SEATTLE — Most people don’t think twice about what’s in their drinking water, so KIRO 7 decided to ask the question: How safe is yours?
The answer depends partially on where you get your water.
A majority of Washingtonians get their water from a Group A public water system.
This means the system provides service to 15 or more connections.
“The Group A water systems have a really robust set of regulations and requirements that go along with them,” said Mike Means, the water quality policy and certification manager for Washington’s Office of Drinking Water.
These requirements are overseen by the state’s Department of Health, with some coordination from local governments. There are regular inspections for microorganisms and chemicals.
Then, there are Group B systems. Means estimates that about 150,000 to 200,000 state residents get their water from a Group B water system. These are systems that serve fewer than 15 connections and fewer than 25 people per day.
“There are no ongoing requirements by the state for a Group B water system,” Means said.
Some counties, however, have set their own regulations in place for these systems, including Pierce County. King and Snohomish Counties have not, according to the state’s website.
For Group B systems in counties without local regulations, Means said it’s up to the system owners to regulate their water.
It’s the same, most of the time, for private wells. Around a million people, he said, use individual wells in the state.
Means said private wells are typically only regulated when there’s a building permit or during the sale of a house.
“The greatest risk, really, we have for that microbiological is the condition of the systems,” he said. “A lot of our systems are getting old, and the infrastructure is getting old, and so how do we make sure that’s maintained and replaced? Especially for the smallest systems, it’s a challenge. If you have a 15-connection system, has that homeowners association saved enough money to replace all those pipes?”
Means recommends that residents in a Group B system or using a private well conduct their own regular testing.
“You can go to a drinking water certified lab and run the test,” Means said. “They cost something in the range of $30 to $50, depending upon where you’re at.”
Means recommends regular microbiological testing. Group A systems undergo this testing monthly.
He also recommends testing your system for nitrate at least once a year. Means said that nitrate is a good chemical to sample because it can show an impact on groundwater. If you start seeing nitrate levels go up, you might consider sampling for other chemicals, too.
When it comes to regulated water, some environmental groups say current federal regulations don’t go far enough.
“For a lot of contaminants, they are regulated, but maybe not at levels that are keeping up with the latest health science,” said Sydney Evans, Senior Science Analyst on the Science Team at the Environmental Working Group. “Then there are quite a number of contaminants that aren’t regulated at all.”
The Environmental Working Group (EWG) has published its own safety standards for water, that go beyond that of current federal regulations.
EWG analyzes utilities based on their public data and tracks levels of contaminants within its water. You can look up your public utility here and see how EWG ranks it.
EWG’s analysis of Seattle Public Utilities (SPU), for example, found 11 contaminants exceeding its health guidelines.
In a response to EWG’s data, a spokesperson for SPU said the utility’s “water quality test results for Seattle Water are better than state and federal regulated levels designed to protect public health.”
The spokesperson added that the utility’s water comes from two protected watersheds in the Cascade Mountains.
These watersheds are closed to public access and free of agricultural, industrial, and recreational activities, allowing SPU to greatly reduce the risk of contamination.
“Although we don’t know the science behind how the Environmental Working Group arrived at its health guidelines, SPU is always supportive of measures to make tap water as safe as possible for the public,” the spokesperson wrote. “More information about Seattle Water can be found in our latest Drinking Water Quality Report."
“On a day-to-day basis, most people’s tap water is not going to make them sick,” Evans said. “There are contaminants present that over long periods of time are going to raise the risk for certain health harms.”
Changing regulatory systems can be difficult and take time, Evans said.
The state does have the authority to establish regulations, too. Means points to PFAS or “forever chemicals” as an example. He says the state passed rules governing these chemicals before the federal government did.
So what can you do as an individual to improve your water quality?
“We don’t think it should be on the burden of any individual to worry about their water safety,” Evans said. “That being said, (improving water standards) can be a very slow process, and for those people who are in a position where they want to take action, there are steps that you can take.”
Evans said the “single most effective thing you can do as an individual” is to filter your water.
There are many kinds of home filters and many are very effective, she said. Choosing one can depend on which type of contaminant you’re trying to remove.
“It’s important to do your research, especially about the claims of any individual filter,” she said. “But they are very effective on a wide range of contaminants.”
EWG has posted its own guide here.
Evans said that bottled water is not typically the answer, except in extreme situations like natural disasters and acute pollution due to spills.
It’s more expensive and can have environmental impacts. There’s also the concern of microplastics, Evans said.
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