

Mar. 4-•••••• 7:30a.m. 

Mar. 16 •••••• 2:45 p.m. Apr. 6 ••••••• 9:30 a.m. Apr. 7••••••• 6:00 p.m. Apr. 8 ••••••• 5:30p.m. 

Apr. 10 •••••• 9:30 a.m. Apr. 16 •••••• 8:50a.m. ~ 1 •••••••• 9:30 a.m. 

~ 3········ 6:30p.m. 

Mq" 6 •••••••• l:o6 p.m. 

Do ••••••••• l:o6 p.m. 

Ma;y u ..•.... 4:57p.m. 

Ma;y 17······· 6:4l p.m. 

Do ••••••••• 6:4l p.m. 

Ma;r 24······· 2:o6 p.m. 

J\Ule 2 ••••••• 7:20 p.m. 

June 9••••••• 7:00p.m. 

June 14······ 12&00 m. 

June 19······ 10:45 a.m. ~ 2 ••••••• 7:00p.m. 

~ 6 ••••••• 2:49 p.m. ~ 12 •••••• 9:00 a.m. Do ••••••• · •• 9:00 a.m. Jul¥ ]3 •••••• 1:52 p.m. Do ••••••••• 1:52 p.m. 

~ 14······ 9&30 a.m. Jul¥ 27······ 1:13 p.m. Do ••••••••• 1:13 p.m. J~ 28 •••••• 9:30a.m. 

Aug. 13······ 8:05 a.m. Sept. ]J ••••• 1145 p.m. 

Sept. 16 ••••• 3t30 p.m. 

Sept. 21 ••••• 12:30 p.m. 

Sept. 22 ••••• 9:45 a.m. 

Sept. 24····· 8:30a.m. 

Sept. 26 ••••• 1:35 p.m. 

Do ••••••••• 1135 p.m. 

a Mean· claiJT discharge. 

Table 2).--Particle-size ana.lTses ot suspencled. secliment~ Powder River at Sussex, lfTo• 

B~ bottom withdrawal ~be; W, _in distilled water; s~ sieve; J:, pipette; c, chemical.l:y dispersed.; M, mechanical.lJ" dispersed.; 

If, in native waterJI 

Suspended. secliment 

Water Cone en- Methoc:le dis- Concen- tration of Percent finer than inclicated size (Dill) ot charge tration of suspension anaJ.Tsis (cts) sample analyzed (ppm) (ppm) 0.002 0.004 o.oos o.ol6 0.0,31 0.062 0.125 0.250 o.soo 

a 140 6~340 1~530 26 34 57 70 so 88 94 100 ....... BW 

175 7~240 1~150 14 l6 26 36 60 78 90 98 ....... BW 

356 8,o6o 3~520 ....... 53 . ...... 72 . ...... 87 95 99 100 SN:;M 

368 19,200 10~800 ....... 60 . ...... 79 . ...... 92 97 100 . ...... SPWCM 

254 9~720 5~290 ....... 53 . ...... 68 . ...... S6 95 99 100 SPWCM 

590 22~200 15~300 ....... 35 . ...... 56 . ...... 81 90 99 100 SPWCM 

470 ]3~800 s,s5o ....... 37 . ...... 56 . ...... 81 92 99 100 SPWCM 

4l6 10~700 6~970 ....... 34 . ...... 51 . ...... 78, 95 100 . ...... SPWCM 

645 48,500 9~400 ....... 45 . ...... 7l . ...... 89 94 99 100 SPWCM 662 29,900 43,600 ....... 4 19 63 82 91 99 100 . ...... BN 

662 29,900 l3~500 22 33 45 60 74 as 94 99 ....... BW 

1,090 32~500 10,900 ....... 42 . ...... 63 . ...... 91 98 100 . ...... SPWCM 

b 1,450 19~400 20~000 ....... 1 3 31 55 78 96 100 . ...... BN 

b 1,450 19,400 15,100 11 16 22 30 47 76 93 100 ....... BW a 1,01.0 9,510 4,260 ....... 14 . ...... 23 . ...... 60 92 100 . ...... SPWCM 

416 2,420 1,370 ....... 12 ....•.. 19 . ...... 54 88 100 . ...... SPWCM 

254 1,680 682 ....... ll . ...... 19 . ...... 44 79 99 100 SPWCM 200 1,090 832 12 22 56 86 99 - ....... . ...... . ...... 100 SPWCM a 225 16~000 3,050 ....... 59 . ...... 84 . ...... 93 . ...... . ...... . ...... SPWCM 

]30 18~300 7,590 . ....... 69 . ...... 94 . ...... 100 ....... . ...... - . ...... SPWCM 

84 30~600 6,230 ....... 80 . ...... 98 . ...... 99 . ...... . ...... . ...... SPWCM 

180 81,000 8,880 ....... . ...... . ...... 74 . ...... 99 . ...... . ...... . ...... SPN 

180 81,000 1,970 47 56 7l 88 97 99 100 ....... . ...... BWCM 

a42 38,900 37,100 ....... 1 98 99 . ...... 100 ....... ....... . ...... SPN aq2 38,900 5,650 58 78 94 98 ....... 100 ....... . ....... . ...... SPWCM 

60 7,400 5,660 ....... 78 . ...... 94 . ...... 97 ....... . ...... . ...... SPWCM 

50 9,580 9,130 ....... 1 2 73 98 99 . ...... . ...... . ...... SPN 

50 9,500 3,890 ....... 74 87 96 98 99 100 . ...... . ...... BWCM 

29 27,000 5~250 ....... 84 96 98 . ...... . ...... . ...... . ...... . ...... BWCM 

30 3~280 2,530 ....... 73 . ...... . ...... . ...... 99 . ...... . ...... . ...... SPWCM 

a23 890 2~260 ....... 56 . ...... 77 . ...... 91 . ...... . ...... . ...... SPWCM 

a27 4~250 3~100 ....... 70 . ...... 88 . ...... 97 ....... . ...... . ...... SPWCM 

39 3,890 2~830 ....... 61 . ...... 75 . ...... 94 . ...... . ...... . ...... SPWCM 

73 57,700 4,770 ....... 72 . ...... 89 . ...... 95 . ...... . ...... . ...... SPWCM 

67 6~260 4,020 ....... 82 . ...... 94 . ...... 98 . ...... . ...... . ...... SPWCM 

69 1,670 2,450 ....... . ...... 14 72 78 88 . ...... . ...... . ...... SPN 

69 1,670 2,320 49 56 67 74 82 87 ....... . ...... . ...... SPWCM 

b Discharge measur-.mt. 

...:1 

m 
~hods of anaJ.Tses: 

Date TiJDB 

1946 

June 1 ••••••• 2:.30 p.m. June 21 •••••• 1:.30 p.m. 

1947 

Mar. 18 •••••• 11:.30 a.m. 

Oct • .) ••••••• .3:08 p.m. 

1948 

Mar. 18 •••••• a:l5 p.m. Do ••••••••• 8:20p.m. Do .......... 8:50 p.m. 

Mar. 19······ 5:00 p.m. Do ••••••••• 4:45 p.m. 

Apr. a ••••••• 1:.30 p.m. Do ••••••••• 1:.30 p.m. 

Apr. 14•••••• 2:40 p.m. 

Ha;y 4········ 2:50p.m. 

-- 18 ••••••• 2:25p.m. 

Do ••••••••• 2:25 p.m. 

Do ••••••••• 2:25 p.m. Kt1' 26 ••••••• 4:.30 p.m. 

Do ••••••••• 4:.30 p.m. 

June 4······· 12:.30 p.m. 

Do ••••••••• 12:.30 p.m. 

Jul.1" 14······ 4:20p.m. Do ••••••••• ·4:20p.m. 

Do ••••••••• 4:20p.m. 

July 27······ 7:00 p.m. 

Do ••••••••• 7:00 p.m. 

Aug. 17······ 6:00 p.m. Do ••••••••• 6:00 p.m. Sept. 22 ••••• 6:40 p.m. Do ••••••••• 6:40 p.m. 

Oct. S••••••• 12:.30 p.m. Do ••••••••• 12:.30 p.m. 

1949 

Mar • .) ••••••• 10:00 a.m. 

Mar. 11 •••••• 2:00 p.m. 

Do ••••••••• 2:00 p.m. Mar. 2.3 •••••• 2:50p.m. 

Tabl.e 24.--Particle-size analyses of suspended sediment, Polder River at Arvada, Wyo. 

B, bottom withdrawal tube; N, in native w.ters; w, in. distJ.lled water; c, chemic~ dispersed; s, sieve; P, pipette; 

H, JMCbanic~ dispersEIJilf 

SuspeDd.ed. sediment 

Water Concen- Cone endis- tration of tration of Percent finer than indicated size (1111) 

charge sample suspension (cfs) ana.qzed (ppm) (ppm) 0.002 Oe004 o.oos o.Ol6 0.()31 0.062 0.12; 0.2;0 o.;oo. 

5lt4 12,800 9,890 ....... 4 .31 lt4 51 70 84 9.3 ....... 979 .39~200 7,.370 ....... 6 48 7a 81 88 91 96 ....... .3,.360 a,210 6~170 ....... .3 6 .34 . ...... 56 6.3 84 ....... 45 1,030 .3,7SO ....... 2 7 15 25 46 69 97 . ...... 2,140 13,400 6,080 ....... 5 10 . ...... . ....... 88 97 100 ....... 2,140 13,400 5,790 . ...... .37 Sl 62 70 81 94 99 . ...... 2,140 13,400 7,600. ....... .36 so ;a 6a 75 a4 96 ....... 2,140 20,000 9,260 ....... .3 8 lt4 59 66 eo 96 . ...... 2,140 20,000 5,870 ....... .3.3 lt4 56 68 79 91 100 . ...... 2.37 4,700 ............ ....... 27 112 S6 67 95 95 9a . ...... 2.37 4,700 6~7)0 ....... 2 5 18 59 72 94 9a ....... 202 .3,760 2,770 . ...... 4 12 47 65 77 94 9a . ...... 416 7,460 10,900 ....... 1 .3 9 71 81 94 100 . ...... 458 11,800 9,610 ....... 2 6 .30 6a eo 95 100 . ...... 458 11,800 10,.300 . ...... 18 28 40 60 92 95 100 . ...... 458 11,800 10,200 . ...... 18 27 .39 57 74 90 96 . ...... 1,681;> .37,100 4,550 . ...... 2 7 .3.3 72 84 89 96 . ...... 1,690 .37,100 4,940 ....... 2a 40 5.3 70 84 90 96 . ...... 672 20,;oo 5,000 ....... 4 9 45 . ...... 89 95 9a . ...... 672 20,500 ............ ....... .34 46 ;a 75 90 95 99 . ...... 5,000 84,500 8,660 ....... 2 4 24 ....... 76 86 92 . ...... ;,ooo 84,500 a,760 ....... 26 .39 51 66 7a 88 92 . ...... 5,000 a4,500 a,640 ....... 26 .39 51 66 eo 88 97 . ...... 175 7,9.30 6,140 ....... .3 6 . ...... . ...... 89 96 100 . ...... 175 7,9.30 6,490 . ...... Sl 65 74 80 89 97 100 . ...... .35 2,130 2,400 ...... ,. a 14 . ...... . ...... 9.3 97 99 . ...... .35 2,130 2,440 ....... 64 eo 86 89 92 9a 9a . ...... 616 ao,6oo 18,400 ....... 1 .3 70 . ...... 94 96 99 . ...... 616 eo,6oo 16,900 . ...... 47 66 8.3 89 9.3 96 100 . ...... .35 1,760 2,700 ....... . ...... 10 ....... 94 95 95 9a . ...... .35 1,760 2,8.30 ....... 72 88 92 94 96 96 100 . ...... l,lt30 2,660 1,000 . ...... 14 24 )a 40 48 6.3 86 . ...... ;oo 4,170 1,870 ....... 6 44 S6 6.3 7) 88 100 . ...... soo 4,170 1,6.30 ....... .3.3 112 50 ~ ;a 74 90 98 . ...... 6;6 U,400 1,190 ....... .38 S6 70 86 97" 100 ....... . ...... See footnotes at end of table, P• 79· 

