Infiltration in Permeable Pavement System

Abstract This study examines a laboratory-scaled infiltration model for the mitigation of stormwater runoff quantity on permeable pavements in a built-up town, Warri in the Niger Delta region. Fast urbanization and further development in traditional impervious asphaltic pavement systems have posed grave stormwater runoff challenges in recent times. The land space has become more impermeable; exposing pavement surfaces to undue hydraulic pressure, flood risks, and other attendant health and environmental impacts. There is a paucity of suitable permeable pavement systems (PPS) models that can promote effective infiltration and detention of stormwater runoffs at peak flash floods around pavement infrastructures and corridors. For this study a laboratory-scaled interlocking permeable pavement full depth of 600mm length x 600mm breadth x 1200mm depth rigs of three permeable interlocking concrete pavement full depth matrix; PICP Rig types 1, 3, and 4 and a fourth (control) made of assembled hot rolled segmented asphalt pavement (HRSA) Rig type 2 were exposed to simulated rainfall head and vertical infiltration process monitored for 30 minutes in stepwise time of 3minutes with several runs of the experiment. The highest infiltration performance of 46.20% from PICP type 3 (which had the most porous aggregates) was observed following the absence of fines used in the volumetric mix ratio in pavement pavers. The experimental results and the regression predicted model have great correlation coefficients of (R2) between 0.9771 and 0.9918 respectively. Infiltration rates of between 3.67mm/min and 4.67mm/min were obtained. Pavement rigs PICP types 3 and 1 had more fines and lesser porous aggregates, which showed infiltration performance of 23.15% and 20.04% respectively, and lower than PICP type 4. Pavement Rig 2 HRSA pavements which served as control in the study showed the lowest infiltration performance and earlier ponding suggesting that a more porous mix supports the best infiltration performance. The model is applicable in the design of PPSs including the estimation and management of stormwater flash floods peaks and flow schemes for developing countries, especially in the wet Niger Delta region.