Permeable pavement: an economical, safe, and environmental choice
Cities were paved to provide smooth, durable surfaces for drivers, pedestrians, and cyclists. But impervious pavement also worsens flooding and pollution problems associated with urban runoff.
Enter permeable pavement: a way to keep the functionality of hard surfaces for low-speed traffic â€“ surfaces like driveways, sidewalks, parking lots or alleyways - while allowing water to soak into the ground. Permeable pavement comes in several forms, including interlocking concrete pavers, grass pavers, permeable asphalt and permeable concrete. .
The performance of permeable paving is impressive. A multi-year study of three different types of permeable paving, by the Sustainable Technologies Evaluation Program (STEP), found reductions of 43% in runoff volume and 91% in peak flows compared to a conventional asphalt parking lot. Permeable paving also filtered out pollutants, including nutrients, heavy metals, suspended solids, and oil and grease.
Concerns are sometimes raised about the ability of permeable paving to perform in Canadaâ€™s cold climate. However, the studies at STEP and at the University of Calgary have shown no major issues with winter performance of the technology.
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Brooklyn bets on green infrastructure. The New York City waterfront will be transformed into a 14 mile Greenway, to be used for recreation and to protect the city from future storms like Hurricane Sandy. GI components include rain gardens, wetlands, and porous paving. The Greenway will be an important tool in "mitigating the effects of climate change, addressing imminent stormwater challenges and contributing to overall community resilience" according to the project report.NYC has secured $133 million in funding to complete this project and others, a total of 41 miles of greenway, and has plans for over 200 miles in total.
Flood prevention over cleanup. Disaster relief payments to provinces by the federal government have skyrocketed over the last twenty years due to the increase in extreme weather events. The Federal government is now reducing disaster relief payments to provinces, instead investing $200 million to pay for flood prevention strategies.
Six Ontario communities get the green treatment. In charrettes across the province, design teams got together to envision how sites in the cities of Vaughn, London, Toronto, Oshawa, Mississauga and Brampton could be transformed through the inclusion of green infrastructure. These plans proved to be not only sustainable but economical - cost benefit calculations showed many of the projects would pay for themselves over time.
Testing the waters. The Sustainable Technologies Evaluation Program biannual newsletter recently came out, highlighting exciting new research testing the performance of bioretention, permeable paving, and more. Sign up to receive the newsletter at the STEP website!
Stormwater role model. Deb Martin-Downs, formerly of Toronto Region Conservation Authority and now Credit Valley Conservation, has worked tirelessly to advance the cause of green infrastructure in Ontario. In this profile for the Women in Science series of Canadian Science Publishing, she gives advice for other women considering entering the field.
CVC Case studies share lessons learned in LID construction.The new case studies aim to help contractors, designers, consulting engineers, municipalities, landowners, and inspectors through the various stages of constructing a low impact development project.
Resilience to extreme weather requires grey and green solutions.A Royal Society report recommends a 'hybrid' approach in which governments increase resilience through engineering and ecosystem-based solutions, as well as social and behaviour change.
Living architecture and sustainable energy. 3 February, 2015. Toronto. Learn about innovative approaches for integrating green (vegetated) roofs and walls with other building services to enhance performance, improve indoor environmental quality, and reduce or eliminate energy inputs from unsustainable sources.
FCM Sustainable Communities Conference. 10-12 February, 2015. London, Ontario.The SCC brings sustainability leaders together from across the country to share their challenges and successes, learn from each other, and collaborate to build their own momentum on the path to sustainability.
Water: a risky business. 13 February, 2015. London, Ontario. Credit Valley Conservation and partners invite you to join leaders from across North America and learn about tools to help your small, medium or large municipality manage risk and optimize your investment in water infrastructure.