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Public Water Systems
Any well or water system that provides drinking water for more than a single-family home or two homes on the same parcel is considered a public water system, even if the well is privately owned.
Two-Party Public Water Systems
A Two-Party Public Water System is a shared well that provides drinking water to two connections on two different parcels. A legal agreement should be in place to define each party’s responsibilities to ensure safe drinking water for both parties. After initial water quality testing associated with the building permits, water quality testing is not required, but regular testing is strongly recommended to protect the health of the consumers.
It is recommended that shared well owners test regularly for:
- Coliform bacteria, every year
- Nitrate, every three years
Other recommended testing includes:
- Chloride and conductivity
- Arsenic
In addition to testing, shared well owners must keep the area around the well free from pollutants, such as animal waste, fertilizers, fuels, etc. See Source Protection for more information.
Resources
- Island County Public Health requirements
- Washington State Department of Health requirements
- Guide for Approval of a Public Water Supply for Two-Party Wells
Group B Public Water Systems
Group B Public Water Systems provide drinking water to 3-14 connections and fewer than 25 people a day OR more than 25 people a day for fewer than 60 days a year. Island County Public Health requires regular water quality testing to protect the health of the consumers and current water system information.
It is REQUIRED that all Group B Public Water Systems test for:
- Coliform bacteria from the distribution system every year
- Nitrate from the source every 3 years
It is REQUIRED that all Group B Public Water Systems:
- Update their Water Facilities Inventory report every 3 years and when changes occur
Some systems have additional testing requirements which may include:
- Chloride and conductivity, every April and August
- Arsenic
Group B Public Water Systems with a well located in an area that has seawater intrusion risk rating of medium, high, or very high are also required to test for chloride and conductivity in April and August of each year. Other tests, including arsenic, may be required by the Health Officer. In addition to testing and documentation, Group B Public Water Systems must keep the area around the well free from pollutants. See Source Protection for more information.
Resources
- Island County Public Health requirements
- Seawater Intrusion Monitoring
- Public Water System Seawater Intrusion Risk Rating
- Water Facilities Inventory report (Sentry)
- Water Facilities Inventory report instructions
- Washington State Department of Health requirements
- Washington State Department of Health resources
Group A Public Water Systems
Group A Public Water Systems provide drinking water to 15 or more connections or 25 or more people a day regularly. The Washington State Department of Health (DOH) requires regular water quality testing to protect the health of consumers and current water system information. Island County Public Health may require additional water quality testing.
- For DOH testing requirements, see the Water Quality Monitoring Schedule found on Sentry.
- For DOH water system documentation requirements, contact DOH directly.
- Some systems have additional testing requirements for Island County, such as testing for chloride and conductivity every April and August.
Group A Public Water Systems with a well located in an area that has a seawater intrusion risk rating of medium, high, or very high are required by Island County to test for chloride and conductivity in April and August of each year. In addition to testing and documentation, Group A Public Water Systems must keep the area around the well free from pollutants. See Source Protection for more information.
Resources
- Island County Public Health requirements
- Seawater Intrusion Monitoring
- Public Water System Seawater Intrusion Risk Rating
- Water Quality Monitoring Schedule & Water Facilities Inventory Report (Sentry)
- Washington State Department of Health requirements
- Washington State Department of Health resources
To Find Information About Your Public Water System and Drinking Water:
- Check your water bill, ask your neighbors, look on the county map (ICGeoMap), or email us for your water system name.
- Use your water system name to search and view general information, water quality information (samples and exceedances), and reports on Sentry, the Washington State Department of Health website for public water systems.