Prepared in cooperation with the

NATIONAL PARK SERVICE U.S. DEPARTMENT OF THE INTERIOR

U.S. GEOLOGICAL SURVEY

Suspended-Sediment Concentration and

Pool Sedimentation Data for the Gibbon River, 

Yellowstone National Park, Wyoming,

September 2000 through October 2001

Open-File Report 03-185
 i

U.S. Department of the Interior

U.S. Geological Survey

Suspended-Sediment Concentration and Pool 

Sedimentation Data for the Gibbon River, Yellowstone 

National Park, Wyoming, September 2000 through 

October 2001

By Peter R. Wright and Ronald B. Zelt

Open-File Report 03-185 

Prepared in cooperation with the

NATIONAL PARK SERVICE

Cheyenne, Wyoming

2003
ii SEDIMENTATION DATA FOR THE GIBBON RIVER, YELLOWSTONE NATIONAL PARK 

U.S. Department of the Interior

GALE A. NORTON, Secretary

U.S. Geological Survey

Charles G. Groat, Director

Any use of trade, product, or firm names in this publication is for 

descriptive purposes only and does not imply endorsement by the 

U.S. Government

For additional information write to:

District Chief

U.S. Geological Survey, WRD

2617 E. Lincolnway, Suite B

Cheyenne, Wyoming 82001

Copies of this report can be purchased from:

U.S. Geological Survey

Branch of Information Services

Box 25286, Denver Federal Center

Denver, Colorado 80225
CONTENTS iii

CONTENTS

Page

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

Introduction........................................................................................................................................................................... 1

Purpose and scope....................................................................................................................................................... 3

Description of area ...................................................................................................................................................... 3

Methods................................................................................................................................................................................. 3

Streamflow .................................................................................................................................................................. 3

Suspended sediment.................................................................................................................................................... 3

Geomorphology of pools ............................................................................................................................................ 4

References............................................................................................................................................................................. 5

Data tables............................................................................................................................................................................. 7

Figures

1. Location of streamflow-gaging stations, sediment-measurement sites, and pool study reach points along 

the Gibbon River, Yellowstone National Park, Wyoming................................................................................. 2

Tables

1. Daily mean streamflow data for station 06037100, Gibbon River at Grand Loop Road Bridge at Madison 

Junction, Yellowstone National Park, Wyoming, March 23 through September 30, 2001............................... 9

2. Streamflow measurements and width- and depth-integrated suspended-sediment data for the Gibbon River, 

September 14, 2000 through October 11, 2001 ................................................................................................ 10

3. Suspended-sediment data for automatic-pumped samples collected at station 06036950, Gibbon River 

below Canyon Creek, near West Yellowstone, Montana, March 22 through June 28, 2001 ............................ 11

4. Suspended-sediment data for automatic-pumped samples collected at station 06037100, Gibbon River at 

Grand Loop Road Bridge at Madison Junction, Yellowstone National Park, Wyoming, 

April 7 through June 28, 2001 .......................................................................................................................... 12

5. Daily mean suspended-sediment concentrations and loads for station 06037100, Gibbon River at Grand 

Loop Road Bridge, at Madison Junction, Yellowstone National Park, Wyoming, April 1 through 

June 30, 2001 .................................................................................................................................................... 13

6. Summary of pool geometry measurements in the Gibbon River, October 2000..................................................... 14

7. Particle-size distribution of fine bed sediment in pools, Gibbon River, October 2000 ........................................... 15

8. Particle-size distribution of surficial bed material in a riffle, Gibbon River, October 2000 .................................... 16
iv SEDIMENTATION DATA FOR THE GIBBON RIVER, YELLOWSTONE NATIONAL PARK 

CONVERSION FACTORS, DATUMS AND ABBREVIATIONS

Multiply By To obtain

Length

foot (ft) 0.3048 meter (m)

inch (in) 2.54 centimeter (cm)

inch (in) 25.40 millimeter (mm)

mile (mile) 1.609 kilometer (km)

Area

square mile (mi2) 2.590 square kilometer (km2)

Load

ton per day (ton/d) 907.2 kilogram per day

Temperature can be converted to degrees Fahrenheit (oF) or degrees Celcius (oC) as follows:

oF = 9/5 (oC) + 32

oC = 5/9 (oF-32)

In this report, vertical coordinate information is referenced to the National Geodetic Vertical Datum of 1929 (NGVD of 1929); horizontal 

coordinate information is referenced to the North American Datum of 1927 (NAD 27).

Abbreviations used in this report:

cm centimeter

ft3/s cubic foot per second

GCLAS Graphical constituent loading analysis system

m meter

m2 square meter

m3 cubic meter

m3/s cubic meter per second

mg/L milligrams per liter

mm millimeter

μm micrometer

USGS U.S. Geological Survey

YNP Yellowstone National Park
ABSTRACT 1

ABSTRACT

This report presents data on streamflow, suspended-sediment concentration, geomorphic measurements of pools, and particle-size distribution 

of surficial bed material, collected along a 

5-mile reach of the Gibbon River in Yellowstone 

National Park. The study was done in cooperation 

with the National Park Service. The Park Service 

was concerned about the potential effects that road 

reconstruction would have on water quality.

A streamflow-gaging station and two automatic pumping samplers were installed in September 2000 to collect suspended-sediment samples. 

The gage and samplers were operated seasonally 

from March through September 2001. The geomorphic survey of pools and sampling of bed 

material occurred during October 2000. 

