CSO Modeling Using RUNOFF and TRANSPORT Modules of SWMM: Fid-Bau Portal

CSO Modeling Using RUNOFF and TRANSPORT Modules of SWMM

Krabacher, Michael S.

The combined sewer area of Northern Kentucky is located in the northern portion of Campbell and Kenton Counties and covers approximately nine square miles. This area includes 97 combined sewer overflows (CSO) and numerous sanitary sewer overflows (SSO) that discharge into the Ohio River, the Licking River, and Banklick Creek. The separate sewer systems from various municipalities located upstream discharge into the combined sewers. The combination of the combined sewer areas and the separate sewer areas located upstream make up the CSO study area. The goal of the CSO model is to accurately represent the CSO overflow and SSO bypass hydrographs discharged to the receiving streams during a given rain event. The calibrated model is then used to generate yearly CSO loadings through continuous simulation. The model output can be used in conjunction with a stream water quality model to evaluate the effects of different CSO control alternatives on the receiving streams. The software chosen to analyze the study area was the CAiCE software version of the EPA Storm Water Management Model called XP-SWMM32. The model calibration was performed using three months of flow monitoring data at 15 CSO sites and numerous sanitary sewer locations. The CSO monitoring locations were calibrated using the rainfall data record for the entire monitoring period. The CSO basin parameters were estimated using GIS data and combined sewer mapping resources. The model calibration was performed by altering the total catchment area, percent impervious, and the infiltration parameters in RUNOFF. The results indicate that the model simulations accurately estimate the amount of overflow volume monitored at each CSO. The results also indicate that the GIS data can accurately predict the basin parameters for those CSO locations that were not monitored.