Permeable driveway and walkways at Archetype Sustainable House
Permeable pavers at the Green Parking Lot during winter
Pervious concrete, permeable interlocking concrete pavers in the Green Parking Lot
Permeable interlocking concrete pavers at the entrance to the Earth Rangers Centre
Permeable interlocking concrete pavers being installed
Permeable interlocking recycled rubber pavers being installed at the Green Parking Lot
While permeable pavements look like ordinary pavement, they provide environmental benefits by soaking up and cleaning the rainwater and snowmelt (i.e. stormwater) that runs off them rather than draining it directly to storm sewers. This reduces the negative impacts paved areas have (e.g. water pollution and accelerated erosion) on the rivers, lakes and wetlands that receive their drainage and helps restore the natural water cycle.
When properly installed and maintained they can last for 20 years or more. Maintenance involves vacuuming them annually to prevent pre-mature clogging, plowing and applying de-icers only when needed during winter months. Because they drain very quickly, they are less prone to ice build-up during winter thaw-freeze cycles. Sand should not be spread on them during winter as it will clog the joints or pore spaces.
There are four general types of permeable pavements: permeable interlocking pavers; permeable interlocking grids, pervious concrete and porous asphalt. They are all just as strong as ordinary pavement. They can be used on low to medium-traffic roads, parking areas, plazas, walkways and driveways.
The Sustainable Technologies Evaluation Program (STEP) has evaluated the effectiveness of several permeable pavement installations around the Greater Toronto Area and published guidance on their design, inspection and maintenance.
