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However, the best maintenance practice appears to be prevention. Proper design and construction of pervious concrete should include consideration of the drainage of surrounding areas to prevent the flow of potentially clogging materials onto the pavement surface. Whenever possible, drainage of all unpaved areas should be away from the pervious concrete pavement. Additionally, landscaping materials, such as mulch, should not be stored on the pavement even temporarily.

Your state's regulatory agency and pervious
In 1972, the National Pollutant Discharge Elimination System (NPDES) program was established under the authority of the Clean Water Act. This regulation requires communities and public entities that own and operate a municipal separate storm sewer system (MS4) to obtain an NPDES permit for stormwater discharges. As a part of the permitting process, the permit applicant must establish a best management practice (BMP) for stormwater management. The U.S. Environmental Protection Agency has approved several BMPs for stormwater management, and pervious concrete is among them.

Though pervious concrete is not new, its use in stormwater management is a relatively new concept to the engineering community. As such, projects utilizing pervious concrete are undergoing special scrutiny. Most states include porous pavements, in general, as an accepted BMP but are reluctant to give blanket approval for all projects utilizing pervious concrete. Instead, they provide approval on a case-by-case basis, usually through special provisions to existing regulations.

Tom Evans, promotion director for the Maryland Concrete Promotion Council, explains the process: "If you were going to build a road that crosses a stream, you can either build a bridge or place a culvert with backfill for an at-grade crossing. Either way, you must submit a completed design for approval. You can't just say, 'I'm going to put in a bridge.' The same applies for pervious concrete pavement. You can't just say, 'I'm using pervious concrete' and expect blanket approval. You need to submit a completed design with full details."

To facilitate a smoother approval process, it helps to do your homework. The common concerns of regulatory agencies deal with pervious concrete's freeze-thaw durability, infiltration capabilities and pollutant removal efficacy. Research has been conducted on all of these issues, and the results are readily available.