Mono Lake Level
and tributary streamflows
MONO BASIN STREAMFLOWS
MONO LAKE LEVEL
||approx. future management level
||highest level reached since 1994
|10/1/2019 (1 year ago)
|9/1/2020 (1 month ago)
|trigger: April 1st export restriction
||trigger: minimum level
||9/28/1994 (D-1631 was issued)
||Lowest level (1/1/1982)
Monthly Levels since 1979
Yearly Levels since 1850
Water Board Decision Background
The Mono Lake Committee's June 3, 2020 Mono Lake projection (PDF with details):
The Mono Lake Committee's June 3, 2020 Mono Lake projection (image):
Mono Lake rises in wet summers and years and falls in dry summers and years. It also tends to rise in the winter and spring, and declines in autumn.
How is Mono Lake's level measured?
The lake level gauge is a staff gauge located near Old Marina that is demarcated in tenths and hundredths of a foot. DWP surveys the elevation of the gauge each time it installs one. The Mono Lake Committee reads it at least once a month. DWP reads it approximately weekly.
- 5/23/14 gauge 1S installed with a zero elevation of 6377.79 USGS.
- 9/23/09 gauge 1R adjusted and surveyed about a mile east of Old Marina and all other gauges at this location removed. Zero elevation is 6379.997 feet above sea level USGS. Underwater as of July 2011 and on dry land as of July 2014.
- Old Marina Gauge 2A installed March 14, 2007, resurveyed 8/1/07, zero elevation 6382.06 USGS. Mono Lake dropped below zero on this gauge in August 2009 and the staff plate was removed in September. In 2011 the staff plate was reinstalled and the new zero elevation was 6382.059.
- Installed July 13, 1998 (1M), zero elevation of 6,383.82 (in 2007 revised to 6383.76) USGS
- Installed June 25, 2001 (1N), zero elevation of 6382.01 USGS (lake elev. Dec. 2005) Note: Gauge 1N read 0.07 feet too low prior to its January 2007 removal.
- Installed August 12, 2002 (1P), zero elevation of 6380.37 USGS Note: Discontinued in late January 2007, perhaps read 0.1 feet too high immediately prior. As of August 2009 reads about 0.5 feet too high.