Sunday, December 16, 2012

Ohio's Glacial Lakes

According to the Ohio Department of Natural Resources, Ohio harbors at least 50,000 ponds and lakes and, of these, only 110 are natural.  The natural lakes are almost all glacial in origin, the product of moraine-dammed streams, glacier-scoured basins or kettle lake formation (see my post of 2-9-08) and are scattered across the Glaciated Appalachian Plateau of northeastern Ohio; a minority are oxbow lakes, which formed during meltwater floods, and are primarily found along large rivers in southern Ohio.  At the end of the Pleistocene, 10,000 years ago, there were many more glacial lakes which, in response to sedimentation and the warmer and drier climate of the Holocene, have become bogs and marshlands; others were drained by human settlers to expand their agricultural fields or to ease construction of roads and rail lines.

This weekend, while visiting family, we stayed in a cottage on Sandy Lake, southeast of Kent.  Covering 90 acres, it is 17th in size on the ODNR list of Ohio's natural lakes.  Like many other natural lakes across the country, this lake has been modified by humans; canals now connect Sandy Lake with other lakes to its north and south, ensuring an adequate water supply for nearby communities.

Though modern residential neighborhoods now encroach on Sandy Lake, it is still bordered by a wooded wetland and upland forest along its southern rim and a fine trail circles the lake, providing access to those wild areas for lakeside residents.  This weekend, flocks of Canada geese, mallards and wintering ducks settled on its calm waters, a bald eagle soared overhead, great blue herons fed in the shallows and a crescent moon reflected from a surface that, while constantly renewed, dates back to the Pleistocene.