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- Reclamation Announces May Update to Central Valley Project Water Supply Allocations
News Release Archive
Reclamation Announces May Update to Central Valley Project Water Supply Allocations
Media Contact:
Pete Lucero, 916-978-5101, 05/22/2009 14:49
For Release: May 22, 2009
The Bureau of Reclamation today announced increases in allocations for certain Federal Central Valley Project (CVP) water service contractors and the potential for increases for water service contractors south of the Delta. This water supply update is based on the latest runoff forecast from the California Department of Water Resources (DWR). The final snow survey of the 2008-2009 season on April 30, 2009, indicated that the snowpack water content was 66 percent of normal Statewide. Federal CVP reservoirs currently average 62 percent of capacity, with Folsom Reservoir at 96 percent, Shasta Reservoir at 70 percent, and the Federal share of San Luis Reservoir at only 29 percent; however, above-normal precipitation in early May has resulted in a small increase in available water supplies.
Despite these increases for some contractors, difficult conditions remain in California's Central Valley as a result of a third consecutive dry year, continued restrictions on CVP operations to protect threatened and endangered fish species, and requirements to meet water right permit terms and conditions. Reclamation is concerned about the significant economic hardship created by water supply shortages throughout the CVP service area, particularly for water service contractors south of the Delta, and continues to work with water contractors, State and Federal agencies, and others to make the most effective use of the limited water supplies.
This month, Reclamation prepared a single forecast based on a 90-percent chance of having runoff equal to or greater than forecasted (90-percent probability of exceedence). Reclamation traditionally expresses the monthly forecast as a percentage of the contract total for each of the contract categories (see summary table). The allocation to water service contractors south of the Delta remains officially at 10 percent; however, improved hydrologic conditions create a possible 5 to 10 percent supply increase if additional pumping capacity can be made available through the summer. Reclamation is working closely with DWR to coordinate operations to help convey CVP supplies. Recognizing the critical conditions for many growers south of the Delta, Reclamation will announce any increase to allocations as soon as these supplies are secure.
| Probability of Exceedence Forecasts | | North of Delta Allocation | South of Delta Allocation | ||||||
| Ag | M&I | R | WR | Ag | M&I | R | WR | ||
| 90% Forecast | 61% / Dry | 40% | 75% to 100% | 100% | 100% | 10% | 60% | 100% | 100% |
In the 90-percent exceedence runoff forecast, the unimpaired water year inflow into Shasta Reservoir is estimated at 4.05 million acre-feet. The Sacramento Valley Index is a calculated estimate of the unimpaired runoff from the Sacramento River and its major tributaries and is used to determine the water year type, which is considered dry.
Given the projected American River runoff and Folsom Reservoir storage, the American River Division M&I contractors are allowed delivery up to their full contract quantity (100 percent) within the terms of their individual contracts. North of the Delta M&I contractors who receive their supply from the Sacramento River will receive 75 percent of historic deliveries. The allocation shown in the table for M&I contractors south of the Delta may be adjusted to meet heath and safety needs.
The 100-percent allocation shown in the table for Refuges applies to Level 2 supplies only and makes up about three-fourths of the Refuge's annual needs.
The allocation for CVP Eastside Division (Stanislaus River) contractors is unchanged at 18,000 acre-feet.
The Friant Division deliveries for Water Year 2009 are projected to be about 1,050,000 acre-feet, which is 84 percent of the Recent 5-Year Average Allocation of 1,250,000 acre-feet. The allocation for the Friant Division Contractors is based on DWR's 50-percent probability of exceedence forecast dated May 12, 2009. If the San Joaquin River natural runoff develops as expected, the Friant Division will receive 100-percent Class 1 water (firm supply of 800,000 acre-feet) and 18-percent Uncontrolled Class 2 water (less-firm supply estimated to be 250,000 acre-feet).
Reclamation is working closely with the State of California under the Reclamation States Emergency Drought Relief Act of 1991 to facilitate water transfers through the State's Drought Water Bank and to provide technical expertise related to water management. Reclamation is exploring every option available under our legal authorities and California water law to help relieve drought impacts on CVP water users, to provide any available operational flexibility to convey and store water, to facilitate additional transfers and exchanges, and to expedite any related environmental review and compliance actions.
In the coming months, updates to this forecast will be announced as circumstances warrant. Information is posted on the Region's website at http://www.usbr.gov/mp. Please contact the Public Affairs Office at 916-978-5100 or e-mail ibr2mprpao@mp.usbr.gov for additional information.
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The Bureau of Reclamation is a federal agency under the U.S. Department of the Interior and is the nation's largest wholesale water supplier and second largest producer of hydroelectric power. Our facilities also provide substantial flood control, recreation opportunities, and environmental benefits. Visit our website at https://www.usbr.gov and follow us on Twitter @USBR; Facebook @bureau.of.reclamation; LinkedIn @Bureau of Reclamation; Instagram @bureau_of_reclamation; and YouTube @reclamation.
