The U.S. Bureau of Reclamation has agreed to contribute funding in the amount of $1,025,000 in fiscal year 2013 for a San Diego Watershed Basin Study proposed by the City of San Diego along with two other local agencies.

According to San Diego’s proposal, the study’s two primary objectives are:

1. Determine how climate change will impact the current and future water supply portfolio of the San Diego region.
2. Develop infrastructure options within the San Diego Basin that can serve as adaptation strategies to manage climate change impacts, focusing on optimizing the reservoir systems and furthering development of indirect potable reuse.

There are uncertainties associated with Northern California and Colorado River water (regulatory restrictions and dry conditions, respectively) upon which the San Diego region relies for 70-90% of its needs. While previous work has been done to address the potential gap between supply and demand from the above causes, the potential climate change effects were not taken into account. The proposed watershed basin study would analyze those effects.

The San Diego Public Utilities Department (PUD) is the project sponsor, with the San Diego County Water Authority (SDCWA) and the County of San Diego serving as partners.

The San Diego watershed basin study area is comprised of the six sub-hydrologic units (HU) within San Diego County highlighted above in blue. Click map to enlarge.

Budget: $1 million was requested from Reclamation, a grant of $782,244 was secured from the San Diego Integrated Regional Water Management (IRWM) Program, and $300,000 would be paid by PUD creating a project total of $2,082,244.

The San Diego IRWM Program, formed in 2005, has a vision for “[a]n integrated, balanced, and consensus-based approach to ensuring the long-term sustainability of the Region’s water supply, water quality, and natural resources.”

In addition to approving the requested $1 million, the Reclamation Bureau granted an additional $25,000. In its notification letter to the city, the Bureau said “…funding will be provided in two phases. First, $25,000 will be allocated for the development of a detailed Plan of Study… [and] Contingent upon Reclamation’s approval of the Plan of Study, $1,000,000 will be allocated for conducting the study.”

Work on the Plan of Study and a Memorandum of Agreement begins today at a kickoff meeting between the study partners and a representative from Reclamation. The Plan must be submitted for approval by September 30.

The new basin study might be able to consider aspects of a four-reservoir intertie project for which San Diego and Sweetwater Authority tried to execute a feasibility study in 2011 but were unsuccessful partly because, according to PUD Principal Water Resources Specialist Cathleen Pieroni, hoped-for funding from the Bureau of Reclamation fell through because the Bureau was unable to get an allocation from Congress did not appropriate the funding necessary to complete the Study that it authorized.

Tasks for the San Diego Watershed Basin Study include basin water supply and demand projections, climate change evaluation, development of adaptation strategies, and a trade-off analysis. The final report is expected to be ready in mid-2015.