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Rhea P. Williams

Publications and source records attributed to Rhea P. Williams.

At least 19 recordsLinked to original sources

Estimated flood flows in the Lake Tahoe basin, California and Nevada

Lake Tahoe, the largest alpine lake in North America, covers about 192 square miles (mi 2 ) of the 506-mi 2 Lake Tahoe Basin, which straddles the border between California and Nevada (Fig. 1). In cooperation with the Nevada Department of Transportation (NDOT), the U.S. Geological Survey (USGS) estimates the flood frequencies of the streams that enter the lake. Information about potential flooding of these streams is used by NDOT in the design and construction of roads and highways in the Nevada portion of the basin. The stream-monitoring network in the Lake Tahoe Basin is part of the Lake Tahoe Interagency Monitoring Program (LTIMP), which combines the monitoring and research efforts of various Federal, State, and regional agencies, including both USGS and NDOT. The altitude in the basin varies from 6,223 feet (ft) at the lake's natural rim to over 10,000 ft along the basin's crest. Precipitation ranges from 40 inches per year (in/yr) on the eastern side to 90 in/yr on the western side (Crippen and Pavelka, 1970). Most of the precipitation comes during the winter months as snow. Precipitation that falls from June through September accounts for less than 20 percent of the annual total.

California, Nevada↗

Flood of January 1997 in the Carson River Basin, California and Nevada

Northern California and western Nevada were devastated by floods during January 1-3, 1997. Flood waters in the Carson River Basin (fig. 1) contributed to $55 million in projected damages in Douglas County and $19.5 million in Lyon County (Reno Gazette-Journal, 1997). Flooding in Douglas and Lyon Counties was extensive along the levee and irrigation systems, and agricultural land. In Carson City, damage to public facilities was estimated at $6.4 million (Reno Gazette-Journal, 1997). In late December 1996, storms built up a large snowpack (more than 180 percent of normal) in the higher altitudes of the Sierra Nevada (Daniel Greenlee, Natural Resource Conservation Service, oral commun., 1997) and also covered the valleys along the eastern Sierra Nevada. Then, a subtropical storm system originating in the central Pacific Ocean near the Hawaiian Islands brought heavy, unseasonably warm rain to the Sierra Nevada from December 30, 1996, through January 2, 1997. During this period, the Natural Resource Conservation Service recorded 16.4 inches (provisional data; Daniel Greenlee, oral commun., 1997) of precipitation at Ebbetts Pass, Calif. (8,700 feet above sea level), and the National Weather Service recorded 3.5 inches (National Oceanic and Atmospheric Administration, National Climate Data Center, written commun., 1997) at Minden (4,710 feet above sea level). Rain falling below about 10,000 feet depleted about 20 percent of the high-altitude snowpack and melted about 80 percent of the snowpack below about 7,000 feet.

California;Nevada↗

Problems with indirect determinations of peak streamflows in steep, desert stream channels

Many peak streamflow values used in flood analyses for desert areas are derived using the Manning equation. Data used in the equation are collected after the flow has subsided, and peak flow is thereby determined indirectly. Most measurement problems and associated errors in peak-flow determinations result from (1) channel erosion or deposition that cannot be discerned or properly evaluated after the fact, (2) unsteady and non-uniform flow that rapidly changes in magnitude, and (3) appreciable sediment transport that has unknown effects on energy dissipation. High calculated velocities and Froude numbers are unacceptable to some investigators. Measurement results could be improved by recording flows with a video camera, installing a recording stream gage and recording rain gages, measuring channel scour with buried chains, analyzing measured data by multiple techniques, and supplementing indirect measurements with direct measurements of stream velocities in similar ephemeral streams.

Conference Paper↗

Hydraulic geometry and sediment data for the South Fork Salmon River, Idaho, 1985-86

Hydraulic geometry, suspended-sediment, and bedload samples were collected at three sites in the upper reach of the South Fork Salmon River drainage basin from April 1985 to June 1986. Sites selected were South Fork Salmon River near Krassel Ranger Station, Buckhorn Creek, and North Fork Lick Creek. Results of the data collection are presented in this report.

Idaho↗

Data on ground-water quality for the Reno 1° x 2° quadrangle, western Nevada

Water quality data for groundwater has been compiled for the Reno 1 degree x 2 degree quadrangle which covers a portion of western Nevada. Chemical characteristics of the water are shown on a map (at a scale of 1:250,000) and on trilinear diagrams for the major ions. The data for the area is also presented in a table.

Nevada↗

Data on ground-water quality for the Walker Lake 1 degree x 2 degree quadrangle, western Nevada and eastern California

Water quality data for groundwater has been compiled for the Walker Lake 1 degree x 2 degree quadrangle which covers a portion of western Nevada and eastern California. Chemical characteristics of the water are shown on a map (at a scale of 1:250,000) and on trilinear diagrams for the major ions. The data for the area are also presented in a table. (USGS)

Open-File Report↗