Evaluation of turfgrid porous pavements for urban stormwater management in Xiamen Island, Southeast China

This paper has investigated the runoff retention and pollution removal effectiveness of a frequently used parking area paved with porous turfgrid in Xiamen Island, southeast China. The results have shown that a turfgrid porous paving area of 72 m² could delay the start time of the runoff generated on it by up to 30 min when rainfall intensity is less than 3.88 mm/h. Although the retention of total suspended solids is only 13.86%, the grass-paved surface can effectively reduce and remove pollutants from the runoff, with the removal of ammonia and NO₃ ⁻-N being significant (at 39 and 76.55%, respectively). In addition, high reductions (>60%) in concentration were found for Zn, Cu, and Pb. However, it was found that pollutant concentrations in the infiltration water samples analysed are higher than in the runoff, which suggests the possible occurrence of pollution accumulation as an emerging pollution source. Furthermore, in 2015 no grass was observed in the pores of the pavement, which suggests that a poor maintenance strategy is in place; with this resulting in the development of a potentially high and concentrated source for pollutants.