2017 Spencer Comprehensive Land Use Plan

Spencer, Iowa  2017  Comprehensive Plan

TOPOGRAPHY AND LANDFORMS The topography of Spencer and Clay County can best be summed up by a citation from Northwestern Iowa – It’s History and Traditions 1804-1926 in which the author, Francis Allen, describes northwest Iowa as, “…not a land of lofty peaks and tremendous gashes in the ground, but a gently swelling country…It is not a land of which children are in awe, but which they love, and its expanses of mellow soil, sometimes varied along its water courses by rounded banks and hills, are a constant assurance of thrift, contentment and prosperity.”

Figure 4 - Topography Map of Iowa

The City of Spencer in Clay County is situated upon land where the last of the glacial activity exited the state many centuries ago. Where two glaciers came together it formed a larger ridge called a “median moraine”. Geologist have found abundant evidence that a glacial river left a median moraine here when it encountered another glacier that covered Dickinson County. The average elevation of Spencer is 1,321 feet above sea level. The nationwide average elevation is 1,062 feet above sea level. In comparison, the highest elevation in the State of Iowa is at Hawkeye Point in Osceola County (northwest of Spencer) at 1,670 feet above sea level and the lowest elevation in the State is at 480 feet above sea level in southeast Iowa.

Spencer

Topography map of Iowa with green/blue indicating the lower elevations in the state and red showing the highest elevations in Iowa.

As defined by the Iowa Department of Natural Resources, a “Landscape” is a collection of shapes or landforms. Individual landform shapes reflect the diverse effects of deposits left by glaciers, wind, rivers, and seas in the geologic past. Examples include the loess hills, moraines, kettles, kames, sinkholes, springs, algific slopes, and entrenched valleys. Clay County has many marshes or sloughs across the landscape along with a well-defined drainage system consisting of streams and minor feeders not large enough to be placed on a typical map. These streams and minor feeder creeks drain to the Little Sioux River, which eventually flows into the Missouri River south of Sioux City. Clay County ranges in elevation levels, but Spencer is mostly flat. Spencer lies near the line of the “Northwest Iowa Plains” landform region and the “Des Moines Lobe” landform region. As quoted from the Iowa Department of Natural Resources’ website: The Northwest Iowa Plains Landform “Contains many of the terrain features and geologic materials present in other landforms and is similar in appearance to the Iowa Surface with a uniform low relief. This landform was and still is a relatively treeless, gently rolling landscape. Despite these similarities, the landscape differs from other regions because of a combination of factors…The eastern part of these lands

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NW Iowa Planning & Development