Background on Rice Lake drawdown needs
The lake is controlled by a dam on Elm Creek. This allows the Rice Lake Area Association (with the help of the City of Maple Grove) to control the lake level when necessary. The lake basin receives water from various sources (creeks, residential and commercial drainage systems, etc.) which cover over 100 square miles in the northwest Hennepin County area. High levels of phosphorous enters the lake from these many sources and, along with the growth of non-native nuisance plants, contributes to accelerated and heavy weed growth. In some situations, this heavy weed growth impedes or halts navigation by water craft and impacts recreational use of the lake.
There has been an on-going increase in the presence of both non-native Eurasian Watermilfoil and Curlyleaf Pondweed since the last whole lake treatment via drawdown was conducted over the winter of 2014-2015. A 2021 Aquatic Plant Study was conducted and showed a high number of both CLP and EWM plants since 2014. We also know that since the last Fish Survey conducted in 2014 shows a disproportionate number of rough fish (common carp and bullhead) to the number of game fish. Each of our project consultants recommended a drawdown with winter aeration to both reduce the CLP & EWM growth and to help the fish population to survive.
How does a Drawdown work?
A drawdown done during the winter months exposes the lake bottom to the elements. A good hard freeze could be very beneficial in stunting the growth of weeds for the next year and possible future years. The native plants are accustomed to the elements and should not be impacted during a drawdown.
How does the Drawdown Process Work?
The procedure for requesting a drawdown is very similar than when last sought in 2014-2015. The Minnesota DNR incorporated a new process in 2012 with these requirements:
- Requesting party (RLAA) must demonstrate the need for the drawdown by following these steps:
- Get at least 75% sign-off from riparian residents (lake/creekshore owners)
- Show evidence that drawdown is needed for non-native plant control.
- Public entity must submit the request (not the lake association)
- That public entity (City of Maple Grove in our case) sponsors the request and submits a request to the DNR for a drawdown permit.
- The DNR asks the public entity to host a public hearing to announce the drawdown.
- MN DNR reviews the request and approves/rejects it
Who Advocates the Drawdown for 2021-2022?
RLAA has received support for conducting a drawdown by the following parties:
- Freshwater Scientific Services (Aquatic Plants consultant)
- Blue Water Science (Fish Survey consulant)
- West Metro Fisheries (DNR)
- Three Rivers Parks District
What is the Current Status for the Drawdown?
As of July 25, both RLAA and the City is working with the MN DNR Area Hydrologist to get the drawdown permit completed and approved. We will keep you informed of the on-going status of this project on this web page.
- 6/8/2021 - Solicited input from RLAA members if they observed enough CLP growth and if it impacted them.
- 7/15 - Based on member input, the RLAA Board of Directors approved the intent to secure a drawdown.
- 6/8 - Confirm the drawdown process with the MN DNR and City.
- 6/8 - Confirm signature process with DNR.
- 7/18 - Collected signatures from the shoreline residents (101 properties).
- 7/22 - Submit list of approvals/rejections to City. Awaiting their approval for next steps.
- 8/2 - City scheduled Public Hearing with LQC for 9/1/2021.
- 8/9 - Sent e-mail reminder to RLAA members to take boats off lake by October 1 with the assumption drawdown will be conducted this fall/winter. Also provided an update on channel dredging project.
- 9/1 - Maple Grove Lake Quality Commission (LQC) approves drawdown request and recommends City Council approve at their 9/7 meeting.
- 9/4 - Sent e-mail reminder #2 to RLAA members to take boats off the lake by October 1.
- 9/7 - City Council approved the drawdown request, which will begin on October 4. MN DNR has already approved this contingent on City Council vote.
- 10/4 - City opened up the bypass below the dam and water is beginning to flow downstream at a substantial rate.
- 10/17 - Volunteers from RLAA Board trench out a channel so the boat ramp bay can drain.
- 10/19 - Lake level is down about 4 feet total, losing about 3" per day.
- 10/30 - Lake level now down about 5 feet total. This should be near the maximum drop (891 sea level down to 886).
- 12/3 - Lake level now down to 885.18, which is about 5.8' below normal. This should be about the maximum the lake can be drawn down.
- 3/19/22 - Lake level begins to rise as watershed snowmelt/run-off enters from Elm Creek.
- 3/23 - Lake level almost 2 feet below normal level as watershed snowmelt/run-off continues to feed Rice Lake. Outlet pipe is running is processing as fast as it can (click here for video). Ice is still present on most of the lake (Elm Creek is ice-free at this time)
- 3/23 - City reports that vandalism has occurred in 2 instances at the bypass manhole by the dam. Please report any occurrences to the MGPD.
- 3/29 - Water level is 1 foot below normal for this time of year. The dam remains open at this time but is unable to keep up with the flow from the watershed.
- 4/9 - Thin ice signs collected from the winter aeration area as the lake ice goes out.
- 4/10 - Ice is completed out (gone) from lake as of today. Dam bypass may be closed now.
- 4/11 - Dam bypass has been closed so the lake can maintain normal levels.
Past Fish Restocking Projects
With the help of the City of Maple Grove, RLAA has stocked more native game fish in both 2015 and 2017. Besides improving the game fish habitat and water quality, these species can feed on the young of both carp and bullhead. Note: All fish stocked were young, except for the 10 pair of adult largemouth bass. Among the species of fish stocked were:
- 10 pair of adult largemouth bass
- fingerling largemouth bass
How low can we go?
- Past drawdowns have experienced these maximum declines in water levels:
Other Comments
- Residents can address erosion problems on their shorelines during this drawdown process.
- Projects like channel dredging can be pursued during a drawdown.
- RLAA recommends boaters have their boats taken off the lake by October 1.
