Two recent laws are having major impacts on transportation planning and travel forecasting. Both the Clean Air Act amendments and the 1991 Intermodal Surface Transportation Efficiency Act (ISTEA) emphasize the role transportation systems play in attaining federally mandated air quality standards. These two pieces of federal legislation are among the most important landmarks in a decade-long shift of emphasis in regional transportation planning. The acts require new, detailed, accurate analyses of the potential impacts of transportation improvements on congestion, travel, and land use. What is more important, the strategies developed to help meet regional air quality standards will affect public investments in the transportation network and public transit, which in turn will affect future regional development.
The Clean Air Act was enacted to protect and enhance the quality of the nation's air resources, to prevent and control air pollution, and to provide technical and financial assistance to state and local governments to develop pollution control programs. Congress recognized that the growth and complexity of air pollution due to urbanization, industrial development, and the increasing use of motor vehicles posed a danger to public health and welfare. The act sets national air quality standards and requires states to curb pollution from stationary and transportation-related sources. The 1990 amendments significantly expand the transportation planning requirements previously contained in the 1977 Clean Air Act. ISTEA is intended to develop an economically efficient and environmentally sound national intermodal transportation system. It gives state and local governments greater flexibility in addressing transportation issues and provides funding for transportation programs that contribute to meeting air quality standards.
Recent litigation in the San Francisco Bay Area pointed up many deficiencies in the current state of travel modeling and analysis, particularly in assessing air quality impacts from transportation projects. Environmental groups challenged the adequacy of transportation planning in the Bay Area even though the Metropolitan Transportation Commission (MTC), the regional transportation planning agency, was at the time a national leader in transportation planning methods. The lawsuit nevertheless contended that planners had failed to consider the potential land use implications of new freeway construction and funding decisions, failed to implement transportation control measures included in the regional transportation plan designed to reduce traffic and achieve cleaner air, and failed to meet other federal requirements of the 1977 Clean Air Act linked to the urban transportation planning process.
Besides challenging the planning process as inadequate, the plaintiffs also contended its content was flawed—that the standard models being used were inappropriate to the task assigned them—and therefore the result could not be relied on for accurate assessments of the air pollution impacts from freeway construction. The federal court ruled in favor of the plaintiffs based on the defendants' own planning commitments, and after a couple of years of legal wrangling over how the defendants would comply with the court's order, the parties reached a settlement in which the regional transportation planners agreed to modify their procedures to better address air quality concerns.
The Bay Area case, which is the subject of this book, is frequently cited as a threat to the current standard approach to regional transportation planning, because it holds planners to a heightened standard in meeting national air pollution goals. Although the case arose before the new legislation took effect, the court did address the impact of the 1990 Clean Air Act Amendments, particularly on existing pollution control strategies. Even prior to the amendments, the 1977 Clean Air Act required regional planners to incorporate air quality goals into their transportation planning process to receive federal highway project funding. The court ruled that the 1990 amendments reinforced those requirements and did not permit the agencies to relax their pollution control efforts. In brief, the decision held that existing planning methods failed to satisfy the 1977 act and by extension would also not be adequate to comply with the 1990 amendments.
The decision has major implications for future planning practice under the 1990 amendments and ISTEA because the court held the defendant transportation planning agencies responsible for greater proficiency in predicting regional impacts from freeway construction and upgrading than most current modeling practice allows. This higher level of analysis has become mandatory for all states under the new legislation and the EPA regulations designed to implement it. The lessons drawn from the Bay Area litigation should serve as a guide to other jurisdictions that do not presently comply with the federal clean air standards. Unless better techniques can be devised to assess potential air quality impacts of new freeways and added traffic, we may expect increasing challenges in court to slow or halt new highway and mass transit projects.
The case also raised a number of important questions concerning the relationship between transportation system investment and regional growth. Plaintiffs argued that when new highways are planned to respond to forecasts of future land development, their eventual construction will itself change those land use patterns and that this feedback loop must be incorporated into the modeling process. Although the court ruled that it has never been shown that highway construction causes growth in a region that would not otherwise have occurred, it did hold that highway construction may indeed affect the distribution of economic development and residential population within a region. Regional planners in the Bay Area were required to consider these form-inducing effects of highway construction, a practice that may well be required elsewhere under the new acts.
The basis for the plaintiffs' lawsuit was that the various defendants all had some degree of responsibility for developing, approving, and implementing the SIP [State Improvement Plan] for the Bay Area but had failed to achieve the reductions in air pollution called for in that plan and had failed to carry out specific portions of the plan designed to improve air quality. Plaintiffs argued that the court should require the planning agencies to implement all the components of their regional air quality plan. The defendants argued that the plan's provisions were advisory and should be treated with flexibility and should not be literally or rigidly interpreted. The district court, although flexible and interpretive in some ways, held that the plan constituted a set of relatively firm commitments that the state and local defendants would have to follow.
Specifically, the court ruled that the defendants had to implement all the control measures listed in the SIP and also had to identify and adopt additional contingency measures when it became clear that the Bay Area would not achieve the federal air quality standards. In addition, the court decided that the MTC [Metropolitan Transportation Commission]'s methods for ensuring that highway projects in its regional transportation plans and programs conformed to the SIP were insufficient and ordered the MTC to delay work on some existing projects and postpone decisions on any significant new projects until adequate procedures were developed. These rulings have already caused planners all over the country to be much more circumspect about the provisions they include in their transportation plans. Before turning to the specific legal issues raised in the case, it will be useful to review the background leading up to the adoption of the air quality plan that was under attack and to describe some of its key elements.
Given the national interest sparked by this decision, what, on a practical level, can be said to be its impact? By holding that the plaintiffs could not enforce specific contingency provisions and conformity procedures, it certainly lends support to efforts by environmentalists and federal regulators to force states to clean up their air. An opinion by a federal district judge, though, has limited value as a precedent value. Although it is binding between the parties to the case, and it can have some persuasive force in other similar litigation, other state and federal courts are not bound to follow it. It can, however, affect the direction of federal regulatory policy. For the EPA, it confirmed that SIP commitments are enforceable, which will add some leverage to their rule making and oversight responsibilities. Perhaps buoyed by the success in the Bay Area lawsuit, shortly after passage of the 1990 Clean Air Act Amendments, several national environmental organizations notified a number of metropolitan planning organizations and most state governments demanding a larger role in the planning process and warned them to comply with the new transportation requirements or face lawsuits. More immediately, the decision certainly did have a dramatic impact on transportation planning in the Bay Area, as the following chapters illustrate. It forced planners in various state and regional agencies to seriously consider the relationship between transportation and air quality. It also pushed them to develop new analytical techniques.