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BOARD MEMORANDUM

DATE: June 14, 2018
TO: Board of Directors

FROM: Dirk Marks
Director of Water Resources
SUBJECT: Approve a Resolution Determining that 489 Acre-Feet Per Year of Buena Vista-
Rosedale Rio Bravo Water Supply is Available for Possible Use for the
Proposed Tapia Annexation

SUMMARY

On November 13, 2017, the Castaic Lake Water Agency (CLWA) executed the Deposit and
Funding Agreement for the Tapia Ranch (Vesting Tentative Tract Map 72126 (Annexation
Property). The annexing party is Debt Acquisition Company of America (DACA). As provided in
the Deposit and Funding Agreement, DACA has requested that the SCV Water Board of
Directors, as successor to CLWA, consider and make a determination that Buena
Vista/Rosedale Rio Bravo (BVRRB) water is available for the proposed annexation property.
Staff has completed a water demand analysis for the proposed annexation property, reviewed
the Agency’s 2015 Urban Water Management Plan (UWMP) and the 2017 Water Supply
Reliability Report Update and concluded that given current planning assumptions, sufficient
supplies are adequate to make such a determination. Under the terms of the Deposit and
Funding Agreement, DACA will be required to pay for past acquisition and carrying cost for the
BVRRB water totaling $3,775,117, as well as pay ongoing carrying costs.

BACKGROUND AND DISCUSSION

In October 2006, CLWA certified the Final EIR Water Acquisition from the Buena Vista Water
Storage District and the Rosedale-Rio Bravo Water Storage District Water Banking and
Recovery Program. The EIR estimated that 4,375 acre-feet per year (AFY) of the 11,000 AFY
BVRRB water would be available to annexations with an estimated 750 AFY going to the Tapia
project. In 2007, potential annexing parties were informed that because of more restrictive
Sacramento-San Joaquin Delta regulatory measures, the Agency would not make BVRRB
water available at that time. Subsequent analysis, including the 2010 Urban Water Management
Plan (UWMP), incorporated higher water conservation requirements.

Revised population and development information consistent with the One-Valley-One-Vision
general plan were incorporated into the 2015 UWMP allowing for a reexamination of the
availability of BVRRB water to meet annexation requirements. Consistent with the Agency’s
Annexation Policy, staff has undertaken an analysis to determine the demand for the currently
proposed Annexation Property. That determination is made considering the landowner’s plan to
develop the property. Staff’s determination of the demand is 489 AFY. This demand assumes
that those areas outside of the designated residential development, as shown on Figure 1, are
permanently dedicated open space not available for further development and will not result in
additional water demand. Additionally, the 489 AFY is less than the 575 AFY that was included
in the 2015 UWMP. Further, the demands for the proposed Tesoro annexation have recently

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