Simulation of selected river diversion operations in the upper Carson River Basin, California and Nevada

Abstract

After decades of litigation and negotiation, the Truckee-Carson-Pyramid Lake Water Rights Settlement Act was passed in 1990. The law provides a foundation for developing operating criteria for interstate allocation of water to meet demands for municipal, irrigation, fisheries and wildlife, and recreational uses, as well as to meet water-quality standards, in the approximately 7,000square-mile Truckee River and Carson River Basins of eastern California and western Nevada (fig. 1). The Truckee-Carson Program of the U.S. Geological Survey (USGS) is assisting the U.S. Department of the Interior in implementing the act. The program has the following objectives: Consolidate streamflow and water-quality data from several agencies into a single data base; Establish new streamflow and water-quality gaging stations for more complete water-resources information and more consistent support of river operations; and Build, calibrate, test, and apply interbasin hydrologic computer models to support efficient water-resources planning, management, and allocation. Berris (1996) and Hess (1996) describe the current progress of the Truckee-Carson Program objectives. Hydrological Simulation Program-Fortran A computer model simulating storage and flow of the water in the Truckee River and Carson River Basins and in the Truckee Canal is being developed to help meet the third objective of the Truckee-Carson Program. The model, based on the Hydrological Simulation Program-Fortran (HSPF; see Bicknell and others, 1993), simulates reservoir and diversion operations to analyze alternative water-management scenarios. This fact sheet summarizes some of the capabilities that were added to HSPF to simulate complex river diversion operations in the upper Carson River Basin in eastern California and western Nevada. Examples include river diversion operations based on existing and possible agricultural or municipal and industrial demands, and operations used to divert water and fill reservoirs. River diversion operations are the distribution of waters based on legal decrees that govern the right to beneficial use of water established in accordance with the western system of appropriative water rights.' In this summary, simplified or isolated examples are used to illustrate specific operations that can be represented by Appropriative legal water rights in the Nevada parts of the Carson River and Truckee River Basins are based on the concept of "first in time, first in right." This means the first person to take a quantity of water and put it to beneficial use has a higher priority of right than a subsequent appropriative user. An appropriator usually is assigned a priority date (date of established water right). This date in relation to dates assigned to other users for the use of the same source of water is significant when the quantity of available water is insufficient to meet all the needs of all the legal users. TRUCKEE RIVER A '-BASIN ' 20 MILES CARSON RIVER 20 KILOMETERS j''-/

River and Reservoir Operations Model, Truckee River basin, California and Nevada, 1998

“…Berris (1996) developed a physically based flow-routing model of the Truckee River. The model routed daily mean streamflow along 114 miles (mi) of the mainstem Truckee River from just downstream from Lake Tahoe, Calif., to just upstream from Pyramid Lake, Nev. Hess (1996) developed a similar flow-routing model for the Carson River from the gaging station at East Fork Carson River near Markleeville, Calif., (italicized words are formal names for data-collection sites) and the gaging station at West Fork Carson River at Woodfords, Calif., to the gaging station Carson River at Fort Churchill, Nev., just upstream from Lahontan Reservoir. Selected reservoir and river operations added to the Truckee and Carson River flow-routing models are described by Berris and others (1996) and Hess (1997), respectively.…”

“…Methods to construct the Truckee Canal and Little Truckee River parts of the flow-routing model were similar to those used in the Truckee River (Berris, 1996) and the Carson River (Hess, 1996) flow routing models. Very little observed flow data or diversion data are available to compare observed and simulated daily streamflows for these added reaches.…”

River-operations model for upper Carson River Basin, California and Nevada

“…Flow-routing models of the Truckee River (Berris, 1996) and upper Carson River (upstream from Lahontan Reservoir; Hess, 1996), major tributaries, lakes/reservoirs, and the Truckee Canal.…”

“…Geologic components of the ground-water reservoir were defined and estimates were made of the distribution of hydraulic properties of aquifer materials and water-budget components throughout the valley. Hess (1997) summarized some of the capabilities of the upper Carson River operations model. Examples of operations described in Hess (1997) include diversions to meet agricultural and M&I demands, and diversions to fill reservoirs.…”

“…Hess (1997) summarized some of the capabilities of the upper Carson River operations model. Examples of operations described in Hess (1997) include diversions to meet agricultural and M&I demands, and diversions to fill reservoirs. Hess (1996)…”