Methods 

of 

anal.ysis 

BN 

BN 

BN 

BN 

BN 

BW 

BW 

BN 

BW 

BW 

BN 

BN 

BN 

BN 

BW 

BWC 

BN 

BW 

BN 

BW 

BN 

BW 

J3iC 

BN 

BW 

BN 

BW 

BN 

BW 

BN 

BW 

BN 

BN 

BW 

BW ....:l 

....:l 
Liiethod.s of analy'ses: 

Date Time 

1949 

Apr. 12 •••••• 2:20 p.m. 

Mq 21 ••••••• 11:30 a.m. June 3••••••• 12:42 p.m. June 10 •••••• 10:30 a.m. J~ 6 ••••••• 1:00 p.m. 

J~ 19 •••••• 1:30 p.m. Sept. 2 •••••• 10:55 a.m. Do ••••••••• 10:55 a.m. Do ••••••••• 5:15 p.m. Sept. 12 ••••• 5:20 p.m. 

Oct. 1••••••• 6:10 p.m. 

Oct. 4••••••• 2:]J p.m. Oct. 18 •••••• 12:50 p.m. 

Do ••••••••• 12:50 p.m. Oct. 31 •••••• 11:20 a.m. 

Do ••••••••• 11:20 a.m. Nov. 2 ••••••• 10:53 a.m. Do ••••••••• 10:53 a.m. Nov. 4••••••• 7:30a.m. 

Nov. 17•••••• 10:22 a.m. 

DO••••••••• 10:22 a.m. Nov. 18 •••••• 7:30a.m. 

1950 

Feb. 4••••••• 2:20 p.m. Feb. 21 •••••• 4:40 p.m. 

Feb. 27•••••• 5:10 p.m. 

Mar. 1 ••••••• 4:45 p.m. 

Mar. ]J •••••• 9:10 a.m. 

Mar. 23······ 4:15 p.m. 

Apr. S••••••• 1:55 p.m. Do ••••••••• 6:05 p.m. Apr. 20 •••••• 2:08 p.m. 

Do ••••••••• 2:08 p.m. 

Apr. 25•••••• 5:09 p.m. 

Do••••••••• 5:09 p.m. 

Hal' 9········ 5:30p.m. Hal' 10 ••••••• 1:47 p.m. ~ 18 ••••••• 5:36 p.m. 

Table 24.--Particle-size analy'ses of suspended sed,iment, Pcn«ler River at Arvada, Wyo.-Continued 

B, bottom withdrawal tube; N, in native waters; w, in distJ.l.l.ed water; c., chemica.lly dispersed; s, sieve; P, pipette; M, mechanica.lly disperseS/ 

. SUspended sediment 

Water Concen- Concen- Percent finer than indicated size (mm) dis- tration ot 

charge tration of 811spension 

(c£s) sample ana:cyzed 0.002 0.004 0.008 o.ol.6 0.0,31 0.062 0.125 0.250 0.500 (ppm) (ppm) 

342 10,100 2,240 ········ 36 42 53 81 86 93 96 ....... 7l/:J 24,200 1,120 ....... qh 60 70 78 88 95 98 ....... 5l2 26,100 1,230 ....... 44 72 76 84 92 98 98 ....... 1,350 47,000 1,420 ....... 36 60 66 76 90 95 100 . ...... 264 19,600 1,990 ....... 38 51 68 79 88 93 96 . ...... 44 25,800 2,460 ....... 75 90 96 97 98 98 100 •••••e• 9.8 94,200 3,840 ....... 4 6 96 100 . ...... ....... ....... ....... 9.8 94,200 4,000 42 68 94 100 ....... . ...... . ...... . ...... . ...... 9.8 83,000 2,070 48 70 92 98 98 100 ....... . ...... . ...... 4·0 387 277 20 36 64 92 97 99 100 ....... ....... 15 210 154 ....... ....... 59 65 71 83 90 94 ....... b 16.9 355 2,380 27 56 79 87 89 93 95 98 ....... a82 7,560 1,320 1 4 19 ....... 92 93 93 97 . ...... a82 7,560 1,400 45 62 79 87 90 93 94 97 ....... 148 8,320 1,770 2 6 14 ....... 67 75 87 98 . ...... 148 8,320 1,730 20 34 46 56 64 75 88 97 . ...... 85 8,160 1,730 ....... 4 14 . ...... 61 70 83 92 ....... 85 8,16o 1,760 23 32 44 54 60 68 79 88 . ...... 119 6,230 2,400 29 39 54 63 69 75 85 90 ....... 62 6,340 2,110 ....... 1 lJ 60 63 71 8'.3 94 . ...... 62 6,340 2,920 22 25 38 66 70 80 94 99 ....... 65 5,780 2,390 18 29 41 50 57 65 79 90 . ...... a43 400 325 49 70 76 79 80 89 97 100 ....... a 75 950 611 26 36 47 60 68 78 91 100 . ...... aSS 3,300 2,610 19 22 33 44 55 65 74 96 . ...... a80 3,050 2,580 14 18 27 .38 50 58 70 98 . ...... a 110 675 527 28 32 43 55 67 80 89 96 . ...... . a 320 8,300 1,740 19 27 38 54 75 85 93 98 ....... 247 14,700 18,000 ....... 23 ....... 43 . ...... 83 91 100 . ...... 270 14,000 9,170 ....... 30 ....... 50 ....... 86 97 100 . ....... 491 19,700 18,700 ....... ....... 0 16 63 75 89 98 ....... 491 19,700 12,900 ]J 24 .31 41 62 80 81 98 . ...... 370 JJ,500 10,300 . ...... . ...... 4 36 54 8l 95 99 100 

370 JJ,500 4,780 20 24 31 41 58 81 95 99 100 

1,]JO 44,500 7,420 ....... 43 ....... 64 . ...... 91 98 100 . ...... 1,040 41,100 7,440 ....... 39 . ...... 58 . ...... 86 96 99 100 

1,370 26,500 27,700 ....... 3 5 32 62 79 89 100 ....... 

Methods 

of 

analy'sis 

BW 

BW 

BW 

BW 

BW 

BW 

BN 

BW 

BW 

BW 

BW 

BW 

BN 

BW 

BN 

BW 

BN 

BW 

BW 

BN 

BW 

BW 

BW 

BW 

BW 

BW 

BW 

BW 

SPWCM 

SPWCM 

BN 

BW 

SPN 

SPWCM 

SPWCM 

SPWCM 

BN 

...J 

(X) 
Do ••••••••• 5:.36 p.m. 

Mq' 25······· 12:59 p.m. Do ••••••••• 12:59 p.m. 

Jane 6 ••••••• 2:51p.m. June 10 •••••• 7:50 a.m. 

June 13•••••• 7:1S p.m. June 21 •••••• S:OO a.m. June 29 •••••• 5:50 a:.m. 

Jul¥ 5······· 4:14p.m. 

Do ••••••••• 4:14p.m. 

Jul3r 12 •••••• .3:52 p.m. 

JuJT 19······ 1:.30 p.m. Do ••••••••• 1:.30 p.m. J~ 26 •••••• 10:25 a.m. Aug. 12•••••• SilO a.m. 

Aug. ]3 •••••• 6:.30 p.m. 

Aug. 14······ S:25 a.m. Aug. 15•••••• .3:13 p.m. 

Do ••••••••• .3:13 p.m. Sept. 26 ••••• 5:00 p.m. 

Sept. 27••••• 5:25 p.m. 

Sept. 2S ••••• .3:.30 p.m. Do ••••••••• .3:.30 p.m. 

Sept. 29····· S:55 a ••• Sept • .30••••• S:.30 a.m. 

a Mean dailT discharge. 

b Discharge measurement. 

1,.370 26,500 

1,.320 1'9,000 

1,.320 19,000 

410 5,410 

566 9,500 

.370 4,940 276 6,000 

S2 2,100 

lJ.O 5,200 

lJ.O 5,200 

45 4,.370 

S7 .3.3,700 

S7 .3.3,700 19 951 

56 50,000 

76 .35,000 

67 42,000 

25 6,770 

25 6,770 

a2.3 . 2,200 

a 20 25,000 

a22 29,500 a22 29,500 

25 17,900 a 3S 7,600 

10,.300 16 25 . .3.3 

17,800 ....... ....... 14 

4,110 12 17 21 

6,2SO ....... 21 . ...... 4,970 ....... lS ....... 4,760 ....... 2.3 ....... .3,140 ....... 15 ....... S57 ....... 14 ....... 5,180 ....... .3 6 

2,090 5S 65 74 

10,100 ....... S7 . ...... .34,100 ....... 7 10 

2,520 6.3 79 94 

2,660 .36 47 60 

4,640 ....... 69 ....... 12,400 ....... 57 ....... S,290 ....... 6S ....... 7,2.30 ....... ....... 1 

2,800 6S S6 96 

1,mo ....... so ....... 5,160 ....... S9 ....... .30,200 ....... 4 S2 

6,.380 ....... 92 9S 

7,720 ....... S9 . ...... 4,620 ....... 62 ....... 

