Is porous pavement considered pervious or impervious?

Porous pavement is counted as impervious surface toward the threshold of jurisdiction for the applicability of the Stormwater Management rules and the applicability of the water quality standards. For instance, if 1 acre of porous pavement and 2 acres of standard pavement are proposed on a site, the total impervious surface onsite (for the purpose of determining applicability of the Stormwater Management rules) is 3 acres. However, while the water quality requirements do apply to runoff from porous pavement, the subsurface infiltration facility that is part of standard porous pavement construction will adequately address the water quality requirements of the rules, provided the subsurface infiltration facility is designed in accordance to the Stormwater Best Management Practices manual.  more