INTRODUCTION

The Gibbon River in Yellowstone National Park 

(YNP) (fig. 1) is an important trout fishery, featuring 

geothermally affected water in which fish and invertebrates are buffered against extremely low temperatures 

and ice formations (Varley and Schullery, 1983). In 

1997, the Gibbon River ranked sixth in popularity 

among 73 streams and lakes fished in YNP (National 

Park Service, 1999). Several events in the Gibbon 

watershed since 1988 have individual or cumulative 

potential to increase sediment yields. The Gibbon 

River drainage was severely burned in the Greater Yellowstone fires of 1988 (Greater Yellowstone Coordinating Committee, 1989). Subsequent rain runoff 

produced debris flows that deposited large volumes of 

sediment and rock along and within the channel of the 

Gibbon River during 1989-91 (Meyer, 1993). Lastly, 

reconstruction and partial re-routing of the paved Park 

Service road along the Gibbon River commenced in the 

spring of 2001, which could represent a source of 

potential sediment erosion. Road reconstruction is 

planned to be completed in several phases over the following 4 to 6 years (National Park Service, 1999).

Deposition of fine sediment on the streambed can 

cause decreased survival of salmonid eggs and alevins 

by restricting flow and dissolved-oxygen distribution 

through streambed gravel, resulting in suffocation. 

Filling of pools with fine sediment deposits can reduce 

available habitat for benthic invertebrate communities 

that live on the surfaces of coarse substrate. Sedimentcaused turbidity decreases light penetration, which 

may inhibit primary production and disrupt food-chain 

energy transfer. Finally, increased turbidity adversely 

affects aesthetic values of streams, an important consideration for high-profile streams such as those in 

YNP.

Concerns about the potential effects that road 

reconstruction would have on water quality prompted 

the National Park Service and the U.S. Geological Survey (USGS) to enter into an agreement to characterize 

sediment conditions in the Gibbon River. The study 

was designed to: (1) document the mean daily 

suspended-sediment concentrations, fine bed-sediment 

size distribution in pools, and degree of pool sedimentation of the Gibbon River prior to the road reconstruction activity, (2) monitor conditions during the 

reconstruction period, and (3) compare the postconstruction conditions with the pre-construction baseline to evaluate any substantial changes.

Suspended-Sediment Concentration and Pool 

Sedimentation Data for the Gibbon River, 

Yellowstone National Park, Wyoming, September 

2000 through October 2001

By Peter R. Wright and Ronald B. Zelt
INTRODUCTION 2

Figure 1. Location of streamflow-gaging stations, sediment-measurement sites, and pool study reach points along the Gibbon RiveYellowstone National Park, Wyoming.
METHODS 3

Purpose and Scope

The purpose of this report is to present the data 

collected during the first two seasons of this study 

(September 2000 through October 2001). Streamflow 

and suspended-sediment data are published here and as 

part of the Wyoming Water Resources Data Report for 

the 2001 water year (Swanson and others, 2002). Other 

data in this report include the geomorphic survey data 

for 16 pools, along with particle-size data for 18 samples of fine bed-sediment in pools. Methods of data 

collection and quality-assurance data are included in 

this report.

Description of Area

The Gibbon River originates at Grebe Lake at an 

elevation of 8023 ft (feet) above NGVD of 1929 and 

flows 29 miles southwesterly to join the Firehole River 

at an elevation of 6798 ft. The upper river drains a 

high, mountainous area with small tributaries fed by 

snowmelt and cold springs. Middle reaches of the river 

receive tributary flows fed by snowmelt and cold 

springs (such as Solfatara Creek, Canyon Creek, and 

Secret Valley Creek), and effluent from geyser basins 

(Norris, Gibbon, and Monument) and hot springs (such 

as Sylvan, Beryl, and Iron). Soils are sandy, originating 

chiefly from glacial till or colluvium (National Park 

Service, 1999). Streambed materials are primarily volcanic rhyolite, with gravel constituting the largest size 

fraction (Vincent, 1967). 

The snowmelt runoff period typically begins in 

mid-April, peaks by mid-June, and then declines rapidly until mid-July. During the remainder of the year, 

flows generally are low and relatively constant, 

although heavy rains and ensuing runoff events are not 

uncommon. The geyser and hot spring effluent contribute about 2 percent of total flow of the river during the 

snowmelt runoff period, and about 6 percent during 

low-flow conditions (Vincent, 1967). During the period 

from March 23, 2001 to October 11, 2001, the Gibbon 

River at Grand Loop Road Bridge had a maximum 

daily mean flow of 584 ft3

/s (cubic feet per second) on 

May 16 and a minimum daily mean flow of 79 ft3/s on 

September 4. Daily mean sediment loads during this 

same period reached a maximum daily load of 596 

tons/d (tons per day) on May 16 and a minimum daily 

load of 0.77 tons/d on June 27.

METHODS

The studied segment of the Gibbon River was 

based upon the area of road reconstruction. The study 

segment extends from the Gibbon Falls picnic area 

downstream to the Grand Loop Road Bridge at Madison Junction—a distance of about 5 mi. At the upper 

end of the study segment, which starts just below the 

mouth of Canyon Creek, a portable automatic waterquality sampler was installed. At the lower end of the 

study segment, a streamflow-gaging station and a portable automatic water-quality sampler were installed on 

the downstream side of the Grand Loop Road Bridge at 

Madison Junction (station 06037100). Within the 

study segment, 7 reaches were delineated for geomorphic pool surveys and 16 individual pool areas were 

identified for data collection.

