Back to top

PFAS

PFAS, short for perfluoroalkyl and polyfluoroalkyl substances, are chemical compounds manufactured and used for decades to repel water, grease and oil. They can be found in many common products, including fire-fighting foam, carpets, clothing, nonstick cookware, food packaging, plastic, coasting, dental floss and some high-end ski waxes. 

The chemicals don’t easily break down, earning themselves the nickname the “forever chemicals.” Research by the Centers for Disease Control and Prevention show most people in the United States have been exposed to some PFAS. Research suggests exposure to high levels of certain PFAS may lead to health impacts.

Denver Water is committed to ensuring a clean, safe water supply for our customers. Our water quality experts have been studying the evolving information about the chemicals and involved in discussions with legislators, state and local regulators and other utilities on how to best find, control, remove and prevent PFAS contamination in water. 

We also have tested for PFAS-related compounds in source water and drinking water as the water comes into and goes out of the treatment plants since 2017 and have not detected anything above the reportable limit .

FAQs

How can PFAS get into the water supply?

Because PFAS is so widely used, the chemicals can get into the water cycle in a number of ways. 

Firefighting foam can seep into groundwater supplies. PFAS-containing products in landfills can break down and the chemicals can leach out of the landfill. When PFAS-containing products — such as cookware, cosmetics or water-resistant clothing — are washed with water, trace amounts of the chemicals can be carried down the drain and into the community’s wastewater system.
 

How is PFAS in drinking water regulated?

Because the chemicals are in so many products used every day and don’t break down on their own, surveys by the Centers for Disease Control and Prevention show that most people in the United States have been exposed to some PFAS. Current scientific research suggests exposure to high levels of certain PFAS may lead to adverse health outcomes; more research is underway.

At the same time, a spotlight has been put on the water and wastewater industries to remove these widely used chemicals from our environment, even the trace amounts that may appear in the water system. 

The Environmental Protection Agency in 2016 issued a health advisory asking drinking water providers to test for two specific kinds of PFAS (called PFOA and PFOS) and look for anything over 70 parts per trillion (a tiny, tiny amount). In June 2022, EPA issued a new, interim health advisory on those two kinds of PFAS in drinking water with significantly lower limits (far lower than that 70 parts per trillion in the 2016 advisory). Learn more about EPA health advisories.

On March 14, 2023, the Environmental Protection Agency proposed the first-ever national standard to limit PFAS in drinking water. Learn more here.

At the state level, in 2022 Colorado’s Gov. Jared Polis signed a new law (House Bill 1345) that will gradually restrict the sale of PFAS in consumer products, as well as fluids used in the extraction of oil and gas products, starting as early as 2024.

The new state law will prohibit the sale or distribution in Colorado of products that contain PFAS, such as cosmetics, carpets or rugs, fabric treatments, food packaging and juvenile products. Cookware that contains PFAS will have to carry a label.
 

What is Denver Water doing about PFAS?

Denver Water is committed to ensuring a clean, safe water supply for our customers. Our water quality experts have tested for PFAS-related compounds in the source water that comes into our treatment plants and the drinking water that leaves our treatment plants since 2017 and have not detected anything above the reportable limit. 

Also, our water quality experts and scientists have been closely studying the evolving information about these chemicals and preparing for solutions in case future test results are above EPA-recommended levels. 

We also have been involved in discussions with legislators, state and local regulators and our sister utilities on how to best find, control, remove and prevent PFAS contamination in water.
 

Denver Water PFAS testing

Our water quality experts have tested for PFAS-related compounds in the source water that comes into our treatment plants and the drinking water that leaves our treatment plants since 2017 and have not detected anything above the reportable limit. The results below are the latest sampling results from 2022.

Current laboratory equipment can reliably detect and quantify compounds down to slightly less than 2 parts per trillion in a sample. Below that level, the tiny trace amounts are so small that test results at these extreme detection limits are only estimations.

Prior to June 15, 2022, the EPA set PFOA and PFOS health advisory limits at 70 parts per trillion (ppt). On June 15, 2022, the Environmental Protection Agency released much lower lifetime health advisories for the two PFAS compounds, PFOA and PFOS, and also issued interim health advisories for two additional compounds — GenX and PFBS. Learn more about EPA health advisories.

On March 14, 2023, the EPA proposed the first-ever national standard to limit PFAS in drinking water. Learn more about the draft rule here. An initial review of the EPA’s proposal indicated the water coming into Denver Water treatment plants and the drinking water provided to customers tests well below the proposed limits the EPA suggested for various PFAS compounds in its draft rule.

Denver Water will continue testing for PFAS as part of our monitoring protocols. We regularly review our treatment processes and adjust these processes as part of our mission to provide clean, safe, reliable water to our customers.

Note: The symbol “<” means “less than” and “ppt” means “parts per trillion.”
PFAS EPA Drinking Water Lifetime Health Advisory (ppt) Source Water 2022 Treated Water Results 2022
    Marston Treatment Plant Foothills Treatment Plant Moffat Treatment Plant Marston Treatment Plant Foothills Treatment Plant Moffat Treatment Plant
GenX 10 (Final) <4.0 ppt <3.7 ppt <3.7 ppt <1.9 ppt <1.9 ppt <1.9 ppt
PFBS 2000 (Final) <2.0 ppt <1.9 ppt <1.8 ppt <1.9 ppt <1.9 ppt <1.9 ppt
PFOA 0.004 (Interim) <2.0 ppt <1.9 ppt <1.8 ppt <1.9 ppt <1.9 ppt <1.9 ppt
PFOS 0.02 (Interim) <2.0 ppt <1.9 ppt <1.8 ppt <1.9 ppt <1.9 ppt <1.9 ppt

Footnote: These December 2022 test results reflect the detection limits of laboratory analysis, with results for different compounds ranging from less than 1.8 parts per trillion to less than 4.0 parts per trillion, due to the process individual water samples underwent for preparation and analysis at the laboratory.

What can you do about PFAS?

You can help! Learn more about where PFAS is used in our society and about alternative, PFAS-free products that you could use instead. This will not only protect your health, but also reduce the amount of PFAS in circulation. 

Several groups are working on lists of PFAS-free consumer goods, including PFAS Central.org.