Thurston County, Washington

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Thurston County Washington

Public Health and Social Services

Drinking Water & Wells

Click Here To Visit Our Water Lab

The goal of the Drinking Water Program is to ensure that Thurston County residents have a safe supply of drinking water, this is done by:

• Reviewing water system plans for small water systems (WA Dept of Health reviews large systems).
• Inspecting sites for proposed drinking water wells to ensure that they are located away from sources of potential contamination.
• Ensuring that building sites have an approved source of drinking water available before issuing building site approvals.
• Reviewing water quality monitoring data from small water systems (WA Dept of Health monitors large systems).

• ​​​​​Group A Public Water Systems are classified as a community system with 15 or more connections or serves greater than 25 or more people per day for 60 days or more per year.
• Group B Public Water Systems are classified as a community system with 3 to 14 connections and less than 25 people per day or serves 25 or more people per day during fewer than 60 days per year.
• Two Single-Family Residential Water Supply is one well serving two residences. Three or more connections are regulated by Article III of the Thurston County Sanitary Code as a Group B public water system.
• Non-Public Well is classified as a single-family well with 1 single family residential connection or irrigation well.

Group A water systems are regulated by the Washington State Department of Health, Southwest Regional Office (360-236-3030). In cooperation with DOH, Thurston County performs well siting inspections for new wells and sanitary surveys for small Group A systems. For more information about your water system search the DOH public water system database.

Applications and Forms

Well Site Inspection (both Supplemental and Master Applications required)

• Supplemental Application
• Master Application

Covenants

• Declaration of Covenant
• Public Water Source (Note: follow link to Auditor's Formatting Requirements)
• Covenant Fact Sheet
• Restrictive Covenant
• Public Water Source (Note: follow link to Auditor's Formatting Requirements)
• Covenant Fact Sheet
• Well Construction or Decommissioning Inspection

Group B water systems have 3 to 14 service connections and less than 25 people per day or serves 25 or more people per day during fewer than 60 days per year. The WA State Department of Health (DOH) and local health jurisdictions share administrative responsibilities for these systems. All Group B systems in Thurston County are regulated by the Environmental Health Division.

Water System Approval Process

All Group B systems are regulated by the Thurston County Environmental Health Division (Environmental Health Division). These systems must comply with Article III of the Thurston County Sanitary Code, WA State DOH requirements of Chapter 246-291 WAC Group B Public Water Systems, and associated Design Workbook and Design Guidelines (help you complete the workbook) for Group B Public Water System Approval.

For projects located within a city jurisdiction or Thurston County Coordinated Water System Plan Urban Service Area, additional standards may apply.

One well serving two residences is a separate classification than those with 3 or more connections. These water systems are classified as 2 Single-Family Residential water supply and are regulated by the Environmental Health Division. For more information regarding these water systems see the section titled 2 Single-Family Residential Water Supply below.

NOTE: Expansion of a 2 Single-Family Residential water supply to provide additional connections will require the supply to meet all the requirements of Article III that apply to public water systems. This includes a design of the proposed system expansion by a qualified professional engineer and subsequent approval by the Health Department.

Review Process / Final Approval

Submit copy of an approved Well Site Supplemental Application. See Well Site Application/Inspection for requirements described below.

NOTE: An approved Well Site Application is required prior to drilling and before the Water System Design Application can be submitted.

Submit the following completed records:

• Group B Public Water System Design Application
• Preliminary Engineering Report (see below) prepared by a Washington State licensed professional engineer.
• Associated documents: Satellite Management Agency information (see below), draft Well Isolation Covenants (see below), easements, operations and maintenance agreements, well driller's report, and water quantity and quality reports.

Staff will review the water system design and Preliminary Engineering Report and send a letter granting preliminary water system approval, if all the requirements are met.

After the water system design has received preliminary approval and construction is completed, the engineer shall inspect the water system to assure compliance with the approved construction documents.

Within sixty (60) days of the inspection, the professional engineer shall submit a completed Certificate of Inspection and Installation of Public Water System Projects form along with the Final Engineering Report (see below).

Staff will review the documents and grant final water system approval and the required sampling frequency, if the requirements are satisfied.

