Band-aids and Quick Fixes: Australia's Problems with Road Runoff Management

Roads, highways and freeways are the arteries that keep Australia's lifeblood flowing. Until recently little was known about the environmental impacts of these vital links, aside from the social inconvenience, extensive clearing and soil erosion associated with construction. It has emerged over the last decade that roads, and the vehicles that use them, cause notable fluxes of pollutants to receiving waters due to the runoff. Current results from a School of Environmental Engineering, Griffith University and Main Roads study into road runoff pollutant concentrations are discussed. Results indicate that traffic volume is only a small factor in influencing the concentration of pollutants. Statistical analyses show that site specific features such as intersections and exit lanes have a strong relationship with the concentration of the metals, copper, lead and zinc. Significant funds have been spent installing different stormwater treatment devices and methods around the country to ameliorate these problems. However, their removal efficiency and overall benefit to the environment has not been widely reported. This paper evaluates some of the methods currently used and discusses their results. It investigates the overall effectiveness, costs and benefits, and provides some suggestions on future management.