Marcus Flats, Washington, at the northern end of the study boundary. The photo is looking northwest near the 

confluence of the Kettle and Columbia Rivers. Photograph by Rhonda J. Weakland, Dec. 2009.

EXPLANATION

Black-colored

particles

Study area

Underwater video

survey points

0

0

0.1

0.1

0.2 0.3

0.3 0.4 0.5 KILOMETER

0.4

0.2

0.5 MILE

118°07’ 118°06’

48°40’

48°39’

Figure 4B. Marcus Flats. Black-colored particles as mapped with underwater video during March 2009 near Kettle Falls, Wash. RM, river mile.

RM 705

EXPLANATION

Sediment class

Bedrock

Gravel with sand

Sand with silt

Silt

Underwater survey video points

0

0

0.1

0.1

0.2 0.3

0.3 0.4 0.5 KILOMETER

0.4

0.2

0.5 MILE

118°07’ 118°06’

48°40’

48°39’

Figure 3B. Marcus Flats sediment facies as mapped with underwater video during March 2009. RM, river mile.

RM 705

118°07’ 118°06’

48°40’

48°39’

Figure 2B. Elevation of the Lake Roosevelt bed at Marcus Flats as mapped with a multibeam echo sounder during October 2008. 

RM, river mile.

1,119–1,137

1,138–1,152

1,153–1,165

1,166–1,176

1,177–1,187

1,188–1,194

1,195–1,200

1,201–1,207

1,208–1,217

1,218–1,228

1,229–1,239

1,240–1,251

1,252–1,262

1,263–1,271

1,272–1,283

Riverbed elevation,

in feet

EXPLANATION

0

0

0.1

0.1

0.2 0.3

0.3 0.4 0.5 KILOMETER

0.4

0.2

0.5 MILE

117°56’

48°50’

48°49’

Figure 4A. China Bend. Location of black-colored particles as mapped with underwater video during March 2009 Wash. 

RM, river mile.

RM 725

0

0

0.1 0.2

0.2

0.3 0.4 0.5 MILE

0.1 0.3 0.4 0.5 KILOMETER

EXPLANATION

Black-colored

particles

Study area

Underwater video

survey points

117°56’

48°50’

48°49’

Figure 3A. China Bend sediment facies as mapped with underwater video, March 2008. RM, river mile.

RM 725

0

0

0.1 0.2

0.2

0.3 0.4 0.5 MILE

0.1 0.3 0.4 0.5 KILOMETER

EXPLANATION

Sediment class

Clean gravel

Gravel with sand

Clean sand

Sand with silt

Underwater video

survey points

117°56’ 117°55’

48°50’

48°49’

Figure 2A. Elevation of the Lake Roosevelt bed at China Bend as mapped with a multibeam echo sounder during October 2008. RM, river mile.

0

0

0.1 0.2

0.2

0.3 0.4 0.5 MILE

0.1 0.3 0.4 0.5 KILOMETER

Riverbed elevation,

in feet

EXPLANATION

1,195–1,204

1,205–1,211

1,212–1,217

1,218–1,222

1,223–1,226

1,227–1,230

1,231–1,235

1,236–1,240

1,241–1,245

1,246–1,251

1,252–1,257

1,258–1,262

1,263–1,267

1,268–1,273

1,274–1,281

172

17

174

155

174

2

155

21

25

25 231

291

97

20

21

395

395

292

231

20

20

25

2

31

Grand Coulee

Dam

GRANT 

DOUGLAS 

Banks

Lake

LINCOLN

Franklin D. Roosevelt Lake

Hawk 

Creek

Rufus Woods

Lake

Nespelem

Ninemile Creek

SPOKANE

Fort

Spokane

Hunters

Long Lake

Dam

Spokane River

Franklin D. Roosevelt Lake

Long Lake

Columbia River

Republic

Sanpoil

River

Kettle

River

Marcus

Flats Kettle Falls Sherman Creek

Sanpoil River

FERRY

Hall

Creek

Inchelium

Franklin D. Roosevelt Lake

Spokane

River

Littl e Spokane R

STEVENS

Colville

Colville

River

PEND

OREILLE

Pend Oreille

River

Boundary 

Dam

China

Bend

Northport

Sevenmile

Dam

Trail

Hugh

Keenleyside

Dam

Castlegar

Hanna Cr

Kooteney R

Lower Arrow

Lake

Brilliant

Dam

Columbia

River

COLUMBIA

RIVER

OKANOGAN

48°30’

