Think green… What do you think of? Hybrid cars? Wind power? Asphalt?
Wait, what? Did you say asphalt?
While asphalt isn’t the traditional herald of green living, it’s a lot greener than you think.
But… It’s Petroleum-Based!
Asphalt is petroleum-based, but it’s inert, meaning it doesn’t leach into the surrounding environment. A 1997 study conducted by the Marine Science Institute (MSI) (Impact of Runoff from Asphaltic Products on Stream Communities in California) analyzed pollutants in stormwater runoff. While pollutants were found, they were from vehicle emissions, oil drippings, etc., not from the pavement. Further research has also concluded that pollutants in runoff are caused by the vehicles using the pavements, not by the asphalt itself.
OK, it’s great news that the asphalt doesn’t leach out chemicals and heavy metals, but that’s net zero, not positive.
You might be surprised to know that some asphalt actually improves the quality of stormwater runoff. These have open-graded surfaces to allow water to pass into a stone recharge bed below, temporarily storing and filtering it instead of letting it run directly into waterways. This is a lot like the filtration of soil layers and removes pollutants that would otherwise be carried into waterways. In fact, full-depth porous asphalt pavements are encouraged by the EPA as a best management practice for stormwater.
Asphalt can be recycled and reused many times. At least 90 million tons of old asphalt pavement is crushed and recycled into new asphalt annually. Wolf Paving recycles 100% of the asphalt they remove from job sites, plus accepts recyclable material from other contractors, saving these materials from landfills and greatly reducing the natural resources needed to produce all-new asphalt.
So next time you’re driving your hybrid on asphalt paving, remember that it’s much greener than it seems!