Pelican Lake Drawdown Update
Posted: Fri Apr 29, 2016 11:20 am
For those that are interested in this project, here is an update from Fred Bengtson (MN DNR):
Yes, the drawdown has been proceeding since December 18, 2014 (1 year and 4 months) at anywhere from a slow to fast rate depending on circumstances like this past fall’s Phase 3 pipeline construction and this winter’s installation of the 3 big pumps.
Here are some facts about the drawdown:
1) We are moving forward with the drawdown on a nearly 4,000 acre Pelican Lake with max flows of about 30 cu. ft./sec (cfs).
2) Early flows ranged from zero to 20 cfs depending on further construction, weather and other factors.
3) Last summer we received about 27”s of rain from May through July.
4) Up until early December 2015 we were flowing water into City of St. Michael Ditch #21 that has less capacity than the current primary route we are using.
5) We are finding out that we will likely need to close down or have very slow flows from January-February due to ice damming downstream and safety issues.
6) I’ve calculated that we have probably moved about 4 billion gallons of water through the structure since Dec. 18, 2014.
7) If we hadn’t been drawing down water on Pelican last summer, water levels would likely be about 12-16” higher than where we started.
8) To date, since Dec. 18, 2014 we have lowered the lake about 1.4 ft.
9) With the new primary route in place we are currently averaging about 1“ /week of lake water lowering. When we get an inch of rain the lake goes up about an inch.
10) We are entering the time of the year again with the most measurable precipitation. Long range forecasts are suggesting a warmer and drier summer, but that is a prediction.
11) We are hoping to have the lake lowered 3-4 ft. by September. If so, we would likely start to use the pumps since lake water levels will be near the bottom of the gravity structure.
12) Low runoff this spring allowed us to gain ground on the drawdown that we normally wouldn’t have.
13) Waterfowl numbers this spring have been more than we have observed for many years.
14) Lake water clarity last summer was high and continues that way. Submerged lake vegetation was dense too last summer.
15) There was some northern pike spearing and fishing this winter, but panfish and crappies are not showing up, although we know there are some in the lake.
16) Good changes are happening, just at a slow rate. We are used to faster drawdowns on smaller shallow lakes. This project will just take time. If we luck out with a drought this summer, if could be a lot faster and vice versa….
Fred