WHydrogeology
WAquifer
WBailer (hydrogeology)
WBog pond
WBolson
WEarth's critical zone
WGroundwater sapping
WKarst spring
WLens (hydrology)
WMud-puddling
WOasis effect
WPhreatic zone
WPit water
WRepresentative elementary volume
WSahysMod
WSchlatt (landform)
WSeep (hydrology)
WVadose zone
WWater table
WWoog