Depends where in Michigan you are, and the usual winter precipitation. Here in the Mpls/St Paul area of Minn., the usual is to drain below the outlets, so maybe another 8-10" below what you have. Then let the winter rain/snow melt fill it up. In 30 yrs, I've never been below the skimmers come spring, and never had a risk of overflow either. Your situation may vary, as well as how permeable the cover(s) you end up using are. That solar cover is basically just heavy bubble warp, so between UV exposure from the extended use and the wear/tear from the ice, expect to have to replace it next spring.