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P R E S E N TAT I O N S O N T R A N S P O RTAT I O N S U S TA I N A B I L I T Y I N D I C AT O R S 15 Place intense focus on community engagement in Road location and design that take advantage of all planning efforts to understand equity and social sta- scenic vistas and historic sites and that protect environ- bility impacts; and mentally sensitive areas, and Strengthen transportation and land use partner- Road ecology. ships as a primary strategy for good equity and social stability outcomes. The following are among the challenges facing sus- tainable transportation and development: LAND AND COMMUNITY It is easier to keep doing what you know than to try something new. Elizabeth Deakin Reuse, rehabilitation, renovation, and infill can be costly and may generate opposition. Elizabeth Deakin began her presentation on land use, Infrastructure provision, pricing, and funding development, and sustainable transportation by high- policies sometimes favor new areas. lighting key strategies for sustainable development and Design standards for arterials and highways transportation in urban, suburban, and rural areas. The emphasize vehicle throughput to the detriment of other following are among the key strategies for sustainable street functions. urban and suburban development: Funding for sidewalks or street trees is lacking. It is difficult to meet transportation needs in low- Investment and reinvestment in existing districts density suburbs and rural areas for those without cars. and neighborhoods, including preservation, renovation, There is not enough funding for operations and and reuse of structures; maintenance. Upgrades to infrastructure (sewer, water, streets and highways, telecommunications, parks); Despite these challenges, successes are found all over Upgrades to services (schools, police, fire); the country. The successes, however, are not yet trans- Development of higher-density communities, espe- lating into an overall development trend. Some regions cially near transit; are building on project successes to devise a regional Development of mixed-use real estate, especially strategy, and some state departments of transportation in downtowns and city centers; and are reforming their policies to integrate land use and Infill of urban areas to create contiguous growth. community values. The differences between the success stories and the sto- These urban and suburban development strategies ries of those who have tried and failed were summarized. should be coupled with transportation strategies such as Environmental quality, equity, and economic develop- sidewalk improvements, transit service improvements, ment are fundamental objectives of planning processes, signal timing favoring person trips rather than vehicle not post hoc evaluation criteria. In instances of success, movements, and clean and well-paved streets. planners are not just forecasting but also backcasting to In rural areas, the key strategies for sustainable figure out how to get to a future that people want. development are slightly different and include the fol- lowing: HABITATS AND ECOSYSTEMS Preservation and renewal of main streets and vil- lage centers; Richard Forman Preservation of rural landscapes and views; Conservation of agriculture and open spaces; Richard Forman began his presentation by stating that Cluster development; and the objective of sustainable transportation with regard Economic development and job training to main- to habitats and ecosystems should be to mesh safe and tain, increase, diversify, and improve jobs. efficient mobility with natural processes and biodiver- sity. Society should aim to improve natural systems As with urban and suburban areas, rural sustainable along the road network while reestablishing a connec- development strategies should be coupled with trans- tivity of natural areas and green corridors that the road portation strategies as follows: network has cut into small parcels. The presentation then focused on seven aspects of road ecology: Traffic calming on entering towns, Sidewalks and bike lanes in towns and walking 1. Road kill. This is generally a minor issue excep- trails and bike paths through the countryside, tion when animals that reproduce slowly are affected.

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16 I N T E G R AT I N G S U S TA I N A B I L I T Y I N T O T H E T R A N S P O RTAT I O N P L A N N I N G P R O C E S S 2. Traffic disturbance and wildlife. A study was dis- patterns of wildlife. Overpasses to increase connectivity, cussed that found that low-volume roads do not have any not only for animals but also for farmers and hikers, statistical effect on the breeding or existence of birds sur- should be used. rounding the roadway. As volume on roads increases, 5. Water and aquatic ecosystems. Sedimentation, however, the study showed a significant effect on the road salt, and other pollutant runoff from roads affect breeding and existence of birds. The size of the affected water quality. Such impacts, however, can be mitigated area also increases as traffic volumes increase. Solutions by disconnecting roads from water bodies and by using to the impacts of traffic on wildlife may include improved soil as a filtering substance for runoff. vehicle and pavement designs that reduce noise. 6. Road density. The current road network's insensi- 3. Roadside vegetation. A primary function of road- tivity to ecology was discussed, and an ecosystem- side vegetation is safety. If roadside trees narrow the friendly transportation infrastructure that maintains vision ahead, drivers slow down. Roads in the United large road-free areas and concentrates traffic on a few States, however, are designed for speed, with grassy large roads was described. open areas along the roads. Trees planted up to the side 7. Regional transportation planning. Currently, air of the road could improve safety by reducing speeds and quality is the only environmental impact of transporta- at the same time provide habitat for wildlife. tion that is adequately modeled on a regional basis. Sim- 4. Connectivity of land. The existing road network ilar modeling should be conducted for other major severs the land and affects the habitats and migration environmental issues.