49°00’ 119°00’ 118°30’ 118°00’

48°00’

Waneta

Dam

Little Falls

Dam

UNITED STATES

CANADA

0 5 10

10 15

20 MILES

0 5 20 KILOMETERS

COLVILLE

INDIAN RESERVATION

SPOKANE

INDIAN RESERVATION

OKANOGAN

NAT FOR

ONF

ONF

ONF

COLVILLE

NATIONAL FOREST

COLVILLE

NATIONAL FOREST

CNF

CNF

CNF

Grand

Coulee

LITTLE PEND

OREILLE

NWR

LAKE ROOSEVELT

NATIONAL

RECREATION AREA

Figure 1. Site map and location of Marcus flats and China Bend study reaches. Shaded relief from U.S. Geological Survey Landsat 

Tri-decadal State satellite Mosaic Washington, 2001, available from the USGS Store at http://usgs.store.gov/. Lake Roosevelt National 

Recreation Area boundary accessed on Dec. 16, 2010 at http://www.nps.gov/carto/PDF/LAROmap1.pdf. Colville National Forest 

boundary from the U.S. Dept. of Agriculture National Forest Service accessed on Dec. 16, 2010 at http://www.fs.fed.us/r6/datalibrary/gis/colville/index.shtml, Okanogan National Forest Service boundary at http://www.fs.fed.us/r6/data-library/gis/okanogan/index.shtml, 

Little Pend Oreille National Wildlife Refuge boundary from http://www.fws.gov/littlependoreille/pdf/PublicUseRefugeMap.pdf. Spokane 

Indian Reservation boundary accessed on Dec. 16, 2010 at http://www.spokanetribe.com/reservation. Colville Indian Reservation 

Boundary from http://www.colvilletribes.com/map%20of%20non%20tribe%20camp.html. River miles from National Oceanic and 

Atmospheric Administration (NOAA), Office of Coast Survey at http://www.nauticalcharts.noaa.gov/. All boundaries are generalized 

and approximately located and for display purposes only. Inholdings have not been shown.

RM 725

RM 705

RM 615

RM 640

RM 675

RM 740

CANADA

UNITED STATES

WASHINGTON

Lake

Roosevelt

area

Black Sand

Beach

White sturgeon in Columbia River. Photograph taken by Michael Parsley (USGS) at the fish viewing pond at Bonneville Dam. 

Middle of Lake Roosevelt. Photograph by L. Snook, National Park Service. Available at http://www.nps.gov/laro/parkmgmt/businesswithpark.htm.

Measuring a white sturgeon (Acipenser transmontanus). Photograph by USGS staff; record number 10469; date 

published, Sept. 27, 2008; image originally taken in May 1999. Published by National Biological Information Infrastructure, 

available at http://life.nbii.gov/dml/home.do.

Bathymetric and Sediment Facies Maps for China Bend and Marcus Flats,

Franklin D. Roosevelt Lake, Washington, 2008 and 2009

By Rhonda J. Weakland, Ryan L.Fosness, Marshall L. Williams, and Gary J. Barton

2011

Scientific Investigations Map 3150

U.S. Department of the Interior

U.S. Geological Suvey

Publishing support provided by: 

Denver Publishing Service Center

Manuscript approved for publication on January 31, 2011

For more information concerning this publication, contact:

Director, Washington Water Science Center

U.S. Geological Survey

934 Broadway, Suite 300

Tacoma, WA 98402

(253)522–1600

Or visit the Washington Water Science Center Web site at:

http://wa.water.usgs.gov/ 

This report is available at: http://pubs.usgs.gov/sim/3150/. 

