Bathymetry of Walker Lake, West-Central Nevada

Abstract

the historic highstand of Walker Lake occurred in 1868 and estimated the highstand was between 4,089 feet and 4,108 feet. By 1882, Mason Valley was predominantly agricultural. The 7-26 feet decline in lake-surface altitude between 1868 and 1882 could partially be due to irrigation diversions during this time.

Simulation of the Lower Walker River Basin hydrologic system, west-central Nevada, using PRMS and MODFLOW models

“…Walker Lake depth was first documented in 1882 by Russell (1885), and estimated lake level from this date is 4,082 ft (Lopes and Smith, 2007). Routine monthly monitoring of Walker Lake level began in 1928.…”

“…In October 2007, the surface area was 32,100 acres; total water volume, 1.75 million acreft; mean depth, 54.5 ft; and maximum depth about 85 ft. The minimum altitude of the lake bottom is 3,849.3 ft and is near the center of the lake (Lopes and Smith, 2007). 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 Groundwater-level altitude, in feet NGVD 29…”

“…Along the lower part of the Walker River between Schurz and Walker Lake at about the altitude of the 1882 shoreline (4,082 ft, local datum; Lopes and Smith, 2007), the soils become more alkaline, and the riparian vegetation abruptly transitions to Tamarix ramosissima Ledeb (saltcedar). Saltcedar, also known as tamarisk, is listed by the State of Nevada as a noxious and invasive weed (Nevada Department of Agriculture, 2005;Natural Resources Conservation Service, 2008) because it is non-native and difficult to control.…”

“…Lake cells may become dry or wet as necessary to accommodate changes in lake size. The LWR_MF used relations between lake volume, area, and lake level in look-up tables derived from Lopes and Smith (2007) for Walker Lake and Katzer and Harmsen (1973) for Weber Reservoir.…”

“…Bathymetric data for Walker Lake and Weber Reservoir were used to assign altitudes of lake-cell bottoms using the composite 40-m DEM, which incorporated Walker Lake bathymetry from Lopes and Smith (2007), and Weber Reservoir bathymetry digitized from Katzer and Harmsen (1973). The Lake package in MODFLOW was used to convert the lake model cell discretization to tables relating lake volume and area to lake level for comparison with the look-up tables used by the model to compute lake level and area.…”