State Regulated Public Water Systems
Definition of a Public Water System (PWS)
“Public Water System” means a system for the provision of water for human consumption through pipes or other constructed conveyances that has 15 or more service connections or regularly serves at least 25 individuals daily at least 60 days out of the year.
If you receive water from a State of California regulated public water system, information on this page can help you figure out who your water provider is, what your water quality is, and who to contact if you have concerns.
In California, some county environmental health departments, also known as Local Primacy Agencies (LPAs), have been delegated the authority to regulate PWSs with less than 200 service connections. The State of California oversees the LPAs. Click here for: Map of the LPA counties or LPA contact information. Whether the State or an LPA regulates a PWS, you can find information about a PWS’s water quality by following the instructions below.
In order to find water quality information about a specific public water system, you must know the name of the water system or the public water system ID number.
Determine the name and/or ID number of the water system. Click below for instructions.
If you already know the water system name or ID number and want to find water quality information, click below.
Still Need Help?
Call your local State Division of Drinking Water office.
Click below to access a map with contact information.
General PWS Information
For general information about public water systems in California click below.
Option 1 - Look at Your Water Bill
If you receive a water bill you can find the name of your water supplier on the bill. Use this name when using the websites under Step 2 to find information about your water quality. If you do not receive a water bill (for example, you are a renter and your landlord pays for your water bill), Click here to find out where your drinking water comes from.
Definition of Community Water System
"Community water system" means a public water system that serves at least 15 service connections used by yearlong residents or regularly serves at least 25 yearlong residents of the area served by the system.
Option 2 – Use the interactive Human Right to Water (HR2W) Portal Map
The HR2W Portal map allows you to determine a public water system name and ID number, by either using a known address or by clicking on an area of the map you’re interested in. Please note this mapping tool does not include all public water systems. It only includes community water systems, schools, and daycares. Once on the HR2W webpage, scroll through and read all the instructions on the left to familiarize yourself with use of the map until you get to Item 2, “How to Find a Public Water System”, and follow the instructions.
Option 1 - Call the Office of the Water System that Provides Your Water
Check your water bill to find the contact information for the public water system that provides your water. If you are a renter, ask your landlord for the water system contact information; or if you know the name of the water system that provided your water, you can find their contact information on the internet. Contact them and ask them any questions you may have about the quality of the water they provide; and if you have not received an annual Consumer Confidence Report (CCR) from the water system, you can ask them for a copy of the most recent version, see below for information on CCRs.
Option 2 - Consumer Confidence Report (CCR)
Regulated public water systems are required by law to provide an annual Consumer Confidence Report to their customers that provides information about the quality of the water. If you have not received a CCR directly and you would like to see one for a particular water system, contact the water provider to obtain a copy. Some water providers post their CCRs on their websites. Some CCRs can also be found in Drinking Water Watch (DWW). You can search for your public water system by name or public water system number (see Step 1 above). Once in Drinking Water Watch, if there are any CCRs, links to them can be found in the blue bar on the left-hand side of the page under “Consumer Confidence Reports”.
Option 3 - Drinking Water Watch
The Safe Drinking Water Information System (SDWIS), accessible through DDW’s Drinking Water Watch (DWW) website, provides specific information about California’s public water systems. You can search for your public water system by name or public water system number (see Step 1 above). Once you have located your water system in Drinking Water Watch click on the tab at the top of the page that says “Water Quality”.
Option 4 – Check the Interactive Human Right to Water (HR2W) Portal Map
Please note this mapping tool does not include all public water systems. It only includes community water systems, schools, and daycares. Once on the HR2W webpage, scroll through and read all the instructions on the left to familiarize yourself with use of the map until you get to Item 4, “How to View Details for ‘Out of Compliance’ and “Returned to Compliance’ Systems”, and follow the instructions.
Option 5 - Call the State Division of Drinking Water District Office Nearest You
If you have a concern or question that you have not found answers for, contact the Division of Drinking Water District office nearest you.
Option 6 – Do your own water quality testing