One of the fundamental goals of the Eastern Corridor Multi-modal Transportation Study is to implement transportation improvements that are consistent with larger regional environmental goals. Of the larger regional environmental goals, the improvement of the region’s air quality is perhaps one of the most important.

In 1990, Congress adopted the Clean Air Act Amendments (CAAA) to address the country’s major air pollution problems. The CAAA regulates six major pollutants: sulfur dioxide, nitrogen dioxide, lead, carbon monoxide, particulate matter and ozone. The Greater Cincinnati region meets the national air quality standards for all of the six major pollutants except for ozone.

Ozone is formed when sunlight reacts with volatile organic compounds (VOCs), principally hydrocarbons, and nitrogen oxides (NOx). VOCs and NOx occur from incomplete combustion of fossil fuels. Transportation sources (motor vehicles) are a major contributor of these pollutants. In 2000, transportation sources accounted for half of the total regional emissions of VOCs and almost a third of NOx emissions. Industrial sources account for nearly one-third of all VOC emissions and almost two-thirds of NOx emissions. Other sources include individually insignificant sources that when added together have a significant impact, like lawn mowers, oil-based paints, boats and dry cleaners.

The Transportation Efficiency Act for the Twenty-First Century (TEA-21) strengthened the Clean Air Act’s ability to meet its objectives and to ensure that improvements in air quality will not be reversed by growth in travel. This Act gives state and local officials tools for adapting the transportation system to meet the CAAA requirements, including increased funding, flexibility to mix project types (e.g., transit, bicycle), and metropolitan and statewide planning requirements. The OKI regional transportation plan defines local commitments to promote alternatives to automobile travel and to enhance mobility while minimizing new highway construction. Air quality is a key criterion for OKI in making decisions for transportation plans, programs and projects.

Transportation source pollution has been significantly reduced through federal legislation requiring vehicles to meet stricter emissions standards and rules implemented in the OKI region by both the State of Ohio and the Commonwealth of Kentucky for inspection and maintenance programs, vapor recovery systems at the fuel pumps and cleaner fuels. These technology-based actions have resulted in lower emission rates per motor vehicle and will continue to be the primary contributor to lower total vehicle emissions.

Transportation conformity is a mechanism to ensure that federal funding and approval are given to those transportation activities that are consistent with the regional air quality goals. OKI has the responsibility to determine transportation conformity for both its four-year Transportation Improvement Program and its Long Range Transportation Plan.

Through its Long Range Transportation Plan, OKI has prioritized and recommended behavior?based strategies to reduce vehicle miles traveled. Travel demand management (TDM) strategies encourage using alternatives to single-occupant vehicle travel, shifting trips out of peak travel periods, or even eliminating some trips altogether. The TDM strategies identified in OKI’s Plan include increased telecommuting and flexible work schedules through employers, expanded rideshare programs, additional opportunities for safe bicycle and pedestrian travel, growth management, consideration of high-occupancy vehicle lanes as an alternative to highway expansion, and parking management. OKI’s Plan also identifies improved transit as a critical component in improving air quality. Expanded bus service, development of light rail and commuter rail, and improved access to the transit system through park-and-ride lots and transit centers would encourage additional transit ridership thereby reducing vehicle miles traveled. The regional plan also identifies measures aimed at easing congestion through improved traffic flow. Measures such as traffic signal coordination, traveler information systems and incident management programs generally have a positive impact on emissions because of decreases in stop-and-go travel and reduced delay due to accidents or construction.

The Eastern Corridor MIS study recommended a multi-modal plan (including bus, rail, highway, bicycle and pedestrian travel improvements) consistent with OKI’s regional air quality goals. This recommended plan was adopted as part of the current OKI regional long range plan. The recommended plan is predicted to reduce vehicular travel in the region by 370,000 miles each day in the year 2020. The follow-up Eastern Corridor PE/EIS study is refining and developing the recommended transportation plan to ensure that these air quality benefits can be achieved or even bettered.