Photo: Tomwsulcer, CC0, via Wikimedia Commons
Tom Blackburn
Trails through natural areas have undeniable benefits, including improving our mental well-being, providing access for outdoor education programs, and reducing air pollution and greenhouse gas emissions if people use them instead of driving cars. However, the environmental impacts of trails get minimal if any consideration when local, state and federal officials are planning and considering building or modifying trails.
In planning development projects like trails, the first question should be, “What’s there?” The federal National Environmental Policy Act is designed to answer that question and to evaluate environmental impacts, good and bad. That law could be a model for local and state governments for trails and other development projects.
Trails Can Have Adverse Impacts
The environmental harm caused by trails that are not properly designed or managed is not always obvious, but it can be substantial, particularly for paved and lighted trails. Trails through natural areas, including our urban forests and wetlands, can cause irreparable damage to delicate ecosystems. Construction often involves cutting down mature trees. Construction equipment damages the root systems of trees in the construction area and compacts soil, which can permanently alter the hydrology, the plant communities, and the wildlife that depends on them.
Trails also serve as a vector for the introduction of invasive species, further damaging habitat and resulting in loss of more native species. Lighted trails attract some wildlife to the lights, where they are preyed upon; they repel other wildlife, reducing the size of their habitat; and they disturb the daily rhythms of animals, resulting in loss of sleep, additional stress, and harm to their reproductive cycles.
Trails often fragment forests and other habitats. Many species need large, intact expanses of habitat. Edge habitats are “invitations” to invasive species and predators. Trail users through forests can mean more disturbance, noise and trash.
More pavement can mean more polluted runoff. A Clifton Institute Study found that if more than 30 percent of an area within 250 meters of the spotted salamander’s breeding pool is impervious, these salamanders are less likely to breed.
The lack of adequate evaluation of the environmental impact of trails through parks and natural areas before an alignment is selected has resulted in proposals to construct trails throughout northern Virginia that would cause significant environmental damage. Sometimes natural resource advocates have been able to deter construction. For instance, advocates succeeded in having Fairfax County remove from its plans a proposed bike trail through wetlands at Huntley Meadows Park that would have harmed critically important habitats and ecosystems. Some proposed trails in Arlington County would have damaged rare ecosystems. Other potentially damaging trails are still in the planning stages. A proposed segment of the Cinder Bed Road Bikeway in Fairfax County could harm rare habitat, and lights on the trail would disturb area wildlife. W&OD Trail expansions in Arlington County, still on the drawing board, threaten to destroy more habitat and potentially add lighting that can harm wildlife. Proposed trails through the remaining urban forest in Fairfax City would result in clearing 1,200 trees and cause other harm to the forest. Widening the paved trail that goes through the Dyke Marsh Wildlife Preserve could disrupt habitat, impair water quality, damage root systems, disturb nesting birds and migrating fish, and harm trees and other vegetation. ASNV has opposed each of these proposed paths as well as others whose environmental impact was not adequately evaluated.
Trails Need Stronger Environmental Requirements
A recent article in the Virginia Mercury, an independent nonprofit online news organization covering state government and policy, highlighted the need for more effective environmental oversight of recreational trails. The article, by Wally Smith, an Associate Professor of Biology at the University of Virginia’s College at Wise, pointed out that trails are often assumed to be exempt from environmental laws, and that Virginia has no requirements on how trails should be designed and managed to benefit the environment.
Virginia law and Federal regulations require environmental review of proposed bike paths that may cause significant environmental harm. The Virginia Administrative Code, 9VAC25-830-140, provides that development in Resource Protection Areas is exempt from environmental review only if it does not affect water quality, and it gives local governments authority to review exemptions from environmental review. However, the Virginia Department of Transportation appears to give bike trails a categorical exclusion from environmental oversight, even in the face of local opposition. VDOT’s policy is inconsistent with the National Environmental Policy Act and the Federal Highway Administration regulations on which VDOT apparently bases its policy. The FHWA’s regulations provide that actions that normally would qualify for exemption from environmental review but that would cause significant environmental impacts or result in substantial controversy on environmental grounds must be subjected to environmental review.
Virginia’s Wildlife Action Plan lists 883 species that are critically imperiled or in decline. “Habitat loss is the single greatest challenge impacting these species,” the plan states. More trails and fragmentation of habitat could mean more habitat loss.
ASNV will continue to weigh the benefits and environmental harms of proposed trails through natural areas, and we will oppose them if we conclude that the harms outweigh the benefits, or that redesign of the paths will reduce environmental harm. If you are aware of a proposed trail that would harm the environment, let us know.