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10 CHAPTER 1 Introduction and Research Approach Introduction that understanding into all aspects of road development are needed." "For a generation, North Americans have been in simul- taneous pursuit of twin goals that are inherently in conflict. Dr. Lance Gunderson (chair) On the one hand, they seek to harvest the manifold benefits Committee on Ecological Impacts of Road of an expanding road system, including a strong economy, Density, National Research Council more jobs, and better access to schools, friends, family, Preface to Assessing and Managing the Ecological recreation, and cheaper land on which to build ever larger Impacts of Paved Roads181 homes. On the other, they have growing concerns about "My visions for the future are as follows. Road design in threats to the natural environment, including air and water future will commence with selection of routes with least eco- quality, wildlife habitat, loss of species, and expanding logical impacts. Wildlife bridges and tunnels will be located urban encroachment on rural landscapes. . . . Not surpris- and built to minimum standards. There will be ecological ingly, these conflicting demands clash wherever transporta- restoration of roadside verges. tion decisions are made, whether at the federal, state, or "For every square metre of road there will be at least the local levels. . . . ad hoc environmental analysis has left many equivalent of land set aside for nature. Roads will become gaps in our understanding of effective mitigation for linear nature reserves with hedgerows of native species and a individual road projects and is unlikely to ever lead to ef- wide swathe on either side as a nature reserve. These linear fective mitigation of the macro effects of a growing system nature reserves will be habitats for rare and endangered of roads." species. Roadside verges will be enjoyed by all and traffic will Thomas B. Deen, Executive Director (retired) slow to allow travelers to enjoy roadside nature." Transportation Research Board, National Dr. Ian F. Spellerberg, Professor of Nature Conservation Academy of Sciences Lincoln University, Aotearoa, New Zealand Member, National Academy of Engineering Chapter 8 of Ecological Effects of Roads217 Foreword to Road Ecology: Science and Solutions98 These remarks suggest that transportation services and "In the past century, dramatic changes have been made in environmental concerns need to be effectively linked in a the U.S. road system to accommodate an evolving set of landscape context-sensitive planning, construction, and needs, including personal travel, economic development, monitoring process. They also provide an optimistic vision and military transport. As the struggle to accommodate of the future, given the concerted efforts and purposeful ac- larger volumes of traffic continues, the road system is in- tivity towards linking transportation services and ecological creasing in width and, at a slower pace, overall length. As the services that have increased dramatically during the past few road system changes, so does the relationship between roads years. For decades, environmental mitigation was not con- and the environment. With the increase in roads, more sidered an integral part of road construction and piecemeal resources are going toward road construction and manage- and haphazard mitigation approaches did not provide high- ment. More is also understood about the impact of roads on way planners and engineers with useful data that could be the environment. To address these matters, a better under- generalized to different situations. However, following the standing of road ecology and better methods of integrating completion of the interstate highway system, a new post-

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11 interstate era began with the passage of the Intermodal Sur- the actual dimensions of the road (length and width) as well face Transportation Efficiency Act of 1991 (ISTEA), which as the dimensions of associated structures, e.g., the right-of- effectively shifted responsibilities and funding from national way. The virtual footprint is much larger and includes the priorities to local needs and greater state and local govern- area where the indirect effects of roads are manifested. The ment authority, while at the same time placing greater em- roaded landscape has both direct and indirect effects on phasis on environmental mitigation and enhancement.98 In wildlife species, community biodiversity, and ecosystem 1998, the Transportation Equity Act for the 21st Century health and integrity. The most prevalent direct effect is road- (TEA-21) retained this basic emphasis. The 2005 Safe, Ac- kill. Indirect effects include habitat loss, reduced habitat qual- countable, Flexible, Efficient Transportation Equity Act: a ity, fragmentation, barrier effects, and loss of connectivity Legacy for Users (SAFETEA-LU) continued this move to- resulting in restricted or changed animal movement patterns. ward environmental mitigation and gave even greater im- The virtual footprint, therefore, can be understood only when portance to facilitating both terrestrial and aquatic passage put into a landscape context-sensitive perspective. Here the of wildlife, while also instructing that when metropolitan Cinderella Principle needs to be applied, i.e., establishing mit- plans and statewide plans for transportation are developed, igation that effectively "shrinks" the virtual footprint to more they must include "a discussion of potential environmental closely resemble the physical footprint.26 For surface trans- mitigation activities and potential areas to carry out these portation, applying the Cinderella Principle means that high- activities" (SAFETEA-LU, Public Law 109-59, Title VI, way planners and engineers need to continue to incorporate Sec.6001 Transportation Planning Transportation Bill [Con- mitigation measures that restore ecological integrity and servation provisions of interest in SAFETEA-LU found landscape connectivity, while at the same time ensuring safe at Defenders of Wildlife site: www.defenders.org/habitat/ state-of-the-art transportation services in a cost-effective highways/safetea/; to read the text of the bill, see frwebgate. manner. This job is not inherently difficult, but it does re- access.gpo.gov/cgi-bin/getdoc.cgi?dbname=109_cong_public_ quire purposeful activity guided by informed, synthetic laws&docid=f:publ059.109]). analyses that reflect true benefits and costs. The research team In Canada, Transport Canada published Road Safety defined transportation services to mean, among other things, Vision 2010, which calls for decreases of 30% in the num- safe, efficient, reliable roads; inexpensive transportation; ber of motorists killed or seriously injured. Over the last properly constructed intersections: safe and quiet road sur- decade, legislation and policy including the National Parks faces; good visibility; safe bridges; and good signage. By Act and the Parks Canada Policy document have placed the ecosystem services, the research team means clean water, highest priority on the protection of ecological integrity, clean air, uncontaminated soil, natural intact landscape and include mitigation for wildlife on upgrades to high- processes, recreational opportunities, abundant wildlife, nor- ways within National Parks. Additionally, the recent mal noise levels, and a connected landscape that leads to Species at Risk Act in Canada has made planning and mit- restoration and maintenance of life-sustaining ecological igation for WVCs even more critical a concern for highway processes. planners and engineers. Given the mandate of these major Currently across North America, a mismatch exists. Ecosys- legislative acts, highway planners and engineers across the tem services have been compromised by road construction. United States and Canada have begun to integrate mitiga- The virtual road footprint is too large. The research team tion as part of their mandate. For example, British Colum- suggests that the overarching principle that needs to guide fu- bia has developed a 10-year strategic plan to reduce wildlife ture road construction, renovation, and maintenance also collisions by 50%. However, even with forward-looking ac- needs to link both transportation and ecological services. That tions and excellent reports such as Assessing and Managing is partly accomplished by reestablishing multiple connections the Ecological Impacts of Paved Roads181 and a large litera- across the landscape. The mechanism by which connectivity is ture on ecological "road effects," there remains an obvious established involves moving from roaded landscapes that are lack of synthesis documents to inform and help guide high- nearly impermeable to landscapes that are semi-permeable way planners and engineers with environmental mitigation and finally, to landscapes that are fully permeable; when and enhancement. Linking transportation and ecological accomplished, the landscape is connected, and ecological ser- services effectively requires an integrated understanding of vices are restored. Nearly normal hydrologic flow, facilitated the science so that mitigation practices may be based on animal movement, reconnection of isolated populations, and data. gene flow are made possible. In other words, the Cinderella Historically, linking transportation and ecological services Principle of shrinking the virtual footprint has been applied may have seemed inherently in conflict but they need not be effectively, restoring landscape permeability. Ecological so. One can envision roads as having a physical and a virtual objectives have been met coincident with a continually effec- footprint. The physical footprint is easy to see and includes tive roadway network.