Twenty-nine of the more than 2,000 water treatment facilities in Colorado do not meet strict new federal limits on the amount of dangerous “forever chemicals” in their drinking water supplies and it will cost millions to clean those toxins out of the water.

The public water systems that do not meet new standards of 4 parts per trillion for the chemicals, which generally are referred to as PFAS, or perfluoroalkyl and polyfluoroalkyl substances, include the cities of Brighton, Thornton and Keenesburg, as well as water districts in Boulder, Douglas and Jefferson counties, according to a status report from the Colorado Department of Public Health and Environment.

The state report does not specify how much PFAS has been found in those 29 water systems, only that they exceed the “minimum reporting level.”

Denver’s water system does not have current detections of PFAS, but the city’s water has not been sampled since 2020, which is the case for dozens of Colorado water districts, according to state health department’s status report. Denver Water spokesman Todd Hartman said the city’s water is regularly tested for PFAS and its levels are below the new federal standard.

The Environmental Protection Agency for the first time Wednesday announced strict limits on the amount of forever chemicals that will be allowed in the nation’s drinking water systems. The agency estimates that, nationally, 6% to 10% of the 66,000 public drinking water systems may fall short of the new standards.

Testing and public reporting must begin in three years, and utilities must install treatment systems by 2029, according to the EPA’s announcement.

Officials with the state Department of Public Health and Environment said they will work with the various Colorado water districts to help them comply by the federal deadline.

The EPA also announced Wednesday that it would award nearly $1 billion to states so public water districts can test and treat the water they provide to customers.  Colorado is slated to receive $41 million to test and clean drinking water, according to a chart provided by the EPA.

PFAS chemicals are used in products such as firefighting foam, makeup, cookware, carpets, clothes and ski wax to make things stain-resistant or non-stick. They are toxic to humans and can cause cancer, impair fertility and harm the liver. They leach into groundwater, creeks, lakes and canals that supply water for human consumption and agriculture.

Some states already had set standards for forever chemicals in drinking water, but Colorado was not one of them, said Ian Coghill, senior attorney with Earthjustice’s Rocky Mountain office.

“This is a big positive development because there hasn’t been a limit here,” Coghill said. “It’s a big step to say these public water systems have to do this.”

The EPA announced the new limits after years of debate between regulators, environmentalists and water providers, who could be on the hook for costly upgrades to their systems to filter out the chemicals.

While the federal government is providing some money to help water districts come into compliance, it will be a drop in the bucket. And that money is designated for smaller utilities and water suppliers in disadvantaged areas.

Martin Kimmes, Thornton’s water treatment and quality manager, said the city plans to build special systems to pull PFAS chemicals from the water supply by 2027. For now, the estimated cost ranges from $40 million to $150 million, depending on whether the city decides to add a filtration system to one or both of its water treatment plants.

Now the city at least knows the standards it must meet as it plans to build, he said.

“Obviously it’s going to be a financial burden on our ratepayers,” Kimmes said. “But it’s better to be able to know and strategize and know how much it’s going to cost.”

Thornton does not want to shift the entire financial burden onto its customers, Kimmes said.

“We would like the polluters to pay for this or government assistance to help our customers pay for this,” he said. “It’s going to be very expensive.”

Last year, Thornton sued dozens of producers of forever chemicals in U.S. District Court in South Carolina, blaming them for contamination in the city’s drinking water.

Thornton draws water from the Platte River to supply drinking water to more than 155,000 people. The city was forced to close wells that supplied drinking water because of groundwater contamination, Kimmes said. It also blends water from different sources to dilute the PFAS concentrations. Those measures have helped the city drastically reduce its PFAS levels, which are tested monthly.

So far, shutting off wells hasn’t diminished the city’s water supply, but it could be impacted if the region experiences a severe drought, Kimmes said.

The Suncor Energy refinery in Commerce City dumps PFAS into the Sand Creek, which flows into the Platte River, and a new water-pollution permit approved last month by the state health department set for the first time a 70-parts-per-trillion limit on the amount of PFAS the facility can discharge into the creek.

That new water permit still must be approved by the EPA. However, the agency’s new rules won’t impact Suncor because they only apply to the nation’s drinking water supply.

Still, Coghill said he and members of other environmental groups want the state to push Suncor’s PFAS limits even lower because the company contributes to the drinking water pollution. Earthjustice represents three environmental groups in an administrative appeal on the new water permit.

“From our perspective, it’s incumbent on the state to also control the sources of PFAS in rivers and streams to help those cities and towns and to reduce the load on them,” Coghill said.

Colorado for years has been trying to get a handle on how much of the state’s drinking water is contaminated by PFAS after the chemical leached into groundwater, rivers and canals. A groundwater survey in 2019 found contamination in groundwater in metro Denver was much more widespread than previously known.

The Colorado General Assembly is considering a bill this session that would ban the sale of consumer products that contain forever chemicals.

This story was updated on April 11, 2024, to clarify Denver Water’s PFAS testing.

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