43 59 75 89 

21 47 67 80 

.30 41 61 7S 

.32 . ...... 76 92 . ...... ....... 76 96 

.34 ........ 75 96 

21 . ...... 6S 95 

20 . ...... 45 S6 

73 S4 S9 96 

77 so S9 96 

96 ....... 97 

89 97 9S ········ 99 

96 97 9S 100 

6S 76 S9 96 

94 ....... 9S ....... 90 ....... 96 . ...... 94 . ...... 9S ....... 52 91 99 ....... 9S 99 100 ....... 95 ....... 97 . ...... 97 ....... 99 ....... 9.3 96 97 9S 

99 100 ....... . ...... 9S ....... 99 . ...... 74 . ...... 76 ....... 

99 ....... 94 . ...... 91 . ...... 9S 100 100 . . ...... 99 100 

99 100 

9S 100 

99 ....... 99 . ...... ....... ....... 100 ....... ....... . ...... 99 ....... ....... ....... ....... ....... . ...... . ...... ....... ....... ....... . ...... . ...... . ...... . ...... . ...... 99 . ...... ....... . ...... . ...... ....... . ...... . ...... 

!II 

Btl 

BliCK 

SPWCH 

SPWCH 

SAD( 

SN:K 

SPIOI 

BIJ 

BliCK 

SPIOI 

BIJ 

JIOI 

BliCK 

SPWCJ( 

SPWCH 

SPIDI 

SPH 

IIDl 

SPWCII 

SAiCM 

Bill 

BDl 

SPWCH 

SAiCM 

..;J 

U> 
Table 25.--Particle-size analyses of suspended sediment, Powder River near Locate, Mont. 

~thods of anal7ses: B1 bottom withdrawal tube; N, in native waters; W1 in distilJ;ed water; s, sieve; P1 pipette; C, chemically dispersed; . . M, mechanical.ly disperseg( 

Suspended sediment - Water Concen- Concendis- tration of Percent finer than indicated size (mm) Date Time charge tration of suspension 

(cfs) sample anal7zed (ppm) (ppm) 0.002 0.004 0.008 o.o16 0.()31 0.062 0.125 0.250 0.500 1.000 2.000 

1950 

Mar. 3···················· 10:25 a.m. a 50 777 1,170 ..... 17 27 30 42 61 83 98 ..... . .... . .... Do •••••••••••••••••••• 10:25 a.m. a 50 777 1,1.30 17 21 25 32 43 58 78 95 ..... . .... ..... Mar. 24 ••••••••• ·-· •••••••• 4:35 p.m. a 150 9,440 4,&'10 ..... 33 . ..... 43 . .... 71 85 98 100 ..... . .... Mar. )1 ••••••••••••••••••• 4:45 p.m. 200 8,540 5,460 ..... 38 ..... 53 . .... so 92 99 100 ..... . .... Apr. )•••••••••••••••••••• 6:10 a.m. a 31 000 15,500 9,410 ..... 42 ..... 58 . .... so 93 99 100 . .... . .... Apr. 5•••••••••••••••••••• 12:36 p.m. 2,230 9,960 3,2SO 5 8 20 ..... 71 77 83 95 ..... . .... . .... Do•••••••••••••••••••• 12:36 p.m. 2,230 9,960 6,S6o 25 34 47 58 69 74 ss 97 ..... ..... ..... Apr. 7•••••••••••••••••••• 10:25 a.m. 1,7/IJ 12,200 8,760 ..... 41 ..... 60 . .... ss 95 99 100 ..... . .... Apr. 16••••••••••••••••••• 6:15 a.m. 11 0/1) 9,320 6,220 ..... 57 . .... 73 . .... S4 94 98 100 ..... . .... Apr. 18••••••••••••••••••• 6:47 p.m. 745 8,000 8,890 15 16 lS ..... . .... 91 95 99 ..... . .... . .... Do •••••••••••••••••••• 6:47 p.m. 745 8,000 4,69p 47 61 76 84 &'! 90 92 97 ..... . .... ..... Apr. 26 ••••••••••••••••••• 9:15 a.m. 1,060 16,300 4,540 ..... 51 . .... 71 . .... so S9 96 100 . .... . .... ~ 2 ••••••••••••••••••••• 8:22 a.m. 11 0/IJ 11,900 6,720 42 52 63 74 S4 89 96 99 100 ..... ..... Do •••••••••••••••••••• 8:22 a.m. 11 0/IJ ll,900 ll,300 ..... 1 4 76 87 S9 94 98 ..... . .... . .... ~ 9 ••••••••••••••••••••• 9:00 a.m. 1,590 18,300 3,270 ..... 30 . .... 42 . .... 54 66 87 96 99 100 

~ 11 •••••••••••••••••••• 9:30 a.m. 2,020 33,200 7,710 ..... 31 . .... 4h . .... 63 79 98 100 ..... . .... ~ 16 •••••••••••••••••••• 10:30 a.m. 1,120 23,200 7,080 ..... 4h . .... 65 . .... 73 so 94 99 100 . .... May' 18 •••••••••••••••••••.• 8:20 a.m. 1,030 17,200 l.S,IIJO ..... 8 16 S4 94 95 96 99 . .... . .... . .... Do•••••••••••••••••••• 8:20 a.m. 1i030 17,200· 3,350 51 67 77 S6 90 92 95 97 ..... . .... . .... June !•••••••••••••••••••• 6:52 p.m. 1,0/.IJ 5,850 5,420 ..... 6 15 49 56 71 81 96 . .... ..... . .... Do •••••••••••••••••••• 6:52 p.m. 11 0/IJ 5,850 3,470 33 IIJ 46 52 61 75 ss 96 ..... ...... . .... June 8 ••••••••••.•••••••••• 5:45 p.m. 1,070 81 2SO 4,0/IJ ..... 33 . .... 45 . .... 69 86 97 100 . .... . .... June 15••••••••••••••••••• 9:00 a.m. 1,570 16,600 5,570 ..... 37 . .... 51 . .... 85 94 97 98 98 98 

June 26 •• ~··•••••••••••••• 5:45 p.m. 1,070 ll,IIJO 4,310 ..... 24 . .... 34 . .... 54 6S 78 S9 97 100 July 2 •••••••••••••••••••• 5:15 p.m. 450 1,230 737 47 54 60 64 6S 76 S9 96 ..... . .... . .... ~ 11 ••••••••••••••••••• 5:35 p.m. 5l3 15,400 ll,SOO ..... 73 . .... 93 . .... 99 .. -... . .... . .... . .... . .... ~ 12 ••••••••••••••••••• 5:40 a.m. 398 6,210 2,960 ..... 66 . .... 71 . .... 84 . .... . .... . .... . .... . .... July 17··~················ 7:38p.m. 288 2,560 2,010 71 ..... so S4 S9 94 . .... . .... . .... . .... . .... Do•••••••••••••••••••• 7:38p.m. 2SS 2,560 2,430 ..... 4 ll . .... . .... 94 97 100 . .... . .... . .... Ju11 18 ••••••••••••••••••• 5:50a.m. 270 3,520 2,450 ..... 76 . .... sa . .... 98 . .... . .... . .... ..... . .... Julf 21 ••••••••••••••••••• 5:35 a.m. 36o 3,200 2,260 ..... 71 . .... 75 . .... &'! . .... . .... . .... . .... . .... ~ 26 ••••••••••••••••••• 6:05p.m. 192 3,230 2,220 ..... 92 . .... 95 . .... 98 . .... . .... . .... . .... . .... Aug. 11 ••••••••••••••••••• 5:55p.m. 294 22,800 4,640 ..... 74 . .... 91 . .... 96 . .... . .... . .... . .... . .... Aug. 13••••••••••••••••••• 6:05 a.m. 294 23,400 8,410 ..... 76 . .... 97 . .... 97 . .... . .... . .... . .... . .... Aug. 14··················· 6:56 p.m. 106 12,000 12,600 3 3 ..... . .... 93 99 . .... . .... . .... ..... . .... Do•••••••••••••••••••• 6:56 p.m. 106 12,000 2,370 ..... 92 97 98 99 100 . .... . .... . .... ..... . .... Aug. 16 ••••••••••••••••••• 3:30p.m. 282 16,200 6,5SO ..... 73 ..... 93 . .... 98 . .... . .... . .... . .... . .... Aug. 22••••••••••••••••••• 6:30p.m. 63 4,910 3,960 ..... 93 . .... 96 . .... 99 . .... . .... . .... ..... . .... a Mean.~ clischarge. 

Methods 

ot ~ia 

BW 

Ill 

SPIDI 

SPWCM 

SAICH 

BW 

Ill 

SAD( 

SPIDI 

BW 

Ill 

SPIOI 

SPI£K 

BW 

SPIOI 

SAD( 

SPIDI 

Ill 

1101 

Ill 

1101 

SPIDI 

SPIDl 

SAD( 

JJa( 

SPIOl 

SNm 

SN:M 

BW 

SPiDI 

SADl 

SPWCH 

SPWCII 

SAO( 

SPII 

1101 

SPWCH 

SAO( 

ro 

0 
Table 26.--Particle-eize anal.yses of suspended sediment, Middle Fork Powder River above Kqcee, Wyo. 

LNethods of analyses: B, bottom withdrawal tube; w, in distilled water; s, sieve; f, pipette; N, in native waters; c, chemical.ly dispersed; 

M, mechanical.ly diapers~ 

Suspended se<HJDent 

Water Cone en- Concendis- tration of Percent finer than indicated size (:mm) Date Time charge tration of suspension 

(cfs) sample <=r {ppm) 0.002 Oe004 o.oos o.o16 0.031 o.o62 0.125 0.250 o.;oo 

1949 

Nov. 30•••••• 11:37 a.m. 48 269 796 22 32 50 78 96 98 99 100 ....... 1950 

Apr. 6••••••• 9:25 p.m. 60 8,530 10,100 10 10 11 85 100 ....... ....... ....... ....... Do ••••••••• 9:25 p.m. 60 8,530 5,500 45 59 78 93 97 98 99 100 ....... Apr. 1; ...... 7:30a.m. 145 4,550 3,540 ....... 38 . ...... 66 . ...... 99 ....... . ...... ....... Apr. 18 •••••• 11:o6 a.m. 165 3,5lt0 7,100 ....... 22 . ...... ltD . ...... 91 99 100 ....... Mq 6 •••••••• 7:05p.m. 92 11,800 9,610 ....... 6; ....... 90 . ...... 100 . ...... . ...... . ...... May" 9········ 5:30p.m. 103 19,700 15,800 ....... 55 . ...... 82 . ...... 99 100 ....... . ...... Mq 15······· 11:45 a.m. 260 2,850 4,600 ....... . ...... . ...... 20 34 60 84 . 97 ....... - 16 ••••••• 3:24p.m. 315 4,150 2,930 6 9 17 20 36 66 93 99 100 

Do ••••••••• 3:24p.m. 315 4,150 1,910' 15 16 19 26 4.3 72 93 99 100 

Mq 24······· 11:12 a.m. 467 2,310 4,040 . ...... l.S ....... 34 . ...... 70 as 98 100 

Au&• 12 •••••• 1t20 p.m. ~ 2,720 2,330 ....... 66 . ...... 93 ....... 100 ....... . ...... ....... 

