In-person service is not available at this location; however, our customer service representatives are happy to serve you by phone or email. In-person and other payment options are detailed on the Payment Options page.
Serving Atherton, Bear Gulch, Kings Mountain, Los Trancos, Portola Valley, Skyline, and Woodside, and portions of Menlo Park and Redwood City
Cal Water has provided high-quality water utility services in the communities of Portola Valley, Woodside, Atherton, and portions of Menlo Park, Redwood City, and San Mateo County since 1936. Skyline County’s water system became part of the Bear Gulch district in 2009, Skylonda Mutual became part of our system in 2023, and Kings Mountain was added in 2024. To meet our customers’ needs, we use a combination of local surface water and surface water purchased from the City and County of San Francisco (SFPUC). The local surface water, about 11% of our total supply, comes from our 1,200-acre watershed in the Woodside hills; it is collected and treated at our reservoir and treatment plant in Atherton. The remaining 89% of our supply is purchased from the SFPUC.
Frequently Asked Questions
How do I read my bill?
Cal Water’s bills feature an easy-to-read account summary, usage history graph to help customers keep track of consumption, detailed description of charges, a place for important messages, and meter information.
A sample bill is below.
1
Account number: Your 10-digit account number, which you will keep even if you move to another location within our service areas (if you receive more than one bill from Cal Water, you will have more than one account number—contact our Customer Center at the phone number on your bill if you would like your bills combined)
2
Billing date: Date your bill was printed
3
Contact information: Your local Cal Water Customer Center
4
Customer messages: Where important messages will appear
5
Summary of your account information
6
Prior balance: Previous balance; includes any unpaid balance; due upon receipt
7
Payment received: Payments applied to your account since your last bill
8
Current charges: Amount due from current billing period (flat or metered as applicable)
9
Total amount due: Amount that you owe, including any unpaid previous balance (all bills due upon receipt and past due after 19 days)
10
Additional customer messages
11
Summary: Overview of your current bill, including the amount due
12
Automatic Payment Service: Instructions for signing up to have your bill automatically paid each month from your checking account
13
Portion of bill to return your payment (unless enrolled in automatic payment)
14
Billing address: Address to which your bill is sent (this may be different than the service address)
How to read your water bill
Customer messages: Where additional important messages will appear
16
Service address: Address of service location
17
Service dates: Beginning and end of the billing period for water service
18
Service charge: Monthly charge based upon the size of your water meter (if applicable)
19
Quantity charges: Measured in Ccf (hundred cubic feet) and separated by tier (if applicable)
20
WRAM charges or credits: The Water Revenue Adjustment Mechanism (WRAM) is used so that Cal Water does not over- or under-collect fixed costs needed to operate the water system
21
CPUC Fee: The California Public Utilities Commission’s fee to cover its oversight.
22
Other charges and credits
23
Public Purpose Program fees
24
Subtotal for this service
25
Drought water budget: Summary of your current usage as it compares to your water budget
26
Water services detail: Graph of your consumption history for the past 13 months
27
Meter and reading information: Details of when your meter was read and what the reading was
28
Additional services detail: Insurance and other optional services, or city services
How to read your water bill continued
What forms of payment does Cal Water accept?
You can pay your Cal Water bill with cash, a check, a money order, a credit card, a debit card, or bank account. However, available payment options vary depending on the payment location or method. For more detail, see the Payment Options page.
What is the Customer Assistance Program (CAP)?
Cal Water offers a Customer Assistance Program (CAP — formerly LIRA) to customers who meet income guidelines. Qualifying customers receive a discount on their monthly service charge. You can visit the CAP page to see if you qualify and download an application form. If you live in a single-family residence, you can also apply online.
What should I do if my bill seems higher than usual?
See the High Bills page for more information and suggestions.
How do I turn off the water supply to my house in the event of a break in my plumbing or a repair?
You can interrupt the flow of water to your home by turning off your house valve. House valves are usually located beneath a faucet outside the home, most typically near the faucet for the garden hose. If you cannot find your house valve, please contact your local Customer Center for assistance.
Payment Mailing Address
California Water Service P.O. Box 7229 San Francisco, CA 94120-7229
Automated Payment Number
(888) 598-9824
Rebates
Rates
Customer Assistance: We’re Here to Help
Cal Water has services and programs to assist you in a variety of circumstances.
