Water and chemicals from firefighting foam and other sources

PFAS chemicals can enter drinking water in many different ways. This page has information for water consumers as well as water providers to learn more about these chemicals. More information can be found on our FAQ (en español).

How do these chemicals enter drinking water?

Person filling water glass at kitchen sink.

There are many ways for these chemicals to enter drinking water. In Colorado, we are especially concerned about toxic firefighting foams containing these chemicals. If firefighting foam is left on the ground after putting out a fire, this may allow PFAS chemicals to sink through the soil into groundwater or run off into rivers and streams.

What should I do to make sure my drinking water is safe?

If you receive a water bill, then you are connected to a public drinking water system. If your water bill is included in rent or association dues, contact the manager to determine which system provides your water. If you do not receive a bill, you could be served by a private well.

If you are served by a public water system

We recommend consulting with your water system. Some water systems participated in a sampling project in 2020 to test for these chemicals and you can view the results. We recommend following up with your water system because they may have changed their treatment methods since this project took place.

If PFAS levels are above the EPA health advisory of 70 parts per trillion, you should consider other sources of water such as in-home water treatment or bottled water.


If you have a private well

If you use well water for drinking, cooking food like soup or rice, or gardening, we recommend testing your well water for PFAS chemicals. EPA has a list of labs that can test for these chemicals. We recommend testing for as many PFAS contaminants as the lab offers. Please note the number of labs that can test for these chemicals changes, so this list may not be the most current.

EPA list of certified labs.

Tell the lab you want to test your drinking water for PFAS. A test usually costs between $300 and $500. After receiving results, you should check that PFOA and PFOS combined are below 70 parts per trillion. 

For help interpreting lab results, please contact the department's toxicology hotline:



What if my water has PFAS levels over the health advisory?

Whether you are served by a well or public water system, if you learn that your drinking water has PFAS results above the health advisory of 70 parts per trillion, we recommend you consider other sources of water for drinking, cooking foods like rice and soup, and preparing baby formula. 

Other water sources include bottled water or water treated under the sink by a reverse osmosis system (see in-home treatment information sheet). If you or your family are concerned about your health, contact your health care provider and talk with them about PFAS (see ATSDR guidance document). 

Learn about more actions you can take on our health web page

Additional information for drinking water providers

Water sample collection from test tubes.


To date, there is no national regulatory standard for PFAS chemicals that public water systems need to test for. Under the Unregulated Contaminant Monitoring Rule (UCMR), the EPA periodically requires selected public water systems across the country to gather data on certain contaminants to help determine if they should be regulated in the future. The 2012 list included six PFAS chemical compounds (PFOA, PFOS, PFNA, PFHxS, PFHpA, and PFBS), which water systems monitored from 2013-2015. As a result of this monitoring, some public water systems across the United States, including in Colorado, detected PFAS chemicals.

Guidance document

Drinking water PFAS assessment, prevention, and response toolbox: a guidance document for drinking water providers on how to respond if they find different levels of PFAS in their drinking water.