Table 27.-Particle-eize anaJ¥ses of suspended sediment, Middle Fork Powder River near Kqcee, Wyo. 

,Liethods of ana.:cyses: s, sieve; P, pipette; w, in distilled water; c, chemic~ dispersed; M, mechanically di~persed; N, in native wateri/ 

Suspended sec:Ument 

Water Cone enDate Time dis- Cone en- tra.tion of Percent finer than indicated size (mm.) 

charge tration ot suspension (cfs) ;~ ~zed 

(ppm) 0.002 0.004 o.oo8 o.ol6 0.031 o.o62 0.125 Oe250 o.;oo 1.000 

1950 

Mar. 26 •••••• StOO p.m. a 125 1,500 980 ....... 82 ....... 97 ....... lOO ....... . ...... . ...... . ...... Apr. 6 ••••••• 8z00 a.m. 145 1,790 3,300 ....... 80 ....... 97 . ...... lOO . ...... ....... . ...... . ...... Apr. 15•••••• 6zoo p.m. 316 5,320 2,310 ....... 48 ....... 83 ....... 100 ....... ······· ....... . ...... Mq 17······· 2t25 p.m. 1,330 15,100 10,900 1 2 10 ltD 65 S9 92 98 100 ....... Do ••••••••• 2:25p.m. 1,330 15,100 5,600 l.S 23 30 40 56 76 93 98 100 ....... ~ 18 ••••••• 1:00 p.m. 1,540 12,lt00 8,130 ....... 21 ....... 48 ....... 73 93 98 100 . ...... Mq 24······· 3:25p.m. 1,060 6,100 3,140 ....... 16 ....... 30 . ...... 62 sa 97 100 . ...... Mq 31 ••••••• 6:00 p.m. 3~ 1,190 306 ....... 13 ....... 33 ....... 50 . ...... ....... ....... . ...... June 9••••••• 7:00 a.m. 332 790 3,SOO ....... 29 ....... 42· ....... 74 sa 93 96 98 

Jul;y 6 ••••••• 10:57 a.m. ;a 517 1,180 ....... 40 ....... 83 . ...... 97 . ...... . ...... ....... . ...... a Mean ~ discharge. 

Metboda 

of ~is 

Elf 

SPH 

BWCM 

SPWCM 

SPtiCM 

SPWCM 

SPWCM 

BWCM 

SPB 

SPWCM 

SPWCM 

SPlOI 

Methods 

of 

ana:qsis 

SPWCM 

SPWCM 

SPIDl 

SPH 

SPWCM 

SN2I 

SPWCM 

SPWCM 

SPWCM 

SPiD! 

0> 

..... 
,Liiet.hods or ~ses: 

Date Time 

1950 

Apr. 9••••••• 3:36 p.m. 

Apr. 16 •••••• 8:20a.m. 

Apr. 17 ...... 9:20 a.m. Apr. 18 •••••• 8:07 a.m. Apr. 20 •••••• 1:.:18 a.m. 

Ma1' 10 ••••••• 3:16 p.m. ~ 12 ••••••• 4:10 p.m. Ma1' 1,3 ••••••• 4:00p.m. Ma1' 18 ••••••• 4:17p.m. Do ••••••••• 4:17 p.m. 

~ 25······· 10:42 a.m. 

June 1 ••••••• 5:20 p.m. 

June 6 ••••••• 4:28p.m. 

June 11 •••••• 8:25 a.m. Aug. 12 •••••• 7:10 a.m. 

Aug. lJ•••••• 7:30a.m. 

Do ••••••••• 6tl0 p.m. 

Table 28.-Particle-size ~es of suspended sediment, Crazy W~ Creek near Arvad.&, Wyo. 

B, bottom withdrawal tube; W, :1n disti.l.l.ecl water; s, sieve; P, pipette; c, chemic~ dispersed; M, mec~aJ.l¥ dispersed 

H, :1n native wateri/ 

Suspended. sed:flnent 

Water Cone en- Cone en- Percent finer than indicated size (Dill) dis- tration ot Metboda 

charge tration or suspension .. ot 

(c:f's) sample 

(ppm) ~ed 

(ppm) 0.002 0.004 o.oos 0.016 0.031 o.o62 0.125 0.250 0.5()0 ~ 

82 1,160 1,120 ....... 68 82 92 97 98 99 100 ....... Ill 

140 3,200 2,470 ....... 6o . ...... 77 . ...... 95 9S 100 ....... SN2 

192 7,620 5,820 ....... u . ...... 70 . ...... 96 99 100 . ...... SA«:M 

121 4,300 3,230 ....... 52 . ...... 75 . ...... 91 95 100 ....... SPWCH 

124 1,900 3,770 36 45 57 68 78 86 92 99 100 SPICH 

1.00 1,750 3,720 ....... 73 . ...... 87 ·····~· 94 ....... ....... . ...... SPWCK 

178 6,360 5,140 ....... 6o ....... so . ...... 94 98 1.00 . ...... SPiiDI 

132 9,74D 8,180 ....... 74 . ...... 91 . ...... 96 97 99 1.00 SPWCH 

396 12,600 11,200 2 3 l3 54 72 89 ....... ee•••••· . ...... SPfi 

396 12,6oo 4,480 ....... 32 4D 53 68 81. 92 97 . ...... mal 

285 3,041) 4,920 ........ 31 . ...... 45 . ...... 74 92 99 1.00 SPWCM 

176 1,210 540 . ...... 39 ....... 49 . ...... 67 85 97 ].()() SPWCH 

140 886 1,641) ....... 41 ....... 57 . ...... 74 89 98 100 SAD{ 

180 2,o6o 1,230 . ...... 36 . ...... 47 . ...... 71 88 98 100 SF1iCH 

18 15,400 6,630 ....... 74 . ...... 97 . ...... 100 . ...... . ...... . ...... SPfD{ 

73 54,000 5,520 ....... 56 ....... 87 . ...... 93 . ...... . ...... . ...... SN::M 

15 12,400 5,4&:> . ...... 74 . ...... 9.3 ....... 99 . ...... . ...... . ...... SPiCM 

Table 29.-Particle-size ana~es or I!Jilspended sed1ment, Clear Creek near Arn.da, Wyo. 

J54,ethods or ~es: s, sieve; P, pipette; w, in distilled water; c, chemical]¥ dispersed; H, mechaniea:l.]Jr dispersed; B, bottom withdrawal wbi/ 

Suspended sediment 

Water Concen- Concen- Hethods dis- traticm of Percent riner than indicated size (m) Date TiM charge tration or 8\18l)en81on of 

(ere) sa~p1e ~ed 0.002 0.004 o.oos 0.016 0.031 0.062 0.125 0.250 0.500 1.000 anal.Tsia 

(ppm) (ppm) 

1950 

Mq 18 ••••••• 7al6 p.m. 444 895 2,490 ....... 50 ....... 76 ....... 95 97 99 1.00 . ...... SAD( 

Hq 25······· 2:48 p.m. 74/J ass 2,241) ....... 34 ....... 54 ....... 81 90 97 99 100 SPtDl 

June a ••••••• 9t00 a.m. 1,21.0 2,670 1,660 ....... 34 ....... 47 . ...... 71 so 92 99 100 SPV.::M 

June 1,3 •••••• 11:15 a.m. 904 959 2,150 ....... 2.3 . ...... 42 . ...... 76 91 97 100 . ...... SPWCM 

Aug. 13•••••• 1:30 p.m. 99 1,44/J 1,120 69 82 94 100 ....... . ...... . ...... ....... . ...... . ...... liCK 

0> 

"" 
83 

Table 30.--Specific weight and median diameter of reservoir sediment 

Source 

Lake Clarmore, Rogers County, Okla. ll··~···~··· 

High Point Reservoir, High Point, N ~ C. ]j ...... 

Wills Point Reservoir, Wills Point, Tex. ll••••• 

Grisham Lake, Washington County, Mo. ll········· 

Kirk Lake, Allen County, Kans. ll····••••••••••• 

Lancaster Reservoir, Lancaster, S.C. ll•••••••• 

Mountain Lake, Wayne County, Mo. ll·········•••• 

Moran Reservoir, Allen County, Kans. ll········· 

Neosha County State Lake, Kans. ll•••••••••••••• 

Shepherd Mountain Lake, Iron County, Mo. ll····· 

See footnotes at end of table, p. 85. 

Sample number 

FC 39 CM-1 

FC 39 CM-2 

FC 39 CM-3 

FC 39 CM-4 

FC 39 CM-5 

FC 39 CM-6 

FC 39 CM-7 

FC 39 CM-8 

F'C 39 CM-9 

FC ~ CM-10 

FC 38 HPR-6 

FC 38 HPR-9 

FC 38 HPR-10 

FC 38 HPR-13 

FC 38 HPR-14 

FC 38 HPR-16 

FC 38 HPR-18 

FC 38 HPR-21 

FC 38 HPR-22 

FC 38 HPR-23 

1 

2 

3 

4 

5 

6 

7 

8 

9 

FC 39 GR-1 

FC 39 GR-2 

FC 39 GR-3 

FC 39 KR-1 

FC 39 KR-2 

FC 38 LA-1 

FC 38 LA-2 

FC 38 LA-3 

FC 38 LA-4 

FC 38 LA-5 

FC 38 LA-6 

FC 38 LA-7 

FC 38 LA-8 

FC 39 MO-l 

FC 39 M0-2 

FC 39 M0-3 

FC 39 MN-1 

FC 39 MN-2 

FC 39 MN-3 

FC 39 MN-4 

FC 39 MN-5 

FC 39 MN-6 

FC 39 NE-1 

FC 39 NE-2 

FC 39 NE-3 

FC 39 NE-4 

FC 39 NE-5 

FC 39! SH-1 

FC 39' SH-3 

Specific weight Median diameter 

(lb per cu ft} (mm} 

43 

45 

40 

44 

51 

55 

54 

63 

51 

65 

59 

62 

68 

41 

60 

44 

64 

45 

37 

40 

51 

53 

53 

59 

54 

86 

85 

45 

52 

53 

56 

117 

42 

55 

54 

70 

70 

79 

68 

39 

62 

57 

41 

66 

50 

38 

52 

62 

49 

43 

37 

30 

36 

38 

45 

43 

85 

0.0017 

.0018 

.0019 

.0026 

.0054 

.0046 

.0066 

.0116 

.0038 

.0290 

.0215 

.0338 

.0016 

.0032 

.0105 

.0130 

.0012 

.0163 

.0055 

.0008 

.0030 

.0026 

.0035 

.0027 

.0022 

.0120 

.0135 

.0012 

.0014 

.0096 

.0125 

.3330 

.0024 

.0054 

.0020 

.0064 

.0166 

.0248 

.0117 

.0118 

.0163 

.6070 

.0076 

.0244 

.0137 

.0025 

.0020 

.0046 

.0177 

.0061 

.0023 

.0015 

.0021 

.0055 

.0044 

.0130 

.0109 

.4900 
84 

Table 30.--Specific weight and median diameter of reservoir sediment•-Continued 

Source Sample number Specific weight Median diameter 

( lb per cu ft) (mm) 

Lake Lee, Monroe, N.C. 1/ ..................... . FC 38 LE-1 62 0.0032. 

