HYDRAULIC GEOMETRY RELATIONSHIPS FOR URBAN STREAMS THROUGHOUT THE PIEDMONT OF NORTH CAROLINA

摘要

Hydraulic geometry relationships, or regional curves, relate bankfull stream channel dimensions to watershed drainage area. Hydraulic geometry relationships for streams throughout North Carolina vary with hydrology, soils, and extent of development within a watershed. This urban curve shows the bankfull features of streams in urban and suburban watersheds throughout the North Carolina Piedmont. Ten streams were surveyed in watersheds that had 10% or greater impervious cover. The watersheds, had been developed long enough for the streams to redevelop bankfull features and had no major impoundments. The drainage areas for the streams ranged from 0.4 to 110.3 km~2. Cross-sectional and longitudinal surveys were conducted to determine the channel dimension, pattern, and profile of each stream and power functions were fitted to the data. The study was supplemented with data collected by University of North Carolina at Charlotte and Charlotte Storm Water Services. Urban regional curves are useful tools for applying natural channel design in developed watersheds. They do not, however, replace the need for field calibration and verification of bankfull stream channel dimensions.