Permeable Paving
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Transcript Permeable Paving
Permeable Paving
Low Impact Development (LID)
Low impact development (LID) is an approach to
managing stormwater runoff to protect water quality
Permeable Pavements
Permeable pavements are recognized as a Best
Management Practice (BMP) by the U.S. Environmental
Protection Agency
A cornerstone of low impact development (LID) design
Non-Permeable Pavements
Increased runoff
Deprives groundwater
Pollutants
Non-point source
Non-Permeable Pavements
1990s average was about 30,000 miles of paving per year
Parking lots affect microclimates of city climates
Non-Permeable Pavements
U.S. federal law mandates that states control water
pollution in runoff through the National Pollutant
Discharge Elimination System (NPDES)
Advantages of Permeable Pavers
Increases the water quality
Increases groundwater
Reduces installation costs of drainage system
Reduces storm water runoff
Reduces flooding
Reduces erosion
Permeable pavers
Initially, infiltration is
over 50-75in/hr.
Reduce by around 50%
in the first 5 years.
Over a 20-year period,
designed to achieve and
maintain a consistent
3in/hr infiltration rate
Permeable pavers
No sand used in joints
Clog pores
Permeable pavers
http://www.youtube.com/watch?v=xBTYFo2z9HY&featur
e=related
Permeable pavers
Cleaning should be done at least once a year
Removed by a vacuum-sweeping street cleaning machine
Permeable interlocking concrete pavements
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. 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. depth of small stones in
the openings of PICPs.
Permeable interlocking concrete pavements
Ice and snow can melt into the pavement
Water does not collect on the surface and re-freeze
Permeable interlocking concrete pavements
Sand should not be
used for traction
Deicing salts can
Adequate space for
the ice to expand
within the opengraded base
Minimizing the risk of
heaving.
Pervious Asphalt and Concrete
Angular crushed stone, usually 3/8”, excluding fines that
normally fill voids
Porous
http://www.youtube.com/watch?v=ScsQYHMfabU
Pervious Asphalt and Concrete
Pervious paving may cost 10%
more than conventional asphalt
Doubling as a stormwater
system and eliminating storm
drains, save 12% to 38%
Reduces retention ponds
Land area saved that would be
used for basins
Pervious Asphalt and Concrete
Minor loss of porosity occurs in
all porous materials over the
first four to six years
One test, an inch of loose fine
was applied
Full porosity was easily restore by
a cleaning with a HydroVac
POROUS ASPHALT
Formulated with larger
aggregate and less fine particles
“Open-graded” surface drains and
supports traffic
POROUS ASPHALT
Asphalt version originally
developed for airport
runways
prevents dangerous surface
ponding
Reservoir holds water
until it percolates into soil
POROUS ASPHALT
Almost 40% of the reservoir’s total volume will be waterholding voids
Cool asphalt
Increase pavement
reflectiveness
Albedo
Asphalt can be
lightened
Asphacolor
Colored at plant
PERVIOUS CONCRETE
Porous concrete withstands heavier and more repeated
loads than porous asphalt
Does not soften under heat
Grass Pave
Grass will not survive daily traffic
Grass for parking stays healthy if used not more than
about one day a week, less in dry climates
http://www.youtube.com/watch?v=wx-CNC7f5xY
GRASS PAVERS
Open-cell unit paver in which the cells are filled with soil
and filled with turf or gravel
Comprised of a grid system, which is made of concrete or
synthetic to distribute the weight of traffic
Appropriate for
Foot traffic
Overflow parking
Driveway
Grass Pave
COST COMPARISON
Asphalt: $0.50 to $1 per square foot
Grass/Gravel Pavers: $1.50 to $5.75 per square foot
Porous Concrete: $2.00 to $6.50 per square foot
Interlocking Concrete Paver Blocks: $5.00 to $10.00
per square foot