Hydrology

This refers to surface and groundwater characteristics. Wetlands exhibit long term or periodic inundation by surface waters (over their entire extent, or restricted to streams, channels, ditches, or ponds), or long term or periodic soil saturation. The presence of characteristic hydrology is one of the three parameters used in the federal Section 404 definition of a wetland. (US EPA, Wetlands Regulation Guidebook for New York State, 1993)