Forever chemicals and the water we drink: What Treasure Valley cities are doing to keep our water safe

The water we drink has a profound effect on our health and safety.

New U.S. Environmental Protection Agency regulations signal great concern that our drinking water, in its current form, may be harmful.

The new regulations will lower the acceptable threshold for two common forever chemicals, which can take over 1,000 years to break down, from a health advisory of 70 parts per trillion (ppt) to a rule of 4 parts per trillion in drinking water.

For other forever chemicals, the EPA set the threshold at 10 parts per trillion.

Research has shown that forever chemicals are harmful, and at lower levels than previously thought. Eleven public water systems in Idaho tested above the new threshold in preliminary testing, including some in the Treasure Valley, according to Tyler Fortunati, the Idaho Department of Environmental Quality’s drinking water bureau chief.

However, those samples were taken ahead of the water receiving any treatment and with different protocols than will be required under the new rule going forward, he said. Additional testing will determine which systems need mitigation.

“IDEQ is going to be continuing to work with our water systems in the state of Idaho to make the appropriate assessments and to help facilitate any technical or compliance assistance that we can,” Fortunati said.

Public water systems have until 2029 to comply with the new rule. A public water system is defined by how many individuals it serves, Fortunati explained. Any system that has 15 service connections, or serves at least 25 individuals daily for at least 60 days of the year, is classified as a public water system, he said.

On Friday, the EPA also announced it would regulate companies that use or manufacture forever chemicals, requiring them to monitor for releases of the chemicals into the environment and fund their cleanup, according to reporting from the New York Times .

THE HARM OF FOREVER CHEMICALS

Forever chemicals, also referred to as PFAS, are very hard to get rid of and have been found in the environment, even in remote areas like Antarctica, said Jenée Cyran, an assistant professor in Boise State University’s Chemistry Department.

One of the most common forever chemicals, Perfluorooctanoic acid, referred to as PFOA, has been classified as a carcinogen by the International Agency for Research on Cancer, and one other, Perfluorooctanesulfonic acid, (PFOS) as a possible carcinogen.

PFOA and PFOS are the two chemicals that are limited to 4 parts per trillion.

Forever chemicals can also cause harm and be toxic to animals and the environment, Cyran said.

In fact, the Environmental Protection Agency has set a goal of zero PFOA or PFOS in drinking water, a move it said “reflects the latest science showing that there is no level of exposure,” without health risks, including cancer. The goal isn’t enforceable.

“When they’re in the waterway, fish or other animals are digesting them as well. And so we’re finding them in a lot of different animals,” Cyran said. “They also can affect plants, since they’re in soil as well. I think they do have some drastic effects.”

These chemicals are used in certain materials, like rain jackets and the coating on skillets, because they can be hydrophobic and help create non-stick surfaces. They are also used in stain-resistant clothing and firefighting foam, according to the EPA.

For those who are concerned, the agency has a list of in-home water treatment filters that can help filter some chemicals out of drinking water. Consumers can also try to find products that are made without forever chemicals, Cyran said.

Scientists have yet to see these chemicals, which are man-made, break down.

“We’re seeing more accumulation getting into different places,” Cyran said. “I think one area people were researching is also, how can we make a different type of material that gives us benefits for what they were doing.”

Scientists including Sarah Wu, an associate professor at the University of Idaho’s Department of Chemical and Biological Engineering, are also working on how to break down forever chemicals.

There are two ways to treat drinking water. The first is to filter out and separate the chemicals from the water, Wu said. But the problem is then you’re left with the chemicals.

One way to destroy the chemicals is to incinerate them at high temperatures. But in recent years, the Department of Defense has banned incinerating PFAS items, which comes with risks for the environment, Wu said.

The reason PFAS are so hard to break down is because of carbon-flourine bonds, one of the strongest chemical bonds, Wu said.

There are different ways to break down bonds but science is still working on the problem.

“There’s no way that’s mature enough yet. That’s why this is still an issue,” Wu said.

MONITORING IDAHO DRINKING WATER

The U.S. Geological Survey has estimated that 45% of tap water could contain one or more forever chemicals.

But prior to last week’s EPA ruling, PFAS were not regulated under the Safe Drinking Water Act, Fortunati said. However, such chemicals were considered emerging contaminants, and some monitoring occurred across the country in different phases to understand the scope of their presence ahead of regulation.

The first phase of monitoring in Idaho ran from 2013-2015, with no PFAS detected, Fortunati said. More recently, in 2020, the EPA provided funding for drinking water testing, including monitoring for PFAS, through the Public Water System Supervision Grant Program.

“When we looked at that funding opportunity, we kind of looked around and said, ‘we don’t even really know if PFAS is present in Idaho, or a potential problem in Idaho,’” Fortunati said.

Idaho was a recipient of the water testing grant, and used it to coordinate with water utilities to conduct sampling, which occurred from April 2021-March 2024, Fortunati said.

In total, IDEQ coordinated with public water systems across Idaho to collect 374 water samples before the water underwent any drinking water treatments, he said.

Public drinking water systems can have multiple sources, and the samples collected represented 12% of active drinking water sources in Idaho, he said. Scientists detected PFAS in 64 of the samples, which corresponded to 11 different public water systems in Idaho, he said.

Detections occurred for water systems mostly in the Treasure Valley, including in Boise, Meridian, Garden City, and Eagle, as well as some smaller systems managed by homeowners associations and different entities, Fortunati said.

