Water Use Efficiency


Planning for a Water-Secure Future


Water Shortage Assessment Report

Starting July 1, 2022, water suppliers in California are required (California Water Code §10632.1) to do an annual assessment of their water supply and demand. This assessment is called the Annual Water Supply and Demand Assessment (AWSDA). The AWSDA helps water suppliers assess how reliable their water supply will be for the current year and the following assumed dry year. The AWSDA forecasts near-term water supply conditions to ensure shortage response actions are triggered in a timely manner. Every year, Sonoma Water evaluates water conditions from different sources and determines how much is needed for the current year, assuming the next year is dry. This assessment includes details and numbers for each water source.

View the 2024 Sonoma Water Water Shortage Assessment Report


Urban Water Management Plan

Sonoma Water is a wholesaler of potable water, serving nine primary municipal customers in Sonoma and Marin Counties. Sonoma Water updated its Urban Water Management Plan (UWMP) and Water Shortage Contingency Plan (WSCP) for 2020 in line with the Urban Water Management Planning Act (California Water Code §10608–10656). They did this with the help of community members and its retail water contractors. The plan is updated every five years.

Sonoma Water’s 2020 UWMP discusses and describes the following:

  • Existing water supplies and transmission system facilities;
  • Projected water demands in Sonoma Water’s service area over the next 25 years;
  • Projected water supplies available to Sonoma Water over the next 25 years, the reliability of that supply, and general schedules for water supply projects;
  • Climate change impacts the water supply;
  • Energy intensity;
  • Current and planned Sonoma Water water conservation activities;
  • An updated and separately adopted Water Shortage Contingency Plan (Appendix C); and 
  • A comparison of water supply and water demand over the next 25 years under different hydrological assumptions (normal year, single dry year, multiple dry years)

Urban Water Management Plan


Regional Water Conservation Programs

Sonoma Water is the lead agency of the Sonoma-Marin Saving Water Partnership - a regional collaboration providing water use efficiency programs to customers of local water utilities.

The utilities include the cities of Santa Rosa, Rohnert Park, Petaluma, Sonoma, Cotati, Healdsburg, and Cloverdale; the North Marin and Valley of the Moon Water Districts; the Town of Windsor; Marin Water; and California American Water—Larkfield and Sonoma Water.

The Sonoma-Marin Saving Water Partnership is a key water supply strategy to support regional water conservation and minimize impacts on constrained water supplies during the summer months and in times of severe drought. Since forming in 2009, the partnership has been effective at lowering water demands.





View the Sonoma-Marin Saving Water Partnership Annual Report