Monday, August 24, 2009

Permeable Pavement. The Real Green Solution To Water Pollution

Permeable pavement is a pavement system which permits water to pass through the surface and into the ground thus allowing the natural filtration process that occurs as water passes through soil and into surface water and local aquifers. Allowing water to pass directly through the surface will facilitate the natural filtering process of water as it passes through the soil and gravel much like filtering drinking water. The added benefit of these systems is that they can save developers and municipalities money by reducing the costly expense related to the building of gutter storm drainage systems and curbs. The costs are competitive with current building materials especially when figuring in the reduction of expenditure on drainage systems.

Typical roadways, sidewalks, driveways, parking lots and roofs are made with impermeable surfaces creating massive runoff of water that also contains pollutants which drain into local creeks, streams and rivers where it adds to the contamination of these systems. The permeable systems can significantly reduce the runoff containing fertilizer, pesticides, oils, detergents and particulate matter from air pollution.

Currently, there are multiple types of permeable pavement systems available which include bituminous pavement or porous asphalt, porous concrete, plastic grid systems and block pavers. Each having a particular functional use depending upon location with costs in the range of $.50 to $4.00 per square foot.

Permeable pavement also tends to be less reflective, causing less glare and allowing motorists to see pavement markings better. These processes are relatively new but have been shown to have nearly the same lifespan as solid impervious materials. This would thus keep maintenance and repair costs comparable to existing materials. Perhaps it is time to utilize more of these materials in the process of creating more green jobs in the new green economy.

Green stormwater and porous pavement
Permeable Pavement


Keith said...

Wouldn't such permeable pavements be problematic, though, for colder climates areas experiencing the extended freezing-thawing cycle every year? If you have water seeping into the pores of the permeable material, then freezing and expanding... sounds like a recipe for more potholes...

Tricia said...

Very interesting article. I'm going to research this a bit more. Thanks.

TC said...

Hey Keith. Actually in the studies they have found that these materials actually performed well with the freeze/thaw cycle. In addition, the initial targets for this type of pavement would not be on what is considered "high" traffic areas.

TC said...

@Tricia. Yea, look into it. Innovative stuff is happening all around us. We need to work toward implementing it more aggressively.