City of Englewood, Colorado
Home MenuMonitoring PFAS in Water
Updated 4/18/2025
Englewood Water is monitoring for PFAS according to the EPA’s National Primary Drinking Water Regulations. We continue to test and adjust to meet all the EPA’s required PFAS drinking water standards.
What are PFAS?
PFAS, or per- and poly-fluoroalkyl substances, are widely used, long-lasting chemicals which break down very slowly over time. Most human exposure to PFAS chemicals, approximately 90 percent, comes from everyday, purchased items – not drinking water. They have been commonly used for years in many products.
According to the Environmental Protection Agency (EPA), most U.S. manufacturers voluntarily phased out uses of PFAS (such as PFOA and PFOS) in the mid-2000s. However, these chemicals remain in the environment due to the inability to break down, hence the term “forever chemicals.” Scientific studies have shown that long-term exposure to some PFAS may be linked to harmful health effects in humans and animals.
Because of their widespread use and persistence in the environment, many PFAS compounds are found in people and animals all over the world and are present at low levels in a variety of food products as well as water, air, fish, and soil.
Monitoring PFAS in Englewood’s Water
On April 10, 2024, the EPA established a National Primary Drinking Water Regulation for PFAS compounds. The rule identifies the legally allowed level, or Maximum Contaminant Level (MCL), for PFAS compounds in drinking water. Additionally, the EPA suggested (non-enforceable) Maximum Contaminant Level Goals (MCLGs). To comply with this rule, Englewood must monitor drinking water for PFAS and show by April of 2029 that each compound is below its required MCL. See Englewood’s recent PFAS results in the table below. More information about the rule and PFAS can be found on the EPA’s website.
Englewood remains on track to meet the regulations before the compliance deadline. In fact, Englewood is conducting a proactive treatment pilot study and performing voluntarily sampling for PFAS in our water and along the South Platte River.
Englewood PFAS Monitoring Results
(Measured in Parts Per Trillion or ppt. Parts per trillion = Micrograms per liter (ppt = ug/L). One part per trillion corresponds to one minute in 2 million years or a single penny in $10 billion)
|
PFAS Compound |
Maximum Contaminant Levels Goal (MCLG)* |
Maximum Contaminant Level (MCL)** |
July 2024 |
October 2024 |
January 2025 |
April 2025 |
|---|---|---|---|---|---|---|
|
PFOA |
0 |
4.0 ppt |
<4.0 |
<3.8 |
4.0 |
<4.0 |
|
PFOS |
0 |
4.0 ppt |
<4.0 |
<3.8 |
<4.0 |
<4.0 |
|
PFHxS |
10 ppt |
10 ppt |
<3.0 |
<2.9 |
<3.0 |
<3.0 |
|
PFNA |
10 ppt |
10 ppt |
Not detected |
<3.8 |
<4.0 |
<4.0 |
|
PFBS (see last row below) |
No individual MCL*** |
No individual MCL*** |
<3.0*** |
3.6*** |
5.8*** |
3.5*** |
|
HFPO-DA (commonly known as GenX) |
10 ppt |
10 ppt |
<5.0 |
<4.8 |
<5.0 |
<5.0 |
|
Mixtures containing two or more PFHxS, PFNA, PFBS and HFPO-DA |
1 (unitless) Hazard Index*** |
1 (unitless) Hazard Index*** |
0 |
0.0018 |
0 |
*Maximum Contaminant Level Goal (MCLG): The maximum level of a contaminant in drinking water at which no known or anticipated adverse effects on human health would occur, and which allows an adequate margin of safety. Maximum contaminant level goals are non-enforceable health goals.
**Maximum Contaminant Level (MCL): The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs (below) as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards.
***The EPA requires that Englewood monitor for PFBS but has not set a specific maximum contaminant level for PFBS’s regulation. Englewood reports PFBS numbers to the EPA for the Hazard Index risk assessment (last row of the chart) that takes into account cumulative amounts of PFHxS, PFNA, HFPO-DA and PFBS. The annual average Hazard Index must be below 1.
PFAS Frequently Asked Questions:
For Additional Questions and More Information:
If you have any questions or concerns about your tap water that were not answered here, please email utilities@englewoodco.gov or call 303-762-2635.