Starting in 1941 the streams that fed Mono Lake were diverted for use by the city of Los Angeles. With a yearly evaporation rate of 45 inches (nearly four feet) the lake level quickly dropped, going from an elevation of
Starting in 1941 the streams that fed Mono Lake were diverted for use by the city of Los Angeles. With a yearly evaporation rate of 45 inches (nearly four feet) the lake level quickly dropped, going from an elevation of 6,417 feet above sea level to a low point of 6,372 feet above sea level. The accompanying 31% loss of surface area and 50% loss of water volume had a devastating effect on the estimated two million birds that used the lake each year, as well as causing air quality problems due to the dust from the now-exposed lakebed. In 1994 a court ordered that the lake be returned to a level of 6,392 feet above sea level, but due to droughts in the region the current (2008) level is still only 6,382 feet above sea level.
The lake is believed to have formed 760,000 years ago, although it may be a remnant of a larger lake that formed 1-3 million years ago, thus making it one of the oldest lakes in North A