Limestone tuff formations at Mono Lake

by Christiane Schulze

Copyright: Christiane Schulze
Mono Lake is a soda lake; that is, it is both particularly alkaline and particularly saline. It is located in Mono County in the central-eastern part of California, in a drainageless basin at the western edge of the Great Basin below the eastern flank of the Sierra Nevada. Because of the harsh environmental conditions, animals and plants must be both adapted to the high pH and able to tolerate the salinity. Therefore, an ecosystem of very few adapted species with very high numbers of individuals has developed, which is of particular importance for some bird species.

Since 1941, drinking water has been discharged from the lake's catchment area into a water pipeline over 520 km long that supplies the city of Los Angeles. As a result, the lake's water level dropped continuously, salinity increased, and parts of the lakebed dried out. This had serious ecological consequences for the tributaries and the lake. At the same time, numerous underwater limestone tuff formations in bizarre shapes became visible in the lake and on the shore, which contributed to the lake's fame. Conservationists raised the issue of the lowering of the water level from the early 1980s. After court decisions to limit the discharge, it has been slowly rising again since the mid-1990s.