Inyo County
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LADWP Pumping and Uses on the Bishop Cone

Each year, ICWD and LADWP conduct an audit of LADWP's groundwater extraction and water uses on Los Angeles land in the area surrounding Bishop commonly referred to as the "Bishop Cone." The Inyo/Los Angeles Water Agreement requires that, in any runoff year, LADWP's groundwater extraction may not exceed the amount of water used on its Bishop Cone lands. (A 1998 court decision may affect LADWP's pumping on the Cone.)

Runoff Year
(April 1 - March 31)
 Uses
(Acre-feet)
Groundwater Extractions
(Acre-feet)
1996-1997 25,098 14,421
1997-1998 22,751 15,541
1998-1999 21,825 10,073
1999-2000 23,661 16,227
2000-2001 21,498 15,560
2001-2002 22,514 15,818
2002-2003 25,180 15,779
2003-2004 21,698 16,803
2004-2005 22,416 16,371
2005-2006 24,060 12,181
2006-2007 21,262 11,090
2007-2008 21,419 15,472

The Water Agreement defines water uses as the amount of water supplied to Los Angeles land on the Bishop Cone less any return flow to the Los Angeles Aqueduct system. Uses include irrigation, stockwater, and recreation, as well as conveyance losses (i.e. water seepage from canals and ditches). Groundwater extraction is defined as the sum of all groundwater pumped by LADWP on the Bishop Cone plus the amount of artesian water that flowed out of uncapped wells on Los Angeles land on the Cone during the runoff year.

LADWP collects the pumping and surface water information at mutually agreed upon measuring stations and provides that data to the county. ICWD performs the audit and reports on the water uses and groundwater extractions on the Bishop Cone. The table above shows the results of Bishop Cone audits performed to date.

The final 2008-2009 Bishop Cone Audit is expected to be completed by the end of 2009.  The 2007-2008 Bishop Cone Audit is available as part of the DWP 2009-2010 Annual Operations Plan - May 2009.