WEST ST PAUL, Minn. — Editor's Note: The video above first aired on KARE 11 on March 16, 2022.
Dakota County officials closed access to Thompson Lake at Thompson County Park after thousands of gallons of sewage entered the water.
On May 16, the county initially said that about 50,000 gallons of sewage had seeped into the lake over 24 hours due to sewer line failure at the south end of the lake. However, the county later updated that number to 70,000 gallons.
The leak was stopped on Monday, but people should not use the lake, including for fishing, until further notice.
"Everybody takes for granted flushing their toilet, but there's a lot of work behind the scenes," West St. Paul's Public Works Director Ross Beckwith said Tuesday.
Beckwith explained that the leak started from a valve that was meant to let out air buildup.
"The air release valve in there failed, for whatever reason, got stuck open, and so now you have a small pinhole in this 18 inch pipe, slowly leaking sewage out. that's in the bottom of a manhole that's about 15 feet deep, four feet in diameter so the sewage slowly filled up and it came out the top," he said.
Beckwith said his crews were notified Monday morning and was able to stop the leak within 90 minutes. However, during those 90 minutes, an estimated 70,000 gallons of sewage made its way into the water.
However, Beckwith said he's not too worried about E. Coli levels as the lake water moves continuously.
"The good thing is it hits two of our other city ponds, before it gets even further, so it's getting double, triple treated before it even leaves West St. Paul which is really nice," he said.
Beckwith added that crews tested E. Coli levels twice on Tuesday and will again on Thursday. If levels aren't acceptable by then, he said they will test again on Monday before opening it back up to the public.
The Minnesota Department of Health and Minnesota Department of Pollution Control are both assisting the county with cleanup.
Updates on when the lake will reopen to the public will be posted online.
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