STRATIGRAPHY AND SEDIMENT PROCESSES OF MAUMEE BAY AND THE ADJACENT SHORELINE, WESTERN LAKE ERIE, OHIO

The stratigraphy, hydrology, and sediment processes of Maumee Bay and its shoreline, in western Lake Erie, are being investigated to support planning for a constructed wetland in Maumee Bay State Park (MBSP) that will enhance wildlife habitat and remediate the discharge of coliform bacteria and other contaminants from Berger Ditch into the bay. Maumee Bay is the shallow (generally <1.5 m) embayment where the Maumee River discharges into the southwestern corner of Lake Erie. In the 1800s, the natural drainage of Wolf Creek, which drained the lacustrine plain east of the Maumee River mouth, was diverted into Berger Ditch, through the present MBSP, and into Maumee Bay. Rain events flush water from Berger Ditch that carries high concentrations of fecal coliforms and other pathogens, triggering advisories at the swimming beach at MBSP. Cedar Point and a submerged shoal extending into the bay from the southeast are the depositional end of sand transport from the Lake Erie coast to the east. Other than the sand of that spit platform, Maumee Bay has minimal sand and is dominated by muds from the Maumee River. Probes, Livingston cores, and vibracores from Maumee Bay show a very thin veneer of a few cm to a few tens of cm of fine-sandy mud overlying the eroded surface of a laminated glaciolacustrine clay-silt unit. A few discontinuous sandy shoals with 0.5 m of relief appear locally on this surface in the bay. Observations suggest that most or all of the sediment is either suspended or mobilized along the bottom by wave action during storms. Even so, little of the sand from the constructed beach in MBSP has been lost to offshore transport, and only thin (10-20 cm) muddy sand shoals produced by longshore transport appear downdrift of the beach. Farther offshore near the shipping channel, a basin with water depths greater than 2 m has net deposition of muds alternating with thin (1-2 cm) stringers of fine sand. On land, coring, and electrical resistivity and refraction seismic surveys were used to characterize the deglacial sediment sequence of till and glaciolacustrine clay-silt above the limestone bedrock dipping to the NNE. Water levels in Maumee Bay, Berger Ditch and tributary ditches, and in well clusters in the proposed wetland site are being recorded to evaluate interactions among surface water, ground water, and the bay.