Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 1, 2002
Publication Date: April 1, 2002
Citation: SHERIDAN, J.M., MERKEL, W.H., BOSCH, D.D. PEAK RATE FACTORS FOR FLATLAND WATERSHEDS. APPLIED ENGINEERING IN AGRICULTURE. 18(1):65-69. 2002. Interpretive Summary: Improved methods are needed for predicting the characteristic shape of flood flow peaks resulting from large storm events occurring within the Coastal Plain and Flatwoods regions of the southeastern US. To develop this information, forty-six storm events from eight USDA experimental watersheds located in the southeastern Coastal Plain and Flatwoods were analyzed. An equation was developed that relates a factor defining the relative shape of storm flood flows to total watershed drainage area and the slope of the main stream channel. This equation provides a simple, easy-to-use method for estimating watershed storm runoff response characteristics for flatland watersheds. The equation will provide improved design and computer modeling capabilities required for natural resource and environmental planning and management on ungaged, flatland watersheds in the southeastern US.
Technical Abstract: Improved hydrologic design and modeling relationships are needed for predicting storm runoff response from watersheds with low-gradient drainage networks in coastal regions of the southeastern US. Specifically, there is a need for guidelines defining regional, synthetic unit hydrographs that are required for modeling applications on flatland watersheds. To develop this information, forty-six storm events from eight USDA experimental watersheds located in Coastal Plain and Flatwoods regions were evaluated. A relationship was developed relating the watershed unit hydrograph peak rate factor to two readily-measured watershed characteristics, drainage area and main channel slope. This relationship provides a simple, easy-to- use tool that is compatible with hydrologic methods commonly-used for estimating watershed-scale storm response. The relationship will provide improved hydrologic design and modeling capabilities required for natural resource and environmental quality applications on ungaged watersheds in coastal regions of the southeastern US.