City Council Member Meg Tuthill and the city have given developers of an Uptown mixed-use building until Sept. 27 to find a solution to deal with groundwater that they’re pumping from their basement into the lagoon between Lake Calhoun and Lake of the Isles.
If that solution doesn’t satisfy city concerns before the winter freeze, Tuthill says the city is prepared to file a lawsuit against the developers.
“If they do not come up with criteria that is satisfactory to the city we will start a lawsuit,” said Tuthill said.
The developers, Nick Walton and Daniel Oberpriller, are pursuing an injection well to deal with the problem, according to the deadline letter the city sent to their property manager, Lynne Wyffels.
Wylffels was out of the office today, so details of an injection well weren’t immediately clear.
However, Barr Engineering was hired by the city in April to study possible solutions. That report details what an injection well would do: It would take water and pump it back into the aquifer via a 60-foot well.
“In this concept, the pumped groundwater would need to be monitored very closely for any contaminants and a system to bypass the injection well would need to be available in case of contamination,” the report says.
An injection well would cost $1 million to $2 million, according to the report.
Tuthill said the developers have been given notice of the deadline and the criteria needed to satisfy the city. She could not list all the criteria, but said that the building could no longer pump water into the lagoon.
“If we let one developer start putting water into our lake system or our river, we’re suddenly going to be totally out of whack because where do you say no? So you’ve really got to set a precedent.”
Deputy City Attorney Peter Ginder said City Council approval is needed before the city can file a lawsuit.
Construction on the 57-unit building ruptured the groundwater table and now requires the building to pump 100 million gallons of groundwater per year from the garage into the lagoon, according to the Barr report. Last winter, the relatively warm groundwater water created a hole in the ice on the lagoon, and a cross-country skier fell into the open water.
The water flows at 204 gallons per minute and the Department of Natural Resources is concerned that the flow will contribute to flooding during heavy rains.
“With the water being pumped into the lagoon, we really don’t know how that will affect the ecosystem,” said Minneapolis Park Board Commissioner Anita Tabb (District 4). “That’s a really big concern for us.”
The developers hired their own engineering firm, Braun Engineering, to conduct its own testing and analysis.