Normandale lake to be drained

Has to be a better way, doesn’t there?

http://m.startribune.com/bloomington-lake-to-be-drained-to-kill-invasive-curly-leaf-pondweed/491609301/

What do you propose?

Shallow watersheds like that bounce back quickly. Can think of the mill ponds in champlin and how nicely they’ve come back.

The fall they drained that the fishing by that spillway was pretty fantastic. I’m not over southside there but all those baitfish may have to go somewhere……

Wonder if anyone’s considered covering the lake in the winter.
5 months without light should be enough to knock down some weed growth.
A few hundred thousand dollars to drain it- how much could a giant tarp cost?

http://www.maisrc.umn.edu/curlyleaf-pondweed

Curly-leaf pondweed is generally the first pondweed to come up in spring, helping distinguish it from other native pondweeds. It dies in the mid-summer, and dead plants may accumulate on shorelines. Its primary means of reproduction is through the production of turions, hundreds of which can be produced by each plant. Turions remain dormant in the sediment through the summer and germinate in the fall. Germination rates can be as high as 80 percent, and turions can remain viable in the sediment for two or more years.

Two or more years of maintaining a large tarp sounds mighty expensive and intrusive to me. When just freezing them over winter should kill immediately.

At 4′ average depth, I can’t imagine much wildlife winters there anyways. Seems like a good option. I’m a bit baffled by the cost, though. Doesn’t seem like it should cost that much.

Here is the cost breakdown to the project. Looks like they went with option 4 because the existing drain pipe is in poor condition and needs to be replaced. The biggest cost is replacing the drain pipe and gate.

I found all the information in this PDF

http://www.ninemilecreek.org/wp-content/uploads/2018-Normandale-Lake-Project-Engineers-Report.pdf

Attachments:

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Tom Anastasi wrote:

Wonder if anyone’s considered covering the lake in the winter.

Curley leaf pond weed grows in the winter and in almost total darkness. Only a little bit of it would need to survive any covering effort and then the lake would be infested again.

Also, as long as they have it drained dry, why not make it deeper? I would think a deeper lake would provide for more fish/wildlife and be more resistant to weeds overtaking it in the future.

Grouse

TheFamousGrouse wrote:

<div class=”d4p-bbt-quote-title”>Tom Anastasi wrote:</div>
Wonder if anyone’s considered covering the lake in the winter.

Also, as long as they have it drained dry, why not make it deeper? I would think a deeper lake would provide for more fish/wildlife and be more resistant to weeds overtaking it in the future.

Makes a lot of sense, and would add a possible FIN lake to the area. However after reading through the Engineers Report and other publications on this project it sounds like because of the relatively small scope of this project they did not need an environmental impact assessment done on this project. I’d imagine your idea would have needed one and raised the price dramatically.