How is a PICP surface cleaned and how often?

The openings in the surface of PICPs will require periodic removal of detritus and sediment trapped by the small sized crushed stone. Dirt is typically removed by a vacuum-sweeping street cleaning machine. Cleaning is done when the pavement surface and detritus are dry and can be loosened by sweeping and vacuuming. The frequency of cleaning will vary with the use of the pavement and position of sediment, leaves, etc. from adjacent areas. Cleaning should be done at least once a year, and the surface monitored during the early life of the pavement so that a regular cleaning schedule can be established.

A North Carolina State University study has shown that the initial surface infiltration rate of PICPs can be as high as 2,000 in./hour (5,080 cm/hour). Other research has shown that near initial surface infiltration rates can be restored through cleaning and replacement of the initial 3/4 to 1 in. (20 to 25 mm) depth of small stones in the openings of PICPs. For highly clogged pavement openings, the stones can be removed with vacuuming and replaced with clean material. This is a distinct maintenance advantage over pervious concrete and porous asphalt pavements.