Lake Tahoe is the largest "alpine" lake in the U.S. at an elevation of 6225 feet above sea level. It is 1645 feet deep at its deepest point, second only to Crater Lake in the U.S. About half its water comes from 63 streams flowing from the surrounding mountains, the other half resulting from rain and snow. Its only outlet is the Truckee River, controlled by a dam to prevent flooding.
The area around the lake is mostly national forest and state parks, preserving the scenic beauty and recreational opportunities for public use. Still, there is significant private land that has become some of the most prized real estate in the country.
Not far south of Lake Tahoe is a much different kind of lake. Mono Lake was formed about 800,000 years ago by several streams flowing out of the Sierras, bringing a variety of minerals into the Mono Basin. Since the lake has no outlet, evaporation caused the minerals to accumulate, resulting in highly alkaline water with a high content of dissolved carbon. Underground springs entering the lake have high levels of calcium that reacted with the carbonated water of the lake. The result was formation of calcium carbonate, a form of limestone called tufa.
These formations remained under water until the Los Angeles Water Department entered the picture. In desperate need of water for its rapidly increasing population, the city began buying up property that included most of the water rights in the area. This was done without revealing the purpose. Once all the necessary properties were acquired, a canal was built to move the water to LA, depriving Mono Lake and Owens Lake of most water sources. Lake levels began to drop and mineral content increased dramatically. Years of lawsuits followed and limits were finally imposed on how much water could be diverted However, Mono Lake is today much lower than historic levels, allowing the tufa spires to be seen on land and in the lake itself.
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