HR: 0800h
AN: H21C-0694    [Abstracts]
TI: Automatic Calibration Method for a Storm Water Runoff Model
AU: * Barco, J
EM: ojbarco@ucla.edu
AF: University of California Los Angeles, 5714 Boelter Hall.Civil and Environmental Engineering Dept., Los Angeles, CA 90095-1598, United States
AU: Wong, K M
EM: kmwng@yahoo.com
AF: City of Los Angeles, Los Angeles World Airports, Los Angeles, CA 90045, United States
AU: Hogue, T
EM: thogue@seas.ucla.edu
AF: University of California Los Angeles, 5714 Boelter Hall.Civil and Environmental Engineering Dept., Los Angeles, CA 90095-1598, United States
AU: Stenstrom, M K
EM: stenstro@seas.ucla.edu
AF: University of California Los Angeles, 5714 Boelter Hall.Civil and Environmental Engineering Dept., Los Angeles, CA 90095-1598, United States
AB: Major metropolitan areas are characterized by continuous increases in imperviousness due to urban development. Increasing imperviousness increases runoff volume and maximum rates of runoff, with generally negative consequences for natural systems. To avoid environmental degradation, new development standards often prohibit increases in total runoff volume and may limit maximum flow rates. Methods to reduce runoff volume and maximum runoff rate are required, and solutions to the problems may benefit from the use of advanced models. In this study the U.S. Storm Water Management Model (SWMM) was adapted and calibrated to the Ballona Creek watershed, a large urban catchment in Southern California. A geographic information system (GIS) was used to process the input data and generate the spatial distribution of precipitation. An optimization procedure using the Complex Method was incorporated to estimate runoff parameters, and ten storms were used for calibration and validation. The calibrated model predicted the observed outputs with reasonable accuracy. A sensitivity analysis showed the impact of the model parameters, and results were most sensitive to imperviousness and impervious depression storage and least sensitive to Manning roughness for surface flow. Optimized imperviousness was greater than imperviousness predicted from landuse information. The results demonstrate that this methodology of integrating GIS and stormwater model with a constrained optimization technique can be applied to large watersheds, and can be a useful tool to evaluate alternative strategies to reduce runoff rate and volume.
DE: 1805 Computational hydrology
DE: 1816 Estimation and forecasting
DE: 1846 Model calibration (3333)
DE: 1879 Watershed
SC: Hydrology [H]
MN: 2007 Fall Meeting