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CITY OF LOS ANGELES CONSERVATION ELEMENT
Adopted September 2001
II-41
acquisition and maintenance, salt cedar plant nuisance abatement and
for county water department environmental programs.
Mono Lake. In 1940 the DWP extended its aqueduct system to Mono Basin,
diverting snow melt waters from Lee Vining, Walker, Parker and Rush
creeks, the main sources that feed Mono Lake. The 65 square mile salty,
alkaline lake lies 6,000 feet above sea level in the high desert of the
eastern Sierra, below the Tioga Pass entry to Yosemite National Park.
More than 250,000 people a year from all over the world arrive by road,
foot or on skis to enjoy the eerie volcanic beauty and magnificent
views. The lake is believed to be a million year old remnant of an
inland sea. Minerals carried by waters that flow through volcanic and
geologic formations maintain the high saline content of the lake, which
provides a unique ecosystem that supports millions of rare brine shrimp
and other organisms. The organisms provide food for migratory birds and
are harvested commercially. Two large volcanic islands (Paoha and
Negit) provide migratory stop-over and nesting sites for thousands of
ocean feeding birds, including phalaropes, which arrive in midsummer on
their way from the arctic to nesting grounds in Baja, California. An
estimated 90% (50,000 birds) of the California and 20% of the world sea
gull population nest on the islands.
Diversion by the DWP of as much as 95,000 acre feet of water annually,
along with Owens Valley resources, provides Los Angeles with its least
expensive and purest sources of water. But diversion has severely
impacted the Mono Basin, causing the lake to drop as much as 40 feet
since 1941. The drop exposed 21 square miles of lake bed. This resulted
in a doubling of the water's salinity (three times saltier than the
ocean) and left a residue of dry salt and mineral crystals, similar to
that of Owens Lake, that was stirred into dust clouds by high winds.
In the late 1970s, continued low snowfall in the eastern Sierra,
combined with the DWP's diversion of stream water caused the level of
the lake to drop significantly, exposing land bridges to Negit Island.
Coyotes traversed the exposed land, destroying a colony of nesting
gulls (1978). The Audubon Society and the Mono Lake Committee
petitioned the court to prohibit the diversion of creek waters,
contending it was causing irreversible ecological damage.
Heavy snowfall during the winters of 1983 and 1984 led to another court
action. The abundant snow melt following the heavy snowfalls caused the
two DWP dams to overflow, sending water and trout down the dry stream
beds that fed the lake. When the DWP resumed its stream diversion,
California Trout, Inc., a sport fishing organization, and the Mono Lake
Committee filed suit requesting enforcement of a state fisheries law
that prohibits killing of fisheries to supply water to an aqueduct.
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CITY OF LOS ANGELES CONSERVATION ELEMENT
Adopted September 2001
II-42
After a decade of litigation and negotiation,
the state Water Resources
Control Board (1994) issued Decision No. 1631, which establishes a
schedule of stream flows; fixes the amount of water the DWP can divert
from the basin, based on the elevation of the lake; and requires
preparation of a stream and waterfowl habitat restoration plan.
Following a settlement agreement between Los Angeles and interested
parties concerning the monitoring program, the board (1998) approved
the stream and waterfowl habitat plan.
The plan permits the DWP to export 16,000 acre feet of water a year
from the basin. This figure will increase to 30,000 acre feet per year
when Mono Lake reaches an elevation of 6,391 feet. The lake had risen
to 6,385 feet by 2000, sufficiently covering the land bridges between
Negit Island to ward off coyotes. It is anticipated that it will take
approximately 20 years for the 6,391 level to be achieved.
To assist Los Angeles in replacing aqueduct water due to the reduced
diversion, the state legislature (1994) approved a bill allocating $36
million for water projects in Los Angeles, primarily for the East
Valley Reclamation Project in the San Fernando Valley. The East Valley
Project will provide an estimated one-third of the amount of Mono Lake
water lost as a result of the settlement. The DWP will supply remaining
water needs by purchase and from other sources.
Conclusion. The city is responsible, in whole or in part, for
management of facilities and properties it owns or operates outside its
borders. Its stewardship includes consideration of potential impacts on
and management of natural areas and scenic resources.
Continuing issues:
N
Meeting the city's water, power and other needs while at the same
time striving to be a good steward of natural
resources and to minimize
impacts on the environment.
N
Compliance with environmental protection legal agreements involving
City owned or operated facilities which are located beyond the city's
borders.
Habitats and scenic areas outside the city objective, policies and
programs:
Objective: protect important natural habitats and scenic sites outside
the city which are owned by the city or are impacted by city
facilities.