City officials say limitations set by state law and the DNR on pumping the aquifer are "very clear." Residents beg to differ.
Bloomington city officials and residents who live around Lower Penn Lake are again tussling over how to improve the water quality and appearance of the 32-acre lake.
The city's new draft management plan for the lake left many residents cold when it was presented this week at a neighborhood meeting. In their view, lake levels have dropped to unacceptably low levels since state law limited the use of a well that taps an aquifer to raise the lake's level.
The proposed plan makes it clear that the city and the state are unwilling to permit pumping again from the aquifer beyond 10 million gallons a year. A few years ago, 20 times that much water was routinely added to the lake.
"We would still like to pursue that option, because we don't think that's a done deal," said Lisa McIntire, who lives on the lake and belongs to a resident group that wants water levels kept higher.
But Scott Anderson, a civil engineer with the city, said the limitations set by state law and the Minnesota Department of Natural Resources are "very clear." He said studies also show that pumping is not very effective.
Because the lake bottom is porous, water drains out of the lake almost as fast as it is pumped in, he said.
"To expend a groundwater resource ... we need to know what we're getting out of that, and right now we're not getting very much," Anderson said.
'Absolutely no exception'
Penn Lake was a wetland until 1958, when it was connected to the city's storm-water system. The lake was just 3 1/2 feet deep before it was dredged, stocked with fish and the well was drilled in 1976. A small park area with boat access was added, and the lake was about 8 feet deep at its deepest point.
Since the well was shut off in 2000 except during the winter, water levels have fluctuated. Long expanses of mud along the banks were exposed this summer when it didn't rain, and the water level was down almost 3 feet below the norm in June. This week, the water was down almost 18 inches from its average.
Longtime residents want the lake to look like it did in the 1970s, when green lawns stretched down to the water. McIntire has lived on the lake for 19 years. She said the city's plan "is just a regurgitation of the city's storm-water plan" and doesn't reflect what's unique about the lake.
She argues that the well is needed to maintain the fishery in the lake. Carp, stunted crappies, bluegills and bass live in the lake, which takes in storm water from Interstates 35W and 494.
"If you have a fishery, you can have a pump," she said.
City officials disagree with that interpretation of the law. In a sentence that is underlined for emphasis, a DNR letter to the city supporting the draft plan says: "Please be advised that there is absolutely no exception to this statute [limiting use of groundwater wells] and no variances are possible under any circumstances."
Other improvement options
The city's plan proposes removing accumulated sediment from storm sewer inlets in the lake, which would deepen it in parts, but would be done to improve water quality. That would cost an estimated $40,000. The city's ban on feeding geese and other waterfowl that foul banks and water with their excrement also would be enforced.
Last winter, the city stopped using the well to boost oxygen levels for the fish during the winter, instead using an aerator that recycles lake water. That would continue at a cost of $5,000 a year.
Secondary recommendations include removing rough fish such as carp, building barriers to keep rough fish out, establishing a water-quality monitoring program and treating the lake bottom with alum to bind phosphorus to prevent algae bloom. Sediment ponds that collect storm water before it flows to Lower Penn Lake could be improved.
On the "not recommended" list are two things some residents most wanted: whole-lake dredging and improving the groundwater well.
Anderson emphasized that the strategies in the plan are only proposals that are subject to the city's budget. While projects such as publicizing the waterfowl feeding ban would cost little, measures such as fish barriers would cost $150,000. Projects at Penn Lake would have to compete for funding with those at other lakes and ponds in the city. Much of the funding for such work comes from the city's storm-water utility fee, though some money might be available from sources such as watershed districts.
The plan, which eventually will go to the City Council for approval, may change with input from people who live around the lake and other residents. But Anderson said the goals will remain constant: to enhance the lake's fishery, improve water quality, maintain wildlife habitat and provide flood protection.
Mary Jane Smetanka • 612-673-7380