DEVELOPMENT OF REGIONAL AND HYDRAULIC GEOMETRY CURVES FOR THE EASTERN KENTUCKY COALFIELDS

Regional curves and hydraulic geometry curves relate bankfull channel dimensions to drainage area and bankfull discharge, respectively. These curves are used in the natural channel design process to help identify bankfull and to estimate bankfull dimensions of the design channel. Nineteen streams were surveyed to determine their bankfull parameters (cross-sectional area, width, mean depth, discharge, slope, and Manning’s n), along with 27 streams previously surveyed in other studies. The data were used to create regional and hydraulic geometry curves for three hydrologic landscape regions (HLR 9, HLR 11, and HLR 16, individually) in the Eastern Kentucky Coalfields (EKC) as well as the combined region (all HLRs). Results indicated that separating the EKC into HLR improved the R2 of the regional curves. Statistical differences were noted between HLRs with regards to regional curves further suggesting subdivision is beneficial. For hydraulic geometry curves, lack of discharge data limited interpretations and hence recommendations on the need to further subdivide the EKC into HLRs. Results for both regional curve and hydraulic geometry curve analyses suggest that datasets from the EKC may be supplemented using data from other physiographic regions in the U.S. as long as the data are obtained from the same HLR