An industrial chemical leak killed multiple fish in Portland’s Johnson Creek in late September, Oregon environmental regulators have concluded.

The spill left a 2-mile stretch of dead fish along the southeast Portland creek.

On Friday, the Oregon Department of Environmental Quality notified Precision Castparts Corp. that it had committed “the most serious violations” of Oregon environmental law.

Precision Castparts didn’t immediately respond to an emailed request for comment. Multiple calls to staff at its Johnson Creek facility went to voicemail.

The company spilled almost 400 gallons of sodium hydroxide and other chemicals into the creek between Sept. 17 and Sept. 19, DEQ’s notice says.

Sodium hydroxide is highly corrosive. It can cause deep chemical burns, and it can become flammable when mixed with water. The company also leaked “a smaller amount” of sodium hydrosulfide and sodium chlorite, chemicals that can also harm the environment and people, the state’s notice says.

DEQ is considering enforcement action. It says the company could face financial penalties.

DEQ officials investigated reports of a “foamy discharge” in the creek and fish deaths along the Springwater Corridor bike trail on Sept. 18.

Ten days later, Precision Castparts reported to DEQ that it had “a discharge” into the creek. A week after that, the company told environmental officials the discharge included 394 gallons of chemicals. It said there are no ongoing discharges into the creek.

On Friday, a spokesperson with Oregon Health Authority said there is no ongoing risk to the public.

“The types of chemicals released do not persist or build up in the environment or in the bodies of fish,” Jonathan Modie of OHA said. “The natural flowing of Johnson Creek would have neutralized the corrosivity and diluted the spilled material to safe levels within hours once the discharge stopped.”

Portland-based Precision Castparts is an industrial manufacturer that makes metal castings for aircraft engines and gas turbines. It’s owned by Warren Buffett’s trillion-dollar investment company, Berkshire Hathaway, and has 120 factories worldwide.

Established in the 1950s, Precision Castparts has a decades-long history of polluting water, soil and air in the Portland area.

In 2011, the plant released an orange plume of nitrogen dioxide following a sudden power outage. Some people living nearby had to shelter in their homes.

In 2022, it agreed to pay $22.5 million to settle a class action lawsuit over air pollution from its southeast Portland facility.

That lawsuit stemmed from a 2016 study that found toxic levels of heavy metals in tree moss collected from surrounding residential neighborhoods. The discovery prompted lawmakers to overhaul Oregon’s air toxics regulations and establish the Cleaner Air Oregon regulatory framework.

Oregon Health Authority officials further studied the area with air monitors and soil sampling between 2016 and 2018. They concluded that Precision Castparts’ air emissions posed a low health risk during that time period, though emissions were likely higher in earlier decades.

News Source : https://www.opb.org/article/2026/10/23/deq-says-chemical-leak-killed-multiple-fish-in-portland-creek/