~ 38 LE-2 60 .0030 

~ 38 LE-3 59 .0040 ~ 38 LE-4 59 .0060 

FC 38 LE-5 60 .0048 

FC 38 LE-6 61 .0052 

FC 38 LE-7 66 .0052 

FC 38 LE-8 73 .0084 

Lake Marinuka, Galesville, Wis.!/·············· FC 39 MA-l 40 .0024 ~ 39 MA-2 52 .0022 ~ 39 MA-3 56 .0046 ~ 39 MA-4 55 .0052 

~ 39 MA-5 60 .0076 

FC 39 MA-6 70 .0070 

~ 39 MA-7 63 .0077 

FC 39 MA-8 60 .0099 

~ 39 MA-9 66 .0126 

~ 39 MA-10 80 .0274 

~ 39 MA-ll 77 .0136 ~ 39 MA-12 69 .0175 

~ 39 MA-13 85 .0290 

FC 39 MA-14 87 .0220 

Arrowrock Reservoir, Idaho~; ••••••••••.••••.••• 1 53.9 .0260 

2 87.9 .1580 

3 60.4 .1050 

4 44.2 .0046 

5 102.2 .3580 

6 64.2 .1700 

7 52.7 .0071 

8 61.5 .0176 

10 47.7 .0310 

11 57.9 .0234 

12 52.3 .0208 

13 58.8 .0445 

14 57.3 .0265 

15 48.3 .0275 

16 112. .. 5 .8800 

18 52.1 .0114 

Guernsey Reservoir, Guernsey, Wyo.~/ ........... . 1 30.7 .0020 

2 32.4 .0092 

3 ................ . .............. 4 43.1 .0028 

5 ................ . .............. 

6 41.7 .0064 

7 50.1 .0046 

8 56.5 .0067 

9 54.6 .0022 

10 76.5 .0111 

11 125.4 .8950 

Tongue River Reservoir, Sheridan, Wyo.~/ ••••••• 1 72 .0260 

2 78 .0240 

3 81 .0240 

7 43 .0030 

8 44 .0017 

9 65 .0130 

10 74 .0140 

11 83 .0220 

12 37 .0028 

12A 42 .0018 

13 .55 .0056 

14 63 .0130 

Se~ footnote~ at end of table, p. 85. 
85 

Table 30.--Specific weight and median diameter of reservoir sediment--Continued 

Source 

Tongue River Reservoir, Sheridan, Wyo. ~/-~on •• 

Altus Reservoir, Altus, Okla. ~/·••••••••••••••• 

Salt Creek Reservoir south of Midwest, Wyo •••••• 

Snodgrass Ranch Reservoir, Wyo., SEi sec. 22, 

T. 40 N., R. 81 W ••••••••••••••••••••••••••••• 

Snod~rass Ranch Reservoir, Wyo,, (upper end) 

NE4 sec. 20, T. 40 N., R. 81 W •••••••••••••••• 

Snodgrass Ranch Reservoir, Wyo., SWi sec. 8, 

T. 39 N., R. 81 W ••••••••••••••••••••••••••••• 

Darlington Reservoir, Wyo., sec. 13, T. 43 N., 

R. 67 W.: 

upper end ••••••••••••••••••••••••••••••••••••• lower end ••••••••••••••••••••••••••••••••••••• 

Darlington Reservoir, sec. 36, T. 45 N., 

R. 67 W.: 

upper end . ..............•.••.•.........•..•••• 

lower end .........•....•.. ..•....•.•....••.••• 

East Slagle Reservoir, near Lance Creek, Wyo.: 

upper end ••••••••••••••••••••••••••••••••••••• lower end ••••••••••••••••••••••••••••••••••••• 

1/ Collected by Soil Conservation Service. 

g/ Collected by u. s. Bureau of Reclamation. 

Sample number 

15 

16 

17 

18 

19 

1 

8 

4 

11 

Al 

A3 

A6 

12 

10 

A4 

A2 

AlO 

3 

AS 

66 

67 

68 

69 

70 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

3297 

3298 

3299 

3300 

3287 

3288 

Specific weight Median diameter 

( lb per cu ft) (mm) 

64 0.0096 

79 .0500 

70 .0160 

92 .0860 

90 .0220 

26.7 .0054 

53.6 .0220 

36.5 .0150 

91.6 .1500 

106.6 .1350 

45.8 .0058 

65.4 .0620 

80.8 .0350 

54.3 .0036 

57.9 .0260 

32.8 .0071 

39.6 .0038 

43.1 .0038 

49.3 .0036 

74.7 .0535 

75.8 .0500 

79.1 .0470 

73.2 .0425 

79.8 .0415 

46.7 .0034 

52.0 .0043 

45.9 .0041 

46.5 .0043 

38.4. .0033 

50.6 .0024 

49.0 .0026 

46.7 .0027 

38.:3 .0029 

28.1 .0030 

60.5 .0063 

58.5 .0090 

62.8 .0100 

64.1 .0160 

67.7 .0152 

71.6 .0210 

58.3 .0087 

65.7 .0028 

53.0 .0026 

63.1 .0163 

60.4 .0168 
Specific 

Date weight 

Table 31.--Particle-aize ana:]Jrses of sedilllents deposited in reservoirs, Powder River drainqe basin 

Lfletbods of ana:]Jrsis: s, sieve; P, pipette; C, chemical:]Jr disper~ 

Deposited ~nt 

Percent finer than indicated size (mm) Methods 

of Remarks 

(lb per cu tt) 0.004 o.ooe 0.016 0.031 0.062 0.12$ 0.2$0 o.soo ana:]Jrsis 

Sept. 1949 •• 74.7 24 

llc> •••••• 7$.8 28 

Jlo •••••• 79.1 26 

llo •••••• 73.2 27 

llo •••••• 79.8 27 

llo •• •••• h6.7 $3 

Ilo •••••• $2.0 48 

Do •••••• 4.$.9 so 

Do •••••• 46.$ 49 

llo •••••• 36.4 ss 

Ilo •••••• $0.6 70 

llo •••••• 49.0 60 

I>o •••••• 46.7 $9 

Do •••••• 38.3 $8 

Ilo •••••• 28.1 58 

IJc) •••••• 60.$ 43 

l)o ••• ••• sa.; 38 

l)c) •••••• 62.8 32 

Do •••••• 64.1 2$ 

Do ••••• t! 67.7 26 

Specific 

Date weight 

(lb per cu tt) 0.004 

1949 

Aug. 6 ••• 92.6 ...... Ilo ••••• 90.9 ...... llo ••••• 91.$ ...... llo ••••• 88.5 ...... Do ••••• 94.3 ...... llo ••••• 83.6 s 

IO ••••• 81.9 7 

Do ••••• 76.3 7 

Do ••••• 83.7 7 

28 33 39 $7 93 100 ...... SPC Salt Creek Reservoir north ot Midwest, Wyo. 

31 36 42 59 94 100 ...... SPC Do. 

31 37 42 $8 91 99 100 SPC Do. 

31 36 43 63 9$. 100 ...... SPC Do. 

32 38 4S 61 92 99 100 SPC Do. 

68 80 90 97 99 100 ...... SPC Snodgrass Ranch Reservoir, ~yo., SEi sec. 22, T. 40 H., R. 81 w. 

61 74 85 96 100 ...... ...... SPC Do. 

6$ 78 88 96 100 ...... ...... SPC Do. 

64 71 86 93 100 ...... ...... SPC Do. 

72 86 94 97 100 ...... . ..... SPC Do. 

76 88 94 98 100 ...... . ..... SPC Snodgrass Ranch Reservoir, Wyo., NEt sec. 20, T. 40 N., R. 81 w. 

77 89 96 97 99 100 ...... SPC Do. 

74 84 90 96 98 100 ...... SPC Do. 

74 86 94 97 100 ...... ...... SPC Do. 

74 86 94 98 100 ...... ...... SPC Do. 

54 63 73 89 100 ...... ...... SPC Snodgrass Ranch Reservoir, rlyo., swt sec. 8, T. 39 N., R. 81 w. 

48 $9 71 89 100 ...... ...... SPC Do. 

4S $9 73 92 100 ...... ...... SPC Do. 

38 so 64 88 100 ...... ...... SPC Do. 

38 51 64 88 100 ...... ...... SPC Do. -- --·---L__ 

Table 32.--Particle-aize ana:]Jrses of stream-bed material, Poillder River drainage basin 

Lflethods of analysis: s, sieve; P, pipette; c, chemical:]Jr disperseg 

Deposited sediment 

Percent finer than indicated size (mm) Methods 

or Remarks 

0.008 0.016 0.0)1 0.062 0.125 0.2$0 0.$00 1.000 2.000 4.000 analysis 

. . . . . . . ..... . ..... 11 33 45 71 93 99 100 s South Fork Fbwder River near Kaycee, Wyo. ...... . . . . . . . ..... 4 9 23 $3 72 63 93 s Do. ...... ...... ...... 6 1$ 22 48 76 66 91 s l.lo. 

...... . ..... . ..... 3 6 35 71 84 90 9$ s Do. ...... . ..... ...... 0 2 6 1$ 63 75 66 s Do. 

s 7 11 29 48 $4 76 94 100 ...... SPC Do. 

6 10 15 33 91 100 ...... ...... ...... ...... SPC Middle Fork Powder River near Kaycee, ~yo. 

7 10 19 39 90 99 100 ...... ...... ...... SPC Do. 

