Floods of June 1953 in Northwestern Iowa prepared under the direction of J.V.B. Wells ; prepared in cooperation with the States of Iowa, Minnesota and with the Corps of Engineers, Department of the Army, 1955

(0195) Floods of June 1953 in Northwestern Iowa prepared under the direction of J.V.B. Wells ; prepared in cooperation with the States of Iowa, Minnesota and with the Corps of Engineers, Department of the Army, 1955. Governor's Office

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Abstract

The floods of June 1953 in northwest Iowa and adjacent areas were the greatest known since settlement of the area. For a few small drainage basins within the flooded area, peak discharges of the June floods may have been exceeded by peaks of previous floods, but the magnitude and areal extent of the June floods is unmatched. The estimated damages in the Floyd River basin, alone, were $25,945,000, of which $23,395,000 were from Sioux City. Fourteen deaths were caused by the flood in the Sioux City area. Outstanding features of the flood were the rapid movement of the flood crest in the Floyd River basin and the magnitude of both peak and volume throughout the flooded area. The floods were caused by heavy rainfall on June 7 for 16 hours, with an intense downpour during the afternoon over an area where rainfall prior to June 7 had been very light. Between Hawarden and Lake Park, Iowa, the rain generally exceeded 7 inches, with a few unofficial measurements of 11 inches; the last rain before the great storm was on June 3 when less than 1 inch of rain fell. In response to the heavy rain, tributaries of the Big Sioux River, Floyd River, Little Sioux River, Des Moines River, and Blue Earth River began to rise rapidly on June 7 and flooding on the main streams of the area followed. Movement of the flood crests was rapid on the Floyd River and flood stages and discharges throughout the flood area generally exceeded the previously known maxima. Elevations of the flood crests were determined at many points along the main streams, mainly by the Corps of Engineers and the Iowa Natural Resources Council, and were made available to the Geological Survey for inclusion in this report. A description of previous floods indicates that the flood of May 1892 was the greatest known flood on Floyd River prior to the greater flood of June 1953; other floods occurred in 1900, 1926, and 1934.