Streamflow

Streamflow-gaging station 06037100 was installed 

in September 2000 and activated on March 20, 2001. It 

was operated until it was closed down for the coldweather season on October 11, 2001. Levels were surveyed to establish a datum for which relative gage 

heights could be reported. Streamflow was measured 

periodically to establish a stage-flow rating, and daily 

mean streamflow records were computed in accordance 

with standard USGS methods (Rantz and others, 1982). 

Daily streamflow records for the seasonal period of 

gage operation are presented in table 1 at the back of 

this report. Streamflow measurements are listed in table 

2 at the back of this report.

Suspended Sediment 

Two automatic pumping samplers were installed 

in the Gibbon River in September 2000. Each of these 

samplers, one just below the inflow of Canyon Creek 

(station 06036950) and the other at Madison Junction 

(station 06037100), were used to collect water samples 

that were analyzed for suspended-sediment concentration. The sampler immediately below the confluence 

of Canyon Creek was installed to attempt to detect possible effects of sediment inputs from debris torrents or 

erosion of debris fans that are not associated with road 

reconstruction. 
METHODS 4

Both automatic samplers were operated using the 

same sampling frequency. The samplers were programmed to collect once-daily samples from March 22 

through June 28, 2001. A subset of these samples representing every other day from April 13 through May 

5, 2001 was sent for analysis. Samples for May 6 

through May 13, 2001 were lost in transit. All daily 

samples for May 14 through June 28, 2001 were sent 

for analysis.

After the snowmelt runoff period had ended in 

June, the samplers were reprogrammed to collect storm 

runoff “event” samples. An “event” was defined as any 

flow magnitude within the upper 10 percent of the flowduration curve. The Gibbon River did not have any 

events large enough to reach the upper 10 percent of the 

duration curve so no “event” samples were collected.

Automatic samplers are efficient tools for the collection of water samples in remote areas or during 

short-duration events. However, these samples do not 

represent the “true” mean suspended-sediment concentration of the stream at the time of collection, because 

the sample is pumped from a single point in the cross 

section (Edwards and Glysson, 1999). To determine 

the “true” mean, a relation needs to be determined by 

comparing automatic point samples with depthintegrated, cross-sectional samples over the full range 

of flow (Edwards and Glysson, 1999). Depthintegrated, equal-width increment, cross-sectional 

samples (table 2) were collected concurrently with corresponding automatic point samples. Cross-sectional 

samples were collected in accordance with standard 

USGS protocols described by Edwards and Glysson 

(1999). These protocols are designed to provide 

discharge-weighted composite samples that best represent the mean suspended-sediment concentration 

across the entire cross section.

All samples submitted to the laboratory were analyzed for suspended-sediment concentration, and 

approximately 30 percent of those samples were analyzed for sand-silt distribution (percent less than 

0.062-mm (millimter) diameter). Suspended-sediment 

concentration and particle-size distribution data for 

point samples collected at station 06036950 are presented in table 3, and for station 06037100 are presented in table 4. Samples were analyzed by the USGS 

sediment laboratory in Helena, Montana, in accordance 

with methods described in Guy (1969) and Lambing 

and Dodge (1993). 

To determine the daily suspended-sediment load 

(suspended-sediment mass discharged over a 24-hour 

period), daily suspended-sediment concentrations from 

automatic samples and streamflow data were utilized 

with data from depth-integrated cross-sectional samples using the computer program “Graphical Constituent Loading Analysis System” (GCLAS) of the USGS 

(McKallip and others, 2001). Mean-daily suspendedsediment concentration and load data, calculated using 

GCLAS, are presented in table 5 for station 06037100.

Geomorphology of Pools

Seven reaches of the Gibbon River distributed 

about evenly along the study segment between 

sediment-measurement sites (fig. 1) were selected for 

targeted geomorphic sampling. These reaches provided a suitable set of pools for monitoring finesediment deposition during low flow. The study 

reaches have gradients and pool spacing typical of 

pool-riffle or plane-bed channel types (Montgomery 

and Buffington, 1993). For the purposes of this study, 

pools were defined at low flow as areas of the channel 

with reduced velocity, little surface turbulence, deeper 

water than surrounding areas (Fitzpatrick and others, 

1998), a distinct downstream terminus (“riffle crest”), 

and containing the channel thalweg (Lisle and Hilton, 

1992). The residual pool is defined as the portion of the 

pool that is deeper than the hydraulic control (riffle 

crest) at the downstream end of the pool. In other 

words, the residual pool is the portion of the pool that 

would remain filled with water when the stream is 

barely flowing. 

Within these 7 reaches, a total of 16 pools were 

measured and sampled in October 2000 using methods 

described by Hilton and Lisle (1993). Data were collected and used to determine the proportion of residual 

pool volume filled by fine sediment (Lisle and Hilton, 

1992, 1999) during low flow. The fraction of residual 

pool volume filled with fine sediment (V*) is the ratio 

of fine-sediment volume (Vrf) to the combined pool 

water and fine-sediment volume (Vr) (Lisle and Hilton, 

1992, 1999). 

The calculation of V* requires measurements of 

the water and fine-sediment volumes within the “residual” part of each pool. The first step in measuring each 

pool was to measure the riffle-crest depth. This was 

measured as the mean of several soundings in the thal-
METHODS 5

weg at the downstream terminus of each pool. The riffle crest depth was then used to physically determine 

the residual pool boundaries. For example, if a pool 

had a riffle crest depth of 10 cm (centimeters) then the 

residual pool boundary would be all areas of the pool 

that have a combined water/fine-sediment depth of 

10 cm or greater. 

