Mapping of sand deposition from 1993 midwest floods with electromagnetic induction measurements

Abstract

Sand deposition on river-bottom farmland was extensive from the 1993 Midwest floods. A technique coupling electromagnetic induction (EM) ground conductivity sensing and Global Positioning System (GPS) location data was used to map sand deposition depth at four sites in Missouri along the Missouri River. A strong relationship between EM reading and probemeasured depth of sand deposition (r2 values between 0.73–0.94) was found. This relationship differed significantly between sites, so calibration by ground-truthing was required for each sand deposition survey. An example of the sand deposition mapping using the EM/GPS system is shown for two 50–60 ha (125–150 ac) sites. Such maps can provide valuable detailed information for developing restoration plans for land affected by 1993 Midwest floods.