Geomorphic and vegetative characteristics along three northern Virginia streams

Geometry, sediment, and woody-vegetation data were collected from bottomland geomorphic surfaces at valley sections along three gaged perennial streams of northern Virginia. The basins of the streams differ widely in topography and physiography; mean discharges vary from 0.196 to 323 m³ per sec. Prevalent surfaces identified were the depositional bar, the active-channel shelf, the flood plain, and terraces. The stages corresponding to active-channel–shelf levels were equivalent to flow durations of 5% to 13%. Stages corresponding to flood-plain levels were equivalent to discharges with 1.4- to 2.0-yr recurrence intervals. The discharge data and statistical tests of geomorphic-surface, sediment, and vegetative data suggest that the various alluvial features are formed and maintained by hydraulically controlled sorting processes.