Private Investor-Owned Utility
California Water Service Company - Chico System
Serving Chico and Hamilton City, plus vicinity in Butte and Glenn Counties
Population served
114,925 people; 26,808 residential service connections, 3,566 commercial connections, and 22 industrial connections according to California Drinking Water Watch for active system CA0410002.
State system code
FIPS 06
Billing frequency
Generally monthly billing, with the bill showing the service period, meter read dates, current charges, due date, and prior balance. The exact read and due-date calendar is premise-specific.
Provider briefing
How this utility’s billing works
California Water Service Company - Chico System operates as a private investor-owned utility serving Chico and Hamilton City, plus vicinity in Butte and Glenn Counties. Customers should use the provider’s current account-specific bill and official customer-service instructions as the final authority for deadlines, balances, and service requests.
The published water-rate framework is described as CPUC-regulated metered increasing-block residential structure for the Chico tariff area: a fixed monthly service charge plus usage priced in successive CCF blocks, with separate non-residential and other service schedules. One CCF equals 100 cubic feet, approximately 748 gallons. Cal Water's current Chico page identifies a Residential Metered Service CH (North Valley Region) schedule effective July 1, 2026, but the live page did not expose the 2026 dollar table during review. The last fully rendered Chico tariff schedule available in the official rate archive used 1-6, 7-18, 19-29, and over-29 CCF blocks.. Bills are generated generally monthly billing, with the bill showing the service period, meter read dates, current charges, due date, and prior balance. the exact read and due-date calendar is premise-specific., and a typical residential cost reference is A dedicated this detail was not publicly posted. For an exact 2026 dollar estimate because Cal Water's current Chico page confirms the July 1, 2026 tariff but its linked rate document did not expose the current dollar values in the live text view. The last fully rendered official schedule, effective May 1, 2024, listed a 5/8 x 3/4-inch service charge of $25.64 and usage blocks of $0.4196 per CCF for 1-6, $2.0062 for 7-18, $2.5351 for 19-29, and $3.8572 over 29; those historical figures should not be treated as the 2026 bill. Sewer, taxes, surcharges, and local adjustments are excluded.. These descriptions are useful planning benchmarks; actual charges can change with meter size, usage, sewer averaging, local taxes, drought stages, or account-specific fees.
Wastewater and sewer calculation
California Water Service bills the Chico potable-water charge. Sewer or wastewater service is generally a separate city or agency charge rather than a Cal Water Chico tariff item. The sewer agency may use actual metered water consumption, a winter average, a residential cap, or a fixed equivalent-unit charge; no single Cal Water formula applies to every Chico and Hamilton City premise. Customers should compare the water meter usage with the separate sewer bill and ask the applicable city or sewer agency for its current base, usage, winter-average, and adjustment rules.
Meter and infrastructure notes
The Chico system uses customer water meters and Cal Water's periodic billing reads. The district page does not publish a fixed local AMI deployment percentage or route day; Cal Water company materials describe AMR/AMI pilots in selected districts but do not establish that every Chico account has an advanced meter. Customers should use the bill's read dates and current/previous reads, review usage history in the portal, and ask Cal Water to confirm the exact meter technology and leak-alert capability for the premise. The Chico supply infrastructure is primarily groundwater: the district reports 68 wells, approximately 27 million gallons per day, 373 miles of pipeline, eight storage tanks, and nine booster pumps.
Emergency water support
Report a leak or water emergency
For water emergencies, main breaks, service-line leaks, flooding, or suspected water-quality problems in Chico or Hamilton City, call the Chico District main and after-hours number, 530-893-6300. Call 911 for an immediate life-safety emergency and avoid contact with contaminated or electrically hazardous water.
Official starting point
Choose the right next step
Reading this profile
A practical reference for Chico and Hamilton City, plus vicinity in Butte and Glenn Counties
California Water Service Company - Chico System is listed here as a private investor-owned utility. The profile separates account actions—such as paying a bill or requesting service—from explanatory material about rates, meters, wastewater, leaks, and delinquency.
Because utility rules can vary by account class, meter size, service address, billing date, and local ordinance, treat the published bill and current provider website as the final authority. Use this profile to locate the correct channel and prepare better questions for customer service.
If your issue is urgent, start with the provider’s emergency number or official payment route rather than waiting for an email response. Keep a written record of calls, confirmation numbers, notice dates, and documents you submit.