Abstract:
In order to study the reduction effect of sponge measures on rainfall runoff and the influence of different rainfall characteristics on sponge measures, a Storm Water Management Model (SWMM) was constructed in Meiguiyuan Community of Guyuan City of Ningxia to simulate the changes of runoff process before and after sponge reconstruction in the study area under different return periods. The results show that: ① The LID measures have obvious effect on the runoff reduction of the drainage at outlet 1, 2, and 3; ② When the return period is 1, 5 and 10 years, the reduction rate of peak runoff and total runoff can reach 25% and 10% respectively, and the reduction rate of peak water level at the outlet can reach 10%. Under different return periods, sponge measures can appropriately delay the occurrence time of flood peaks. However, for large rainfall, sponge measures have limited effect on runoff reduction; ③Under the design rainstorm with different rainfall characteristics, the runoff control effect of sponge measures is quite different. The reduction rate of runoff peak and water level peak increases with the increase of rainfall peak coefficient, the reduction rate of total runoff decreases with the increase of rainfall duration.