October 2023 Temporary Urgency Change Petition
On October 12, 2023, Sonoma Water filed temporary urgency change petitions (TUCPs) with the State Water Resources Control Board Division of Water Rights. These petitions were submitted to temporarily modify the permit terms that establish the hydrologic conditions for setting the minimum instream flow requirements. The hydrologic index for the Russian River was established by Decision 1610 in 1986 for Permits 12947A, 12949, 12950 and 16596. In response to changed watershed conditions due to recent operational changes of PG&E's Potter Valley Project, these modifications are necessary to align the hydrologic index designations with actual watershed conditions.
Minimum in-stream flow background:
Sonoma Water controls and coordinates water supply releases from Lake Mendocino and Lake Sonoma to implement the minimum instream flow requirements in water rights Decision 1610, which the State Water Resources Control Board adopted in 1986. Decision 1610 specifies minimum flow requirements for the Upper Russian River, Dry Creek, and the Lower Russian River. These minimum flow requirements vary based on water supply conditions, which are also specified in Decision 1610. The Decision 1610 requirements for the Upper Russian River and Lower Russian River are contained in term 20 of the Water Agency’s water-right Permit 12947A (Application 12919A). The Decision 1610 requirements for the Lower Russian River are contained in term 17 of the Water Agency’s water-right Permit 12949 (Application 15736) and term 17 of the Water Agency’s water-right Permit 12950 (Application 15737). The Decision 1610 requirements for Dry Creek and the Lower Russian River are contained in term 13 of the Water Agency’s water-right Permit 16596 (Application 19351).
Sonoma Water’s operations are also subject to the Russian River Biological Opinion issued by the National Marine Fisheries Service on September 24, 2008.
Additional Reports
View Weekly Hydrologic Reports of recent historical hydrologic conditions and forecasted rainfall for the Russian River watershed
View Water Accounting Reports with detailed analysis of reservoir operations and river flows in the Russian River watershed
View Russian River Water Quality Status Reports
More Information:
View TUCP Archive