Staff will recommend approval of the Certificate of Water Availability (COWA) after the water system has been granted final approval.

NOTE: If the water system is within a city jurisdiction or Thurston County Coordinated Water System Plan Urban Service Area, the Environmental Health Division will mail the application to the applicable jurisdictional authority and will hold permit issuance until their review and comment is completed.

Well Site Application/Inspection

Prior to drilling a new well or obtaining approval for an existing well, the location of the well must first be approved by the Health Dept. Submit a completed Master Application and Well Site Supplemental Application package to the Permit Assistance Center with the applicable fee (see Fee Schedule) Also submit with the application:

• Project site plan — include the proposed well site, 100-foot sanitary control area around the well, any structures, all septic system components, drainage ditches, stormwater infiltration ponds, and public roads within 200 feet.
• Proposed well site — location flagged on the property

NOTE: Complete application package requirements are outlined on the Well Site Supplemental Application and Well Site Application Guidelines.

Health Dept staff will review the well site application and issue approval if all requirements are met. (This includes an on-site evaluation of topography, potential contaminant sources, and hydrologic suitability of the well location.) Once the well site has received approval, contact a licensed well driller to have the well drilled and tested for capacity and water quality.

NOTE: Prior to drilling, a Start Notification should be sent to both the Washington State Department of Ecology and Thurston County Environmental Health Division, by the well driller. For additional information and application form, see For Well Drillers Only.

Preliminary Engineering Report (Design Report)

A Preliminary Engineering Report, including detailed plans and specifications for the proposed water system, shall be prepared and submitted by a Washington State licensed professional engineer for review and approval.

The preliminary report shall follow the guidelines in the Group B Workbook, including Satellite Management Agency (SMA) information (see below), draft documents (covenants, easements, operations and management agreements), well driller's report, water quantity and quality reports, and construction documents.

Final Engineering Report

Upon completion of the water system construction, the professional engineer shall inspect the system to assure compliance with the approved construction documents. Within sixty (60) days, the professional engineer shall submit a completed Certification of Construction and Inspection form, along with the Final Engineering Report, to the Environmental Health Division.

It is important that all items listed in the plan approval letter are submitted in the report in order to avoid delaying the final review and approval of the project.

The final engineering report will be reviewed by Environmental Health Division staff and a letter will be sent to the system owner (and a copy to the professional engineer) upon approval. The letter will indicate the required sampling frequency. The system is now ready for use.

NOTE: Projects having staged construction shall submit certification document for each separate stage prior to approval and use of any segment.

Satellite Management Agencies

All new water systems shall be owned or professionally managed by an approved Satellite Management Agency (SMA). For the names of SMAs serving Thurston County, see List of Approved Satellite Management Agencies [DOH].

It is important to contact the SMA prior to system design so that the agency's design and operating requirements are incorporated into the design. A draft contract with the proposed SMA should be submitted with the Preliminary Engineering Report. If an SMA is unavailable, contact Thurston County Environmental Health.

Well Isolation Covenants

The owner of a public water supply is required to have physical control over the well isolation area (normally a 100-foot radius). Generally, this is accomplished through the filing of protective covenants (either a Declaration of Covenant or Restrictive Covenant, or both) for the well isolation area.

• Declaration of Covenant — filed when the water supplier owns all or part of the area in the sanitary control area
• Restrictive Covenant — filed when someone other than the water supplier owns portions of the sanitary control area

It is important that the covenants are obtained prior to drilling a well or completing the water system design (see Covenant Fact Sheet for instructions and examples).

Group B systems have many requirements, from both the state and local jurisdictions. Systems failing to meet these requirements are subject to enforcement action. This may include notifying customers, lending institutions, or local building authorities about system inadequacies, which could affect loan approvals and building permits. Key operating requirements are listed below. To read the complete requirements, go to the Washington Administrative Code (WAC 246-291). For questions about other sources of drinking water, contact the DOH at 800-521-0323.

