Runoff quality prediction from small urban catchments using SWMM

Abstract

Abstract:The RUNOFF block of EPA's storm water management model (SWMM) was used to simulate the quantity and quality of urban storm water runo from four relatively small sites (i.e. 5 . 97±23 . 56 ha) in South Florida, each with a speci®c predominant land use (i.e. low density residential, high density residential, highway and commercial). The objectives of the study were to test the applicability of this model in small subtropical urban catchments and provide modellers with a way to select appropriate input parameters to be used in planning studies. A total of 58 storm events, measured by the US Geological Survey (USGS), provided hyetographs, hydrographs and pollutant loadings for biological oxygen demand (BOD 5 ), total suspended solids (TSS), total Kjeldahl nitrogen (TKN) and lead (Pb), and were used for calibration of the model. Several other catchment characteristics, also measured or estimated by USGS, were used in model input preparation. Application of the model was done using the Green±Ampt equation for in®ltration loss computation, a pollutant accumulation equation using a power build-up equation dependent on the number of dry days, and a power wash-o equation dependent on the predicted runo rate. Calibrated quantity input parameters are presented and compared with suggested values in the literature. The impervious depression storage was generally found to be the most sensitive calibration parameter, followed by the Manning's roughness coecients of conduit and overland¯ow, the Green±Ampt in®ltration parameters and, ®nally, the pervious depression storage. Calibrated quality input parameters are presented in the form of regression equations, as a function of rainfall depth and the number of antecedent dry days. A total of 16 independent rainfall events were used for veri®cation of the model, which showed a good comparison with observed data for both hydrographs and pollutant loadings.

Mapping the Environmental Risk of Antibiotic Contamination by Using Multi‐Criteria Decision Analysis

“…Figure a confirms the positive correlation between % I and overland runoff quantity. The similar impact of this parameter on the runoff production was also demonstrated in previous modelling studies .…”

SWMM Sensitivity to LID Siting and Routing Parameters: Implications for Stormwater Regulatory Compliance

“…Because impervious area is the parameter that is affected by LID placement, it makes sense that it has a large impact on model results as impervious area has been shown to be a sensitive parameter in previous studies (Jewell et al 1978; Liong et al 1991; Barco et al 2008). Results are similar to previous sensitivity analyses for both water quantity and quality, which find subcatchment parameters such as infiltration rates and depression storage to be sensitive (Tsihrintzis and Hamid 1998; Barco et al 2008; Rosa et al 2015).…”

The Application of Low Impact Development Facility Chain on Storm Rainfall Control: A Case Study in Shenzhen, China

“…It is seen that SWMM modeled the runoff volume with acceptable errors. Meanwhile, SWMM can simulate the peak flow values within an acceptable margin of error, as previous studies demonstrated [2,40,41]. In general, the acceptable values of RE, NSE and T pe indicates that the SWMM is suitable for modelling the storm rainfall-runoff in the study site, and the low values of RMSE show that the optimal parameter values of the model have good potential in simulating the runoff processes, using the designed storm rainfall events.…”