Properties of permeable pavement

Properties of permeable pavements.

Properties	Pervious concrete	Porous asphalt	PICP
Typical pavement surface thickness1	5 to 8 inches	3 to 4 inches (thicker for high wheel load applications)	3 inches
Bedding layer1,6	None	1 in. No. 57 stone	2 inches of No. 8 stone
Reservoir layer2,6	No. 57 stone or per hydraulic design>	No. 2, 3, or 5 stone	4 inches of No. 57 stone over No. 2, 3 or 4 stone
Construction properties	Cast in place, seven day cure, must be covered	Cast in place, 24 hour cure	No cure period; manual or mechanical installation of pre-manufactured units
Installed surfacing cost3	$3 to $4/sf	$2/sf	$3 to $4/sf
Minimum batch size	None	None	None
Longevity4	20 to 30 years	20 to 30 years	20 to 30 years
Overflow	Catch basin or overflow edge	Catch basin or overflow edge	Catch basin or overflow edge
Runoff temperature reduction	Cooling at the reservoir layer	Cooling at the reservoir layer	Cooling at the reservoir layer
Surface colors/texture	Range of light colors and textures	Black or dark grey colors	Wide range of colors, textures and patterns
Load bearing capacity5	Handles all vehicle loads with appropriate surface and base/subbase layer material and thickness design	Handles all vehicle loads with appropriate surface and base/subbase layer material and thickness design	Handles all vehicle loads with appropriate surface and base/subbase layer material and thickness design
Surface cleaning7	Periodic vacuuming; replace if completely clogged and uncleanable	Periodic vacuuming; replace if completely clogged and uncleanable	Periodic vacuuming; replace jointing stones if completely clogged and uncleanable
Other issues	Avoid concentrated deicers and winter sanding	Avoid seal coating and winter sanding	Avoid winter sanding
Design reference	ACI Report 522-2010	Hansen 2008 NAPA	Smith 2011 ICPI

^{1 Thickness may vary depending on site and traffic conditions}

^{2 Reservoir storage may be augmented by corrugated metal pipes, plastic arch pipe or plastic lattice crates}

^{3 Supply and install minimum surface thickness only; minimum 30,000 sf with Minnesota 2012 prevailing labor wages. Does not include base reservoir, drainage appurtenances, engineering, or inspection}

^{4 based on pavement being properly maintained. Resurfacing or rehabilitation may be needed after the indicated period}

^{5 Depends primarily on on-site geotechnical considerations and structural design computations}

^{6 ASTM D448 Standard Classification for Sizes of Aggregate for Road and Bridge Construction or ASASHTO M-43}

^{7 Periodic vacuuming frequency determined from inspection, intensity of use, and other potential sediment sources}