For decades, Atlanta has been one of the nation’s fastest-growing metropolitan areas, and the Atlanta region is projected to have 4.8 million residents by 2025. Atlanta is a comparatively low-density urban area with only one-third the density of the densest urbanized area in the nation. More than 97 percent of travel in the Atlanta region is by personal vehicles, and in the last decade traffic volumes have risen 3.7 times faster than the rate of roadway expansion. Traffic congestion has become severe and the region is out of attainment with federal air-quality standards, causing the federal government to refuse to release transportation funding.
The Atlanta Regional Commission’s new Regional Transportation Plan (RTP), the transportation blueprint for the next 25 years, seeks to increase residential and employment densities under the mistaken assumption that this will encourage higher transit and less automobile use, and therefore less traffic congestion and air pollution. These assumptions are based on the current fad in urban planning known as “smart growth” that is being pushed by many different advocacy organizations and urban and transportation planners. The problem is that the policy of increasing densities will have the opposite effect of what the ARC and “smart growth” planners believe. Such a policy is more likely to increase traffic congestion and air pollution. That seems to be common sense to most people except for these groups.
Smart growth policies can only be effective if they cause a significant shift of travel from automobiles to transit and walking. The modern metropolitan area is far too complex and interdependent to expect such major travel changes. Regardless of the density, employment (and shopping) for all but a few of the residents of the Atlanta region requires automobile travel. Moreover, the segmented nature of modern trips that combine, for example, travel to employment with shopping or child care make alternatives such as mass transit impractical for most trips. In modern America, increasing residential and commercial densities is largely incompatible with reducing traffic congestion. In our affluent society, densification will simply not produce enough transit use and walking to counteract the higher automobile demand that occurs from having more people and more cars in a particular area. In fact, data from numerous studies show that traffic congestion is worse where population densities are higher. As urban area densities increase, so do vehicle miles per square mile. This does not mean that low-density urban areas necessarily have less traffic congestion. However, it does mean that when new roadway capacity lags far behind population growth and travel demand, as is the case in Atlanta, then traffic congestion would be even worse if the Atlanta region were more compact.
Even if MARTA ridership projections are achieved as set out in the RTP, mass transit will still only carry 3.44 percent of all trips made in Atlanta in 2025, compared to the present 2.56 percent. This means that 97 percent of people will continue to use their automobiles for trips, regardless of whether they live in areas with one or two houses per acre, or areas whose density has been greatly increased. This has already been amply demonstrated by the intense traffic congestion in Buckhead that has resulted from the significant residential and office construction or densification that has occurred in the area since the 1980s, despite the fact that Buckhead is well served by the MARTA rail system.
Obviously, where there are higher urban densities and therefore higher densities of automobile travel, air pollution is more severe. Urbanized areas rated “extreme” with respect to air pollution had an average population density of double or more than that of urbanized areas with no air quality problems.
The point of all this is, of course, that the pressure being felt by local officials to increase urban densities will make traffic congestion worse and cause even greater air pollution problems. Smart growth is not very smart and is based on assumptions that have not been borne out anywhere in the country. A plan that spends the majority of our transportation dollars on mass transit and smart growth strategies is a waste of money that will make our traffic congestion and air pollution problems worse, not better.
Hans A. von Spakovsky was a member of the Board of Advisors of the Georgia Public Policy Foundation. This commentary is based on the transportation study just released by the Foundation and authored by Wendell Cox, a national transportation expert.
The Georgia Public Policy Foundation is a nonpartisan, member-supported research and education organization based in Atlanta, Georgia, that promotes free markets, limited government and individual responsibility. Nothing written here is to be construed as necessarily reflecting the views of the Georgia Public Policy Foundation or as an attempt to aid or hinder the passage of any bill before the U.S. Congress or the Georgia Legislature.
© Georgia Public Policy Foundation (September 6, 2000). Permission is hereby given to reprint this article, with appropriate credit given.