They point out that habitat fragmentation and disruption from highway construction can impact the size of particular wildlife populations, with a secondary effect being an ecosystem of less biodiversity and thus lower value. The researchers also raise concerns about how transportation corridors are used by wildlife and whether plantings, medians, and shoulders have beneficial or adverse impacts on wildlife. They question the noise impacts on sensitive species and how to implement collision avoidance measures. The scientists also say additional research is needed on the impact of transportation projects on the accumulation of contaminants in community and ecosystem food chains. Road sand is a physical stressor but chemical runoff has an impact too.
Road runoff includes polycyclic aromatic hydrocarbons, nitrogen-containing organics and some metals.
The researchers point out that there are presently no widely accepted criteria for evaluating the significance of roadside soil, air and vegetation contamination. Other concerns include impacts from stormwater management and whether mitigation solves or creates erosion problems for streams. Perhaps money should be spent on research so we better understand the impacts of highways before constructing more new ones. A decentralized effort has sprung up to prepare to fight the highway. People are networking and sharing information across the state and the whole northern forest region.