Suggested citation:

Weakland, R.J., Fosness, R.L., Williams, M.L., and Barton, G.J., 2011, 

Bathymetric and sediment facies maps for China Bend and Marcus 

Flats, Franklin D. Roosevelt Lake, Washington, 2008 and 2009: U.S. 

Geolgical Survey Scientific Investigations Map 3150, 1 sheet.

Background image: About four miles below Boundary Post Office. 

Terrace on west side of Columbia River, direction northwest. Stevens 

County, Wash., August 1901. Image from USGS Photographic Library, 

ID Ransome, F.F., 087, rfl00087.

This and other USGS information products are available at

http://store.usgs.gov/

U.S. Geological Survey

Box 25286, Denver Federal Center

Denver, CO 80225

To learn about the USGS and its information products visit

http://www.usgs.gov/

1-888-ASK-USGS

Any use of trade, product, or firm names is for descriptive

purposes only and does not imply endorsement by the

U.S. Government.

Not for navigational use

China

Bend

Marcus

Flats

Basemap images (dated 2004) for figures 2A–4A and 2B–4B from U.S. 

Department of Agriculture, Farm Service Agency, Aerial Photography Field 

Office, National Agriculture Imagery Program (NAIP) available at: 

http://www.apfo.usda.gov/FSA/apfoapp?area=home&subject=prog&topic=nai-or 

Drawing of sturgeon done by Nonindigenous Aquatic Species

(NAS, http://nas.er.usgs.gov/).

CONVERSION FACTORS

Multiply By To obtain

inches (in)

foot (ft)

mile (mi)

2.54

0.3048

1.609

centimeter (cm)

meter (m)

kilometer (km)

0.2642

Elevation, as used in this report, refers to distance above the vertical datum.

Vertical coordinate information is referenced to the North American Vertical

Datum of 1988 (NAVD 88).

Concentrations of chemical constituents in water are given in (μg/L).

gram (g)

kilogram (kg)

gallon (gal)

Mass

ounce, avoirdupois (oz)

2.205 pound, avoirdupois (lb)

0.03527

Inch/Pound to SI

SI to Inch/Pound

Length

Volume

liter (L)

Introduction

In support of an interdisciplinary study of white sturgeon (Acipenser transmontanus) and 

their habitat areas within Franklin D. Roosevelt Lake, Washington (hereinafter referred to as 

Lake Roosevelt), the U.S. Geological Survey (USGS) created bathymetric and sediment facies 

maps for portions of two reaches of Lake Roosevelt. The mapping effort focused on utilizing 

noninvasive study techniques to characterize the elevation, texture, and grain size of the 

lakebed surface in areas used by Lake Roosevelt white sturgeon fry. Surface relief was 

characterized by using a multibeam echo sounder to generate bathymetric data. The purpose 

of this research is to aid future physical sampling efforts focusing on areas that have the 

greatest potential to find smelter slag contamination, while reducing the effect on the environment or culturally sensitve areas through random sampling. Past research has indicated that 

smelter slag often looks like black sand particles. Videography sampling in the survey area 

allows for characterizing sediment facies by grain size, areas of sand deposition, and in some 

cases, depending upon light availability, color. This survey has identified areas containing 

black-colored particulate matter that may be elements and minerals, organic material, or slag.

The white sturgeon population in Lake Roosevelt is threatened by the failure of natural 

recruitment, resulting in a native population that consists primarily of aging fish that is gradually declining as fish die and are not replaced by nonhatchery reared juvenile fish. Many newly 

hatched native sturgeon fry have been observed in previous years in the upper riverine 

reaches of Lake Roosevelt; however, recent assessments of sturgeon population structure 

indicate that native juvenile sturgeon do not survive to sexual maturity. These fish spawn and 

rear in the riverine and upper reservoir reaches where smelter slag is present in the sediment 

of the river and lake bed (Howell and McLellan, 2005; U.S. Environmental Protection Agency, 

2006). 

