Role of Infiltration in Storm Water Management

摘要

Runoff from storm drainage systems is affected by the rapid decreases in rates of infiltration which usually occur during periods immediately after rainfall begins. This reduction affects the volumes of runoff and maximum rates of discharge in ways that vary with the rate of decrease and the length of the storm. The effect of the various parameters of infiltration have been determined by means of calculation of runoff from two urban blocks (about 7 acres). A computer program served to calculate hydrographs from assumed conditions for flow from pervious areas, from impervious parts of lots in a developed area and in paved areas. The results provide estimates of the magnitudes of delays and reductions in runoff caused by varying patterns of infiltration.