Cleaning methods for pervious concrete pavements

Pervious concrete paving systems increasingly are being applied as environmentally friendly alternatives to traditional impervious pavements. Pervious concrete (PC) systems have been shown to effectively reduce negative environmental impacts associated with impervious pavements, including stormwater pollution, noise, heat island effects, and soil erosion. Keeping PC pavements viable requires maintaining their ability to infiltrate water. The porous nature of PC invites solids such as soil particles and organic matter carried in storm runoff to become trapped in the surface over time, gradually decreasing infiltration rate (IR). The pavement, if left unmaintained, will become increasingly clogged. Since no standardized recommendation for cleaning PC currently exists, water management agencies in some states do not provide stormwater management credit for using PC systems. This research studied the effectiveness of power blowing, pressure washing, and vacuuming, as well as a combination of these methods for restoring IR on small area PC pavements. This study finds that pressure washing and vacuuming are equally effective as initial cleaning techniques, both increasing surface IR by over 90%. Combining vacuuming and pressure washing offers substantial gains over either method alone. These results are important for owners of small area PC pavements who have access to limited equipment.