riparian zone

Etymology online
riparian Adj.
"of or pertaining to river banks," 1849, with -an + Latin riparius "of a river bank," from riparia "shore," later used in reference to the stream flowing between the banks, from ripa "(steep) bank of a river, shore," probably literally "break" (and indicating the drop off from ground level to the stream bed), or else "that which is cut out by the river,"