The Benefits of a Surface Infiltration Basin

Surface infiltration basins to reduce high floods risks

Infiltration basins are vegetated depressions designed to store runoff on the surface and infiltrate it gradually into the ground. They are dry except in periods of heavy rainfall. They temporarily store, capture, and infiltrate runoff over a period of several days on a level and uncompacted surface. Infiltration basins are typically used for large watershed area of 2 to 20 hectares (according to the Minnesota Stormwater Manual). This technique reduces the stormwater runoff volume in sewers, increases groundwater recharge and provides thermal benefit while being an easy and cost-effective water management solution. Dry surface infiltration basin can be constructed along roads, urban streets, railways car parks, logistic areas, airports, construction sites and service stations. However, hydrocarbon pollution is heavily carried by water runoff from these urban and trafficked roads. This water management solution should therefore include pretreatment before polluted runoff water infiltrates the native permeable soil.