Reach length and position of each pool relative to 

a reference station (reach point 0) were measured 

approximately along the stream centerline. Eleven to 

25 soundings were made along a minimum of four 

transects across each pool, using a graduated steel rod 

0.95 cm (0.375 in. (inch)) in diameter. Abrupt changes 

in resistance to penetration of the rod as it passed from 

sand or fine gravel to packed coarse gravel and cobbles 

indicated the base of the fine-sediment deposit. 

Table 6 lists the results of the various geomorphic 

measurements of the 16 pools in the study segment. On 

the basis of these measurements, the volume-weighted 

mean proportion (V*w) of the residual pool volumes 

filled with fine sediment was 14.9 percent. 

From each of the measured pools, bed-material 

samples of the fine sediment overlying the gravel 

framework were collected. These samples were analyzed by Inberg-Miller Engineers in Cheyenne, Wyoming, to determine the size distribution of the fine bed 

sediments filling each pool. The results of these analyses are listed in table 7. 

Samples of the fine bed sediments were collected 

using a 52-mm (2-in.) diameter pipe dredge with an 

attached sampling bag. The dredge sampler was used to 

collect a bulk composite sample of the residual pool 

fines from a minimum of three different sampling 

points in each pool. Two replicate samples of bed material were collected and analyzed for quality control. 

Surficial bed material was sampled in one riffle as 

part of this study. This was accomplished using a pebble count (Wolman, 1954) of at least 100 particles 

along a tape or transverse line using dmax spacing (that 

is, the largest clast expected along the transect; see 

Bunte and Abt, 2001, p. 146-147). The intermediatediameter size class of each clast was measured using a 

US SA-97 hand-held particle-size analyzer (template). 

The particle-size distribution of the sampled riffle is 

listed in table 8. The degree to which sampled particles 

larger than 6 mm were embedded in fine sediment was 

visually estimated for one-half of those sampled particles (every second particle selected). Embeddedness 

data also are listed in table 8.

REFERENCES

Bunte, K. [I.], and Abt, S.R., 2001, Sampling surface and 

subsurface particle-size distributions in wadable graveland cobble-bed streams for analyses in sediment transport, hydraulics, and streambed monitoring: U.S. 

Department of Agriculture, Forest Service General 

Technical Report RMRS-GTR-74, 428 p.

Edwards, T.K., and Glysson, G.D., 1999, Field methods for 

measurement of fluvial sediment: U.S. Geological Survey Techniques of Water-Resources Investigations, 

book 3, chap. C2, 89 p.

Fitzpatrick, F.A., Waite, I.R., D'Arconte, P.J., Meador, M.R., 

Maupin, M.A., and Gurtz, M.E., 1998, Revised methods for characterizing stream habitat in the National 

Water-Quality Assessment Program: U.S. Geological 

Survey Water-Resources Investigations Report 98-

4052, 67 p.

Greater Yellowstone Coordinating Committee, 1989, The 

Greater Yellowstone postfire assessment: Greater Yellowstone Coordinating Committee, Postfire Assessment Committee, 147 p.

Guy, H.P., 1969, Laboratory theory and methods for sediment analysis: U.S. Geological Survey Techniques of 

Water-Resources Investigations, book 5, chap. C1, 58 p. 

Hilton, Sue, and Lisle, T.E., 1993, Measuring the fraction of 

pool volume filled with fine sediment: Albany, Calif., 

U.S. Forest Service Pacific Southwest Research Station 

Research Note PSW-RN-414, 11 p.

Lambing, J.H., and Dodge, K.A., 1993, Quality assurance 

for laboratory analysis of suspended-sediment samples 

by the U.S. Geological Survey in Montana: U.S. Geological Survey Open-File Report 93-131, 34 p.

Lisle, T.E., and Hilton, Sue, 1992, The volume of fine sediment in pools—An index of sediment supply in gravelbed streams: Water Resources Bulletin, v. 28, no. 2, p. 

371-383.

______1999, Fine bed material in pools of natural gravel bed 

channels: Water Resources Research, v. 35, p. 1291-

1304.

McKallip, T.E., Koltun, G.F., Gray, J.R., and Glysson, G.D., 

2001, GCLAS - A Graphical Constituent Loading 

Analysis System, in Proceedings of the Seventh Federal 

Interagency Sedimentation Conference, Reno, Nevada, 

March 25-29: Subcommittee on Sedimentation, v. II, p. 

VI-49 to VI-52.
6 SEDIMENTATION DATA FOR THE GIBBON RIVER, YELLOWSTONE NATIONAL PARK 

Meyer, G.A., 1993, Holocene and modern geomorphic 

response to forest fires and climate change in Yellowstone National Park: Albuquerque, University of New 

Mexico, unpublished Ph.D. dissertation, 402 p.

Montgomery, D.R., and Buffington, J.M., 1993, Channel 

classification, prediction of channel response, and 

assessment of channel condition: Washington State 

Timber/Fish/Wildlife Agreement, Report TFW-SH10-

93-002, 84 p.

National Park Service, 1999, Environmental assessment—

Madison Junction/Norris Junction road improvement, 

Yellowstone National Park: Denver, Colo., National 

Park Service, 84 p.