7 10 14 34 91 100 ...... ...... ...... . ..... SPC Do. 

0> 

en 
Do ••••• 68.7 8 9 l3 20 38 90 

lJo ••••• 82.8 7 6 12 20 31 47 

Aug. a ••• 93.9 ...... ...... ...... . . . . . . 2 9 

Ilo ••••• 87.1 . . . . . . . . . . . . ...... ...... 2 -a 

J)o ••••• 86.7 ...... ...... ...... ...... 3 14 

Do ••••• 74.9 ...... ...... ...... ...... 2 15 

Do ••••• 86.6 ...... ...... ...... ...... 2 16 

Aug. 24 •• 82.6 ...... . ..... ...... ...... 1 6 

.Do ••••• 94.4 ...... ...... ...... ...... 2 2 

I>c> ••••• 90.7 ...... ...... ...... ...... 2 2 

Do ••••• 89.4 . ..... ...... ...... ...... 1 2 

.Do ••••• 81.3 . . . . . . ...... ...... . ..... 1 2 

Aug. 8 ••• 86.6 ...... ...... ...... . ..... 2 .1 

.l)c) ••••• 86.7 ...... . ..... . ..... ...... 3 14 

Ilo ••••• 91.7 ...... . . . . . . . ..... ...... 6 22 

))c) ••••• 84.5 ...... ...... ...... . . . . . . 3 16 

Do ••••• 86.5 ...... ...... ...... ...... 2 15 

Aug. 24 •• 73.1 ...... ...... ...... ...... 7 21 

))c) ••••• 70.8 ...... ...... ...... ...... 9 21 

Do ••••• 85.9 ...... . . . . . . ...... ...... 3 17 

))c) ••••• 90.6 ...... . ...... . . . . . . . . . . . . 3 17 

Do ••••• 82.3 ...... ...... . . . . . . ...... 1 5 

Aug. 26 •• 92.3 ...... ...... ...... ...... 1 4 

Do ••••• 84.2 ...... ...... ...... -....... .... 1 s 

Ilo ••••• 92.6 ...... . . . . . . ...... ...... 1 17 

Do ••••• 96.0 ...... ...... ...... ...... 0 5 

Do ••••• 73.h 16 20 24 27 42 72 

Do ••••• 71.1 15 18 21 24 bO 69 

Aug. 26 •• 80.8 16 23 39 60 82 99 

J)o ••••• 90.1 8 11 16 23 37 61 

llo ••••• 73.8 24 29 34 43 60 94 

Do ••••• 78.1 20 2$ 32 40 54 82 

Do ••••• 6$.8 28 37 $3 72 86 98 

Do ••••• 90.3 . . . . . . ...... . . . . . . . .. . . . 2 16 

Do ••••• 93.6 ...... ...... ... . . . . . ...... 2 . 15 

Ito ••••• 92.5 ...... ...... . . . . . . ...... 2 12 

llo ••••• 96.3 ...... ...... . ..... ...... 1 9 

l>o ••••• 91.1 ...... . ..... ...... . ..... 1 12 

- Aq. 30 •• . 95.2 ...... ...... . ..... ...... 3 15 

.Do ••••• 91-.0 ... ·--. ...... ...... . ..... 4 27 

1)c) ••••• 103.9 ...... ...... ...... ...... 4 23 

Do ••••• 97.2 ...... ...... ...... ...... 4 22 

J)c) ••••• 10$.6 ...... ...... ...... ...... 2 17 

100 ...... ...... ...... 100 ...... . . . . . . ...... 90 100 ...... ...... 88 100 ...... ...... 87 99 99 100 

94 100 ...... ...... 94 100 ...... ...... 52 89 96 98 

6 56 91 91 

6 57 90 96 

5 52 92 98 

7 62 95 99 

40 90 99 100 

so 94 99 100 

68 97 100 . . . . . . 43 92 99 100 

4S 93 99 100 

53 95 100 ...... 55 94 99 100 

73 98 100 . ..... 77 91 99 100 

55 95 99 100 

36 74 92 94 

34 73 94 97 

65 92 99 100 

30 72 94 98 

93 100 , ..... ...... 92 99 100 ...... 100 . . . . . . ...... ...... 98 100 ...... ...... 100 ...... . . . . . . ...... 97 100 ...... ...... 100 ...... ...... ...... 64 94 99 100 

63 86 98 99 

S4 88 97 99 

46 73 88 92 

62 90 98 99 

62 78 87 93 

65 80 94 97 

49 61 81 92 

51 66 84 93 

40 51 81 92 

. ..... SPC 

...... SPC 

...... s ...... s' . ..... s ...... S· . ..... s 

100 s 

99 s 

98 s 

100 s 

100 s 

...... s . ..... s . ..... s . ..... s ...... s 

...... s . ..... s ...... s . ..... s . ..... s 

96 s 

98 s . ..... s 

99 s . ..... SPC ...... SPC 

...... SPC· 

...... SPC 

...... SPC ...... SPC ...... SPC 

...... s 

100 s 

99 s 

93 s 

100 s 

95 s 

99 s 

97 s 

98 s 

95 s 

Do. 

.Do. 

Salt Creek near Sussex, Wyo. 

Do. 

Do. 

Do. 

Do. 

Crazy Woman Creek near Arvada, Wyo. 

Do. 

Do. 

Do. 

Do. 

Powder River at Sussex, Wyo. 

Do. 

Do. 

Do. 

Do. 

Powder River at Arvada, Wyo. 

Do. 

Do. 

Do. 

Do. 

Powder River near confluence with Clear Creek. 

Do. 

Do. 

,Do-t 

Do. 

Do. 

Powder River near Moorhead, Mont. 

Do. 

Do. 

Do. 

Do. 

Powder River near Mizpah, Mont. 

Do. 

Do. 

Do. 

Do. 

Powder River near Powderville, 12ont • 

Do. 

Do. 

Do. 

Do. . 

ro 

....:2 
Table 33 .-Ana:cyses of water in the Pow:ler River drainage basin in 'i.'Yoming and •lontana 

,Lina:l.ytical results in parts per million except as indicateg? ~ Specific Daily conduct- Cal- Mag- PoDate of mean SUica Iron Bico.r- Chlo- Fluo- NipH ance Sodium tas- Sulfate 

collection discharge (micro- (Si02) (Fe) cium nesium (Na) siwn bonate (S04) ride ride trate 

(cfs) mhos/em (Ca) (1-Ig) (K) (HC03) (Cl) (F) (!103) 

at 25 C) 

Powder River at Sussex, w,ro. 

Nov. 301 1949 ... •.......• ?.a 1,500 l4 0.04 127 60 152 240 548 87 o.6 3·9 Jan. 6, 1950 •••• ......... 7·7 2,030 16 .06 191 66 2l3 2SS 758 127 .6 5·5 Jan. 31 ••••••••• •....•... 7·5 l,S.)o 22 . ... 282 63 48 304 6z.J 102 .6 2.8 

Mar. 3·········· 115 7.8 1,740 23 .02 154 53 184 218 645 103 .a 5.2 

Apr. 6•••••••••• 301 7·7 1,990 23 .10 l44 49 241 2l6 750 84 .6 10 

May 6 ••••••••••• 60S 7.6 2,600 l3 .10 160 47 373 196 1,100 67 .6 1.2 

June 7•••••••••• 2S2 7e4 790 l4 .02 ao 24 68 161 255 33 ·4 2.1 

Jul.y' 6 •••••••••• 109 7e2 3,510 15 .06 259 S7 490 219 1,640 118 .s 3.6 Aug. 2 ••••••••.•• ll 7.8 3,030 12 .04 248 sa 342 226 1,190 210 .9 .a 

Sept. a ••••••••• 24 7·7 3,660 ll .04 321 109 467 238 1,540 327 1.1 .a 

Powder River at Arvada, Wyo. 

Mlq' 3, 1946 ..... 500 7·7 704 ...... o.o; 94 24 37 2o6 203 2l 0.3 4·0 June 1 •••••••••• 530 8.2 1,000 ...... .o; lll 34 85 190 385 30 ·4 3.0 Jul7 20 ••••••••• lS4 8.2 1,770 ...... .o5 239 55 155 lSl 922 35 .8 1.0 

Sept. 9••••••••• 230 7.8 l,S3o ...... .o5 341 68 84 lS6 11 080 21 ·7 .6 Oct. 2 •••••••••• 90 8.2 1,520 ...... .l.O 165 58 153 a20S 676 75 .8 1.0 

Apr. 4, 1947•••• 261 8.2 1,610 12 .10 149' 47 16a 184 682 JJ, ·4 4·0 MaT 1 ••••••••••• 814 8.2 1,500 17 .o; 153 51 193 b 196 756 42 ·4 4·4 

June 4•••••••••• 1,040 8.1 l,OSO l4 .os 106 30 120 154 462 26 ·5 4·0 

June 29••••••••• 494 8.2 1,150 l4 .10 99 30 127 w 477 2l .8 4·0 

Aug. 20••••••••• 1.5 8.4 2,500 l4 .04 253 101 288 c 213 1,240 146 ·4 .6 

July 14, 1948··· 2,110 6.6 1,860 19 .;o 271 64 lll 236 91.6 23 ·5 ·3 Nov. l•••••••••• 121 8.0 1,620 9.0 .02 157 55 162 220 666 66 .7 2.6 

Nov. 30••••••••• 120 7.9 2,070 12 .o5 209 85 214 .311 924 S2 .6 2.9 

Mar. 3, 1949···· 1,500 7·3 1,360 9.8 .04 l22 35 125 124 552 29 ·4 3.0 Apr. 12 ••••••••• .31.,2 7·5 2,300 14 .02 175 68 298 207 l,06o 61 .8 3·7 

June 1 •••••••••• 324 7·5 1,:no 1.3 .02 123 .34 147 179 532 z.J .7 3.2 July 6 •••••••••• 214 7·.3 1,820 15 .02 201 57 162 210 800 57 ·5 1.3 

Dec. 7•••••••••• .30 8.0 2,290 17 .04 214 92 239 .312 975 lll .6 5.1 

Jan. 3, 1950•••• 22 7.9 2,650 25 .... 168 108 362 4l6 1,080 127 .6 6.3 

Feb. 7•••••••••• 45 7.6 2,600 24 .02 235 64 367 312 l,l6o 124 .6 7.8 

Mar. 2 •••••••••• 90 7.8 1,560 20 .02 1.30 45 172 lSO 603 7.3 ·4 4·7 Apr. 6 •••••••••• 25S 7·7 1,830 19 .04 159 54 174 220 675 77 .6 4·5 

