The COVID‐19 pandemic delayed most sampling plans in 2020; however, CSMI‐related sampling plans were adjusted to be carried out in 2021. This prospectus describes planned activities for Lake Michigan, to be completed by scientists from the NOAA Great Lakes Environmental Research Lab (NOAA‐GLERL), the US Geological Survey Great Lakes Science Center (USGS‐GLSC), the US Environmental Protection Agency’s Great Lakes National Program Office and Office of Research and Development (EPA‐ GLNPO and EPA‐ORD, respectively), and university partners. These activities are based on research priorities identified by the Lake Michigan Partnership Working Group, which comprises representatives from federal, state, and tribal agencies in Michigan, Indiana, Illinois, and Wisconsin.