State environmental regulators have fined the city of Corvallis for releasing nearly 40 million gallons of untreated wastewater into the Willamette River in two separate incidents last year.
Both incidents involved combined sewer overflows, which occur when pipes carrying mixed rainwater runoff, household sewage and industrial effluent exceed the capacity of sewer systems or treatment plants and spill over into surface waterways.
The Department of Environmental Quality notified the city by certified mail this week of civil penalties totaling $25,800 for violating water quality standards and missing reporting deadlines.
In a news release issued Thursday, Corvallis officials did not dispute that the discharges occurred but said they are considering whether to contest the fines.
According to the DEQ, the first incident happened between March 14 and 16, when roughly 33 million gallons of untreated wastewater entered the river through outfall pipes.
The city called that spill “the result of operator error following a routine procedure to remove debris that had built up on a series of intake screens at a pump station.”
DEQ fined the city $9,600 for that discharge, plus another $7,800 for missing oral and written reporting deadlines for the incident by several days.
The was also was fined $8,400 for an Oct. 22 overflow in which approximately 4 million gallons of combined sewage and storm runoff went into the Willamette instead of the municipal wastewater treatment plant.
In that case, Corvallis officials said, there were “issues with the city’s pumps” following a three-day storm that dumped 3.82 inches of rain on the area.
“In both cases, Public Works staff identified and corrected the errors that led to these overflow events,” Corvallis Utilities Division manager Tom Hubbard said in Thursday’s news release.
“We’ve put new measures in place to make sure these situations don’t happen again.”
Hubbard did not return a phone call on Thursday seeking additional information.
A spokeswoman for the DEQ, however, said the agency is pleased with some of the actions taken in response to the spills.
“DEQ is aware that the city has taken steps to improve employee training and is satisfied with those efforts so far,” said Katherine Benanati, a public affairs specialist for the agency’s western region.
The city has until Jan. 29 to file an appeal of the penalties.