PRE-RESTORATION MONITORING OF A HYDROLOGIC RECONNECTION PROJECT: FATE OF LEGACY PHOSPHORUS
Muskegon Lake is a drowned river mouth lake designated as a Great Lakes Area of Concern (AOC) due to a history of industrial discharges, shoreline alterations, and wetland habitat loss. Property along the AOC’s main tributary, the lower Muskegon River, is under consideration for restoration and hydrologic reconnection to the river to improve fish and wildlife habitat. Past land uses of the restoration area include celery farming, oil and gas exploration, and sulfur deposition from a coal-fired power plant. This pre-restoration monitoring study examines possible phosphorus-related outcomes when reconnecting the property to the natural river. Sediment core isotherms indicated surface (0-10 cm) and subsurface (20-30 cm) depths have equilibrium phosphorus concentrations ranging 0.1-8.4 mg P/L; however, soluble reactive phosphorus in river water was only 0.007 mg P/L, suggesting sediments may act as short-term phosphorus sources to the water column following hydrologic reconnection. Analyses of phosphorus fractionation and river water sediment rewetting experiment are forthcoming. Results will inform a restoration design minimizing phosphorus sediment loading and avoiding negative impacts in downstream Muskegon Lake, which currently meets phosphorus goals for AOC delisting.
Michael Hassett (Primary Presenter/Author), Grand Valley State University - Annis Water Resources Institute, firstname.lastname@example.org;
Maggie Oudsema ( Co-Presenter/Co-Author), Grand Valley State University - Annis Water Resources Institute, email@example.com;
Nicole Hahn ( Co-Presenter/Co-Author), Grand Valley State University - Annis Water Resources Institute, firstname.lastname@example.org];
Alan Steinman ( Co-Presenter/Co-Author), Annis Water Resources Institute-Grand Valley State University, email@example.com;