Hydraulic geometry relationships and regional curves are used in natural channel design to assist engineers, biologists, and fluvial geomorphologists in the efforts undertaken to ameliorate previous activities that have diminished, impaired or destroyed the structure and function of stream systems. Bankfull channel characteristics were assessed for 14 United States Geological Survey (USGS) gaged sites in the Inner Bluegrass and 15 USGS gaged sites in the Outer Bluegrass Regions of Kentucky. Hydraulic geometry relationships and regional curves were developed for the aforementioned regions. Analysis of the regression relationships showed that bankfull discharge is a good explanatory variable for bankfull parameters such as area, width and depth. The hydraulic geometry relationships developed produced high R2 values up to 0.95. The relationships were also compared to other studies and show strong relationships to both theoretical and empirical data. Regional curves, relating drainage area to bankfull parameters, were developed and show that drainage area is a good explanatory variable for bankfull parameters. R2 values for the regional curves were as high as 0.98.