Sampling Requirements

• Bacteria — Collect a water sample and have it analyzed for coliform bacteria at least once every 12 months. The sample should be taken at the farthest end of the distribution system, or as directed by the Environmental Health Department.
• Nitrate — Collect a water sample and have it analyzed for nitrate every 36 months. NOTE: For new systems, this requirement begins 36 months after an initial inorganic and physical analysis.
• Other Contaminants — Additional samples are required in areas of known contamination, or if treatment is provided for any inorganic chemical or physical contaminant. Systems providing treatment must collect samples before and after treatment. The Health Dept will determine how often samples must be taken.
• State-certified lab analyzes all samples — All samples should be tested by a state-certified lab. For a list of certified laboratories, visit the WA State Dept of Ecology Certified Water Laboratories Database.
  NOTE: In order to receive monitoring credit, the water system name, identification number, and system type (Group B) must be included on the lab form submitted with the water sample.

For instructions on collecting a water sample for the County water lab, see Water Testing Instructions and Pick-up Locations

System Maintenance and Operation

• Sanitary control area — Protecting a water source from potential sources of contamination is one of the most important aspects of owning and operating a public water system. The system owner must maintain and enforce covenants to protect source water. Covenants generally cover a 100-foot radius around the well, but the size of the protected area may vary.
• System operation and reliability — You must guard against contamination from unprotected cross connections, and conduct operations and maintenance in a way to minimize failures and provide safe, reliable water to customers. If power outages, pump failures, or other problems occur, you must notify your system customers.
• Conserve water — All water systems should conserve water. The Health Department may require newer systems to incorporate specific conservation measures. For tips on conserving water, see Water Conservation Tips (WA Dept of Ecology). NOTE: If your system-wide water use exceeds 5,000 gallons a day, or the total property being irrigated by the system exceeds one-half acre, you must get a water right permit from the Department of Ecology.
• Budgeting — All water systems should budget and establish rates to meet expenses. Contact the Health Department for information on water system budgeting.

Public Notification

• A purveyor of a Group B system shall notify department, health officer, and all system consumers within twenty-four hours when the purveyor:
  • obtains a water quality sample analysis from a certified lab indicating the presence of E. coli;
  • Obtains a water quality sample analysis from a certified lab indicating the presence of nitrate at a concentration at or above 10.0mg/L;or
  • Is aware of circumstances that pose a threat of acute contamination, such as a flood event.

  Additional Resources

  • Expansion — Before a system expands beyond the existing number of approved connections, plans should be submitted to the Health Department for approval. If more than 14 residences eventually will be served, proceed as if you have a Group A public water system. See WAC 246-290 for requirements.
  • Additional Resources for Group B Public Water Systems
    • General Information (WA DOH)
    • Group B Management Guide
    Two Single Family Water Supply

    One well serving two residences is considered a 2 Single-Family Residential water supply. Three or more connections are regulated by Article III of the Thurston County Sanitary Code as a Group B public water system.

    Rules and Regulations

    • Article III — Thurston County Sanitary Code
    • WAC 246-291 — Washington Administrative Code

    Recommendations

    1. The pump should be capable of producing a minimum of 800 gallons per day. A minimum 20 psi at maximum demand should be supplied to each property line or residence.
    2. The pressure tank(s) should be sized so that the drawdown provides adequate pump protection and/or storage.
       Pump protection: 2.5 x pump rate = gallons. (This is the minimum drawdown capacity of the tank.)
    3. Prior to use, the newly constructed supply should be disinfected with a chlorine dosage of no less than 10 parts per million (ppm) as measured after a contact time of 24 hours (10 ppm is equivalent to approximately 1 quart chlorine bleach per 1,000 gallons water).
    4. Develop a Shared Well Agreement between the two parties.
    5. Evidence of well and waterline access agreement filed with the Thurston County Auditors' office if the two respective parcels sharing the well are separate legal lots of record.
    6. Test for coliform bacteria every year and nitrates every 3 years.

    NOTE: Expansion of a 2 Single-Family Residential water supply to provide additional connections will require the supply to meet all the requirements of Article III that apply to public water systems. This includes a design of the proposed system expansion by a qualified professional engineer and subsequent approval by the Health Department. For additional information, see Group B Public Water System Design Supplemental Application.