Yockanookany River near Thomastown, Miss.

Computed roughness coefficient: Manning's n= 0.12 Date of flood: April 12, 1969 Date of photograph: March 28, 1979 Depth of flow on flood plain: 4.0 ft Description of flood plain: The vegetation of the flood plain is primarily trees, including oak, gum, ironwood and many small diameter trees (0.1 to 0.2 ft). The base is firm and has slight surface irregularities. Obstructions are negligible (a few downed trees and limbs). Ground cover and undergrowth are negligible.