California Water Service Company - Bayshore District, San Mateo System
San Mateo and the Cal Water Bayshore District
Population reference
102,348
Billing detail
Partial 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
- CPU C-regulated monthly service charge plus increasing block residential consumption tiers. Effective July 1, 2026 for the Bay Area Region residential metered schedule, a 5/8 x 3/4-inch meter has a $34.47 monthly service charge; usage is $4.2083 per CCF for 1-6 CCF, $16.8152 for 7-9 CCF, $21.0842 for 10-13 CCF and $25.2184 above 13 CCF. One CCF is approximately 748 gallons. San Mateo customers may also see a 1.350% San Mateo business-license surcharge and CPUC-approved surcharges or credits.
- Residential cost reference
- For a typical 5,000-gallon San Mateo account, approximately $71.22 for Cal Water service before taxes, CPUC surcharges and any separate local wastewater bill: $34.47 monthly service charge plus roughly $36.75 for 6.684 CCF under the July 1, 2026 BAR-1-R tiers. The calculation is an estimate because Cal Water bills in CCF and the applicable tariff components may vary by account.
- Wastewater and sewer calculation
- Cal Water's Bayshore District supplies drinking water; the reviewed official tariff and district pages do not establish a universal San Mateo wastewater formula. Sewer charges, if applicable, are generally administered by the local wastewater agency rather than included in the Cal Water water tariff; customers should verify the separate sewer statement and winter-averaging rules with the responsible local agency.
Context, not a score
How documentation coverage compares
This profile
43%
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
Partial public detail found
3 of 7 fields in this section contain provider-specific public detail in dataset August 1, 2026.
Documented
43%
Details not confirmed in the reviewed public material
- Billing frequency
- 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
- California Water Service Company - Bayshore District, San Mateo System public website ↗
Provider-controlled destination used to confirm current customer instructions.
- EPA Safe Drinking Water Information System ↗
Federal background on public water-system records and their limitations.