PFAS: What you should know

PFAS Test Results

The Central Brown County Water Authority is a steward of public health and has an established history as a wholesale provider of quality drinking water to more than 95,000 residents in the member communities of Allouez, Bellevue, De Pere, Denmark, Howard, Lawrence and Ledgeview. (In March of 2024, the Village of Denmark began receiving water from the Authority.)  

The Water Authority receives its water through a partnership with Manitowoc Public Utilities (MPU), the entity which draws water from Lake Michigan and then treats it for its customers, including the Water Authority. To ensure public safety, MPU works diligently to meet strict water quality standards set by the U.S. Environmental Protection Agency (EPA) and Wisconsin’s Department of Natural Resources (WDNR).

In recent years, a chemical group called PFAS has been linked to negative health effects. Due to their ability to resist water, oil and heat, PFAS have been used for decades in a variety of items including firefighting foam, cookware, clothing, food wrappers and many other commonly used items. These compounds move freely through the environment and do not break down easily, which has led to PFAS being found almost everywhere.

The EPA has recently adopted new national drinking water standards for six PFAS chemicals that can be found in drinking water.  Under the new rule, EPA set limits for five individual PFAS. No more than 4.0 parts per trillion* of PFOA or PFOS will be allowed in drinking water.  No more than 10 parts per trillion of PFNA, PFHxS, and HFPO-DA (known as GenX Chemicals) will be allowed in drinking water. EPA also set a Hazard Index level for any mixture of PFNA, PFHxS, HFPO-DA, and PFBS.  A hazard index is calculated by comparing the levels of each PFAS to its proposed limit and adding those quotients together. If the hazard index is equal to or above 1, the water may pose a health risk.
New EPA standards graphic 4-15-24
Wisconsin had previously adopted state drinking water standards for two of these six chemicals now regulated by the EPA, but the state standards allow for higher levels of PFAS and will be preempted by the new EPA rules once they take effect in 2029. MPU recently tested for these six compounds, along with 23 others, with results indicating our water is well below the newly adopted limits. The Water Authority and MPU continue closely monitoring developments as more is learned about PFAS.

Of the 29 PFAS substances tested, most were not detected. Six PFAS analytes were detected at low levels including:

  • Perfluorobutanesulfonic acid (PFBS)                                   
  • Perfluorohexanesulfonic acid (PFHxS)
  • Perfluoroheptanoic acid (PFHpA)
  • Perfluorohexanoic acid (PFHxA)
  • Perfluorooctanoic acid (PFOA)
  • Perfluorooctanesulfonic acid (PFOS)

The following tables present the PFAS testing results (provided by an independent laboratory) as compared to the national standards adopted by EPA.

Based on these results, MPU water complies with the new EPA limits and has a hazard index of 0.0602, well below the EPA’s allowable limit. MPU has tested multiple times throughout 2023, with the most current results posted here. In addition, MPU reports all water quality test results to the WDNR and the EPA which are then posted on their websites for public access. 

MPU full spreadsheet
* See “How is PFAS concentration measured?” in the FAQ link on the left navigation bar for an explanation of parts per trillion.

2920 S. Webster Avenue
Allouez, WI 54301-1594
(920) 639-0078