Permeable pavement as a stormwater best management practice: a review and discussion

This paper reviews the current status of permeable pavement research and limitations of its applicability. This discusses the influence of design factors such as permeable pavement type, mix design of porous concrete/asphalt, aggregate materials, particle size and distribution, sub-base depth, and layer setting on hydraulic, structural, and environmental performances of the pavement. Findings of this review demonstrate that the uptake of permeable pavement systems as a stormwater best management practice is relatively limited and slow due to lack of in-depth scientific understanding and economic uncertainties. It confirms the necessity of undertaking further research to fill the knowledge gap by providing practical solutions supported by new knowledge and innovations on permeable pavemen systerms. Followings have been identified as challengers and needs for future research on permeable pavement systems: (a) unavailability of cost data and difficulties of estimation of intangible benefits; (b) co-optimising environmental, hydraulic, and structural performances by modifying design; (c) difficulties of simulating actual field condition to investigate the clogging phenomena via laboratory experiments; (d) modelling the relationship of design variations with structural, hydraulic, and environmental performance; (e) developing a standard maintenance procedure to restore infiltration capacity; and (f) improving the bearing capacity of the structure to withstand higher vehicular loads and speeds.