Expansive Clay Soils Map

MAP LEGEND

Red Unit contains abundant clay having high swelling potential Blue Part of unit (generally less than 50%) consists of clay having high swelling potential Orange    Unit contains abundant clay having slight to moderate swelling potential Green Part of unit (generally less than 50%) consists of clay having slight to moderate swelling potential Brown Unit contains little or no swelling clay Yellow Data insufficient to indicate clay content of unit and/or swelling potential of clay (Shown in westermost states only)

Page 109 of Extreme Weather Hits Home has a diagram adapted from the “Swelling Clays Map Of The Conterminous United States”
by W.W. Olive, A.F. Chleborad, C.W. Frahme, Julius Schlocker,
R.R. Schneider, and R.L Shuster; 1989

 For additional information showing more detailed regions of the United States:

http://www.surevoid.com/surevoid_web/soil_maps/risk_areas_cons.html

The following link provides a map of areas of expansive clay soil for the City of Ontario, Canada

http://www.ci.ontario.ca.us/index.cfm/22646/32486