ABSTRACT
The underlying cause for nearly all urban stormwater problems is the loss of the soil’s water-retaining function, because rain water is denied access to it by impervious pavements or rooftops. Porous pavements restore that function by bringing water back into contact with the underlying soil, or emulate that function by filtering and storing water in the pavement structure. Unlike stormwater detention and infiltration basins, which mitigate stormwater problems downstream from urban developments, porous pavements reduce or eliminate the problems at the source by changing the way urban structures are built and the way they operate hydrologically.
