Environmental Impact of Road Surfaces and Innovative Paving Solutions

Road Surfaces and Global Environmental Change

The negative effects of road surfaces on local, regional, and national ecosystems are empirically evidenced and represent a large contributing factor to the increasingly large carbon footprint of developed nations (Switalski et al., 2004). The use of primarily asphalt and tar-based paving techniques, though providing an effective road surface, is damaging not only in the retention of solar radiation — which raises the internal temperature of the earth — but also in the associated chemical runoff and the necessary disruption of existing vegetation and animal life (Forman, 1999). The impact of human manufacturing and agricultural enterprise on the climate is seemingly an inevitability of civilization. However, there are areas of waste that can be limited or repurposed, initially at some expense but ultimately beneficial in the long term — not only for individual nations, but also for the global environment (Switalski et al., 2004).

Road surfaces are composed primarily of tar and asphalt-based pavement. This static substance leaches harmful toxins such as heavy metals and polycyclic aromatic hydrocarbons into the soil and groundwater — not only as a result of asphalt's inherent chemical makeup, but also as a result of its interaction with vehicles and their associated waste (Kosson et al., 2002). Furthermore, when road surfaces must be replaced approximately once every ten years, large quantities of road material must either be reused or disposed of, spreading the effects of such toxins beyond roadways and surrounding areas into landfills and playgrounds, where they may potentially come into direct contact with community water tables or even children and family pets.

Using alternative paving materials, while still utilizing the highly inorganic and ecologically disruptive method of "paving," is counterproductive in that the inherent problems with road surfaces stem as much from their construction as from their chemical composition (Reid, 2000). There is enough paved roadway in the United States alone to drive to the moon and back. This incomprehensibly large space serves no purpose other than the conveyance of human beings and goods from one point to another (Reid, 2000). While transportation is vital to the continuation of human progress, the method by which that transportation is achieved is constrained only by efficacy and imagination.

Currently, technologies are in development that will allow for the collection of heat energy from paved roads — not only for the purposes of contributing to the national grid through thermoelectric generation, but also for preventing ice from forming within road beds during winter (Switalski et al., 2004). Additionally, piezoelectric devices can convert the pressure of cars driving over the road surface directly into electricity. There is also a great deal of research into the use of alternate materials that can minimize the negative effects of chemical leaching and ecological disruption (Forman & Deblinger, 2000).

This research, conducted independently, may aid in the attainment of energy efficiency and environmental protection goals. However, each of these projects is being conducted independently of the others. What this study proposes is a combination of existing and yet-to-be-developed road surface technologies and construction techniques that would capitalize on the inherent energy transfer between cars and the road surface, as well as between the sun and the road surface. This, in combination with a more effective and dynamic containment matrix, may ultimately have not only a long-term positive impact on the environment but also on the immediate ecological systems surrounding the road surface. The proposal is to test heat-sensor receptor panels utilizing both solar and pressure energy in combination with a reclaimed rubber pellet bed set within a natural vegetation matrix.