Tons of granulated (sand-sized) slag has been discharged into the Columbia River and 

subsequently transported downstream by river currents as part of the sediment load where 

slag may have been deposited in river bars and quiescent regions of Lake Roosevelt (Cominco, 

1991; G3 Consulting Ltd., 2001; Northwest Hydraulic Consultants, 2007). During periods of low 

reservoir stage, slag has been observed among the interstitial sediments of exposed gravel 

bars that are believed to be used as habitat by newly hatched sturgeon fry during their hiding 

phase. Some large deposits of slag, such as the one at Black Sand Beach, are well documented, but the location of much of the deposited slag material is not well documented or 

known. A conceptual site model for sediments in Lake Roosevelt based on grain-size distribution and analysis of channel cross-sectional area hypothesize that most of the slag has been 

deposited in the pre-reservoir river channel area near Marcus Flats (U.S. Environmental 

Protection Agency, 2006). However, other large deposits of slag may occur as much of the bed 

sediments in the riverine reach were not sampled due to the difficulty of sampling interstitial 

sediments present in the gravelly boulder substrate of the swiftly flowing reaches. Granulated 

slag particles have distinctive morphological features that have been described by Cominco 

Ltd. (1991) and Cox and others (2005). Slag grains typically are black sand-size particles with a 

smooth, glassy surface often containing vugs and a combination of smooth, rounded and 

angular surfaces often with needle-like projections and an appearance similar to that of 

eggshells. The surface appearance is often lustrous in relatively unweathered grains. When 

examined with a petrographic microscope, slag grains are opaque under polarized light. 

Effects of slag on the white sturgeon population in Lake Roosevelt are largely unknown, 

but recent studies indicate that slag may harm white sturgeon and (or) their young. Recent 

studies demonstrated that copper and other metals can be mobilized from slag containing 

sediments (Paulson and Cox, 2007). In the riverine reach of Lake Roosevelt, concentrations of 

copper and zinc in bed sediments can reach levels of 10,000 and 30,000 mg/kg due to the 

presence of smelter slag (U.S. Environmental Protection Agency, 2006). In a separate study, 

copper was found to be highly toxic to 30-day-old white sturgeon with 96–h LC50 ( 96–h, 

96–hour exposure; LC50, median lethal concentration which kills 50 percent of the population) 

concentrations ranging from 3 to 5 μg copper per liter (Edward E. Little, U.S. Geological Survey, 

Columbia, Mo., written commun., 2009). Older juvenile and adult sturgeons commonly ingest 

substantial amounts of sediment while foraging. Thus, fish foraging in slag-contaminated 

sediments likely have slag particles in their guts. The physical properties of slag particles may 

contribute to environmental stress that has detrimental effects on the gut tissue as they pass 

through the spiral intestine (Parsley and others, 2010). These studies suggest that slag may 

have adverse effects on white sturgeon fry and juvenile age groups. Resource managers for 

the Lake Roosevelt ecosystem need additional information about the factors and processes 

that may affect the abundance of the white sturgeon. Identifying areas of where slag could 

potentially accumulate within the white sturgeon habitat areas of Lake Roosevelt is important 

in evaluating potential effects of the slag. Past coarse-scale telemetry studies have shown that 

white sturgeons seasonally occupy the Marcus Flats reach. It has been noted that considerable quantities of slag are present in the old river channel in the vicinity of Marcus Flats (U.S. 

Environmental Protection Agency, 2006).

Purpose and Scope

In October 2008, scientists from the USGS used a boat-mounted multibeam echo sounder 

(MBES) to collect bathymetric data at China Bend and Marcus Flats. In March 2009, an 

underwater video camera was used to collect sediment facies data from the same areas. 

