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Minneapolis could join a Wisconsin city in removing its dams

By BOB SHAW Twin Cities Pioneer Press
MINNEAPOLIS (AP) — The river-liberation movement recently claimed another victory.
In Wisconsin, the city of River Falls is planning to remove two dams in the Kinnickinnic River, similar to a proposal to remove Mississippi River dams in Minneapolis.
The planned dam removal — and the proposed dam removal — reflect a drive to return rivers to their natural, free-flowing state.
In 2018, a record of 88 dams were removed nationwide, according to the river-advocacy group American Rivers.
“Locks and dams are artifacts of the 20th century,” said Whitney Clark, president of the Friends of the Mississippi River. Clark said the dams — many built for milling flour — have outlived their usefulness.
That’s what Mike Page says about the River Falls dams.
Page, a city council member and president of Friends of the Kinni, successfully argued for the demolition of the dams that created Lake George and Lake Louise.
The River Falls City Council in January approved a plan to develop a seven-mile corridor of the river, after the dams are taken down. The lower dam on Lake Louise will be removed when its license expires in 2026, and the upper dam on Lake George will be taken out in 2035, the Twin Cities Pioneer Press reported.
Their removal will create rapids with a 70-foot drop — compared with a 75-foot drop at the three dams in the Mississippi. The estimated cost of removing both dams is $8.5 million, according to city officials.
The lower dam was first built as a wooden dam in 1904 for a flour mill, Page said. Both of the dams were later modified to generate electricity, which they still do today.
Page said that 28 feet of silt has collected in Lake George, and more silt awaits behind the dam at Lake Louise.
The dams have wrecked the water quality of the lakes, he said. “You would not put your toe in either one for $100,” Page said. “There is no vegetation in them.”
The dams hold back water and silt — and fish. Page said the Kinnickinnic is a natural trout stream, but the water behind the dams is usually 5 degrees warmer — too much for the sensitive trout to handle.
In Minneapolis, the first Mississippi dam was built in 1858, and the first flour mill in 1866. The Army Corps of Engineers later added locks and dams to facilitate barge traffic.
But now barge traffic has been suspended, and the Corps is considering selling the Upper St. Anthony Lock, the Lower St. Anthony Lock and Dam, and the Ford Dam, also known as Lock and Dam No. 1.
If these were sold, the new owner could remove them.
It’s hard to say what the dam-free rivers would look like — no one alive today can recall a time before dams.
But Page predicts the Kinnickinnic falls — which gave River Falls its name — will be beautiful. The 70-foot cascade would be a magnet for recreational boaters, he said.
Similar predictions have been made about the removal of the Mississippi dams. Without the dams, water would fall 75 feet over six miles, swirling around a series of boulders and rocks.
“We would have, to my knowledge, something no other city in the U.S. has — a whitewater park running through the heart of town,” said Friends of the Mississippi’s Clark.
A potential drawback to dam removal has been illustrated at another Wisconsin dam.
The dam at Willow River State Park near Hudson released silt during the process of rebuilding it, according Dan Baumann, director of the West Central Region of the Wisconsin Department of Natural Resources.
Silt flowed downstream in 2017, and when the temporary dam was breached in the flooding in March, he said.
The silt collected around the east side of Lake Mallalieu. It filled in the lake around docks, making it impossible for some homeowners to launch boats.
“The lake is ruined because of the massive silt and debris buildup,” said Ric Peterson, who has lived on or near the lake for 68 years.
“I think it could have been better thought out, rather than destroy the top of the pond. The DNR should say, ‘We made a mistake,’ and put it back the way it was,” Peterson said.
But the DNR’s Baumann said silt deposits are natural and unavoidable. “That is nature’s process. That’s water moving down a river, disturbing the banks.”
Silt might be an inconvenience, he said, but damming rivers can hurt plants and animals that have evolved over millions of years to live in free-flowing rivers. Damming the rivers — creating pools of warm, stagnant water — harms river life.
The debate might foreshadow what to expect if the Mississippi dams were removed.
Opponents of the dam-removal idea say the tons of silt behind the dams will be washed downstream, filling in parts of the river in unpredictable ways, and potentially affecting property values.
The two dam sites share another concern — elimination of hydroelectric generation.
The two dams in River Falls combined produce about 375 kilowatts, and the Mississippi generator dams produce 42 megawatts. The hydro-generators are considered a clean, renewable and reliable source of energy.
But in both cases, the amounts are a fraction of the area’s needs.
The River Falls dams produce about 2% of the city’s needs, according to utilities director Kevin Westhouse. The Mississippi generators produce enough for 30,000 homes, which is about 2% of the metro area’s households.
To River Falls’ Page, it’s a worthwhile trade-off. “It’s going to be beautiful,” he said.
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Information from: St. Paul Pioneer Press, http://www.twincities.com