Philadelphia residents are snatching up bottled water after 8,100 gallons of toxic chemicals spilled into the Delaware River

• Philadelphia officials said the city's water is safe to drink until at least 3:30 p.m. on Tuesday.
• At a press conference on Monday, officials said there was no evidence of contamination.

It is safe to drink tap water in the city of Philadelphia — at least until tomorrow afternoon, local authorities said Monday, stressing that repeated testing has found no evidence of contamination following a chemical spill that occurred upstream just before midnight on Friday.

On Sunday afternoon, Philadelphia residents received an alarming "public safety alert" on their phones urging them to begin "using bottled drinking water" until "further notice." That came after a local company revealed that it had accidentally dumped thousands of gallons of toxic chemicals into the Delaware River.

But authorities almost immediately walked back their recommendation, reiterating that testing had found no contamination in or near a local water treatment facility.

"All the tests so far have been negative," Randy Hayman, commissioner of the Philadelphia Water Department, told reporters. The last round of tests took place on Monday at 4 p.m. local time, he said.

Authorities said the city's water supply is now guaranteed to remain safe for human consumption until at least 3:30 p.m. on Tuesday, extending the earlier deadline of 11:59 p.m. on Monday night. The shifting times relate to the amount of already-tested water currently held in reserve and when that might run should chemicals be detected in or near the intake pipes of the Baxter Drinking Water Treatment Plant, one of three treatment facilities that serve Philadelphia — and the only one supplied by the Delaware River.

"Since the first hours after the incident, the Department of Environmental Protection has been at the facility where the spill originated and will be staying until there is no longer a threat to those impacted in Bucks and Philadelphia counties," Pennsylvania Department of Environmental Protection Acting Secretary Rich Negrin said on Sunday. The department identified the spilled substance as acrylic latex polymer and said that, as of early Sunday, it was no longer leaking from the facility.

In a statement on Monday, Trinseo, a company that manufactures plastic and latex products, said that an estimated 8,100 gallons of the chemicals had leaked from its manufacturing plant in Bristol, just north of the city, where on Friday an unknown amount of those chemicals "entered a storm drain," ultimately flowing into the Delaware River. The plant makes acrylic resins, which can be used as a weather-proofing agent in paint.

Trinseo "voluntarily paused all production operations at the facility," the company said, "to devote its full resources to addressing the release and to conduct a thorough review and analysis of all material-handling processes and equipment at the Bristol facility."

Philadelphia officials said Monday that they will continue to test the water near the Trinseo plant, as well as the Baxter treatment facility, as the chemical plume from the leak makes its way down the river. They said they expect the plume to pass by the facility no later than Thursday.

At a press conference on Sunday, Mike Carroll, deputy managing director for Philadelphia's Office of Transportation, said that at no point did contaminated water enter the Baxter plant, local ABC affiliate WPVI reported.

"There was contamination in the Delaware River, but we shut off the intake to the river and we're operating off of water that was not contaminated," he said. Intakes were briefly reopened early Sunday morning to ensure that minimum water levels were met but "we were able to verify that we brought in water that was not contaminated."

In the meantime, even though officials are expressing optimism — and have walked back their earlier guidance — Philadelphians are stocking up on bottled water and leaving local store shelves bare.

By noon on Monday, when Insider visited an Acme location in Center City, there was no water to be purchased at all — this, even after the grocery store said that it had replenished its Philadelphia stories on Monday morning with supplies from around the region, The Philadelphia Inquirer reported.

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