This presentation shows many locations where pavers were used for decorative purposes and could have been used for stormwater management. Simplified cross sections of permeable paver systems that result in good infiltration and meet industry standards are presented.
Permeable Pavers: Missed Opportunities and Simplified Cross Sections
1.
19th Annual EPA Region 6 Stormwater Conference
September 17-21, 2017
Permeable Pavers: Missed Opportunities
and
Simplified Cross Sections
by
Elizabeth Arceneaux, P.E.
and
David Hasness, P.E.
2. Topics to Cover
Impermeable Pavers vs Permeable Pavers
Importance of limiting impervious cover
Infiltration testing and interpretation
Missed opportunities for infiltration
Simplified cross sections for construction standards
adoption
3. People Love Pavers
Decorative
Unique
Elegant
Cool
Durable
Dell Seton Medical Center
Austin, TX
13. Importance of Permeable
Impervious Cover (IC)
Adds to increased runoff
Poorer water quality
Greater than 10-15% IC leads
to stream degradation,
adverse effects (1)(2)(3)
40 -70 % IC is not uncommon
for urban areas
References
(1)Greater Edwards Aquifer
Alliance, 2014 Low Impact
Development Manual
(2)Schueler, T. 1994, King et.al,
2011
(3)San Marcos Water Quality
Protection Plan for the HCP,
2015
14. Impact of IC
• Utilities are unearthed
• Road is undermined
• Stream bank is Eroded
• $ 3,000,000 creek restoration
project (San Marcos)
Increased flooding?
15. Reference: Greater Edwards Aquifer Alliance,
2014, LID Manual
We put a lot of effort into thinking about IC
Now
lets…
16.
Permeable path @ Texas State University. Large tree protection!
Do SomethingAbout It
17. Step by StepWe Change our Nature
If aesthetics is the driver, why not go permeable too?
Easy testing to verify performance
Make resources available for all to use
Clear construction standards to insure success
Include sections and details in municipal construction
standards so they are easy to find
18. Step by StepWe Change our Nature
If aesthetics is the driver, why not go permeable too?
23. Simplified Cross Sections for
Municipal Construction Standards
References:
Interlocking Concrete Pavement Institute
American Society of Civil Engineers and
Environmental & Water Resources Institute
San Antonio River Authority
Concrete Paver Manufacturers
Project Specific PICP Sections
Make resources available for all to use
33. Benefits of Standardizing
Simplifies designs for PICP in neighborhoods,
casual spaces and plazas
Ensures high infiltration of built surfaces
Reduces uncertainty and increases
confidence
Allows more widespread use of PICP
***PICP CAD files collected by Authors and available in Dropbox
(by clicking this link)
34. Resources
• ASCE/EWRI, Permeable Pavements, 2015, Permeable
Pavements Task Committee
• ICPI, Permeable Interlocking Concrete Pavements, Fourth
Edition, David R. Smith, 2011
• ICPI Specialist Course, 2009 First Edition
• ICPI Tech Spec #18 , 2013, Construction of Permeable
Interlocking Concrete Pavement Systems
• ICPI, Tech Spec #23, 2017, Maintenance Guide for
Permeable Interlocking Concrete Pavements
35. In Summary
Impermeable Pavers vs Permeable Pavers?
Are we missing opportunities to infiltrate?
Do we want to reduce impervious cover?
Can we include PICP cross sections in our
construction standards?
If the answer is yes, then we can increase our use
of this valuable stormwater management practice.
37. To see a 1 ½ minute video of the underdrain
discharge at the Texas State River House
Permeable Paver Parking Lot, following 9 inches
of rain right click this link and select open (takes a
minute to open):
River House Perm Paver Discharge 8-28-17
This was the discharge following several
days of rain from Hurricane Harvey
8/28/17
BONUS MATERIAL
(video, costs and more sections)
38. ICP Design for Heavy Duty Pedestrian Section
What about co$t$ ?
• 8 inch of compacted base is actually 10 -12 inch
before compaction
• Cost of compaction (equipment)
• Cost of density testing, proctors
• About $13/ft2 road base and $5-7/ft2 pavers OR
39. 12 INCH
PICP Design for Heavy Duty Pedestrian
• Open stone 2 inches #8 or 9, and 12 inches #57
• Light compaction equipment
• No proctors, no densities
• About $13/ft2 open base and $5-7/ft2 pavers
40. Parking lot with concrete drive lanes, PICP and open base
below all of it
Gragg Park,
Houston, Texas
41. Preventive Maintenance
Sweeping / Vacuuming Intervals: Regenerative Air
Recommended Minimum 1 - 2x Year
O&M Cost Estimated To Be ≈ $ .02 - .03 / sf
