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Per- and Polyfluoroalkyl Substances (PFAS)#

Para obtener más información sobre las sustancias perfluoroalquiladas y polifluoroalquiladas (PFAS), también conocidas como productos químicos eternos, ingrese en

Poudre River

Per- and polyfluoroalkyl substances (PFAS) are a group of 1,000+ man-made chemicals that include PFOA, PFOS and GenX. There is evidence that exposure to PFAS can lead to adverse human health effects. These chemicals are widespread and very persistent in the environment and the human body. They don’t break down and can build up over time. 

PFAS are used to make carpets, clothing, furniture and cookware resistant to water, grease and stains. These substances are also used to fight fires at airfields and are included in some industrial processes. Wildfire fighting retardants are a mix of water, colorants and fertilizer and do not contain PFAS.

PFAS enter the water system when people wash, rinse or clean products containing the chemicals. That water then drains into water bodies or the sewer system, which leads to water reclamation facilities where the water is treated and released back into the water system. 

Current water and wastewater treatment processes are not effective at removing these compounds from water supplies.

What are common sources of PFAS?

  • Shampoo
  • Non-stick cookware
  • Stain-resistance product
  • Paints
  • Pesticides
  • Fast food packaging
  • Firefighting foams
  • Commercial household products
  • Certain textiles
  • Manufacturing facilities
  • Industrial processes

Where have PFAS been Found?

  • Rainwater
  • Wastewater
  • Drinking water
  • Soil
  • Air
  • Food
  • Firefighting foam
  • Food packaging
  • Dust
  • Personal care products
  • In our bodies
rain water, drinking water, soil, air, firefighting foam, food, food packaging, dust, personal care products and your body icons

Health Advisory#

The Environmental Protection Agency (EPA) is responsible for overseeing the National Primary Drinking Water Regulations. These regulations establish what are called “maximum contaminant levels" (MCLs) for specific substances. Public water utilities are required to monitor for these regulated substances. MCLs are in development but have not yet been established for PFAS.

The EPA can also issue Health Advisories for substances that don’t have MCLs. In these cases, these substances have the potential to negatively impact human health and are known or anticipated to occur in drinking water. Adverse health impacts are not expected with lifetime exposure levels below the health advisory.

In 2021, new data on health impacts and widespread exposure to PFAS over a lifetime became available. On June 15, 2022, the EPA released four revised drinking water health advisories for PFAS. 

The new advisory levels of are much lower than previous levels (0.004 and 0.02 parts per trillion (ppt)) and are below any lab's ability to measure at this point in time. 

Health advisories are:

  • Non-enforceable 
  • Established to protect all people, including sensitive populations, from exposure throughout their lives.
  • Calculated to offer a margin of protection 
  • Taking into account other potential sources of exposure beyond drinking water 
  • Based on human and animal studies 

What Utilities is Doing

  • Monitoring for PFAS.
  • Providing the latest data and other pertinent information online.
  • Keeping up with activities in the Cache la Poudre and Horsetooth watersheds.
  • Staying updated on EPA and CDPHE PFAS general direction and activity.

What You Can Do

Avoid or minimize the use of products that contain PFAS (products that are non-stick or stain resistant).

Find products that are free of PFAS »

Frequently Asked Questions (FAQs)#


*PFAS Chemical 

2022 Health Advisory level (PPT*) 

2016 Health Advisory level (PPT*) 

2009 Health Advisory level (PPT*) 












Combined PFOA & PFOS 

No Advisory 


No Advisory 




No Advisory 

No Advisory 




No Advisory 

No Advisory 


*PFAS: per- and polyfluoroalkyl substances 
*PFOA: perfluorooctanoic acid 
*PFOS: perfluorooctane sulfonic acid 
*PFBS: perfluorobutane sulfonic acid
*HFPO: hexafluoropropylene oxide (also known as GenX) 
*PPT: parts per trillion (the amount equal to one drop of detergent in enough dishwater to fill a string of railroad tank cars ten miles long) 
Health Advisory: The level at which adverse health effects are not anticipated to occur; these are not enforceable. 
MCL: The highest level of a contaminant allowed in drinking water. These are enforceable-meaning drinking water utilities must monitor them and meet them. 


