than any of the other methods implemented. Probably this is the most accurate slope value since the DEM methods tend to smooth out slopes.
ERRORS AMONG EXTRACTED HYDROLOGIC PARAMETERS
The parameter variation associated with each of the four levels of
parameter extraction is evaluated based on a simple statistical analysis using
standard deviation and coefficient of variation (CV). The coefficient of variation
(CV) is defined as the standard deviation divided by the mean for a group of
The results for drainage area methods of parameter extraction.
showed little variation among the different Results show that drainage area can be
approximated within ± 0.01 mi2 for areas within ± 0.13 mi2 for areas approximately obtained by using automated or traditional
less than approximately 1.6 mi2, and 8.8 mi2. Area measurement, whether methods, will most likely not result in
a large error. This study shows that the for area, determined by Area 1, is 2.07%.
Slope, similar to area, produced fairly consistent measurements for all three study areas. For the largest area, Area 3, slope could be approximated within ± 0.01 as percent slope (a CV of 1.80%). For the small area, Area 1, slope