April 1, 2005

Professor Gonwa – Pervious Pavement Demonstration Project

• Demonstrate feasibility of stormwater management practice
• High visibility project
• Educational component
• Measure effectiveness
• Complete by end of 2005

Project Site – Upper section of Broadway lot

Water that doesn’t soak into pavement will go into drain tiles (open pavers filled with pea gravel)

Subgrade – clay

Rainwater doesn’t run off – just soaks through – point of pervious asphalt

Layers – concrete

• Pervious concrete
• Open crushed aggregate
• Subgrade

Layers – asphalt

• Pervious asphalt
• Crushed aggregate
• Gravel
• Subgrade

Use Eco-creto (like glue)

Bio-retention swale between lower and upper lots

Project elements

• Design and project management
• Construction (over summer)
• Effectiveness documentation – Where we would help
• Education program
• Maintenance
• Cost Sharing

Advantages

• Pollutant removal
• Less need for curbing and storm sewers
• Improved road safety because of better skid resistance
• Recharge to local aquifers

Disadvantages

• Engineers and contractors lack experience in this technology
• May clog if improperly installed or maintained
• High rate of failure
• Risk of groundwater contamination
• Building codes may not permit
• May become anaerobic if it doesn’t dry out between rain events

Research Needs

• Can it be retained for long period of time
• Can it remove pollutants after subfreeze?
• What is cost of repairs?

Design challenges

• Demolition
• Topography
• Pervious pavement - slopes
• Specs
• Under drainage
• Effectiveness of testing design
• Cost containment

Documentation of Effectiveness

• Monitoring plan – due Apr. 4
• Field day for performance testing – Sept 2005
• Project report

Next meeting:

April 8, 2005

Planned Activities:

River Cleanup, April 23