Aldi site stormwater concerns examined; river should not be impacted
Kinnickinnic River Land Trust Executive Director Dave Drewiske received many comments from people concerned about the new Aldi site's proximity to the Kinnickinnic River.
"I'm like 'Well, wait a minute, the city has some of the best if not the best ordinances to protect a river of anywhere in the state, and they are not bending just because we're dealing with an international company," Drewiske said.
He reached out to the city to find out more about the city's stormwater ordinances, and what Aldi has done to comply with those, both during construction and in plans for after the store is built.
He sat down with City Senior Civil Engineer Crystal Raleigh Thursday, Aug. 30 to talk about Aldi's stormwater efforts and the Kinnickinnic River. After the discussion, Drewiske, Raleigh and other city employees toured the Aldi site. The River Falls Journal was also invited to the discussion and the tour.
Drewiske said people have been concerned about runoff from the construction site and the store's soon-to-be completed parking lot getting into the water, and how that might affect the water's temperature.
Large paved areas, like parking lots, can warm water temperatures. When and if that water goes into a river, it can increase a river's temperature, which is not good for trout, Drewiske siad.
Raleigh said Aldi began showing interest in River Falls in January 2017. At that time, they came to the city while in preliminary planning stages.
"They've done this before. They had the best questions," Raleigh said. They asked about stormwater ordinances, parking requirements etc.
Aldi and the city had the first of many development meetings in August 2017, Raleigh said.
When any new development comes to the city, she said, development meetings are held between the city and the would-be developer. One of the things discussed is stormwater.
Raleigh said the process works like this:
Aldi and the city had several meetings and worked together to make sure Aldi's blueprints and construction plans met the city's stormwater ordinances.
After a first meeting, the city will provide a developer a letter summarizing everything discussed. Then the developer will come back with revised plans.
"We go through that process until everyone is satisfied," Raleigh said.
For Aldi, this process lasted from August 2017 to January 2018.
Raleigh said Aldi knew the chosen site was a sensitive spot.
Aldi's initial plan included a stormwater chamber under the parking lot. However, the city requires stormwater on that site to drain away from the river, so Aldi revised its plans.
The city's stormwater ordinances also require the first 1.5 inches of rainfall be able to sink into the ground at any given development site.
At the Aldi site, stormwater will be drawn toward Main Street, away from the river, into a stormwater pond designed for filtration. That means that stormwater will soak into the ground through the pond. When it eventually joins the river, the water will be much cooler, will discharge into the river slowly, and bring much less sediment into the river.
A system is also being put in place to drain water that lands on Aldi's roof into the stormwater pond as well.
"So it should be possible to demonstrate that the developed site will be less impactful on the river than the raw site," Drewiske said. "To me, and I may be geeky about this stuff, but to me ... that's tremendous."
Raleigh said all developers, including Aldi, are required to create a long-term maintenance plan for their stormwater systems.
"You need to maintain it and ensure that it continues to work," Raleigh said.
There is a DNR river-entry site that remains open through construction and will remain open and available to the public after Aldi is open, Raleigh said.