These data were used to construct bathymetric and sediment facies maps for China Bend and 

Marcus Flats. This report presents bathymetric and sediment facies maps of China Bend and 

Marcus Flats for Lake Roosevelt, between Northport and Kettle Falls, Washington. These maps 

can be used to help identify areas that may contain slag within the riverbed deposits. This 

study was conducted by the USGS as part of a broader study examining white sturgeon habitat 

and the occurrence and effects of smelter slag on white sturgeon populations in the upper 

Columbia River. Together this information may be useful in efforts to locate areas of potential 

smelter-slag accumulation. 

Description of the Study Area

Lake Roosevelt is a reservoir in Washington on the Columbia River impounded by Grand 

Coulee Dam. The reservoir extends northward for about 151 miles to the United States–Canada 

border (fig. 1). The Columbia contributes about 70 percent of the inflow into Lake Roosevelt. 

Sediment transported and deposited into Lake Roosevelt is primarily derived from the inflowing 

Columbia River, tributary streams and rivers, landslides, and erosion of unconsolidated 

sediment along the margins of the reservoir (Cox and others, 2005). Inflow of suspended 

sediment to Lake Roosevelt is depleted as a result of sediment trapping by numerous upstream 

dams such as Waneta and Sevenmile Dams on the Pend Oreille River and Long Lake Dam on 

the Spokane River.

China Bend is located at river mile (RM) 725, approximately 10 miles southwest of Northport, Wash., and Marcus Flats is located at RM 705, less than 5 miles northwest of Kettle Falls, 

Wash. (fig. 1). The Washington Department of Fish and Wildlife have used acoustic telemetry 

to track sturgeon movement in the Upper Columbia River and verified white sturgeon live, 

spawn, and stage as juveniles in these study areas (Howell and McLellan, 2005). Granulated 

slag was discharged into the Columbia River until 1995 from lead-zinc smelters upstream from 

Lake Roosevelt (G3 Consulting Ltd., 2001). The slag was transported downstream and can now 

be found within the reservoir sands and gravels and along the shoreline (Northwest Hydraulic 

Consultants, 2007; Majewski and others, 2003). 

Methods and Techniques

The MBES was used in October 2008 to map the bed elevation of Lake Roosevelt at China 

Bend, river miles (RM) 725.2 to 724.0, and Marcus Flats, RM 707.3 to 704.9. The referenced bed 

elevation is based on North American Vertical Datum 1988 (NAVD88). The MBES uses a 

240–kilohertz (kHz) pulse over a 120-degree-wide swath to profile the bathymetry of the lake 

bottom. The MBES data were collected using Hypack® hydrographic survey software 

(available at http://www.hypack.com/new), and were processed through Hysweep® collection 

and editing software to produce a digital elevation model (DEM, a regularly spaced grid of 

elevation points) on a 10-ft grid. The grid spacing provided a high-resolution surface that 

displayed sand dune formations, rock outcroppings, and other unique features that aid in the 

development of the sediment facies maps. The DEMs were imported into geographical 

information system (GIS) software to create bathymetric maps at China Bend and Marcus Flats 

(figs. 2A and 2B). 

Sediment facies were determined in March 2009 by using a tethered high-resolution, color 

video camera. The predominant particle size of sediment at the riverbed surface was determined using two parallel lasers with 4-inch separation mounted on the camera housing. Video 

images were captured at discrete points along numerous cross sections through the study 

areas, allowing for sufficient detail to map distinct changes in sediment facies. Sediment 

facies classifications: gravel, sand, and silt, were characterized according to sediments 

observed in the video images (figs. 3A and 3B). Each cross section contained video points 

spaced apart by about 100 ft. The total number of video points per cross section varied with the 

width of the cross section. Cross sections were drawn at major deviations in channel bathymetry 

to capture changes in sediment facies and possible presence of black-colored particles (fig. 

4A and 4B). Sediment facies categories used in construction of the facies map were based on 

the grain size distribution of Wentworth (1922) which included the following ranges: bedrock, 

gravel (greater than 0.08 to 2.5 inches), sand (0.002 inch to less than 0.08 inch), and silt (fines) 

(less than 0.002 inch). 

