Title
Adopt a release schedule for Nacimiento and San Antonio reservoirs for 2024.
(Staff: Peter Kwiek & Joseph Klein)
Report
RECOMMENDATION:
It is recommended that the Monterey County Water Resources Agency Board of Directors:
Adopt a Release Schedule for Nacimiento and San Antonio Reservoirs for 2024.
SUMMARY/DISCUSSION:
Each spring, the Agency proposes an annual reservoir release schedule based on a variety of factors that include current reservoir storage, river flows, Nacimiento Water Project water orders, and implementation of the Salinas Valley Water Project.
The attached proposed 2024 schedule assumes continuous conservation flows to recharge the Salinas Valley groundwater basin and operate the SRDF from late April to mid-October and meets the operational requirements of State Water Resources Control Board appropriative water rights held by the Agency for the Nacimiento and San Antonio Rivers.
Following a full conservation season which provided groundwater recharge and SRDF diversions from May through October, 2023, numerous small to moderate winter storms have re-filled the Nacimiento Conservation Pool and brought San Antonio close to its operational volume limit which is currently based on the 1985 Rule Curve pending re-construction of the San Antonio Dam Spillway. As a result, total combined reservoir storage volume in early April exceeds 600,000 acre feet for the first time since 2011.
As a result of late season (late March to Early April 2024) inflow to Nacimiento Reservoir and significant flows within the Salinas River, commencement of conservation releases and SRDF operation are being delayed. This will also allow time for a sufficient volume of water to be evacuated from the reservoir to enable scheduled critical spillway maintenance to begin in early June with minimal disruption to operations later in the season. This release of water is reflected in the schedule’s April release totals and is expected to be completed by about April 22. Conservation releases are expected to begin thereafter, and SRDF diversions will start once the lower Salinas River flows are sufficiently decreased and turbidity is acceptably low, in support of safe operations.
The proposed 2024 release schedule accounts for current and near-term reservoir inflow rates but assumes no new inflow events for the remainder of the calendar year. The schedule also accounts for estimated flow requirements stipulated in the Flow Prescription and incorporated into Agency water rights. Temporary release adjustments to accommodate recreation activities over holiday periods are also incorporated into the proposed schedule.
As is the standard procedure each year, the release schedule will be updated monthly based on actual hydrologic conditions, changing SRDF demands, and other reservoir operational considerations as may be necessary subsequent to the development of this initial release schedule.
OTHER AGENCY INVOLVEMENT:
On April 4, 2024, the Reservoir Operations Advisory Committee recommended adoption of the proposed release schedule by the Board of Directors.
FINANCING:
None
Prepared by: Peter Kwiek, Associate Water Resources Hydrologist (831) 755-4860
Joseph Klein, Water Resources Hydrologist (831) 755-4860
Approved by: Ara Azhderian, General Manager (831)755-4860
Attachments:
1. Reservoir Release Schedule For 2024
2. Board Order