May 15·········· 482 7.6 2,ll0 J.S .l.O 182 5.3 262 166 1,010 37 .6 1.4 June 6 •••••••••• 402 7.7 1,020 14 .04 95 28 90 160 355 31 .6 3·5 JulJr S•••••••••• 128 7·3 1,550 ll .04 173 52 147 150 760 34 ·5 3.2 

Aug. 3·········· 6.0 7.6 2,320 12 .02 217 112 209 244 1,170 24 ·.3 1.2 

Sept. 28 •••••••• 2l 7.2 2,690 14 .02 244 90 .313 206 1,.330 7l .a 2.8 

Dis- Boron 

(B) solved 

solids 

. ... l,llO . ... 1,520 

0.30 1,310 .... 1,280 ~25 1,410 

.20 1,S6o 

.10 572 .... 2,720 .26 2,200 

.30 2L~o_ 

. ... 5Cfi . ... 789 . ... 1,590 . ... 1,690 . ... 1,230 

.19 1,200 

.29 1,310 .28 SlS 

.20 872 

·33 2,150 

.... 1,520 

.12 1,230 .28 1,600 

.Cf} 9.3S .... 1,700 

.... 985 .... 1,400 .)0 1,810 . ... 2,000 ..... 2,140 

.os 1,140 

.30 1,270 .... 1,650 .... 7.36 .... 1,260 

·35 1,870 .... 2,170 

Hardness as CaC03 

Total Ilion- carbonate 

564 367 7~ 512 

963 7l4 

602 423 

561 384 

593 432 

298 166 

1,000 820 

900 795 

:J.,250 1,060 

333 164 

417 261 

822 674 

1,130 977 

650 479 

565 U4 

591 z.JO 

300 262 

370 253 

1,050 870 

9.39 745 

618 z.JS 

S7l 616 

MS .346 

7l6 51/> 

447 300 

736 564 

913 657 

86.3 522 

850 594 

510 362 

619 1.:39 

672 536 

.352 221 

61/> 523 

1,000 soo 

978 009 

Percent 

sodium 

37 

38 

10 

40 

~ 

58 

33 

51 

1.:3 

45 

19 

31 

29 

14 

34 

39 

42 

40 

1.:3 

37 

20 

36 

35 

38 

48 

1.,2 

32 

36 

48 

~ 

42 

.38 

JJ, 

36 

3.3 

.31 

41. -

()) 

ro 
Powder River near Locate. Mont 

Nov. 14, 1945 ... 125 8.0 1,760 8.4 o.cn 162 65 178 5.2 .302 717 42 0 • .3 ,3.2 0.04 1,410 672 424 .37 

Aug. .311 1948. ~ • 58 7.6 1,910 14 .02 179 60 204 244 860 28 .6 .s .18 1,470 693 49.3 .39 

Oct. 27••••••••• 258 7·9 1,960 18 .04 176 62 245 2.38 924 48 ·5 1.5 .... 1,590 694 499, 43 

Dec. 21 ••••••••• 80 8-.0 2,220 18 .06 214 95 187 .374 904 56 ·5 .3·9 .19 ·1,670 924 617 .31 

Feb. 271 1949••• 80 7·5 1,630 16 .02 151 62 134 .304 580 II> ·4 3.8 .oo 1,150 6.32 .38.3 32 

Mar. 7·········· 11,100 7.7 640 9.0 .02 56 16 55 147 182 7.0 ·5 3·9 .17 433 206 85 37 

Apr. 26 ••••••••• 592 7.8 1,870 13 .02 111> 6.3 199 238 776 35 ·4 2.6 .... 1,350 624 429 41 

~ 24·········· l,JI>o 7.5 944 14 .02 88 26 76 168 .312 18 ·4 2.3 .... 685 327 189 34 

June 27••••••••• 67.3 7.6 810 14 .02 72 18 75 130 276 14 ·5 2.2 .... 58.3 254 147 .39 

July 18 ••••••••• 286 7.6 2,520 17 .02 219 75 272 236 1,130 52 .6 .6 .... 1,880 855 661 41 

Dec. 5·········· 220 7.7 1,900 lJ .... 168 75 18.3 .300 775 47 ·4 4·8 .... 1,410 728 482 .35 

Feb. 8, 1950 •••• .1 6.9 3,700 .38 .02 322 145 512 685 1,710 116 .6 7.0 .... 3,190 1,400 8.38 44 

Mar. ) •••••••••• 50 7·5 949 12 .10 80 28 100 156 .357 21 .2 2.9 .... 7.30 .315 187 41 

Apr. 6 •••••••••• 1,630 7-7 891 21 .10 69 23 96 170 305 12 ·4 1.3 .20 678 267 128 44 Mar 2 ••••••••••• 1,000 7·7 1,120 14 .20 72 25 147 204 .388 20 .6 1.4 .... 834 28.3 116 5.3 

May 9 ••••••••••• 1,510 7·7 1,610 14 .10 116 41 214 208 680 28 ·5 4·0 .... 1,200 458 287 50 

June 6 •••••••••• 870 8.0 856 16 .04 75 24 80 156 295 15 .6 1.5 .... 600 286 158 38 

June 26 ••••••••• 1,030 7.6 767 13 .04 68 21 72 140 265 15 .2 1.4 .20 552 256 141 38 

July 5·· •••••• •• 258 7.6 1,220 17 .04 10.3 30 147 199 485 22 ·5 .7 .... 948 381 218 46 

July 17········· 288 7·5 1,430 12 .02 ll3 40 149 208 540 24 ·3 3.6 .20 984 M6 275 42 

Aug. 2•••••••••• 87 7.6 1,9.30 17 .02 155 62 213 234 835 28 ·4 1.0 .30 1,430 640 448 42 

----

Sept. 4••••••••• 10 7·5 2,220 18 .02 155 63 3C17 271 ~~~-- 35 ·5 .7 .30 1,710 647 __ 42~ 51 --- -- --

Middle Fork Powder River near Kqcee, Wyo. 

Mar 4, 1946 ••••• 464 8.1 506 ...... 0.10 63 12 .33 144 134 13 0.1 3.0 .... 362 2ffl 89 26 

June 2 •••••••••• 354 8.1 505 ...... .10 64 10 50 182 131 16 .1 1.5 .... 396 201 52 .35 

July 19········· 49 8.4 1,010 ...... .10 lll 27 106 d248 .355 .30 .3 1.5 .... 759 388 185 37 

Sept. 10 •••• : ••• 92 8.1 1,230 ...... .10 160 29 94 232 494 II> ·4 2.0 . ... 985 518 .328 28 

Oct. 31 ••••••••• 118 8.3 1,130 ...... .os 110 37 116 a242 l.cfi 38 ·3 1.5 .... 870 427 228 37 

Mar • .30, 1947 ... 169 8.0 972 19 .05 115 39 72 2C17 368 34 ·5 2.3 .28 790 447 277 26 

Ma7 16 •••••••••• '7.30 8.4 502 14 .05 70 19 21 a 157 144 13 ·4 ·4 .18 398 253 124 15 

June 27••••••••• .384 8.2 506 15 .05 62 22 24 155 140 16 ·4 .6 .24 368 245 118 17 

July 15········· 98 8.4 7.37 11 .04 77 34 51 b 185 228 36 ·4 1.4 .18 548 332 180 25 

Aug. 12 ••••••••• 29 7·9 928 12 .05 104 41 72 215 311 59 ·4 .1 .21 760 428 252 27 

l-Iar. 2, 1949 •••• .330 7.7 1,060 13 .04 91 33 87 158 360 31 ·3 2.7 .09 751 362 232 .34 ·~ 31 •••••••••• 2/1> 7·7 7C17 13 .02 74 23 35 164 178 2.3 ·3 1.8 . ... 491 279 145 ·21 

~ 8 •••••••••• 16 8.1 1,250 13 .02 108 42 no 226 .390 62 ·4 ·7 .... 922 M2 257 .35 

Aug. 2•••••••••• .2 7·7 1,630 15 .05 130 49 189 231 520 144 ·4 2.6 .... 1,160 526 .337 44 

Sept. 20•••••••• 39 7·8 891 11 .02 103 .35 49 111> 353 13 .2 1.5 .,30, 682 401 281 21 

Nov. 30••••••••• 100 7.8 1,200 12 .04 120 51 92 244 408 58 ·4 1.9 .... 920 509 .309 28 

Jan. 6, 1950 •••• 100 7.8 1,530 39 .... 144 58 103 280 468 72 ·5 4.0 .... 1,030 598 368 27 

Jan. 31••••••••• 100 7.8 1,.370 14 .... 138 51 102 280 437 62 ·4 4·3 .... 947 554 324 29 

·~· 3·········· 110 7·9 1,260 26 .02 136 44 96 244 433 54 ·4 2.2 .10 974 521 321 29 

Apr. 6 •••••••••• 145 7.6 1,380 14 .02 120 43 131 222 483 51 .6 2.9 .... 955 477 295 37 

~~ 6 ••••••••••• .356 7.6 1,330 18 .04 108 37 133 186 493 28 .6 4·1 .... 914 422 269 41 

June 7 •••••••••• .339 7.8 600 14 .10 60 20 4D 154 154 21 .2 1.7 .... 404 2.32 106 27 

July 6 •••••••••• 38 7.6 1,260 11 .10 110 44 128 221 471 l+J .3 .8 .... 982 456 275 38 

Aug. 2•••••••••• 2.5 7·9 1,570 s.a .06 134 54 141 219 555 73 ·3 ·4 ·35 1,cno 556 .376 .35 

See footnotes at end oi' table, P• 90. ~ 
Table ,3,3.--A.na.:b"ses or water in the Po'Wd.er River drainage basin in Wyoming and Montana-Continued 

.Lina:cytical results in parts per million e:xcept as indicatEg] 

Specific Hardness as DaiJ¥ conduct- Cal- Mag- Po- CaOO) PerDate of mean ance Silica Iron Sodium tas- Bicar- Suli'ate Chlo- Fluo- Ni- Boron Dis- cent 

collection discharge pH (micro- (SiD2) (Fe) cium nesium (Na) sium bonate (S04) ride ride trate (B) solved 1-- so-

(crs) mhos/em (Ca) {Mg) (K) (HCO)) (Cl) (F) (N0,3) solids" Total car- dium 

at 25 C) bonate 

lvJ.id.dle Fork Pol«ier River near Kaycee, Wyo.-Continued 

Sept. s, 1950 ... I 1.7 17·7 I 1,8.3o I 10 I o.02 1149 I 57 I 200 I 210 I 65s l13o I o.4 I o.1 I .... -Jl,.3ior -606 l L.J41 ~ 

Dec. 7, 1949•••• ••......• 7eS 2,290 14 0.02 

Mar. 2, 1950 •••• 13 7.S 1~490 2S .02 

June 6 •••••••••• lJ7 7eS ~ 15 .10 

Jul.;y s .•..••..•. 57 7·4 1,oso 11 .20 

Sept. 2S •••••••• 12 7.9 l,SlO 7.0 .04 

Dec. 7, 1949•••• 5.0 7·5 130 17 .04 

Mar • .3, 1950···· 2 • .3 7·4 w 22 .02 

June 6 •••••••••• .332 6.6 42·0 11 .04 

Sept. S••••••••• 7•S 7.0 ~.9 15 .02 

Dec. 7, 1949•••• S6 s.o 11380 12 .... Mar. 2, 1950 •••• 64 7·4 916 6.4 .02 

June 6 •••••••••• lil7 7.S 494 14 .04 

July s ••••••.•.• .303 7·.3 545 s.6 .02 

Sept. 6 ••••••••• 3·9 7·5 1,820 7·4 .02 

a Includes equivalent or 6 ppm or carbonate (C0,3)• 

b Includes equivalent or 5 ppm or carbonate (co3). 

c Includes equivalent or 10 ppm or carbonate (CO.))• 

d Includes equivalent or 14 ppm or carbonate (C0,3)• 

Craey Woman Creek near Arvada, Wyo. 

