Porous asphalt pavement is one alternative solution to the problem of stormwater drainage from parking and other low traffic density areas.PA used in place of traditional impervious paving materials decreases the total amount of runoff leaving a site, promotes infiltration of runoff into the ground, reduces the amount of pollutants carried to a storm drain or waterway, and aids with reducing peak runoff velocity and volume.

1. POROUS ASPHALT
PAVEMENT
S . DEEPAK
K. SANDEEP
PROFF
K.SURESH
HOD; CMRCET

2. CONTENTS
 STORM WATER MANAGEMENT
 POROUS ASPHALT PAVEMENT
 PAVEMENT DESIGN
 CONSTRUCTION SEQUENCE
 MAINTENANCE OF POROUS ASPHALT
 ADVANTAGES AND DISADVANTAGES

3. STORM WATER
MANAGEMENT
 Storm water is rainwater or melted snow that runs
off streets, lawns and other cities.
 The addition of roads, driveways, parking lots,
rooftops and other surfaces that prevent water from
soaking into the ground to our landscape greatly
increases the runoff volume created during storms.
 EPA expanded the Clean Water Act in 1987 to
require municipalities to obtain permits for
discharges of storm water runoff.
 “Green infrastructure” encompasses approaches
and technologies to infiltrate, evapo transpire,
capture, reduce the rate and/or volume and
remove pollutants from runoff generated on their

4. PARKING LOTS STREETS

5. INTRODUCTION TO POROUS
ASPHALT PAVEMENT
 Porous asphalt pavement is one alternative solution to the
problem of stormwater drainage from parking and other low
traffic density areas.
 PA used in place of traditional impervious paving materials
decreases the total amount of runoff leaving a site, promotes
infiltration of runoff into the ground, reduces the amount of
pollutants carried to a storm drain or waterway, and aids with
reducing peak runoff velocity and volume.
 Porous asphalt is an innovative road surfacing technology,
which allows water to enter into the asphalt mixes beyond its
continuous air voids more than 20%.
 Porous asphalt (PA) also namely open-graded asphalt has
been use as a wearing surface since the 1950s. Its first major
use in Australia was about 1973 and in Japan was about 1987.

6. CLARK TOWN PARKING LAKE GEORGE DRIVE
MORRIS ARBORETUM , PHILADELPHIESSEN ,
GERMANY

7. TYPICAL CROSS SECTION OF
PAVEMENT
 Minimally compacted subbase consisting of undisturbed
existing soil or, in the case of unsuitable base soils, an
imported and prepared base course.
 A 4” (10 cm) minimum thickness of reservoir course with high
air void content maximizes storage of infiltrated water
thereby allowing more time for water to infiltrate between
storms.
 For lower permeability native soils, perforated or slotted drain
pipe is located in the stone reservoir course for drainage.
 The fine gradation of the filter course is for enhanced filtration
and delayed infiltration
 Porous asphalt concrete surface course whose thickness is
based on bearing strength and pavement design
requirements. In most applications, 2½ inches (6.35 cm) has

9. DESIGN OF PAVEMENT
 Consider past uses of the site and appropriateness
of infiltration design and porous pavement.
 Consider the source of runoff. Incorporate
sediment reduction techniques as appropriate.
 Perform site tests to determine depth to seasonal
high water table, depth to bedrock, and soil
conditions, including infiltration capabilities.
Maintain three feet above high water table and two
feet above bedrock.
 Soil infiltration rates of 0.1 to 10 inches/hour (0.5
inches/hour is recommended by EPA).
 The bottom of the infiltration area should be level to
allow even distribution.
 Typically design for stormwater runoff volume
produced in the 6month, 24-hour storm event and

11. CONSTRUCTION SEQUENCE
OF PAVEMENT
 Plan to construct the porous pavement as late as possible in
the construction schedule.
 Protect site area from excessive heavy equipment running on
the subgrade, compacting soil, and reducing permeability.
 Excavate the subgrade soil using equipment with oversized
tires to minimize compaction to soil.
 Use the excess fabric (at least 4 feet) to fold over the stone
bed to temporarily protect it from sediment.
 Place the aggregate stone recharge bed carefully to avoid
damaging the fabric. The aggregate should be dumped at the
edge of the bed and placed in layers of 8 to 12 inches using
tracked equipment and compacted with a single pass of a
light roller or vibratory plate compactor

12.  Install drainage pipes if required.
 When using a stabilizer course, it is important that
the aggregate be sized properly to interlock with
the aggregate in the recharge bed. The stabilizer
course should be placed at a thickness of about 1
inch.
 The porous asphalt should be placed in 1- to 4-
inch-thick lifts following state or national guidelines
for the construction of open-graded asphalt mixes.
 The porous asphalt should be compacted with two
to four passes of a 10-ton static roller.
 Restrict traffic for at least 24 hours after final
rolling.

13. 1.EXCAVATION OF
SOIL
2.
GEOTEXTILE
3. DRAIN PIPE INSTALLATION
4. AGGREGATE INSTALLATION 5.POROUS ASPHALT

14. MAINTENANCE OF POROUS
ASPHALT
 Vacuum twice per year
 Maintain adjacent planted areas
 No construction staging on unprotected pavement
surface pavement surface
 Clean inlets twice per year
 Annual inspections should take place after large
storms, when puddles will make clogging
 Porous asphalt pavements should never be seal
coated or crack sealed. If patching is necessary,
conventional mixes may be used if less than 10%
of the pavement area is affected.
 High pressure washing to free pores in the top
layer from clogging.

15. ADVANTAGES
 Reduction in splash and spray, reduced
aquaplaning
 Reduction in light reflection and headlight glare
 Improvement in Skid Resistance, Reduction in
vehicle rolling resistance
 Cools stormwater temperature during
summertime before discharge and mitigates heat
island effects
 Cost effective technology for stormwater
management, by reducing need for drainage
structures and rights of way
 Recharging of groundwater supplies. Improves
water and oxygen transfer to nearby plant roots

16. DISADVANTAGES
 Porous pavements has a tendency to
become clogged if improperly installed
or maintained.
 Limited use for heavy loading areas.
 Porous pavements are restricted in
cold regions and heavy traffic areas .
 Fuel may leak from vehicles and toxic
chemicals may leach from asphalt or
binder surface and does create the
groundwater contamination.

18. REFERENCES
 http://www.fhwa.dot.gov/pavement/asp
halt/pubs/hif15009.pdf
 www.unh.edu/unhsc/sites/unh.edu...inf
o/unhsc_pa_spec_10_09.pdf
 http://www.asphaltindiana.org/
 http://www.caglaryalcinkaya.com/FileU
pload/ks149954/File/porous_asphalt.p
df
 http://www.asphaltpavement.org/index
.php

19. SAVE
ENVIRONMENT
SAVE LIFE