The use of soil maps in the delineation of flood plains

Abstract

Soil maps provide a tool for rapid, low‐cost delineation of river flood plains, based on the difference in morphology between soils frequently flooded and soils free of flooding. Very rare floods along the Mississippi River inundated over 99% of the soils that would be expected to flood but in addition flooded 7% of the terrace soils. Flooding predicted with soils information was compared with flooding predicted with an engineering study for small streams in a mature landscape in southwestern Wisconsin. For a 100‐year synthetic flood an agreement of ±4.5% was obtained. Comparison of flooding with soil types for a small stream in a recently glaciated landscape in southeastern Wisconsin indicated that alluvial soils flood frequently and, in addition, that soils with restricted drainage and soils of fluvial origin also flood frequently. Some of the data are inconclusive, owing to the lack of precise flooding information to serve as a basis of comparison. In areas where man‐made works do not appreciably alter the stream regimen and where extensive flood plain areas must be delineated, it appears that accurate soil maps, properly interpreted, will give a good estimate of areas subject to flooding.

The Use of Soil Surveys to Aid in Geologic Mapping with an Emphasis on the Eastern and Midwestern United States

“…Likewise, in the 1960s, soil surveys were used in Fairfax County, Virginia to determine floodplain limits in support of county planning in areas where engineering or USGS floodplain studies had not been conducted (Coleman, 1963). Cain and Beatty (1968) investigated the use of soil maps to delineate the floodplains of streams in Wisconsin. They found that the soil‐based maps did a good job of showing areas that flooded, but their applicability to return frequency varied.…”

Measuring the Rivers of the Past: A History of Fluvial Paleohydrology

“…Indirect evidence of the frequency of individual prehistoric flood events can be obtained by a number of methods including botanical studies of floodplain vegetation [Sigafoos, 1964, Helley andLaMarche, 1973]; analysis of the degree of soil development on floodplain alluvium [Cain and Beatty, 1968], on flood bars [Bretz et al, 1956;Baker, 1973 Bretz, 1923b]. The anastamosing channel complex that trends northeast to southwest on the eastern side of the scablands is the Cheney Palouse tract referred to in the text.…”

Flood hazard assessment for land-use planning near desert mountains

“…The extent of flooding during severe, infrequent storms can be approximated by comparing evidence from aerial photography and soils maps. The extent of alluvial soils has been shown to be a good indicator of areas inundated by large floods in several areas of the United States (Cain and Beatty 1968). Boundaries shown on preliminary soil survey maps for the north Scottsdale area are only approximate, and the availability of large-scale aerial photography (Table 1) permits more exact delineation.…”