A DEM-Based Watershed Model with Spatial Hortonian Infiltration and Run-Off/On

HR: 1340h
AN: H13H-1400 [Abstracts]
TI: A DEM-Based Watershed Model with Spatial Hortonian Infiltration and Run-Off/On
AU: * Meng, H
EM: Huan.Meng@noaa.gov
AF: Colorado State University, Department of Civil Engineering, Fort Collins, CO 80523 United States
AU: Green, T R
EM: Tim.Green@ars.usda.gov
AF: USDA-ARS Systems Research, 2150-D Centre Ave, Fort Collins, CO 90525 United States
AU: Salas, J D
EM: jsalas@engr.colostate.edu
AF: Colorado State University, Department of Civil Engineering, Fort Collins, CO 80523 United States
AU: Ahuja, L R
EM: Laj.Ahuja@ars.usda.gov
AF: USDA-ARS Systems Research, 2150-D Centre Ave, Fort Collins, CO 90525 United States
AB: A physically based, distributed rainfall-runoff-runon model was developed for event-based studies of dynamic watershed processes, including space-time patterns of state variables (e.g., soil profile water storage) and fluxes (e.g., overland flow and infiltration). A routing hierarchy for dynamic runoff and runon is defined over all DEM grid cells using the D-infinity terrain algorithm. Ponding time is computed to handle variable rainfall intensity, the Green-Ampt model is used to calculate infiltration, and the kinematic wave model is used to route Hortonian hillslope runoff and channel flow. The distributed rainfall-runoff model can handle input rainfall, soil parameters, and other watershed properties that vary in space and/or time. The model was first tested against theoretical solutions for idealized overland plane with satisfactory results. After a sensitivity analysis to identify the most significant calibration parameters, the model was calibrated and verified using rainfall and channel streamflow data collected from USDA-ARS Walnut Gulch experimental watershed. Finally, we will demonstrate applications of the model for simulating space-time patterns of fluxes and state variables within a watershed.
DE: 1805 Computational hydrology
DE: 1838 Infiltration
DE: 1839 Hydrologic scaling
DE: 1847 Modeling
DE: 1879 Watershed
SC: Hydrology [H]
MN: Fall Meeting 2005