Assessing the Flow Reduction of Low Impact Development Controls in a Residential Setting

The widespread development in recent years has resulted in the expansion of impervious surfaces, allowing runoff to accumulate and cause flooding issues. To reduce the impacts of runoff accumulation, the concept of low impact development (LID) has been adopted to restore the hydrological balance of urbanized areas. The objective of this study was to assess the flow reduction of the LID combinations in a residential park in Cavite, Philippines using Stormwater Management Model (SWMM). The 90th percentile of historical rainfall from the years 1975-2019 was used in the assessment. The bioretention (BR), infiltration trench (IT), and permeable pavement (PP) LID controls, which captured 43%, 42%, and 14% of the park area respectively, were selected for implementation alongside their different combinations. Results of this study have shown that most LID scenarios reached their maximum reduction capability once it takes up around 20-40% of the total available area. The highest reduction, at around 90%, was attained by the BR+IT+PP scenario. The use of the PP scenario, however, only yielded a 20% flow reduction due to its small capture area. Implementing LID controls in urbanized locations can help in reducing runoff buildup, thereby alleviating the potential impacts of flooding.