Wednesday, December 28, 2016

What would happen to Lake Hiawatha if dams in creek were removed?

Park Board, City enter phase two of investigation and hope to find preferred solution to water issues at golf course

By TESHA M. CHRISTENSEN
If the level of Lake Hiawatha were lowered, would that keep the golf course playable and stop water from entering nearby basements?
Perhaps.
While dredging the lake wouldn’t help lower the level of the lake, planners are studying what would happen if the existing weirs at 28th St. and Hiawatha Ave. were lowered and the creek dredged between the two. (A weir is a low dam built across a river or stream to raise the level of water upstream or regulate its flow.) The outlet of the lake would also need to be modified.
A plus side to a lower lake is that it would offer more flood storage in the area. When there is a large storm and the area around Lake Hiawatha floods, that’s flood storage, pointed out a Minneapolis Park and Recreation Board FAQ on the issue. The bigger the area, the more flood storage there is. A lower lake level would not only provide more flood storage but also might lower flood elevations. The exact impact is not yet known because it hasn’t been studied.
Recently, the Federal Emergency Management Agency (FEMA) adjusted its 100-year flood zone maps, affecting some properties in South Minneapolis. Nearly the entire golf course itself is within the FEMA 100-year floodplain. The level of the golf course could be raised by filling in the low areas.
steffani-ekatrina-michaePhoto right: The Minneapolis Park and Recreation Board (MPRB) and city of Minneapolis are working closely on a solution to the water issues around Lake Hiawatha and the golf course. Park Commissioner Steffanie Musich (at left), Minneapolis Director of Surface Water and Sewers Katrina Kessler, and MPRB Assistant Superintendent of Planning Michael Schroeder answered questions together at the public meeting on Tues., Nov. 29, 2016. (Photo by Tesha M. Christensen)
While that might reduce the need for pumping groundwater, it would also reduce the flood storage, which increases the chances of roads, buildings and houses flooding.
Minneapolis Park and Recreation Board (MPRB) Assistant Superintendent of Planning Michael Schroeder stressed that neither the park board nor the city have the authority to make any alterations to Lake Hiawatha or Minnehaha Creek. Permits and approvals would be needed from regulatory agencies that include the Department of Natural Resources, Minnehaha Creek Watershed District, FEMA, and the Army Corp of Engineers.
“This is a big problem, and this will take a big solution,” said Schroeder during a public meeting on Nov. 29.
Phase one: water being pumped in a big circle
During the first investigative phase, planners gathered data to understand the scope of the problem.
The Minneapolis Park and Recreation Board has been evaluating what to do at the golf course since the large amount of pumping was discovered last fall while planners were working to restore the golf course with $100 million from FEMA.
jeanne-roxannePhoto left: Jeanne LaBore lives near the golf course. She commented that the planning so far seems predicated on the notion that a golf course will be maintained. She questioned the cost of that and suggested that remediation for the homes, such as the installation of sump pumps, might be cheaper. “What’s the best use of that land?” LaBore asked. (Photo by Tesha M. Christensen)
The volume of water being pumped from Hiawatha Golf Course is far greater than allowed by a permit issued by the DNR in 1993 for 36.5 million gallons.
The golf course is currently pumping 263 million gallons of groundwater annually, the amount of water used by a small town in a year, said Schroeder.
Of that, 105 million gallons a year are being pumped in a little circle, seeping from the ponds into Lake Hiawatha and back into the ponds. Of the rest, 17 percent is stormwater run-off, and 50 percent is shallow groundwater. Tests determining this were done from Dec. 31, 2015, to Jan. 4, 2016.
If pumping were to stop, most of the course would be underwater, and it would be shut down.
Planners also realized that turning off the pumps might flood 9-18 homes nearby in the area of 19th Ave. and 44th St. They began meeting with homeowners in June to better understand how deep their basements are and the water issues they face. They also question whether homes farther upstream might also be affected.
Update on investigations 29 March 2016Analysts estimate that some nearby basements are at an elevation of 811.3, which falls below the 812 elevation of the lake. The street is at an elevation of 816.3, while the ponds are at 808.6.
Illustration left: This graph shows the elevations of the land and water of Lake Hiawatha. The dark blue shows existing open water, while the light blue shows the area that falls below the 812.8 elevation of the lake, and would be under water if the pumping were to stop altogether. The white area shows the portion of the golf course that is at 813.8. (Photo submitted)
The elevation of nearby Lake Nokomis, which is separated from the creek, is 816. Planners acknowledge that anything done at Lake Hiawatha will affect Lake Nokomis, and plan to take that into account, as well.
Phase two: what’s next
MPRB is now ready to move on to phase two and pinpoint the best answer for the long-term future of the park land.
“We’re going to move through this process deliberately,” promised Schroeder.
He did stress that the property would remain parkland even if the golf course goes away.
MPRB is working closely with the city. “We know that the park board can’t solve this on our own. We’re going to find a solution together,” said Schroeder.
The solution will not just deal with the golf course, but also the trash flow and ecology of the creek.
“This is a very broad and complex issue, and we want to find a good answer to it,” said Schroeder.
Investigations will evaluate what will happen if the park board continues pumping, reduces pumping, or stops pumping.
“If we’re going to do this for another 100 years, we want someone to say it is good for 100 years,” said Schroeder.
Della Young of Young Environmental Consulting Group has been hired to provide expertise, and another technical consultant is expected to be hired.
A preferred scenario with a clear direction forward and costs will be identified by July 2017.
Jeanne LaBore lives near the golf course. She commented that the planning so far seems predicated on the notion that a golf course will be maintained. She questioned the cost of that and suggested that remediation for the homes, such as the installation of sump pumps, might be cheaper.
“What’s the best use of that land?” LaBore asked.
“We think it’s really important that before you get to that preferred concept, you address the ethics of trying to keep a wetland a golf course,” said resident Connie Peppin.
According to Schroeder, the next community meeting will be in March in order to get more input from residents.
How will the trash issue be solved?
The trash that flows directly into the lake without a filter from a stormwater pipe on the northwest side continues to remain an issue for residents. One attendee encouraged the city to put the stormwater somewhere else, not in the lake.
There are only so many options for stormwater, pointed out Minneapolis Director of Surface Water and Sewers Katrina Kessler. There are hundreds of storm drains in the city. “Ultimately, we are responsible to what is flowing off our properties,” she said. She urged residents to consider other alternatives to salt sidewalks this winter to keep that from entering the watershed.
Roxanne Stuhr remarked that much of the trash pulled out of Lake Hiawatha by volunteers has been styrofoam, and she suggested that the city ban these types of containers.
Another resident suggested that the city begin sweeping streets more frequently. Kessler responded,
“We are looking at that.” The parkways adjacent to lakes and creeks are already swept on a bi-weekly basis in the summer.
“This is a problem that takes many hands to solve,” said Kessler, who pointed out that they’re trying to attack it from multiple facets.
The Friends of Lake Hiawatha are encouraging residents to take part in the city’s Adopt-A-Drain program to keep trash from entering the lake. Volunteers commit to clearing leaves and trash from a drain regularly.
The city piloted a floating curtain in an attempt to catch trash entering the lake from the large storm drain last summer. The curtain netted only four pounds of trash. Compare that to the 2,400 pounds kept out of the city’s drains through the Adopt-A-Drain program, said Kessler.
Seventy residents have adopted over 120 drains in the Standish Erickson neighborhood, with 29 of those draining to Lake Hiawatha.

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