Summary

Description

Section 206 of the TruckeeCarsonPyramid Lake Water Rights Settlement Act P.L. 101618, November 1990 Act authorized the purchase of water rights to support a longterm average of 25,000 acres of wetlands in Lahontan Valley, Nevada. The U.S. Fish and Wildlife Service, the lead Federal agency responsible for implementation of this section of the Act, is restricting purchases to agricultural water rights in the Carson Division of the Newlands Project. Acquisition of agricultural water rights could enhance wetland habitat conditions by securing a water supply and by reducing total dissolved solids and trace elements in agricultural drainwater entering the wetlands. Because the quality of agricultural drainwater in the Newlands Project is variable, the overall benefit of water rights acquisition to wetlands can be increased by selective purchase of water rights associated with drains contributing relatively large loads of agriculturallyinduced contaminants. This study was implemented to identify drains and drain segments in the Carson Division of the Newlands Project contributing relatively larger loads of agricultural contaminants. To accomplish this task, specific conductance of drainwater and drain discharges were measured to calculate total dissolved solids loading rates. Existing data on arsenic, boron, and selenium concentrations in detritus collected from drains in the Newlands Project were evaluated to identify drains containing relatively higher concentrations. The magnitude of this study prohibited attainment of all objectives. Limited numbers of data points each site was surveyed once also reduced the value of the study findings. Further research needs and changes in study design are identified.