Urban Stormwater Infiltration and Soil Drainage

While urban stormwater infiltration is receiving greater attention as a technique for reducing runoff flow and its associated pollutant discharge, the sizing of retention/infiltration basins must take into account the variability in infiltration capacity displayed by the soils present. In the first part of this paper, the temporal infiltration variability in urban soils is studied by focusing on the results of a hydrological monitoring program conducted on urban catchment basins. The second part is devoted to evaluating the effect of soil drainage on infiltration capacity and, as a consequence, on the sizing of retention facilities. These investigations reveal the apparent advantages in simulating the operations of retention/infiltration facilities using actual rainfall data. Such simulations must be able to incorporate both in-soil flows and the effects of their eventual drainage systems.