Rantz, S.E., and others, 1982, Computation of discharge: 

U.S. Geological Survey Water-Supply Paper 2175, 2 v., 

631 p.

Swanson, R.B., Woodruff, R.E., Laidlaw, G.A., Watson, 

K.R., and Clark, M.L., 2002, Water resources data, 

Wyoming, water year 2001; Volume 1. Surface water: 

U.S. Geological Survey Water-Data Report WY-01-1, 

518 p. Online (downloadable pdf file) at http://

wy.water.usgs.gov/pubs/adr/index.htm#Water Year 

2001.

Varley, J.D., and Schullery, P., 1983, Freshwater wilderness, 

Yellowstone fishes and their world: Yellowstone 

Library and Museum Association, Yellowstone 

National Park, 132 p.

Vincent, E.R., 1967, A comparison of riffle insect populations in the Gibbon River above and below the geyser 

basins, Yellowstone National Park: Limnology and 

Oceanography, v. 12, p. 18-26.

Wolman, M.G., 1954, A method of sampling coarse river bed 

material: AmericanGeophysical Union Trnsactions, v. 

35, no. 6, p. 951-956.
 7

DATA TABLES
DATA TABLES 9

Table 1. Daily mean streamflow data for station 06037100, Gibbon River at Grand Loop Road Bridge at Madison Junction, 

Yellowstone National Park, Wyoming, March 23 through September 30, 2001

[MAX, maximum; MIN, minimum; AC-FT, acre-feet; --, no data]

LOCATION.--Latitude 44°38'26", longitude 110°51'40", Teton County, Hydrologic Unit 10020007, Yellowstone National Park, on right bank, downstream 

side of bridge on highway 191-287, 0.2 miles upstream from the confluence with the Firehole River, 0.3 miles south of Madison Junction, and 14 miles east 

of West Yellowstone, Mont.

DRAINAGE AREA.--126 square miles.

GAGE.--Water-stage recorder. Elevation of gage is 6,800 ft above NGVD of 1929, from topographic map.

REMARKS.--Records fair. No regulation or diversions upstream from station. Streamflow measurement made on Oct. 12 during period station was not in 

operation was 138 cubic feet per second.

DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001

DAILY MEAN VALUES

DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP

1 -- -- -- -- -- -- 103 261 159 112 93 84

2 -- -- -- -- -- -- 107 213 153 109 90 82

3 -- -- -- -- -- -- 103 189 154 108 88 81

4 -- -- -- -- -- -- 104 189 160 108 90 79

5 -- -- -- -- -- -- 103 210 155 111 89 84

6 -- -- -- -- -- -- 105 220 160 110 86 87

7 -- -- -- -- -- -- 105 210 148 111 87 86

8 -- -- -- -- -- -- 109 225 143 117 88 85

9 -- -- -- -- -- -- 102 260 139 122 88 82

10 -- -- -- -- -- -- 100 257 133 139 87 81

11 -- -- -- -- -- -- 98 249 128 124 87 80

12 -- -- -- -- -- -- 100 254 141 118 87 81

13 -- -- -- -- -- -- 101 264 153 113 88 84

14 -- -- -- -- -- -- 99 262 166 114 95 86

15 -- -- -- -- -- -- 92 326 182 118 97 86

16 -- -- -- -- -- -- 94 584 145 121 92 85

17 -- -- -- -- -- -- 101 425 131 114 92 86

18 -- -- -- -- -- -- 121 323 129 109 90 84

19 -- -- -- -- -- -- 143 276 127 107 88 84

20 -- -- -- -- -- -- 142 248 125 105 87 83

21 -- -- -- -- -- -- 140 228 122 103 88 81

22 -- -- -- -- -- -- 131 214 120 102 88 81

23 -- -- -- -- -- 99 127 202 119 101 87 81

24 -- -- -- -- -- 102 125 190 117 99 85 80

25 -- -- -- -- -- 104 144 183 116 98 85 80

26 -- -- -- -- -- 103 165 190 116 97 84 81

27 -- -- -- -- -- 102 201 180 116 96 83 81

28 -- -- -- -- -- 103 227 201 114 96 83 81

29 -- -- -- -- -- 104 259 236 114 94 83 82

30 -- -- -- -- -- 106 235 179 113 95 82 81

31 -- -- -- -- -- 99 -- 165 -- 93 83 --

TOTAL -- -- -- -- -- 922 3,886 7,613 4,098 3,364 2,720 2,479

MEAN -- -- -- -- -- 102 130 246 137 109 87.7 82.6

MAX -- -- -- -- -- 106 259 584 182 139 97 87

MIN -- -- -- -- -- 99 92 165 113 93 82 79

AC-FT -- -- -- -- -- 1,830 7,710 15,100 8,130 6,670 5,400 4,920
10 SEDIMENTATION DATA FOR THE GIBBON RIVER, YELLOWSTONE NATIONAL PARK 

Table 2. Streamflow measurements and width- and depth-integrated suspended-sediment data for the Gibbon River, 

September 14, 2000 through October 11, 2001

[ft, feet; ft3/sec, cubic feet per second; Conc., suspended-sediment concentration; mg/L, milligrams per liter; mm, millimeter; --, no data]

Date Time

Streamflow, 

instantaneous 

(ft3/sec)

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm Time

Gage 

height 

(ft)

Streamflow, 

instantaneous 

(ft3/sec)

Conc. 