  • 2013: We tested our finished drinking water for six per-fluorinated compounds as part of the EPA’s Unregulated Contaminant Monitoring Rule (UCMR3) program. None of the compounds were detected.

  • 2016: We developed a Source Water Protection Plan, designed to identify, and mitigate threats to the Poudre River and Horsetooth Reservoir. As part of this plan, Utilities conducted a review of potential sources of PFAS in our drinking water supplies. There were no identified industrial sources of PFAS within the watersheds and no past or existing storage facilities were identified through a State records review. It is possible that sources of treated municipal wastewater that are upstream of Horsetooth Reservoir may contribute PFAS from household and commercial sources.

  • 2020: Fort Collins Utilities participated in the Colorado Department of Public Health and Environment’s (CDPHE) PFAS voluntary sampling program. This program was designed to help water providers across Colorado and the communities they serve to determine if PFAS are present in their drinking water. As part of this program, one finished water sample was collected at the point of entry to the Fort Collins Utilities’ water distribution system. Total PFAS at 0.56 parts per trillion (ppt) were detected in the sample, which was below the EPA Health Advisory level of 70 ppt at that time. This result was flagged, indicating that it was below the lab's ability to accurately quantify the result. The detection of PFAS in 2020 could be due to improvements in detection technologies since 2013, rather than the occurrence of a new PFAS source in our watersheds. It might also be due to sample contamination as a result of the ubiquity of the substances in the environment. PFAS analytical results for this program can be found on the CDPHE webpage.

  • 2022: Following the release of the Health Advisories in June, Fort Collins Utilities resampled its two raw water supplies and finished drinking water. No PFAS were detected from those samples. 

Studies have found exposure to PFAS can:

  • Impact the immune system
  • Impact the cardiovascular system
  • Lead to decreased birth weight
  • Lead to cancer

Adverse health impacts are not expected with lifetime exposure levels below the health advisory.

While this is a concern, it is not a crisis. The lower your exposure, the lower your risk. You do not need to stop drinking tap water.

Fort Collins Utilities strives to provide clean, safe, good-tasting drinking water to its customers. We proactively test the drinking water and monitor our watersheds for sources of PFAS, including the Cache la Poudre River and the Colorado-Big Thompson (CBT) project (Horsetooth Reservoir).

PFAS have not been identified in either of the City’s source watersheds; however, it is known that treated wastewater discharges can be a source of PFAS.

Additionally, in some cases, PFAS can occur in drinking water supplies and in finished drinking water (typically localized and associated with a specific facility, e.g., manufacturer, landfill, wastewater treatment plant, firefighter training facility). 

  • Boiling, freezing, or letting water stand does not reduce PFAS levels. 
  • If concerned, reduce exposure by using water treated by an in-home water treatment filter certified to lower PFAS levels.
  • Both the EPA and CDPHE do not recommend bottled water unless it has been treated with reverse osmosis. Bottled water is as likely to contain PFAS as tap water.
  • If you have specific health concerns, consult your doctor.

Chemical compounds, like PFAS, are often manufactured to make life easier, better or safer. But over time, studies may reveal unintended consequences. 

Research and information on PFAS is continually evolving and there is still a lot not known, including:

  • How to remove PFAS from drinking water
  • How to manage and dispose of PFAS
  • How harmful PFAS are to people and the environment 
  • The extent of human exposure to PFAS 
  • How to accurately and precisely detect and measure very low levels of PFAS in air, water, soil, and wildlife 
  • 2000-2002 - PFOS was voluntarily phased out of production in the U.S. by its primary manufacturer.
  • 2006-2015 - Eight major companies phased out their production and use of PFOA, and the chemicals that degrade to PFOA.
  • 2012 - EPA included PFOA and PFOS on the list of contaminants that water systems were required to monitor under the Third Unregulated Contaminant Monitoring Rule. 
  • 2021 - EPA committed to establishing national primary drinking water regulations for PFOA and PFOS.  
  • 2025 - Water utilities will be required to monitor 29 PFAS during the Fifth Unregulated Contaminant Monitoring Rule.


More Information#

National drinking water quality standards are set by the EPA and administered in Colorado by the CDPHE. To express concerns regarding PFAS, you may contact the following:

  1. EPA
  2. CDPHE – Water Quality Division
  3. Local state and federal elected representatives using the Find My Legislator tool at

Did You Know?

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