Group A Community Water Systems

Information on this page is geared to the specific needs of Community water system owners and operators to make their jobs easier and help them comply with federal and state requirements.

Community water system means any Group A water system providing service to 15 or more service connections used by year-round residents for 180 or more days within a calendar year, regardless of the number of people, or regularly serving at least 25 year-round (i.e., more than 180 days per year) residents.

Examples of a Community water system might include a municipality, subdivision, mobile home park, apartment complex, college with dormitories, nursing home, or prison.
Community water systems are regulated under Chapter 246-290 of the Washington Administrative Code. The following is a summary of your requirements in each of our specialty programs. 

Program Requirements

Coliform Bacteria. Start sampling for coliform bacteria according to the schedule on the second page of your Water Facilities Inventory (WFI) form in Section 33 or on your Water Quality Monitoring Schedule (WQMS). The coliform schedule specifies the minimum number of coliform samples required from your water system each month per WAC 246-290-300. For questions, contact the regional office. 

Nitrate Monitoring. Check out the nitrate monitoring schedule on the second page of your WFI form, which is in Section 34. You may also find it on your Water Quality Monitoring Schedule (WQMS). For questions, contact the regional office.

Certified Operator. A certified operator(s) is required to oversee the daily operational activities of the public water system, water treatment facility, and/or distribution system per WAC 246-292-020. For questions, contact Headquarters staff.

Water Quality Monitoring Schedule. To better understand your source monitoring requirements, we developed an online Water Quality Monitoring Schedule (WQMS) for your use. The WQMS provides the schedule of your source and distribution monitoring requirements, the overall monitoring frequency, and lists any monitoring waivers previously granted. You can find your WQMS online at the Sentry Internet database and by following our Quick Start Instructions. Please note it may take up to one week for your WQMS to display in Sentry. For more information, contact the regional office.

Planning. Planning is the foundation of a safe, successful, and sustainable public water system. You are required to maintain one of the two types of planning documents for water systems: a Water System Plan or a Small Water System Management Program. For questions, contact the regional office. 

Engineering. Engineering requirements are applicable for new projects, construction, treatment changes, source changes, or other engineering concerns. Each regional office has engineering staff that are assigned to specific counties to provide technical assistance and review of water system design. For questions, contact the regional office. 

Sanitary Surveys. All Group A water systems are required to have a sanitary survey once every three or five years per WAC 246-290-416. A sanitary survey is a periodic inspection of water system facilities, operations and records used to identify conditions that may present a sanitary or public health risk. The Office of Drinking Water (ODW) conducts sanitary surveys. However, in some counties, ODW contracts with local health jurisdiction staff or an independent consultant to conduct the surveys. A fee will be charged for the sanitary survey per WAC 264-290- 990(3)(c). For questions, contact the regional office.

Operating Permit and Operating Permit Fees. All Group A water system owners are required to obtain an annual operating permit and pay the appropriate fees per WAC 246-294. Operating permit fees are calculated based on information you report on your WFI form. Fees vary based on system type and size and are explained on the back of the annual fee statement/application form that is sent out each year. For questions, contact regional office or Headquarters. 

Accredited Drinking Water Laboratory. All water quality samples must be analyzed at an accredited drinking water laboratory. To ensure your system receives proper credit for samples, remember to include your public water system identification number, which is a combination of the first five-digits and letters on all submitted samples. Fully complete each section of the chain of custody lab analysis form. Incomplete or unreadable lab analysis forms may result in the need to re-sample. Lab personnel can provide you with instructions on how to collect samples for various tests. To find a list of accredited labs in your area visit the Department of Ecology lab search website. For questions, contact Headquarters. 

Water Facilities Inventory (WFI) Form. All owners of Group A water systems are responsible for keeping their WFI information current and accurate within 30 days of any change to WFI information WAC 246-290-480(2). Even if no changes to your WFI information have occurred, owners are still required to submit a signed and dated WFI form to this Department each year. You can download a copy of your current WFI through Sentry Internet. All you need is your Public Water System (PWS) ID number. For questions, contact the regional office or Headquarters. 

Recommended Reading and Publications 331-717. A list of key guidance documents covering a wide variety of topics and drinking water regulations that you should become very familiar with. Each document title is hyperlinked to that specific document.

Additional Requirements

Seasonal Water SystemIf your water system is occupied only part of the year, start-up and shut-down procedures are important to follow to ensure your water is safe to drink. Collect several coliform samples at different locations in your distribution lines two weeks prior to opening the water system to the public. These coliform samples are additional to the required coliform samples and are for water system’s information only. Please follow the procedures provided in Start-Up Procedures for Non-Community Water Systems 331-310 (PDF) and Shutdown Procedures for Non-Community Water Systems 331-311 (PDF). For questions, contact the regional office. 

Surface Water SystemsIf your water system has surface water sources, they are subject to extensive federal and state requirements to protect public health. Group A surface water sources are subject to requirements identified in Part 6 of Chapter 246-290 WAC. This regulation complies with the federal Surface Water Treatment Rule and includes filtration, disinfection, operating, monitoring, and reporting requirements. For questions, contact your regional office. 

For Assistance

If you have any questions, please reach out, we’re here to help! Most programs have a regional contact who is an expert in your area.

If you need more information, contact your Regional Office. The Regional Office Map (PDF) outlines counties in each region.

Eastern Regional Office Staff

Northwest Regional Office Staff

Southwest Regional Office Staff

Headquarters Drinking Water Staff