Sonoma County Water Agency (Sonoma Water)
Sonoma and Marin Counties through Sonoma Water’s wholesale transmission system and its eight primary retail water contractors
Population reference
More than 600,000 residents in Sonoma and Marin Counties through wholesale domestic-water supply and delivery; active CWS PWS CA4910020 is listed by California Drinking Water Watch as Sonoma County Water Agency.
Billing detail
Limited public detail found
Official destination
Open provider website ↗Provider-specific findings
Billing and account research from public material
Provider-specific research notes are displayed separately from fields that contain only an unavailable-information marker. Read qualifiers in each note and verify current account terms with the provider.
- Rate structure
- Wholesale water-transmission rate structure based on aqueduct/contractor service, water-supply operations, infrastructure, debt service, and fixed meter or capacity charges. The FY2026–27 Board action states that rates must cover projected operation, maintenance, infrastructure, and debt-service requirements. The published wholesale rate is passed through in varying ways by the eight retail contractors and is not a residential tier schedule.
Context, not a score
How documentation coverage compares
This profile
14%
overview fields with research notes
California
67%
records with any overview detail
National index
50%
records with any overview detail
Coverage measures what this directory documented. It does not measure service quality, affordability, or regulatory compliance.
Research record
Limited public detail found
1 of 7 fields in this section contain provider-specific public detail in dataset August 1, 2026.
Documented
14%
Details not confirmed in the reviewed public material
- Billing frequency
- Residential cost reference
- Wastewater and sewer calculation
- Meter reading
- New-account deposit
- Activation or transfer fee
“Not confirmed” means the directory did not identify a dependable public statement. It does not mean the provider has no policy or option.
Primary verification routes
- Sonoma County Water Agency (Sonoma Water) public website ↗
Provider-controlled destination used to confirm current customer instructions.
- csd.ca.gov reference ↗
Public URL preserved in the compiled record. Confirm its publisher, date, and applicability before relying on it.
- EPA SDWIS / ECHO lookup (CA4910020) ↗
Search the federal drinking-water database using public water system ID CA4910020.