ITEM:

CONSENT CALENDAR

 

5.

RECEIVE WATER SUPPLY FORECAST FOR PERIOD OF MAY 1, 2005 THROUGH SEPTEMBER 30, 2006

 

Meeting Date:

May 16, 2005

Budgeted: 

N/A

 

From:

David A. Berger,

Program/

N/A

 

General Manager

Line Item No.:

 

Prepared By:

Darby Fuerst

 Cost Estimate: 

N/A

 

General Counsel Approval:  N/A

Committee Recommendation:  N/A

CEQA Compliance:  N/A

 

SUMMARY:  Regulation X of the Monterey Peninsula Water Management District (District) Rules and Regulations requires that a water supply summary forecast report be compiled annually to analyze the status of water supply and demand within the District.  This report quantifies rainfall, runoff, and storage conditions within the District as of May 1, 2005, and forecasts the amount of water that will be available for the upcoming water year.  This item is for informational purposes only; no Board action is required at this time. 

 

Physical Water Availability:  As of May 1, 2005, usable water storage within the Monterey Peninsula Water Resources System (MPWRS) totaled 32,400 acre-feet or 86% of maximum storage capacity.  A map of the MPWRS is included as Exhibit 5-A.  A breakdown of total storage by reservoir and aquifer is shown in Exhibit 5-B.  As shown, usable reservoir storage totals 1,550 acre-feet and usable aquifer storage totaled 30,850 acre-feet.  In addition, a summary of other water-supply related conditions within the MPWRS -- rainfall, runoff, and number of adult steelhead recorded at San Clemente Dam, and Cal-Am monthly diversions from the Carmel River and Seaside Ground Water Basins relative to limits set by the State Water Resources Control Board (SWRCB) and District -- are shown in Exhibit 5-C and 5-D.

 

The amount of carryover storage that is needed to meet the projected water needs within the District for the remainder of Water Year (WY) 2005 and all of WY 2006 is shown in Exhibit 5-E.  These projections include the water needs of both Cal-Am customers and non-Cal-Am water users within the District who rely on water from the MPWRS.  As shown, the projected water demand for the remainder of WY 2005 is 9,472 acre-feet.  Similarly, the projected demand for WY 2005 is 17,980 acre-feet. This projection is based on the maximum annual production amount for Cal-Am from the Carmel River Basin directed by the SWRCB in Order No. WR 95-10 (11,285 acre-feet), the maximum annual production amount for Cal-Am from the coastal subareas of the Seaside Groundwater Basin specified by the District in the Quarterly Water Supply Strategy and Budget process (4,000 acre-feet), and the production that was reported for non Cal-Am users in the MPWRS in WY 2004 (2,695 acre-feet).

 

As shown in Exhibit 5-E, the total amount of water needed to meet the projected water demand for the remainder of WY 2005 and all of WY 2006 is 27,452 acre-feet.  Given the current usable storage estimate of 32,400 acre-feet, there is sufficient stored water in the MPWRS to meet the projected water needs for the remainder of WY 2005 and begin WY 2006 with a full year’s


supply in reserve.  This is consistent with the District drought protection goal approved by the Board in August 1993.

 

It should also be noted that this approach is conservative in that it is based entirely on storage and does not include any allowance for surface and subsurface inflows that are expected to occur.  Therefore, based on the physical availability of water, no additional water demand reductions are required at this time.  It should be noted, however, that this analysis does not incorporate environmental considerations such as effects on riparian and aquatic resources, which are outside of the scope of this physical availability analysis.

 

Community Water Demand:   For WY 2005, as of May 1, 2005, Cal-Am had produced 6,594 acre-feet of water from its sources in the MPWRS to serve customers in its main system. This amount of production is 990 acre-feet under the year-to-date at month-end production target (7,584 acre-feet) that had been set for Cal-Am’s main system based on SWRCB Order 95-10 and the District Quarterly Water Supply Strategy and Budget process.  Specifically, Cal-Am’s year-to-date production from the Carmel River Basin was 5,634 acre-feet or 428 acre-feet less than the year-to-date production target of 6,062 acre-feet.  Similarly, Cal-Am’s year-to-date production from the coastal subareas of the Seaside Groundwater Basin was 960 acre-feet or 562 acre-feet less than the year-to-date production target of 1,522 acre-feet.  This amount of reduced production, relative to projected water demand, is consistent with the amount of usable water storage that is available in the MPWRS at this time and reflects the above normal rainfall and runoff conditions that occurred during the first seven months of WY 2005.  Therefore, based on current and expected water demand by customers in Cal-Am’s main system, no additional water restrictions are needed at this time.  All water users within the District are encouraged to conserve water.

 

Seaside Groundwater Basin Yield:   It should be noted that this forecast is based on an assumption that Cal-Am can produce up to 15,285 acre-feet each year from its sources in the MPWRS to serve the customers in its main system.  This limit is based on the maximum that Cal-Am is allowed to produce from the Carmel River Basin (11,285 acre-feet per year) under SWRCB Order 95-10 and the maximum that Cal-Am has been allowed to produce from the coastal subareas of the Seaside Groundwater Basin (4,000 acre-feet) in the Quarterly Water Supply Strategies and Budgets developed by District and Cal-Am staff.  Based on recent updates regarding the Seaside Groundwater Basin and existing overdraft conditions, the maximum amount that Cal-Am can continue to produce from the coastal subareas of the Seaside Groundwater Basin will need to be addressed in future water supply budgets and forecasts.    

 

RECOMMENDATION:   The Board should receive the water supply forecast for the May 1, 2005 through September 30, 2006 period. 

 

IMPACTS ON STAFF/RESOURCES:  District staff currently tracks and reports on water production and water supply conditions on a monthly basis; no additional impacts are anticipated related to this item.

 

EXHIBITS

5-A      Map of the MPWRS

5-B      MPWRS Water Storage Conditions

5-C      MPWMD Water Supply Status -- May 1, 2005

5-D      Monthly Cal-Am Diversions from Carmel River and Seaside Ground Water Basins

5-E      Derivation of Water Rationing Triggers for the MPWRS for WY 2005

 

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