Evaluating phosphorous from vehicular emissions as a potential source of contamination to ground and surface water

It is well documented that urban runoff and roadside soils can become contaminated with particulate deposits, especially heavy metals, sourced from vehicles. However, phosphorous from vehicular sources has been given little consideration as a possible roadside contaminant. This paper examines the potential contamination of surface water (via runoff to storm drains and discharge to waterbodies) and groundwater (via roadside soil infiltration) by the phosphorous deposited onto pavement and road shoulders in the city of Waterloo, Ontario, Canada. Total and soluble reactive phosphorous concentrations in roadside soil and runoff samples were determined for two study sites. Subsequently, the results were statistically analyzed. Following comparison to other sources of urban runoff, it was concluded that roadways are a significant source of phosphorous in urban runoff, with high potential to impact surface water. Conversely, results of this work indicate that vehicular-sourced phosphorous does not pose a significant threat to groundwater.