When access proliferates excessively, highways lose their intended function and capacity. Arterial roads, designed to connect communities, instead become congested with local traffic, leading to delays and safety problems, not only for motorized traffic but also for pedestrians and other nonmotorized traffic. Until recently, degradation of service has typically occurred in about thirty to forty years, but the pace appears to be accelerating.
The loss of capacity comes at high cost, both financial and aesthetic. Users experience delays, inconvenience, and increased vehicle operating costs. To compensate for lost capacity, government agencies add lanes, often consuming adjacent property. Costs of construction and right-of-way acquisition can be substantial. When capacity deteriorates excessively, or when no room exists for additional lanes, parallel routes must be constructed, further dissecting community neighborhoods, and at even greater cost.
Ironically, lax access policy also harms the very interests that press for it to begin with. As an arterial highway loses its capacity, traffic volume declines, causing loss of business along the route. Faced with declining volume, businesses relocate along another route, where the cycle begins anew.
Several barriers stand in the way of a sound and coherent highway access policy. StakeholdersCsuch as local officials, developers and business ownersCsometimes lack information about the long-term effects of lax access policy and, conversely, the benefits of sound policy. Those who understand the value of consistent policy lack ways to quantify and effectively communicate the costs and benefits to others. Finally, necessary partnerships, not only between state and local agencies, but also with business and political interests, may not be sufficiently cultivated.
Research is needed to develop a policy, procedures and design guidelines for controlling highway access in rural states of the upper great plains and the mountain west, and to evaluate and document the value of sound and coherent access policy. Furthermore, the research should produce materials that can effectively communicate with groups affected by highway access decisions, and help foster partnerships between those groups.