224 120 171 3.30 1,oao 

148 75 105 244 66.3 

76 .32 63 148 313 

97 47 8.3 171 445 

162 92 147 216 ~0 

Clear Creek near Buffalo, Wyo. 

16 3·4 10 72 13 

11 1.9 12 62 ,3.0 

6.0 .a .3·7 20 7.0 

9·5 l.S 5·5 45 5·0 

Clear Creek near Arvada, Wyo. 

135 62 113 30S 553 

8.3 44 66 20S 335 

46 19 29 120 147 

46 23 .32 119 170 

157 sa 171 282 S45 

19 0.4 2.2 0.40 1,790 1~050 779 26 

10 .2 ,3.0 .05 1~150 67S 47S . 25 

5·0 ·4 2.0 .20 6,3S .321 200 30 

7.7 .1 1.3 .... 848 L.J6 296 29 

lJ ·3 .a • .3.3 1~400 782 6o5 29 

1.0 .2 1.6 .15 94 54 0 29 

4·0 .1 2.0 .oo sa 36 0 ~ 

1.0 .2 .a • .30 3S 19 3 30 

·5 .1 .2 .20 6S 31 0 2S 

2.6 ·3 6.,3 .20 1,040 592 3.39 29 

5.0 .1 5·5 .... 722 .300 217 27 

1.0 .2 l.S .20 .336 19.3 95 24 

1.0 .1 2.3 .10 366 20S 110 25 

7.0 ·4 5·7 .30 1~~0 754 523 3.3 

co 

0 
DaiJ.T 

mean Source dischaJ:o~e (c.ts 

South Fork Powder River near K~cee, Wyo ••••••••••••••••••• ...... Powder River at Sussex, Wyo ••••• ...... Pm«ier River at Arvada, Wyo ••••• 2.0 

Powier River at Moorhead, Mont •• 54 

Power River near Broadus, Mont. ...... Pow:ler River near Locate, Mont •• 44 

Powder River at mouth, MOnt ••••• ...... Middle Fork Power River near ~~ w)o ••••••••••••••••••• ...... MidcUe Fork Powtler River above 

Ka1oee, Wfo••••••••••••••••••• 40 

Middle Fork Powder River at K~cee,-Wlo••••••••••••••••••• ...... Micklle Fork Powier<River near Ia;rcee, Wfo•••••••··-~--~ •••••••• 12 

Beaver Creek near Barnum, Wyo ••• ...... Red Fork near Barnum, Wyo ••••••• ...... North Fork Powier River near 

MaToworth, ~o•••••••••••••••• lS 

Nort;h Fork Powder River near Ka¥cee, Wyo •••• ~~·•••••••••••• ...... Salt Creek near Sussex, Wyo ••••• ...... North Fork -Crazy Woman Creek 

above -Bil.ly' Creek near Bu.t.talo, Wyo •••••••••••••••••• 9.a 

Nort;h Fork Crazy Woman Creek 

below Middle Fork near Bu!.talo, Wyo •••••••••••••••••• ...... Crazy Woman Creek near Bu.t.talo, 

wyo ••••••••••••••••••••••••••• ...... Middle Fork Crazy Woman Creek at 

Greub, Wyo •• ••• •• ••••••••• •••• 10 

Poison Creek near Greub, Wyo •••• ...... South Fork Cra~ Woman Creek near Greub, WTO••••••••••••••• ...... Clear Creek near Bu.t.talo, Wyo ••• 20 

Clear Creek near Arvada, Wyo •••• 62 

Piney Creek at Kearnq, Wyo ••••• 14 

Lake De Smet, Wyo ••••••••••••••• ...... 

Table 34e--Powder River drainage basin salinity -st'U.dy, Sept. 10 to 14, 1949 

["Analyl:.ical results in parts per-million except a.s indicateg'l 

Specific Sodium 

conduct- (Na) ance Silica Iron Cal- Mag- + Bicar-- Sul.:rate ChlopH (micro- (Si02} (Fe) cium nesium pota.s- bonate (504) ride 

mhos/em (Ca) (Mg) sium (HC03) (Cl) 

at 25 C} (K) 

7.4 -2,640 15 o.o6 22a 55 329 l;a 1,020 21S 

7·5 2,460 10 .06 22a 77 256 l9S 960 195 

7.6 3,100 4·4 .02 236 99 369 l.S2 1,360 162 

7.7 1,500 5.2 .02 126 84 115 262 656 6.4 

7·7 1,630 7.2 .02 124 so 147 244 7l2 10 

7.4 2,010 10 .02 JJS 79 220 244 880 20 

7.5 2,140 9.6 .02 154 7l 261 240 968 25 

a.; 293 10 .16 32 17 1.a al72 ;.6 4·0 

7·9 1,030 10 .10 121 40 55 204 384 J3 

7e7 1,450 ll .06 128 53 127 2o6 504 84 

7·7 1,520 a.o ·04 135 53 148 222 560 79 

a.o 1,160 17 .12 125 59 58 236 460 3·5 

a.2 643 9.a .12 59 29 35 b22a ll4 25 

a.2 909 15 .10 83 40 63 c 264 2SS 1.5 

7·4 2,080 ll e04 156 S6 253 282 984 26 

7.a 4,UO 7.6 .10 25a lJ3 792 292 2,280 152 

7·7 252 15 ·14 26 a.9 12 100 40 1.0 

7·9 1,130 l3 ·14 95 56 67 222 ~ 4·5 

7·9 1,770 6.a .04 152 100 140 216 860 14 

S.1 492 J.6 .10 6.3 19 9.0 170 lOS 1.o· 

7.a 3,710 15 .16 466 w 334 256 2,140 25 

a.l 1,220 l4 .12 9a 60 lOS 294 452 .3·5 

7·4 66.0 12 .06 10 1.0 .; 32 3a2 ·4 

7eS 1,620 6.2 .02 1.32 89 ll2 234 704 s.o 

7.6 200 ll .02 2S 7e0 .9 104 l4 1.2 

a.o 1,020 10 .10 5.3 44 ll3 200 368 7.a 

See .footnotes at end or table, P• 92. 

Fluo- Ni- Disride trate solved 

(F) (N03) solids 

1.a 7.2 1,950 

1.0 2.0 1,830 

1.2 2.6 2,330 

.a 3·3 1,130 .a 2.0 1,210 

1.2 1.4 1,470 

1.2 1.4 1,610 

.1 ·7 l5a 

.2 1.3 754 

·4 .o 11 010 

·4 .o 1,090 

.2 4el 89a 

.2 .a 394 

.2 ·3 63a 

·4 ·5 1,660 

1.0 .o 3,750 

.2 ·9 158 

.2 1.9 822 

.6 .2 1,.380 

.2 ·7 .318 

.6 ·7 .3,250 

.2 1.6 906 

.o .2 46 .a 7.2 1,170 .o .2 126 

.2 l.a Sl.6 

Hardness as CaCO) 

NonTotal carbonate 

795 665 

SS6 '724 

996 847 

660 445 

639 439 

670 470 

677 ~ 

150 9 

467 300 

53 a 369 

555 31.3 

555 361 

267 80 

372 156 

743 512 

l,llO S7l 

102 lS 

46a 286 

791 614 

235 96 

16750 1,540 

491 250 

29 .3 

696 504 

99 14 

314 150 

Percent 

sodium 

47 

39 

45 

2a 

33 

42 

46 

3 

2l 

34 

37 

19 

22 

27 

43 

61. 

20 

24 

2S 

a 

29 

32 

.3 

26 

2 

1.4 

co 

..... 
Table .34.--Pot.der River drainage basin salinity study, Sept. 10 to 14, 1949-Continued 

["Ana.J.ytical results in parts per million except as indicates? 

Dai:cy' Specific 

conduct- mean ance Source dis- pH (micro- char~e 

(c.fs mhos/em 

at 25 C) 

Little Powder River near 

Broadus, Y~nt••••••••••••••••• 2.4 7·4 2,690 

Yellowstone River above con- .fluence with Power River, 

MOnt•••••••••••••••••••••••••• ...... 7·5 867 

Yellowstone River at Terr.y, 

MOnt•••••••••••••••••••••••••• ...... 7·5 ·~-

a Includes equivalent of 12 ppm Qf carbonate (C~). 

b Includes equivalent of 8 ppm of ~bonate (C0.3/• c Includes equivalent of 6 ppm of carbonate ( C0.3). 

~ 

~ 

~ 

~ 11:1 

i 

... 

~ 

., 

... 

Silica Iron 

(Si02) (Fe) 

6.2 0.02 

12 .o2 

L_~- .02 

Sodium 

(Na) Cal- Mag- + Bicar- Sul.rate Chlo- Fluocium nesium potas- bonate (S04) ride ride 

(Ca) (Mg) (HC0.3) (Cl)~ (F) sium 

(K) 

1.37 77 400 .329 1,210 9.6 1.0 

66 26 ao 196 252 11 1.4 

67 28 77 200 256 10 .8 

Ni- Distrate solved 

(N0.3) solids 

2.0 2,020 

4o0 610 

.3·4 616 

Hardness as 

CaC0.3 

NonTotal carbonate 

659 .3S9 

272 lll 

282 118 

Percent 

sodium 

57 

.39\ 

.37 

~ 

ro