Infiltration performance evaluation of a 15-year-old concrete grid paver parking area (Italy)

Abstract

The management of urban stormwater needs a wide array of environmentally friendly solutions to safeguard water resources and improve the quality of the urban environment. In that, permeable pavements, a type of sustainable drainage system, are designed to reduce the volume and peak flow of stormwater on-site, improve infiltrating water quality, and combat the urban heat island phenomena. In this study, we tested the infiltration capacity of 15-year-old concrete grid pavers (CGPs) using single ring infiltrometer tests. We investigated how various factors, including location within the parking space, affect infiltration rates. Despite no maintenance and 15 years of operation, the infiltration capacity of the CGPs still exceeds the minimum infiltration capacity of 1.62 mm/min as required in many European regions. This may be due to the presence of soil cracks and the development of plant roots and insect/microorganism activities within the pavement voids. Indeed, this 'living soil system' continuously develops and counteracts the formation of clogging, interacting with the compaction process. Our study demonstrates that incorporating CGPs is effective in addressing emerging challenges associated with urban hydrology. Due to effectiveness and limited maintenance requirements, CGPs could be successfully included in long term climate adaptation measures.