DEPTH AT WHICH SOIL SATURATION IS REQUIRED IN THE WETLAND 

 HYDROLOGY CRITERION 



1989 MANUAL: 



Requires saturation to the surface at some point in time during the growing 

 season. 



Saturation to the surface would normally occur when, for one week or more, the 

 water table is within: 



. 6 inches of the soil surface in somewhat poorly drained mineral soils, 



. 12 inches of the soil surface in poorly drained or very poorly drained 

 mineral soils, or 



. 18 inches of the soil surface in poorly drained or very poorly drained 

 mineral soils with low permeability (less than 6 inches per hour). 



The above-listed depths to the water table were intended to correspond to 

 saturation to the surface caused by capillary action above the water table. 



PROPOSED REVISED MANUAL: 



Requires inundation and/or saturation at the surface. 



1989 Manual depths to water table as indicators of surface saturation are 

 deleted; replaced by a test for water that can be squeezed or shaken from the 

 surface soil to ensure that capillary action is saturating the soil at the surface. 