(mg/L)

Percent 

finer than

0.062 mm

06036950 - Gibbon River below Canyon Creek near West 

Yellowstone, Montana

06037100 - Gibbon River at Grand Loop Road at Bridge Madison 

Junction, Yellowstone National Park, Wyoming

09-14-00 1225 85 5 -- 1445 4.09 105 4 --

09-27-00 1600 85 9 90 1700 4.10 100 21 54

10-12-00 -- -- -- -- 1030 4.18 138 6, 15

1

Replicate sample.

--

10-15-00 1500 96 3, 13 -- -- -- -- -- --

03-22-01 1730 89 10 -- 1500 4.06 107 10 --

05-14-01 2002 -- 16 83 1602 4.69 274 28 77

05-14-01 2004 -- 17 79 1604 4.69 274 21 80

05-14-01 2006 -- 17 79 1606 4.69 274 30 50

05-18-01 1002 324 23 67 0902 4.95 331 33 80

05-18-01 1004 324 19 72 0904 4.95 331 23 75

05-18-01 1006 324 21 70 0906 4.95 331 30 51

06-05-01 1302 154 5 93 1102 4.28 149 6 87

06-05-01 1304 154 5 85 1104 4.28 149 6 88

06-05-01 1306 154 4 62 1106 4.28 149 5 78

06-28-01 1600 94 -- -- 1400 4.11 110 -- --

08-13-01 -- -- -- -- 1530 4.01 86 -- --

10-11-01 1301 69 26 57 1001 4.00 88 12 58

10-11-01 1302 69 4 -- 1002 4.00 88 2 --

10-11-01 21303

2

Samples lost in transit.

-- -- -- 1003 4.00 88 2 80

10-11-01 1304 69 4 -- 1004 4.00 88 2 --

10-11-01 21305 -- -- -- 1005 4.00 88 -- 78

10-11-01 1306 69 5 -- 1006 4.00 88 -- --

10-11-01 1307 69 2 91 1007 4.00 88 -- 78
DATA TABLES 11

Table 3. Suspended-sediment data for automatic-pumped samples collected at station 06036950, Gibbon River below 

Canyon Creek, near West Yellowstone, Montana, March 22 through June 28, 2001

[These data represent suspended-sediment concentrations of instantaneous point samples collected using an automatic pumping sampler. Conc., 

concentration; mg/L, milligrams per liter; mm, millimeter; --, no data]

Day Time

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm Time

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm Time

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm Time

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm

March April May June

1 -- -- -- 1900 11 -- 1900 126 -- 1200 28 --

2 -- -- -- -- -- -- -- -- 1200 19 85

3 -- -- -- 1900 14 -- 1900 141 -- 1200 32 --

4 -- -- -- -- -- -- -- -- 1200 18 --

5 -- -- -- 1900 13 70 1900 36 75 1200 14 48

6 -- -- -- -- -- -- -- -- -- 1200 11 --

7 -- -- -- 1900 9 -- -- -- -- 1200 11 81

8 -- -- -- -- -- -- -- -- -- 1200 14 --

9 -- -- -- 1900 13 -- -- -- -- 1200 11 --

10 -- -- -- -- -- -- -- -- -- 1200 13 72

11 -- -- -- 1900 13 80 -- -- -- 1200 15 --

12 -- -- -- -- -- -- -- -- -- 1200 13 --

13 -- -- -- 1900 18 -- -- -- -- 1200 7 91

14 -- -- -- -- -- -- 2000 1922 -- 1200 19 --

15 -- -- -- 1900 17 -- 2000 1115 5 1200 31 --

16 -- -- -- -- -- 2000 733 -- 1200 13 82

17 -- -- -- 1900 66 87 2000 183 -- 1200 11 --

18 -- -- -- -- -- -- 2000 60 -- 1200 9 --

19 -- -- -- 1900 27 -- 1200 38 -- 1200 10 70

20 -- -- -- -- -- -- 1200 38 -- 1200 12 --

21 -- -- -- 1900 29 -- 1200 25 70 1200 12 --

22 1900 11 -- -- -- -- 1200 37 -- 1200 10 75

23 -- -- -- 1900 29 86 1200 35 -- 1200 12 --

24 1900 13 79 -- -- -- 1200 23 70 1200 13 --

25 -- -- -- 1900 102 -- 1200 25 -- 1200 13 55

26 1900 13 -- -- -- -- 1200 26 -- 1200 9 --

27 -- -- -- 1900 201 -- 1200 24 62 1200 17 --

28 1900 13 -- -- -- -- 1200 50 -- 1200 17 40

29 -- -- -- 1900 117 67 1200 76 -- -- -- --

30 1900 12 88 -- -- -- 1200 28 64 -- -- --

31 -- -- -- -- -- -- 1200 26 -- -- -- --
12 SEDIMENTATION DATA FOR THE GIBBON RIVER, YELLOWSTONE NATIONAL PARK 

Table 4. Suspended-sediment data for automatic-pumped samples collected at station 06037100, Gibbon River at Grand 

Loop Road Bridge at Madison Junction, Yellowstone National Park, Wyoming, April 7 through June 28, 2001

[These data represent suspended-sediment concentrations of instantaneous point samples collected using an automatic pumping sampler. Conc., 

concentration; mg/L, milligrams per liter; mm, millimeter; --, no data]

Day Time

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm Time

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm Time

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm Time

Conc. 

