Fire, explosion, uneven pressure: How firefighting foam may have gotten into Harwich water

Frankie Rowley, Cape Cod Times

After a fire on Great Western Road in Dennis Tuesday morning, residents in Harwich were placed under a “do not drink” order Wednesday.

Officials said firefighting foam used for the blaze, which was near the town line, likely contaminated the water supply.

"We're not going to be able to identify it as firefighting foam until the lab results come back, but there's literally nothing else that anybody can come up with that could have caused that," Harwich Fire Chief David LeBlanc said. "We have a viable explanation as to how it got there."

The "do not drink" order was limited to North Harwich at noon Wednesday. Dennis was not affected.

The suspected cause of the contamination, according to a press release from the Harwich Fire Department, is said to be a back-feeding issue while responders were working to control the blaze.

Firefighting foam tops a roadway catch pool off the side of Great Western Road in South Dennis Wednesday morning across the street from the scene of a storage bay fire on Tuesday. Harwich residents in the area were given a water advisory because of runoff from the fire.
Firefighting foam tops a roadway catch pool off the side of Great Western Road in South Dennis Wednesday morning across the street from the scene of a storage bay fire on Tuesday. Harwich residents in the area were given a water advisory because of runoff from the fire.

What happened?

Harwich's Engine 64 initially responded to the fire and began trying to extinguish the blaze with water.

Since engines can only carry a limited supply — 500 gallons — of water, responders resorted to hooking up the engine to a Harwich fire hydrant to increase supply, according to the press release. During the efforts, crews decided to station a Dennis engine at a Dennis hydrant to connect the two supplies and feed more water to Engine 64.

While working to control the blaze, a vehicle’s gasoline tank in the building “let go” and the gasoline caught flame, according to the release. This prompted responders to extinguish the fire with firefighting foam and a total of 25 gallons of foam is said to have been used to extinguish the blaze. The foam, called "Muni Green" is PFAS-free and biodegradable, according to the release.

Due to the difference in water pressure between the Dennis and Harwich systems being fed into Engine 64, the pressure from the Dennis system caused the foam to back feed into the Harwich system, according to the release.

Following the incident, the fire and water departments in Harwich received several reports of foam and bubbles in the drinking water in North Harwich, according to the release. The hydrant used to fight the fire was flushed, but a foam-like substance was visible in the water, causing the fire and water departments to launch their own investigations.

According to LeBlanc, residents in North Harwich should expect to be under the do not drink order through tomorrow, until water testing results come back.

"Hopefully we get an all-clear tomorrow afternoon, and the DEP allows us to (remove) the remaining ban that's in place, but there is the potential that we could not get an all-clear," LeBlanc said. "We won't know until the testing comes back."

Scene of a fire located off Great Western Road in South Dennis on Tuesday in a set of metal work bays. Harwich residents in the area were given a water advisory because of runoff from the fire.
Scene of a fire located off Great Western Road in South Dennis on Tuesday in a set of metal work bays. Harwich residents in the area were given a water advisory because of runoff from the fire.

What happens if you drink the water?

For those who may have ingested the contaminated water, LeBlanc said after speaking with a member of National Foam, the company that creates the firefighting foam, residents would have to have consumed a significant amount of the water to experience issues from the contamination.

"Have you ever drank a glass that had a little bit of soap in it, because it didn't get fully (rinsed) out? And your stomach gets crampy? That's basically what he described it as," LeBlanc said. "You would feel just a little bit of stomach discomfort and that would be if you drank it in quantity. It really should be no impact at all to anyone."

Water distribution for affected residents will run tonight until 7 p.m. at the Family Pantry (133 Queen Anne Road) and tomorrow morning at the Treasure Chest (205 Queen Anne Road). Messaging will be sent out to residents about specific times.

No information was provided on the cause of the fire.

Frankie Rowley covers entertainment and things to do. Contact her at frowley@capecodonline.com.

Thanks to our subscribers, who help make this coverage possible. If you are not a subscriber, please consider supporting quality local journalism with a Cape Cod Times subscription. Here are our subscription plans.

This article originally appeared on Cape Cod Times: How a fire in Dennis may have put foam in Harwich drinking water

Advertisement