Permeable pavement allows rainwater to filter into the ground while providing a durable surface for vehicles to drive on. While gravel driveways and other pourous materials are a common form of this, other types composed of interlocking concrete blocks or plastic cell networks can allow vegetation to poke through.
Permeable systems can cost more to lay than asphalt or poured concrete and, depending on the material, may require more maintenance. But the results are more aesthetically pleasing, more environmentally responsible, and may save money in the long run.
By allowing rainwater to soak into the ground, permeable systems slow run-off and flooding the sewer systems. Allowing grass and plants to grow improves air quality and reduces the heat island effect.
Permeable paving works best in low traffic areas, like alleys, parking lots, or bus stops, and in some cases may have the additional bonus of calming traffic.
So why wait for an old railroad to be decommissioned before turning it into a greenway? Via Beyond Brilliance, Beyond Stupidity I found this post about permeable paving along the new tram line in Barcelona. The photos show what a lovely difference it makes.
The organization City Farmer worked with the government of Vancouver on three trial installations in their County Lanes project. Read more about the budget and process at the City of Vancouver Web site:
“After evaluating the three designs for their durability and performance, a standard Country Lanes design will be developed. Vancouver is also planning to develop a ‘Sustainable Street’ that incorporates many of the features of the Country Lanes.”