A Year of Portage Lake Levels
Recent data can be found at the Washtenaw County Water Resources Commissioner’s Website.
This chart shows the levels of Portage Lake as measured at the John Fluke Dam over the course of one year. The zero line indicates the court-mandated Summer level of 851.54 feet above sea level. Levels are determined from an electronic gauge at the dam and are reported at noon on each day of the year. Winter levels should be 15- to 18-inches below Summer levels as indicated by the horizontal red lines on the chart.