Some Recent Environmental Pavement Technologies – Fact or Fiction

The roadbuilding industry has been working towards environmental stewardship in many aspects of pavement construction. As an example, almost 100% of reclaimed asphalt pavement is recycled and used in pavement construction. In fact the amount of recycled asphalt pavement used exceeds that of glass, paper, aluminum and plastic combined. Warm mix asphalt represents another advancement with significant environmental advantages, such as reduced fossil fuel costs and less emissions. More recently, two pavement technologies have come to the forefront; permeable pavements and solar pavements.

Permeable pavements offer an enhanced method for managing stormwater. These pavements, generally used for parking lots or other low traffic applications, allow stormwater to drain through the pavement surface into a stone recharge bed (or reservoir) and infiltrate into the soils below the pavement. The surface of a permeable pavement can be specially designed asphalt concrete or Portland cement concrete, or permeable pavers. Advantages include purifying stormwater runoff, and replenishing water tables and aquifers rather than forcing rainfall into storm sewers.

Solar pavements are even a more recent environmental development. Solar pavements (or surfacing) is a modular system of specially engineered solar panels that can be walked and driven upon. In some cases the panels contain LED lights to create lines and signage without paint. They can contain heating elements to prevent snow and ice accumulation. The Netherlands built the first solar road, a bike path, in 2014. France announced a bolder move recently that over the next five years, it plans to install 1,000 kilometres of solar roads. Installations in North America are likely “just around the corner”. 

This paper will have the objective of providing a fair, but critical review of these two pavement technologies, specific to the Canadian context. There can be no denying that these innovations have a significant environmental upside; but does that upside come at a cost, a cost that may or may not make good sense?