Results

Results of the digital elevation model for the China Bend reach, based on the 10-ft-grid 

spacing of the MBES survey, show deeper water (dark blue colored areas with depths ranging 

from 85 ft to 90 ft, from water surface) and corresponding riverbed elevations of 1,194 ft to 1,203 

ft. (fig. 2A). The areas of greater depth were found on the outside of the river meander where 

higher streamflow velocities and bed scour are expected. Conversely, shallower regions were 

observed on the inside of the meander were depositional areas would be expected. The 

narrow stream channel at China Bend allows for higher streamflow velocity, resulting primarily 

in clean gravel along the channel bottom and gravel with sand along the channel margins. 

Clean gravel and gravel with sand were the predominant sediment facies in this reach (fig. 3A). 

Deposits that were predominantly sand and silt were evident in isolated areas along the inside 

channel margins and toward the downstream end of the reach. However, sand and fine 

grained sediments were apparent in some of the interstitial spaces between gravel and cobble 

material. Most areas of sediment accumulation were along the inside of the point bar and 

toward the downstream end of the bar where sand facies were more often observed. Areas of 

scour occur all along the outer perimeter of the river bend. Black-colored particles identified in 

China Bend are depicted in figure 4A. Sediment that contains these particles was found both in 

depositional and erosional environments of the study areas.

The digital elevation model of Marcus Flats based on the MBES survey is shown in fig. 2B. 

The dark blue color represents a hole about 165 ft deep from the water surface; riverbed 

elevation ranged from 1,118 ft to 1,138 ft, coinciding with an area of exposed basalt where 

sediment has been scoured from the river bottom. The DEM shows what appear to be sand 

dunes; dune height on the order of 2–3 feet is present in the downstream portion of Marcus 

Flats. The sediment facies map in figure 3B indicates a predominance of sand with silt, 

interspersed with areas of gravel embedded in the sand and silt. Silt deposits were observed 

along the western edge of Marcus Flats. Black-colored particles that were identified in areas 

of Marcus Flats are depicted in figure 4B. Sand deposits that contained these particles were 

found both in depositional and erosional environments of the study areas.

Future study efforts in Lake Roosevelt could include sampling of bottom material to 

confirm the presence or absence of possible slag material. In addition, follow-up acoustic 

work to determine stream velocities at varying discharges, in conjunction with sediment 

mapping, would be helpful to more accurately identify areas of scour and areas of sediment 

deposition where slag deposits may accumulate within the Marcus Flats and China Bend 

reaches. MBES mapping could also be used to determine changes in bed elevation and 

sedimentation in the study reaches and could help evaluate annual deposition and provide 

estimates on fine-sediment thickness. 

Acknowledgments 

The authors thank Theresa D. Olsen of the USGS Washington Water Science Center for 

generating the bathymetric maps in GIS, and the staff at the National Park Service Lake Roosevelt 

National Recreation Area for providing storage facilities for the USGS survey boat and equipment. 

References Cited

Cominco, Ltd., 1991, Slag disposal options—Environmental and engineering studies: Trail, B.C., 

Trail operations, Cominco Metals Environmental Management Program, 24 p. 

Cox, S.E., Bell, P.R., Lowther, J.S., and VanMetre, P.C., 2005, Vertical distribution of trace-element 

concentrations and occurrence of metallurgical slag particles in accumulated bed sediments 

of Lake Roosevelt, Washington, September 2002: U.S. Geological Survey Scientific Investigations Report 2004–5090, 70 p. Available at http://pubs.usgs.gov/sir/2004/5090/. 

G3 Consulting, Ltd., 2001, Assessment of Columbia River receiving waters—Final report, prepared 

for Teck-Cominco Ltd., Trail Operations: Surrey B.C., G3 Consulting Ltd., 183 p. Available at 

http://www.teck.com/Generic.aspx?PAGE=Teck+Site%2fDiversified+Mining+Pages%2fZinc+P

ages%2fTrail+Pages%2fEcological+Risk+Assessment+Pages%2fReports&portalName=tc.

