How Good is Your Drinking Water

Drinking water can be contaminated, whether it comes from a public or private source. The question arises, at what point does contaminated water become unsafe to drink?

This program is designed to help you assess the water flowing from your own tap or, if you are responsible for a larger system, from the water leaving your pipes. You will learn some of the most common contaminants, how to test your water and how to compare your water test results with federal standards for drinking water. Those standards tell you whether your water is safe to drink. Finally, you can learn what the recommended treatments are if your water is contaminated.

Determining the Type of System You Have

Is your water supply private or public? The standards your water must meet depend on this. Nationally, a public water supply serves at least 15 connections or 25 or more people. These are the water supplies that must meet Environmental Protection Agency (EPA) standards. States may regulate water supplies of fewer connections.

In the state of Washington, 15 connections or 25 or more people signifies a Group A public water system. A Group B public water system is one which provides piped water for more than one single-family residence.

Examples of Group A public water systems include municipal systems (cities, towns, and water districts). Group B public systems include small community systems serving two or more homes, restaurants, motels, campgrounds, churches, and businesses.

For the purposes of this program, if you have your own private well, follow the guidelines for the Group B public water system.

After you have decided which system you have, click on the Group A or Group B/Private button to consider the problems you may encounter with your water supply system.