U.S. Geological Survey
Swelling Clays Map Of The Conterminous U.S.

Soil Map of Rhode Island, Conecticut and Massachusetts

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