During the last quarter of the 19th century, farmers and cattlemen established communities in the Walker Basin, part of the ancestral home of the Northern Paiute people. Natural flows from the Walker River were diverted to support hay, pasture and other irrigated crops.
In the 1920s, the newly formed Walker River Irrigation District built a pair of dams on the east and west forks of the Walker River to store winter and early spring runoff for use later in the season when natural flows could not sustain the need of irrigated agriculture. Additionally, in 1935 the Bureau of Indian Affairs (BIA) built Weber Dam on the lower Walker River to capture surplus flows for irrigation on the Walker River Paiute Tribe’s Reservation.
For decades, diversions from the river have sustained a strong agricultural economy but produced an unintended consequence: dramatically reduced freshwater inflows to Walker Lake, a natural desert terminal lake at the terminus of the Walker River in Nevada.
As a result of declining water levels, Total Dissolved Solids (TDS) in Walker Lake has increased dramatically to the point that the lake can no longer support its native fish and wildlife populations. The primary purpose of the Walker Basin Restoration Program (WBRP) is to acquire water from willing sellers to restore and maintain Walker Lake
Impact of Salinity on Wildlife
As part of understanding the overall condition of Walker Lake, it is important to identify key categories of “indicator species.” As salinity levels of the lake fluctuate with rising or falling lake elevation, the health of indicator species can be used to determine the overall condition of the lake ecosystem.
2017 Water Year
Winter 2017 saw historic snowpack numbers in the Sierra Nevada. The Walker Basin received approximately 300 percent of average. This snowpack and subsequent snowmelt has led to large inflows to Walker Lake. 2017 is the first time the Walker River has reached Walker Lake since 2011.
The U.S. Geological Surveys has completed many simulations for inflows to Walker Lake and predicts the lake will rise by as much as 15 to 18 feet this year, the most in a single year in recorded history. As of June 28, 2017, the lake has risen by 9.25 feet and increased its volume by 260,000 acre-feet of water since the beginning of February. Correspondingly, the lake’s TDS levels have fallen from 29,000 mg/L in February to 25,500 mg/L in mid-May. By the end of the summer the lake’s salinity should be reduced to 21,000 mg/L.
Restoration Goal for Walker Lake
WBRP’s restoration goal is to increase natural flows in the Walker River to restore and maintain Walker Lake to a long-term TDS average between 10,000 mg/L and 12,000 mg/L. This is the range where indicator species will once again be abundant in Walker Lake. The map to the left shows historic contour lines for Walker Lake. Program Goal #1 (12,000 mg/L) has an elevation of 3950 ft. and Program Goal #2 (10,000 mg/L) has an elevation of 3965 ft. The last time the lake was at these elevations was 2001 and 1998 respectively.
Us geological survey hydro mapper
This mapping application provides a basin-wide perspective of real-time streamflow and lake and reservoir storage capacity and stage for the Walker River Basin in Nevada and California. The Hydro Mapper also provides access to historic streamflow, and lake and reservoir data. This tool was developed to create a common operating picture for water users in the Walker Basin and to help monitor changes to instream flows associated with the Walker Basin Restoration Program.
Communities of Walker Lake
Hawthorne and other Walker Lake communities in Mineral County have relied on the lake for conservation, recreation and as a source of economic support.