Lake Management


Our Lake Management Plan is a comprehensive record of historic and existing conditions and influences on Mooney Lake, and is used to identify the goals of the Mooney Lake Association.

Mooney Lake Management Plan (Updated 2013)


Lake Water Monitoring

The Mooney Lake Association partners with the Minnehaha Creek Watershed District in monitoring lake water quality. Monitoring data is used to assign a grade to lakes, indicating the condition of their open water and showing how they compare to other area lakes.

Three water quality measurements (total phosphorus, chlorophyll, and secchi disk) are combined to create each lake’s grade. However, the grade does not reflect the true water quality in a lake body. There are also other factors that contribute to lake condition, including aquatic invasive species (AIS), stormwater runoff, aquatic plants, fisheries, harmful chemicals, and over-use.

The Mooney Lake Association has been testing other parameters since 2012 as a means of determining the true health of our lake.

Lake Monitoring Data (2014-2016)
Lake Monitoring Data (2013)
Lake Monitoring Data (2006-2011)


Lake Level Monitoring

The Mooney Lake Operating Plan for Emergency Pumping was created by the City of Plymouth and the Minnehaha Creek Watershed District (MCWD). MCWD obtains weekly lake level elevation from the Mooney Lake Association, and MCWD instructs the City of Plymouth to activate or deactivate the pump when the upper or lower thresholds are met.

Table 1 (page 3) in the Operating Plan outlines when pumping can start and stop based on the time of year and lake elevations.


Sediment & Invasive Species Survey

A Sediment & Invasive Species survey was conducted to assess the presence of
aquatic invasive species (AIS) in Mooney Lake.

Additionally, the sediment survey evaluated the nutrient release potential of lake sediments (phosphorus, iron, sulfate, pH, organic matter and bulk density), which indicate the growth potential for invasive species in the future.

As of 2014, Curlyleaf Pondweed was the only non-native species known to be present in Mooney Lake.

Aquatic Invasive Species Action Plan (2014)


Aquatic Plant Surveys

In 2011, two aquatic plant surveys were conducted in Mooney Lake to characterize the aquatic plant community of the lake, and monitor the effects of a herbicide treatment for Curlyleaf Pondweed.

Aquatic Plant Survey (2011)


Fishery Management

In 2011 and 2016, fish surveys were conducted by Blue Water Science. Based on the findings in 2011, a Black Bullhead Abatement project was implemented in 2014.

Fish Survey (2016)
Black Bullhead Abatement Report (2014)
Fish Survey (2011)


Winter Aeration System

A winter aeration system was put in place in 2014, to reduce potential winter fish kills, help protect the “shallow lake” ecosystem, and enhance recreational fishing.

Winter Aeration Location