(mg/L)

Percent 

finer than 

0.062 mm

March April May June

1 -- -- -- -- -- -- 1900 37 -- 1200 17 42

2 -- -- -- -- -- -- -- -- 1200 18 --

3 -- -- -- -- -- -- 1900 20 -- 1200 17 --

4 -- -- -- -- -- -- -- -- 1200 14 49

5 -- -- -- -- -- -- 1900 23 82 -- -- --

6 -- -- -- -- -- -- -- -- -- 1200 11 --

7 -- -- -- 1900 22 -- -- -- -- 1200 14 51

8 -- -- -- -- -- -- -- -- -- 1200 11 --

9 -- -- -- -- -- -- -- -- -- 1200 21 --

10 -- -- -- -- -- -- -- -- -- 1200 7 90

11 -- -- -- -- -- -- -- -- -- 1200 10 --

12 -- -- -- -- -- -- -- -- -- 1200 9 --

13 -- -- -- 1900 14 -- -- -- -- 1200 9 81

14 -- -- -- -- -- -- 1900 21 -- 1200 12 --

15 -- -- -- 1900 10 62 1900 83 81 1200 23 --

16 -- -- -- -- -- 1900 1359 -- 1200 11 88

17 -- -- -- -- -- -- 1900 3510 -- 1200 10 --

18 -- -- -- -- -- -- 1200 141 -- 1200 8 --

19 -- -- -- 1900 18 -- 1200 53 -- 1200 6 96

20 -- -- -- -- -- -- 1200 34 48 1200 15 --

21 -- -- -- 1900 19 -- 1200 34 -- 1200 8 --

22 -- -- -- -- -- -- 1200 27 -- 1200 6 72

23 -- -- -- 1900 18 84 1200 71 21 1200 12 --

24 -- -- -- -- -- -- 1200 26 -- 1200 8 --

25 -- -- -- 1900 29 -- 1200 26 -- 1200 9 68

26 -- -- -- -- -- -- 1200 21 59 1200 6 --

27 -- -- -- 1900 49 -- 1200 18 -- 1200 4 --

28 -- -- -- -- -- -- 1200 33 -- 1200 10 46

29 -- -- -- 1900 34 85 1200 43 71 -- -- --

30 -- -- -- -- -- -- 1200 21 -- -- -- --

31 -- -- -- -- -- -- 1200 13 -- -- -- --
DATA TABLES 13

Table 5. Daily mean suspended-sediment concentrations and loads for station 06037100, Gibbon River at Grand Loop Road 

Bridge at Madison Junction, Yellowstone National Park, Wyoming, April 1 through June 30, 2001

[mg/L, milligrams per liter; tons/d, tons per day; e, estimated, --, no data]

EXTREMES FOR PERIOD OF RECORD.--

SEDIMENT CONCENTRATION: Maximum daily mean during period of operation, 360 mg/L, May 16; minimum daily mean during period of 

operation, 2 mg/L, June 27.

SEDIMENT LOADS: Maximum daily mean during period of operation, 596 tons/d, May 16; minimum daily mean during period of operation, 

0.77 ton/d, June 27.

Day

Mean 

concentration

(mg/L)

Load 

(tons/day)

Mean 

concentration

(mg/L)

Load 

(tons/day)

Mean 

concentration

(mg/L)

Load 

(tons/day)

April May June

1 e12 e3.3 41 29 8 3.4

2 e14 e4.0 e35 e20 9 3.6

3 e16 e4.5 26 13 8 3.4

4 e18 e5.1 e36 e18 7 2.9

5 e20 e5.6 32 18 5 2.2

6 e22 e6.3 e32 e19 5 2.3

7 24 6.9 e38 e22 6 2.6

8 e24 e7.0 e41 e25 6 2.4

9 e22 e6.1 e50 e35 9 3.3

10 e21 e5.6 e52 e36 4 1.6

11 e19 e5.1 e36 e24 5 1.6

12 e18 e4.8 e24 e17 5 2.0

13 16 4.4 e21 e15 7 2.8

14 e14 e3.8 24 17 9 4.3

15 12 3.0 20 18 11 5.4

16 e13 e3.3 360 596 6 2.3

17 e15 e4.1 269 304 5 1.7

18 e17 e5.7 50 45 4 1.4

19 20 7.6 13 9.4 4 1.2

20 e21 e8.0 10 6.8 6 2.1

21 21 8.0 11 6.7 4 1.4

22 e21 e7.5 12 7.0 3 1.1

23 21 7.1 23 13 5 1.7

24 e25 e8.3 13 6.7 4 1.3

25 31 12 11 5.4 4 1.3

26 e41 e18 9 4.6 3 .94

27 52 28 9 4.3 2 .77

28 e49 e30 13 6.9 5 1.5

29 41 29 13 8.1 e6 e1.3

30 e40 e25 9 4.6 e6 e1.3

31 -- -- 7 3.0 -- --

TOTAL -- 277.1 -- 1,357.5 -- 65.11
14 SEDIMENTATION DATA FOR THE GIBBON RIVER, YELLOWSTONE NATIONAL PARK 

 

V*w weighted mean 0.149 (14.9 percent of residual pool volume occupied by fine sediment)

SE 0.017

Table 6. Summary of pool geometry measurements in the Gibbon River, October 2000

[Vrf, volume of fine sediment in residual pool; V*, fraction of residual pool occupied by fine sediment; Max, maximum; Dr, residual pool depth; Drc, depth 

of riffle crest; Vr, volume of residual pool (water plus sediment); m3, cubic meter; Wr, surface width of residual pool; m2, square meters; cm, centimeters; 

Std. Dev., standard deviation; C.V., coefficient of variation; V*w, volume weighted mean proportion; SE, standard error; --, not determined]

Reference 

station

Dist.