Detections elsewhere in the state included one system outside of the Twin Falls area, he said. The city of Coeur d’Alene also had PFAS detections, according to data provided by IDEQ.

Among the systems where PFAS were detected, many measurements didn’t exceed 4 parts per trillion, data provided by IDEQ from the 2021-2024 sampling period shows. And Fortunati emphasized that samples were collected ahead of any type of treatment the water might have undergone prior to being delivered to customers.

Under the new rule, public water systems must monitor for PFAS regularly, sampling water after any treatment has occurred and when the water is ready for distribution. Even detection of PFOA and PFOS at 2 parts per trillion — half of the allowed amount — is enough to require continual monitoring, Fortunati said.

Monitoring involves taking samples once per quarter and averaging the values for the year, he said. So while some PFOA and PFOS measurements could exceed 4 parts per trillion, if other samples had lower PFAS concentrations, the average value for the year could be below the standard 4 parts per trillion, he said.

One type of treatment water systems might use to filter out PFAS is granular activated carbon, Fortunati said. Those tools have a certain lifetime, and will eventually need disposal, which the EPA also plans to regulate, he said.

PFAS IN TREASURE VALLEY DRINKING WATER

Some, but not all, cities in the Treasure Valley had PFAS in their drinking water.

In Boise, Veolia was the largest public water system where PFAS was detected, Fortunati said.

City of Boise staff said the city is evaluating what effect the new regulations would have, and deferred questions about drinking water treatment to Veolia.

Veolia has 83 wells in the Treasure Valley and pulls some water from the Boise River, said Madeline Wyatt, a communications manager for the company in Idaho. It also operates two drinking water treatment plants, one located near the Boise River, and one located in the Columbia neighborhood in Southeast Boise, she said.

The company provides drinking water for most of the city of Boise and two-thirds of the city of Eagle, Wyatt said. The company serves over 250,000 people, according to data reported to IDEQ.

Veolia also has drinking water operations on the East Coast, where PFAS concentrations in drinking water are considerably higher, though the reason why is not yet clear, Wyatt said. Due to the company’s work there and knowing that the EPA was studying the possibility of creating the 4 parts per trillion standard for PFOA and PFOS, the company has begun addressing the issue on the east coast, and plans to do so nationally to comply with the new rule.

On the East Coast, the company already has 30 treatment plants capable of filtering out PFAS, with another 15 being planned, said Adam Lisberg, the company’s senior vice president of communications for North America.

“So this is going to take work … but it’s a problem that can be addressed,” Lisberg said.

Wyatt agreed.

“We’re really comfortable with staying on top of things and making sure that we’re delivering the drinking water our customers expect every single day,” she said.

Of Garden City’s nine wells, testing detected forever chemicals in one of them, Mayor John Evans said. The level of forever chemicals in that well was above the new standard of 4 parts per trillion, a Garden City spokesperson said.

Evans said the city is aware of it and watching to see what treatment techniques are developed over the next few years. Evans said he’s not concerned about continuing to supply safe drinking water for Garden City residents. If need be, the city could always walk away from that well, he said.

“We test our water regularly,” Evans said. “We’ve got a couple years to figure some of this out.”

In Meridian, testing has been ongoing since 2014.

Levels of PFOA and PFOS are between 2.4-3.9 parts per trillion and 1.9-3.9 parts per trillion respectively, according to data provided by the city of Meridian.

Meridian will now have to sample the chemicals known as PFNA and GenX under the new regulations, a spokesperson said. It is unclear if the increased testing will cost the city money.

However, out of Meridian’s 25 wells, forever chemicals have been detected in only four well sites, the spokesperson said.

“Meridian takes its responsibility seriously to deliver clean, safe drinking water to residents,” Public Works Director Laurelei McVey said. “We will continue to sample for PFAS and report these results to our customers as required under these new regulations and do not anticipate any changes or challenges in Meridian with the new federal PFAS regulations.”

Forever chemicals were detected at both Gowen Field, located in Boise, and Mountain Home Air Force Base. Mountain Home AFB did not return a request for comment.

Fortunati said the base had abandoned a well where PFAS was detected. Gowen Field’s drinking water is provided by Veolia, he said.

Firefighting foam, used frequently in the past for training, contains PFAS.

Lt. Col. Christopher Borders said Gowen Field is considered a low-priority site for PFAS because “no drinking water supplies have been identified as affected.” Gowen Field stopped using firefighting foam, which is known to contain forever chemicals, in training in 2016, he said.

“From 2019 — 2020 as part of a nationwide survey, we underwent preliminary assessments and initial site inspections,” Borders said. “As a result of those surveys, Gowen Field was not considered a high risk for soil and/or groundwater contamination.”

The city of Nampa oversees its own drinking water and irrigation water systems, but tests have not revealed any forever chemicals in these samples, staff said.

Nampa has a well that pulls from an aquifer whose water is generated up in the mountains surrounding the Stanley, Pine, and the Featherville areas, where there are no known sources of PFAS, said Senior Public Works Director Tom Points.

“So as long as we protect our drilling standards and how we pump water out of the aquifer, we feel really good that it’s good, clean water,” Points said. The city will continue to comply with PFAS monitoring requirements under the new rule, he said.

The city of Caldwell also did not have PFAS detections during the 2021-2024 survey period, according to IDEQ data. The city’s drinking water comes from a series of wells located throughout the community, according to an annual drinking water report from the city’s website. The city did not provide a comment by press time.