The 4th International Conference on Engineering Technology and Applied Sciences (ICETAS), Kyyiv, Ukrayna, 24 - 28 Nisan 2019, cilt.1, sa.1, ss.91
Nowadays, a tremendous increase in impermeable surfaces has been observed due to the rapid urbanization. This situation prevents the recharge of groundwater by stormwater and causes floods by raising the surface runoff and the peak flow. In order to be able to reduce the negative effects of high urbanization, Low Impact Development (LID) implementations have gained attention. Fundamental principles of LIDs involve generation of natural permeable layers around the impermeable areas to allow for infiltration of the storm and snow water reduction of surface runoff and increase in the quality of stormwater. Infiltration trench, green roof, bio-infiltration, permeable pavement and rain garden can be listed among the common LID types. In this study, infiltration trenches are investigated in detail by conducting open-lab experiments. Infiltration trenches have rectangular cross-sections and contain gravel on top of a sand layer. They are typically located along the roads or highways and receive overland flow which develops over the highway surface. They are designed to reduce the peak flow and increase the lag time of peak flow of stormwater runoff. In this study, the hydrological response of infiltration trenches is tested for different values of effective parameters such as gravel type and slope of the trench. In addition, rainfall intensity is also considered as a variable parameter during the experiments. For this purpose, the Rainfall-Watershed-Bioretention (RWB) experimental setup located on the Campus of Istanbul Univesity–Cerrahpaa is employed. A 3.6m long, 1 m wide and 80 cm deep rectangular box made from polyethylene is integrated into the RWB experimental setup to simulate an infiltration trench. The overflow from the infiltration trench and the infiltrated water under the trench are measured under different rainfall intensity values. Finally, the experimental data is compared with the Environmental Protection Agency Storm Water Management Model (EPA SWMM).
Keywords: EPA SWMM, LID, Infiltration Trench, Surface Runoff, Infiltration, Overflow