Before they were destroyed, Beaver Lake was the largest lake in Indiana, and the Kankakee Marsh was nearly half a million acres of wetland. This was one of the major inland marshes in the country before landowners drained it for farmland. Changing Landscapes of Northwest Indiana examines the massive ecological devastation caused by the destruction of Beaver Lake, the channelization of the Kankakee River, and the draining of the Kankakee Marsh. The book traces early efforts to drain the marsh, leading to the successful completion of the project in the twentieth century, and covers the problems that still exist today.

The consequences were immense and extended beyond the struggle by conservationists to restore or preserve portions of the marsh. The loss of the marsh fostered a century of flooding in the Kankakee Valley and caused decades of conflict with Illinois, which shares the Kankakee River with Indiana. To this day there are ongoing attempts to manage flooding on the river, and residents of Illinois continue to claim that channelization caused severe environmental problems in their state.

Serious and lasting environmental problems have proved intractable. The citizens of Indiana—and their government—made profound and irreversible choices about managing a vast wetland and a river within the state's borders. The story of the conversion of the Kankakee Marsh to farmland is an object lesson in the manifold problems that arise from the imperatives of unrestrained environmental exploitation.