As of Tuesday, March 27, 2018
MONMOUTH — An electrical fire followed by a hairline crack in a regulator is the culprit for about 1.3 million gallons of partially treated wastewater released to the Willamette River by the city of Monmouth.
The incident happened between 7:35 p.m. on March 16 and noon on March 17, said Mark Landau, city of Monmouth public works.
The wastewater that entered the river was in the last stage of sanitation: the chlorination process.
“Once we had our electrical plug replaced, we noticed the chlorination was still not happening,” Landau said. “So our guys started trouble shooting. We had just gotten one of our regulators from our factory certified repair technicians and it had a hairline crack in it.”
The crack was enough to keep the regulator from bringing chlorine in to complete the process, Landau said.
It was fixed Saturday morning.
Monday, Landau said the Oregon Department of Environmental Quality requested water samples be completed before a press release was sent out.
The samples were collected Monday, and by Wednesday morning, Landau had the results: samples showed an upstream E. coli count of 11 and a downstream E. coli count of 9.
Both samples were collected at boat launches in Independence.
Landau said the test counts colonies of E. coli in a hundred-milliliter sample.
According to the city’s state permit for wastewater, no single sample leaving the plant should exceed 406 organisms in a single milliliter.
“With our normal weekly sampling of our discharge that we’re putting out in the river, our E. coli number is most probably less than 1,” Landau said. “We’re putting cleaner water into that river.”
He said what was released into the river untreated did not contain raw sewage. The water had already undergone multiple steps in treatment, including pulling out the solids and letting small sediment settle out in the lagoons.
Landau said his staff at public works did a great job of trouble shooting, fixing the issue, and getting the system back up and running.