Amidst all the excitement this summer about the 150th anniversary of the founding of Tahoe City, let’s not forget that 2013 also is the 100-year mark for the final construction of the Tahoe Dam, arguably the town’s most important landmark. Completed in 1913, this modest 17-gate dam regulates all of Lake Tahoe’s reservoir capacity and serves entities and people in California and especially Nevada.
In the 1890s, Nevada congressman Francis G. Newlands proposed a network of reservoirs in the Sierra to serve the future development of the Silver State. According to Newlands, Tahoe afforded the “cheapest reservoir space in the West.” Newlands sponsored a measure through which the federal government would ultimately dam every major river in the West to provide water for irrigation in arid regions. After passage of the Newlands Reclamation Act, the Department of the Interior notified California and Nevada officials that the federal government would be assuming the right to control the water stored in Lake Tahoe behind the dam. The new legislation led the construction of the Derby Dam, the Truckee Canal and Lahontan Reservoir.
By 1905, the first stages of the Newlands Reclamation Project were well under way. That year, the government finished building the Derby Dam, located 11 miles upstream of Wadsworth, Nev., on the lower Truckee River.
The following year, the Truckee Canal was completed so that water diverted at Derby Dam could begin flowing through the 32 miles long canal south to the Carson River. The Truckee River water was then used to irrigate vast acreage for agricultural development in what previously had been desert. But, there were problems from the start.
Without upstream storage on the Carson River, the project’s agricultural season was subject to variations in river flow based on winter precipitation in the Sierra. As a result, during dry years the growing season was shortened and production limited. To help mitigate these erratic fluctuations in river flow, in 1915 the Lahontan Dam and Reservoir was completed upstream from the project’s farms. The Truckee Canal was then redirected to dump Truckee River water into the reservoir instead of directly into the Carson River. The Truckee Canal has a nominal capacity of 900 cubic feet per second, which is enough water to irrigate 64,000 acres.
In 1913, another important piece to this scheme of water diversion was put into place with the completion of the modern concrete Tahoe Dam at the lake’s outlet in Tahoe City. The previous dam had been owned and operated by the Truckee River General Electric Company, which in 1908 had formed an agreement with two other Nevada entities to insure a minimum flow in the Truckee River throughout the year. These agreed upon Floriston flow rates were later incorporated into the Truckee River General Electric Decree in 1915, a decree which settled a long-standing controversy over who would control and operate the Lake Tahoe Dam.
One bone of contention occurred in 1907 when the power company prematurely released too much water, which cut short the amount available for Nevada farmers. The federal government eventually gained control over the operation of the dam through the 1915 decree, but it was forced to maintain the Floriston rates, which granted the power company minimum in-stream flows in order to generate electricity at several power houses along the river’s reach. Today, the Tahoe Dam and the entire Newlands Project is maintained and operated by the Truckee-Carson Irrigation District. The TCID was formed in 1918 for the purpose of representing the farmers and water right holders within the boundaries of the Newlands Project.
The Newlands diversion and irrigation project has been serving Western Nevada for more than 100 years, but the engineers who planned it miscalculated and overestimated the reliability of the Truckee River water supply. Angry farmers who had been lured to the project rebelled over water shortages during the growing season. The Paiute Indian Tribe at Pyramid Lake below the Derby Dam was severely affected by the interbasin water transfer. To address concerns by the Paiute Tribe, a U.S. government treaty promised it enough water to maintain their historic fishery at the mouth of the river. Despite these assurances, the Derby Dam cut water flow into Pyramid Lake by half.
In 1891, the lake’s surface elevation measured 3,878 mean sea level, but by 1967 the water had fallen to 3,783, a drop of more than 94 feet. Even more importantly, the water diversion has significantly reduced Pyramid Lake’s total volume resulting in increased salinity and dissolved solids. The degradation of water quality along with warmer water temperatures in the lower Truckee River due to both reduced river flows and discharges from a water treatment facility have combined to jeopardize the lake’s continued existence as a viable fishery for Lahontan cutthroat trout and the endangered cui-ui fish. To help mitigate the problem, Stampede Dam and Reservoir were built in 1970. The water stored in Stampede must be used primarily for spawning flows for the cui-ui fish species and the threatened cutthroat trout of Pyramid Lake.
It is sheer hubris to think that in our erratic Western climate, which swings between desiccating drought and heavy, wet winters, Lake Tahoe can be kept in perfect equilibrium to satisfy all users. History has proven otherwise. Long-term droughts have dropped the lake well below the natural rim, rendering the reservoir useless for extended periods of time, while powerful storms and rain-on-snow flood events have forced the release of Tahoe water and aggravated existing flood conditions. Indicative of our region’s climatic volatility, 20 major floods have occurred on the Truckee River in the last 150 years.