Some residents of Lake Elmo will notice brown water coming out of their faucets on Wednesday, as the city shuts down one of its groundwater wells.
The Minnesota Department of Health informed the city that higher-than-healthy levels of perfluorochemicals (PFCs) were found in its well No. 1 and water tower No. 1, prompting the shut down.
PFC levels at 45 ppt (parts per trillion) were found. Recommended levels are 35 ppt.
Judging by a Facebook update, residents on and to the east and south of Lake Elmo itself are likely to be affected by the shut down.
They have been told to expect brown water coming from their faucets on Wednesday, and are advised to keep running the water until it turns clear.
The city has had some sporadic brown water issues over the past couple of years owing to aging water mains it's in the process of replacing, city administrator Kristina Handt told BMTN.
It has this advice for residents who encounter it.
"In order to address the brown water issue, city staff has been sporadically flushing hydrants throughout the City. Taking water tower number 1 and well number 1 offline will present an opportunity to flush the system with a higher water pressure to help remedy this issue. The flushing will take place starting at 8:00 AM on Wednesday March 28, 2018 and should be completed by noon. Residents should run their water in the afternoon on the 28th using cold water for approximately ten minutes until the water clears. Flushing the water mains will be an on-going practice. If you continue to see brown water, please contact public works at 651-747-3940. Residents may also see slightly increased water pressure, but this should not be cause for concern."
The shut down will leave the city with just two wells to cover local water supplies, with the Pioneer Press reporting the city shut another well down for the same reason about a decade ago.
Lake Elmo was one of the cities where 3M disposed of wastewater containing PFCs it used to manufacture products like Teflon and Scotchgard over a period of decades.
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