The Lake Pewaukee Sanitary District exists on behalf of the Town of Delafield and it provides the Town with the lake clean-up and harvesting efforts paid by the Town residents in the Lake Pewaukee Sanitary District. The harvesting operation is provided in the City of Pewaukee under an approved yearly contract.
A permit is required from the Wisconsin Department of Natural Resources (WDNR) for any aquatic plant cutting in a lake with a mechanical device. The harvesting operations and lake management efforts follow the recommended plan drafted by the Southeastern Wisconsin Regional Planning Commission in 2004. In 2007 Eco-Resource Consulting, LLC provided a supplementary study and recommendations called “The Aquatic Plants of Pewaukee Lake – Tracking the Past, Looking into the Future”. The WDNR permit reflects the recommendations of these professional aquatic plant management reports. These reports can be reviewed under aquatic plants.
It should be understood that the WDNR will not allow all the aquatic plants to be removed from the lake. Some people would like to see just rippling blue water with a sandy bottom throughout the whole lake. The District and the WDNR understands the value the aquatic plants have on the stabilization of the lake bottom and the value the plants play in the aquatic life that flourishes in the lake. The plants in our shallow small lake hold the bottom sediment from letting loose and creating a “chocolate milk” appearance when the westerly winds blow in. These plants hold habitat for bugs and critters that in turn feed the young of the year fish, turtles and frogs. The plants thrive on nutrients which help reduce the potential for large algae blooms. In a sense the aquatic plants provide the very habitat that make the lake “a balanced living ecosystem”.
The District does however try to keep the aquatic plants down to a level that allows human recreation such as fishing, swimming, waterskiing, wake boarding, sailing, canoeing, kayaking, paddle boarding, pleasure boating and many other activities. This becomes a challenging balance in the shallower areas of the lake, along the shorelines and in some of the bays. Because every lake is different, the management plans are different. What works in one lake won’t necessarily work in another lake. The district used to use chemical treatment for many years and now under the recommendations of the citizen’s advisory committee, the SEWRPC and Eco-Resources, has a harvesting only approach. For more information on chemical treatment go to LPSD & chemical use.
Pewaukee Lake has an eastern basin that was once a swamp. Once the dam was installed the swamp became a 6 foot deep shallow small lake. This lake has a very fertile bottom layer of peat (typical of a swamp) and nutrient rich sediment. This eastern basin will always be heavy with aquatic vegetation both of invasive and native in culture. The goal is to bring back the native species and cut back the invasives such as the Eurasian water milfoil. The WDNR will not allow the District to cut native aquatic plants. So it should be understood that if we could get the lake back to our native species, you could be looking at lake full of vegetation and getting around in some areas would not be easy which was the case back in the 1940’s before the invasive aquatic plant species arrived. See the LPSD History page.
The District starts its harvesting program earlier than any other lake in Wisconsin and runs the program longer than any other lake in Wisconsin in an effort to knock back the invasive species and promote the native species. The challenge becomes what the budget and time allows and the cost benefit of what is being accomplished. The District has been slowly increasing the equipment and labor force in an effort to continuously improve the harvesting operations. Small budget increases are helping increase manpower and more importantly set up the 2nd shift program for years that the cycle provides a peak aquatic plant growth season.
More information
- Lake Equipment
- Pewaukee Lake’s Aquatic Plants
- Aquatic Plant Harvesting
- LPSD & Chemical Use
- LPSD Near Shore Policy
- 1988-2011 Aquatic Plant Removal (.pdf)
- 2021 Lake Weeds [From Newsletter]
- 2013 Lake Operations [From Newsletter]
- 2012 Lake Operations [From Newsletter]
News Links
- JSOnline: Preserving and Protecting Pewaukee’s Waterways (2017)
- Lake Country Reporter: Pewaukee Lake: Pitch in, weed out (2012)
- Case Study: Protecting Lake Pewaukee
- Case Study: Midwest Winter Aquatic Growth