Lakes and Aquatic Invasive Species

Mantrap Township is home to many natural environment and recreational lakes. (Lake classification is for shoreland development purposes.) To protect lake quality, starting in 2012, the township has funded efforts to shield Big Mantrap, Ojibway, the three Crooked, and Spider lakes from the introduction of aquatic invasive species (AIS). As of 2021, the lakes remain clear.  The annual newsletter contains a report on the township’s efforts and results. Latest updates are listed below. The state only provides funding for Big Mantrap, East Crooked, and Spider. 

2021 Inspection Results

2022 State Funded Hours

Mantrap

Mantrap, commonly referred to as Big Mantrap, is a 1618-acre recreational lake in the northwest corner of the township. Maximum depth is 68 feet. The lake contains the Eurasian watermilfoil, a terrestrial invasive species. For more information on Big Mantrap:  https://www.dnr.state.mn.us/lakefind/lake.html?id=29015100

Ojibway

Ojibway is a 184-acre recreational lake on the western township border. Maximum depth is 22 feet. For more information on Ojibway:  https://www.dnr.state.mn.us/lakefind/lake.html?id=29014900

West, Middle, and East Crooked

West, Middle, and East Crooked are a chain of natural environment lakes in the center of the township. West Crooked is 270 acres with a maximum depth of 50 feet. Middle crooked is 289 acres with a maximum depth of 33 feet. East Crooked is 379 acres with a maximum depth of 96 feet.  For more information on the lakes:

West:  https://www.dnr.state.mn.us/lakefind/lake.html?id=29010103

Middle:  https://www.dnr.state.mn.us/lakefind/lake.html?id=29010102

East:  https://www.dnr.state.mn.us/lakefind/lake.html?id=29010101

Spider

Spider is a 570-acre recreational lake on the southern township border. Maximum depth is 96 feet.  For more information on Spider:  https://www.dnr.state.mn.us/lakefind/lake.html?id=29011700

Resources

MN Dept of Natural Resources: https://www.dnr.state.mn.us

Information on all township lakes:  https://www.dnr.state.mn.us/lakefind/index.html

Aquatic and terrestrial invasive species:  https://www.dnr.state.mn.us/invasives/index.html

County AIS Program