drainage hidden on the edge of an asphalt road drainage system hidden in a perforated concrete gray curb. the water along the enti

asphalt cleaning clever concrete construction curb drain drainage edge enti entire gaps gravel gray gutter hatch hidden highway hole holes inside kerb landscaping lid low maintenance metal new outdoor parking perforated perforation permeability point rain road roadway seepage sewage sewing side sidewalk site slotted steel street surface system transportation urban water