Related Links April 2008 Water Supply Outlook Letter from the Governor (PDF file, 1.22 MB) July 2007 Water Supply Outlook MWD Water Surplus and Drought Management Plan Report (January 7, 2008) (Powerpoint file, 411 K) WATER CONDITIONS: Tight Supply from Colorado River Could Hike Water Rates Memorandum: Colorado River Board of California (Word document, 39K)

WATER SUPPLY OUTLOOK UPDATE FOR JULY 2007

Statewide Conditions

The following reflects accumulated precipitation as of May 6, 2007.  May marks the end of the rainy season.  Please note that the accumulated precipitation for both the 8-Station index and Colorado River Basin reflect snowpack since it is much more indicative of the supply picture. 

Currently, Lake Oroville is 77% full which is 88% of average for this time of the year.  Lake Oroville can hold 3.54 MAF.  San Luis is 22% full which is 36% of average for this time of the year.  San Luis can hold 2.04 MAF with 60% of the capacity being the State's and 40% belonging to the CVP.  Diamond Valley Lake is 90% full which is 116% of average for this time of year.  Diamond Valley holds about 800,000 AF.

It's the 8th driest year on the Colorado River.  Lake Mead is at 1113 feet elevation or 12,679,000 AF and Lake Powell is at 3610 feet elevation or 12,764,000 AF.

Historic dry conditions have also been seen in southern California.

Metropolitan Supplies and Demands

Metropolitan current demand trends are 2.47 MAF.  Metropolitan has stopped delivering water for replenishment purposes effective May 1, 2007 to reduce demands. 

Core supplies are 2.16 MAF.  Colorado River supplies are 691,000 AF of these supplies which includes underuse of water from agricultural agencies.  The State Water Project allocation remains at 60%.  Based on this allocation plus carryover Metropolitan maintained in San Luis Reservoir and article 21 water, Metropolitan has about 1.5 MAF of SWP water.  About 270,000 AF of these supplies are at risk due to Delta pumping constraints that will be discussed later in this paper.

The balance of supplies to meet demands will be made up through WSDM actions.  These actions include pulling from Central Valley storage programs, increased conservation outreach, withdrawing from surface storage, interrupting replenishment and pulling from in-basin groundwater storage programs.

Looking at calendar year 2008, Metropolitan has projected that it will have a supply shortfall of about 400,000 AF.  This is based on the following assumptions:

• Demands remain the same
• Record dry conditions continuing
• Replenishment deliveries continue to be cut
• 30% IAWP delivery cuts
• Colorado River core supplies are delivered
• SWP supplies with pump restrictions equal a 30% allocation
• Metropolitan is able to provide some supplies through WSDM actions of calling dry year storage

Metropolitan will try to meet this shortfall through increased conservation outreach.  However, it has begun to prepare a drought allocation plan should it be needed.  It is also anticipated that should all assumptions remain the same, Metropolitan could pull from storage for the next three years and would then have emptied its storage accounts.

Delta Pumps Discussion

Over the last few years, the Delta smelt population has continued to decline.  Lawsuits have been filed by environmental organizations to stop the pumping at Banks Pumping Plant.  On April 18, 2007, an Alameda County Superior Court reaffirmed his decision that DWR must stop pumping water out of the Bay-Delta within 60 days unless it complies with environmental laws protecting fish.  The court has found that DWR is illegally killing threatened or endangered fish through operation of the State Water Project.  The State filed an appeal to the decision on May 7, 2007.  This appeal allows for a stay in the judge's decision.  On May 25, 2007, a federal judge ruled that the biological opinion regarding Delta smelt and Delta pumping is inadequate.

Then from May 25 through May 31, 2007 the state found over 200 Delta smelt entrained in the Banks Pumping Plant.  The State stopped pumping from the Delta from May 31 through June 9, 2007.  On June 10, 2007, DWR resumed limited pumping at Banks of 100 cfs.  (The capacity of the pumps is 6680 cfs.)  On June 17, 2007, pumping was increased to 1000 cfs and on June 22, 2007 pumping was increased to 2260 cfs.  DWR was to present its operating plan to the federal judge in early July and plaintiffs in mid-July.  The federal judge is scheduled to hear the case August 21, 2007.  The deadline for the new biological opinion is April 2008.

Metropolitan along with other State Water Contractors and the state are studying near term fixes to the Delta.  Additionally, without fixes, current studies are showing that under same drought conditions as 2007, the SWP allocation could be reduced from 25% (Pelagic Fish Action Plan, moderate case scenario) to 50% (Moyle-Swanson report, severe case scenario).

Indications are that pumping will be reduced by some amount to protect the Delta smelt.  How much will not be known until after the federal opinion expected August 21, 2007.

In light of supply issues the Interim Agricultural Water Program deliveries is scheduled to be curtailed by 30% beginning January 1, 2008.

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