Economics and Feasibility

When site conditions are right, porous pavement can be a cost-effective alternative to conventional dense-graded pavements when the cost of stormwater management is considered. Cahill Associates has compared the costs of porous pavements to other stormwater management options. Generally, the porous pavement has been the less-expensive option.

On a yard-by-yard basis, the asphalt cost is approximately the same as the cost of conventional asphalt. The underlying stone bed is usually more expensive than a conventional compacted sub-base, but this cost difference is generally offset by the significant reduction in stormwater pipes and inlets.

Additionally, because porous pavement is designed to "fit into" the topography of a site, there is generally less earthwork and there are no deep excavations. When the cost savings provided by eliminating the detention basin are considered, porous pavement is an economically sound choice.

Open-graded asphalt mix can be produced in any asphalt plant. Any qualified asphalt contractor can install a porous asphalt pavement system. Certification is not required.

In the photo below, a construction crew "benches" a parking lot's stone recharge bed to fit around a key utilities connection.