DUBUQUE COUNTY SMART PLAN
Agriculture and Natural Resources Geology and Topography Dubuque County is located in a unique region of the Upper Mississippi River Basin known as the Driftless Area. The Driftless Area covers over 16,000 square miles in the states of Iowa, Illinois, Minnesota, and Wisconsin. The name “Driftless Area� refers to the lack of glacial drift, the silt, clay, sand, gravel, and boulders left behind by continental glaciers. The lack of glacial drift followed by thousands of years of weathering and erosion have resulted in a region of diverse topography, soils, and ecosystems. The steep and rugged landscape is referred to as karst topography. Map 1.1 displays the boundaries of the Driftless Area.
Map 1.1 The Driftless Area
The topography of Dubuque County ranges from gently undulating in the southwest, to hilly and steep in the north and east. Along the Mississippi River and its tributaries, the topography is very steep and rugged, with high limestone bluffs and outcrops. Much Source: The Driftless Area Initiative of the area containing the steep terrain is heavily wooded. Map 1.2 illustrates the varying terrain across the County. Map 1.2 Dubuque County Topography
Source: US Geological Survey
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