Abstract
A GIS Application of Time-of-Concentration Calculations Track: Water, Wastewater, and Stormwater Author(s): Jie Tong Hillsborough County Storm Water Management Model (HCSWMM) is used in the countywide Stormwater Master Plan study. Time of Concentration is one of the Hydrological input data parameter for HCSWMM. This study is conducted specifically to develop the ArcGIS approach by using ArcGIS, Arc Hydro Tool, Arc GIS Spatial Analyst and ModelBuilder. Time-of-Concentration data modeler was created. There were five processes created: Terrain Preprocessing (finding the lowest value in each DEM grid as corresponding sub-basin's outlet point by using Arc Hydro tool), Watershed Processing (Longest Flow Path determination for each sub-basin), Surface Processing (slope generation based on DEM), TOC Segments (determining the length and slope of sheet flow, shallow concentrated flows, and open channel flow), and TOC calculation (calculating the TOC using TOC formulas). ArcGIS is powerful software for storm water management modeling application. This study proves that it is practical for us to apply the GIS. Jie Tong County of Hillsborough Public Works Department 1631 Gray Bark Dr. Oldsmar , FL 34677 US Phone: 813-307-1792 E-mail: tongj@hillsboroughcounty.org |