Nitrogen in Infiltrated Water from Pervious Pavements Under Different Rainfall Regimes and Pollution Build-up Levels

Sustainable urban drainage systems (SUDS) are a nature based solution for best management of rainwater in urban areas. Pervious pavements are one of the SUDS typologies. This study evaluates the water quality filtered by a type of pervious pavement and the influence of the rainfall regime (Atlantic and Mediterranean) and the pollution build-up degree. Total nitrogen (TN) infiltrate concentrations have increased over the study due to the increasing of sediment build-up levels on the pavement surface, with maximum concentrations between 2.7 and 5.0 mg N/l depending on the rainfall regime and the pavement configuration; temperature also influences significantly the leachability of nitrogen. In fact, linear regression models for TN as dependent variable and accumulated mass and temperature have been obtained with a high goodness-of-fit. TN leached over the study represents between 22% and 31% of the total nitrogen present in the sediments accumulated on the pavement surface so the total load is much lower than what would have occurred in an impervious pavement under the same build-up conditions.