The town of Fort Frances says it was forced to send more than 9-thousand cubic meters of untreated sewage into the Rainy River earlier this month.
The by-pass of the sewage treatment plant happened during two large rainfalls on July 1 and July 4.
Operations and Facilities manager Doug Brown says sump pumps still tied into the system were also a factor.
"We got a little scare here, but we have very little control," says Brown. "If we keep dumping our sump pumps from our ground water weeping tile systems for our foundations into the sanitary sewer system, we're still going to create these problems."
Brown says it was the first time the town has by-passed the plant since March 2006.