The project involved flow monitoring of five basins using 13 open-channel flow meters over a 12-month period and completion of hydraulic modeling using InfoWorks ICM software. The base flow of the model was developed using dry weather flows from November 2016 with determination of seasonal variation in groundwater elevation. The wet weather flow data was used to emulate the effects of a 24-hour, 10-year rainfall event.
The dry weather, low groundwater base model and the wet weather models were calibrated using the recorded rainfall/flow data from January, February and March 2017. As additional rainfall events occurred and changes in the groundwater elevation were recorded, the wet weather RDII model was continually updated.
The results of the flow monitoring/hydraulic modeling were used to prioritize necessary SSES services, as any flow meter basin which exceeds the groundwater infiltration and stormwater RDII thresholds required inflow source and infiltration source investigations.