Howell, M.D., and McLellan, J.G., 2005, Lake Roosevelt white sturgeon recovery project annual 

progress report to the Bonneveille Power Administration, January 2004–March 2005: Washington Department of Fish and Wildlife. Available at 

http://www.fishsciences.net/projects/columbia_sturgeon/_pdfs/36-L_Roosev_w-st_recov_Ja

n_04-Mar_05.pdf. 

Majewski, M.S., Kahle, S.C., Ebbert, J.C., and Josberger, E.G., 2003, Concentrations and distribution of slag-related trace elements and mercury in fine-grained beach and bed sediments of 

Lake Roosevelt, Washington, April–May 2001: U.S. Geological Survey Water-Resources 

Investigations Report 2003–4170, 29 p. Available at http://pubs.usgs.gov/wri/wri034170/. 

Northwest Hydraulic Consultants Ltd., 2007, Columbia River substrate investigation, prepared for 

British Columbia Ministry of Environment, B.C. Hydro and Power Authority, and Columbia 

River Integrated Environmental Monitoring Program: North Vancouver, B.C., Northwest 

Hydraulic Consultants Ltd., 40 p.

Parsley, M.J., van der Leeuw, B.K., and Elliott, D.G., 2010, Characterization of the contents and 

histology of the gastrointestinal tract of White Sturgeon (Acipenser transmontanus) captured 

from Upper Lake Roosevelt, Washington, October 2008: U.S. Geological Survey Open-File 

Report 2010–1193, 24p. Available at http://pubs.usgs.gov/of/2010/1193/. 

Paulson A.J., and Cox, S.E., 2007, Release of elements to natural water from sediments of Lake 

Roosevelt: Environmental Toxicology and Chemistry, v. 26, no. 12, p. 2550–2559. 

U.S. Environmental Protection Agency, 2006, Region 10, Phase 1 sediment sampling data evaluation upper Columbia River Site CERCLA RI/FS, August 2006: Seattle, Wash., CH2MHill for EPA 

contract no. 68–S7–04–01 SPK/062360001, 363 p. Available at 

http://yosemite.epa.gov/r10/CLEANUP.NSF/82751e55bf4ef18488256ecb00835666/0d26a0706057

8af988256ecc0075d161/$FILE/Section%201.pdf.

Wentworth, C.K., 1922, A scale of grade and class terms for clastic sediments: The Journal of 

Geology, v. 30, p. 377–392.

Location

of image

Still shots from the tethered 

high-resolution underwater 

video camera taken at China 

Bend. Latitude and longitude 

coordinates and time stamps 

are visible on the images. Red 

lines and illuminated spots 

are caused by the laser 

beams from the camera. 

Image taken by the authors.

Still shots from the tethered 

high-resolution underwater 

video camera taken at China 

Bend. Latitude and longitude 

coordinates and time stamps 

are visible on the images. Red 

lines and illuminated spots 

are caused by the laser 

beams from the camera. The 

darker areas interspersed 

with the cobbles and 

sediment are the 

black-colored particles. 

Image taken by the authors.

Location

of image

Still shots from the tethered 

high-resolution underwater 

video camera taken at 

Marcus Flats. Latitude and 

longitude coordinates and 

time stamps are visible on the 

images. Red lines and 

illuminated spots are caused 

by the laser beams from the 

camera. The darker areas are 

the black-colored particles. 

Image taken by the authors.

Location

of image

Location

of image

Still shots from the tethered 

high-resolution underwater 

video camera taken at 

Marcus Flats. Latitude and 

longitude coordinates and 

time stamps are visible on the 

images. Red lines and 

illuminated spots are caused 

by the laser beams from the 

camera. The darker areas are 

the black-colored particles. 

Image taken by the authors.