Example of Permeable Pavement for Stormwater Management
A type of concrete that allows water to pass through the pavement is one strategy designers and engineers are using to better manage stormwater. Recently, the City of Toledo used this method to solve a tricky problem. The city’s Division of Sewers and Drainage had been called to the Dexter Street alley several times for sanitary sewer repairs. Eventually workers determined that the sanitary sewer was collapsing. Engineering Services was called to design a replacement. To make things more complicated, engineers found that two stormwater catch basins in the alley were connected to the sanitary sewer. Combined sewers are a problem in many older cities including parts of Toledo which has been ordered by the EPA to separate the systems. The sewer design for the alley now had to include sewer separation. These catch basins were also not positioned well; they were on the north and south corners of the alley while the slope was to the east. Garages built along the alley limited some construction options. To solve this range of problems, pervious concrete was a good solution. Now, stormwater drains through the pavement and into a stone drainage bed. Perforated pipe in the drainage bed collects the water and pipes it to stormwater catch basins on a nearby street. This is the first full alley in the City of Toledo paved with a pervious surface.
While pervious concrete is not appropriate in all applications, in this case it was part of a stormwater management solution that improved the appearance and the operation of the alley.
Photos Courtesy of Toledo Division of Environmental Services