As part of a water rights application, the applicant is required by the California Water Code Section 1260(k) to perform a Water Availability Analysis (WAA), to include “sufficient information to demonstrate a reasonable likelihood that unappropriated water is available for appropriation.” In addition, before the State Water Resources Control Board (SWRCB) can grant a water rights permit, it must find that there is “unappropriated water available to supply the applicant” as outlined in Water Code Section 1375(d).
ECORP has a long and successful record of developing WAAs in support of SWRCB-compliant water rights applications for submittal as evidence to the SWRCB. Each WAA is tailored to best uphold project objectives and includes a detailed description of the quantities, rates, timing, and frequency of water requested from sources to meet demands, and a technical evaluation to determine if there is a reasonable likelihood that unappropriated water is available for appropriation sought under the application.
We use a variety of approaches and methods to evaluate unappropriated water within a watershed with special care in appraising water right priorities. We determine the impaired and unimpaired streamflow over a study period by evaluating effects resulting from higher priority direct diversion and storage water rights, and instream flow requirements. WAAs include an estimation of water supply available in differing water year types (wet, average, and dry). A comparison of supply and demand for the study period will be completed to verify that water is available under the application for appropriation.
If you have questions or would like to discuss a Water Availability Analysis, please contact Michael J. Preszler, California Water Practice Leader, at (916) 782-9100.