(m) Reach Vrf V*

Max Dr

(m)

Max Dr

Drc

Vr

(m3)

Mean Wr

(m)

Pool 

length 

(m)

Plan area 

(m2)

Mean Dr

(cm)

06036950 645 3 1.31 0.337 0.35 0.56 3.89 3.28 18 59.0 5.11

06036950 726 3 4.31 0.091 0.65 1.69 47.3 23.4 25 585 22.4

06037000 104 4 17.99 0.146 1.01 2.03 123 10.1 50 504 24.1

06037000 967 5 1.02 0.068 0.65 1.08 15.0 3.80 20 76.0 20.4

06037000 1058 5 32.25 0.196 0.60 1.50 164 10.7 75 800 21.2

06037000 1903 2 1.70 0.085 0.36 0.71 20.1 6.60 22 145 12.9

06037000 2104 2 3.93 0.262 0.28 0.44 15.0 6.92 35 242 7.24

06037000 2329 2 1.13 0.126 0.32 0.51 8.96 3.62 26 94.1 8.26

06037100 -3798 1 4.64 0.080 0.94 1.49 58.3 6.42 25 161 36.8

06037100 -3354 1 15.92 0.098 0.83 3.32 163 11.2 42 472 35.4

06037100 -3163 1 11.02 0.254 0.62 0.83 43.3 10.8 24 259 17.6

06037100 -2648 0 17.28 0.095 0.78 1.90 183 7.96 65 517 36.8

06037100 -2472 0 6.43 0.254 0.78 1.44 25.3 7.71 19 146 16.0

06037100 -2423 0 16.91 0.291 0.63 1.21 58.2 8.42 30 253 22.9

06037100 -454 6 30.61 0.187 1.29 3.58 163 8.52 45 383 48.1

06037100 -192 6 15.74 0.119 1.00 1.85 132 6.06 41 248 51.6

Mean 65.07 0.168 0.694 1.51 76.5 8.47 35.1 309 24.2

Std. Dev. -- -- 0.283 0.916 65.8 4.70 16.9 213 14.0

C.V. (percent) -- -- 40.9 60.7 86.1 55.6 48.1 69.0 57.8
DATA TABLES 15

Table 7. Particle-size distribution of fine bed sediment in pools, Gibbon River, October 2000[Dist., distance from reference station (positive values indicate a downstream position; negative values indicate an usptream position); m, meter; mm, millimeter; μm, mreplicate sample]

Reference 

station

Dist.

(m) Reach

Date 

sampled

Percentage finer than indicated sieve size

51 mm 25 mm 12.5 mm 4.75 mm 2.36 mm 1.18 mm 600 μm 300 μm 

06036950 645 3 10-14-00 100 100 99 95 82 52 26 8 06036950 726 3 10-14-00 100 100 98 94 74 53 38 22 06037000 104 4 10-14-00 100 100 100 98 80 43 11 2 06037000 967 5 10-15-00 100 100 98 89 56 20 6 2 06037000 1058 5 10-15-00 100 100 100 97 91 77 57 35 06037000 1058 5 10-15-00 100 100 100 98 87 67 32 9 06037000 1903 2 10-13-00 100 90 86 60 41 27 15 6 06037000 2104 2 10-13-00 100 97 88 73 62 51 30 9 06037000 2104 2 10-15-00 100 97 91 71 50 35 18 4 06037000 2329 2 10-13-00 100 100 97 82 53 30 15 6 06037100 -3798 1 10-13-00 100 100 93 76 68 64 56 29 06037100 -3354 1 10-13-00 100 100 99 95 82 66 38 15 06037100 -3163 1 10-13-00 100 100 100 87 70 63 51 18 06037100 -2648 0 10-12-00 100 100 87 82 66 43 27 12 06037100 -2472 0 10-12-00 100 88 69 55 44 33 18 4 06037100 -2423 0 10-12-00 100 100 99 89 69 46 17 6 06037100 -454 6 10-11-00 100 100 99 93 78 59 28 7 06037100 -192 6 10-11-00 100 100 99 88 70 49 16 2 
16 SEDIMENTATION DATA FOR THE GIBBON RIVER, YELLOWSTONE NATIONAL PARK Table 8. Particle-size distribution of surficial bed material in a riffle, Gibbon River, October 2000 [Numbers in bold represent the visually estimated embeddedness of individual particles. Dist., downstream distance from reference station; m, meter; n, total number o

millimeter] Station Dist. (m) Riffle Date sampled n 2 2.8 4 5.6 8 11.2 16 22.6 32 45 64 90 128 180 

Percentage finer than indicated particle size (mm) 06037000 2159 D1.5 10-15-00 101 1.0 1.0 3.0 7.9 7.9 12.9 14.9 17.8 20.8 24.8 37.6 55.4 71.3 84.2 

Estimated percent embeddedness of particle of indicated size (mm) Mean for size and class 50 65 55 50 37 44 38 45 48 

Number of particles 47 1 2 2 2 3 10 12 11 4 50 30 60 50 10 10 40 30 40 100 50 50 60 50 60 90 30 40 90 0 70 40 10 80 80 80 60 0 50 40 20 10 30 30 20 60 20 40 40 30 30 50 80 50

50 2040