by James A. Bacon
Thanks to tax increases enacted in 2102, Virginia has roughly $800 million more to spend each year on transportation projects. But that money won’t stretch very far if we use it all to build more lane-miles of roads and highways. An alternative approach is to invest in making our existing assets operate more efficiently. “The Innovative DOT,” a handbook for stretching public transportation dollars in an era of government austerity, provides a half dozen strategies for doing so.
The Virginia Department of Transportation is pursuing some of these ideas, especially the use of technology to eke extra capacity from overloaded interstates, but the state’s newly appointed Secretary of Transportation, Aubrey Layne, would be well advised to review them all to see which might be pursued more aggressively. Key ideas from the chapter, “Transportation System Efficiency,” include:
Reform Level of Service. A rigid focus on Level of Service (LoS), a measure of roadway congestion, can lead to overbuilding. Transportation departments typically base their LoS rating on the period of peak travel delay, which may be bad for only one or two hours per day, or on specific roadway segments not typical of the entire corridor. DoTs should consider payback — how much congestion relief is achieved per dollar spent? Also, they should broaden their focus beyond vehicle capacity, to include walking, biking and mass transit. Finally, they need to consider context. Some places are congested for a reason — they are centers of economic activity. Increasing the volume and speed of traffic sometimes can make those places less desirable.
Context Sensitive Solutions. DoTs often design projects to the highest specifications in the highway design manual, which can make them unnecessarily expensive to build and maintain. Worse, over-engineered roads can lead to increased volume and speed of traffic where it is totally inappropriate, such as commercial districts that need a pedestrian-friendly infrastructure to prosper. It would be helpful here to make Chuck Marohn’s distinction between streets (designed for local access by cars, pedestrians, buses and bikes) and roads (designed for high-speed travel between distant points). Often DoT “improvements” create what he calls “stroads,” or street-road hybrids which perform neither function well.
Street connectivity. Roughly half of all trips made in the United States are three miles or shorter; 28% are one mile or less. But the prevailing development pattern since World War II has been to build disconnected subdivision pods or shopping-center pods off major corridors. Because of non-existent connectivity between adjacent pods, drivers funnel onto already-overcrowded connector roads and arterials even to make short trips. As a condition for accepting subdivision streets into the public road system, local governments should consider requiring minimal standards of connectivity with other developments. “The Innovative DOT” specifically notes connectivity reforms in Virginia implemented during the Kaine administration and partially reversed during the McDonnell years.
Access management. DoTs allow their roads — including, here in Virgninia, state highways — to fall into ruin by failing to limit access by neighboring property owners. As the manual observes, “A road can become a victim of its own desirability, as an ever-increasing number of private driveways and entrances to commercial establishments dot the highway. The increasing number of turning movements and vehicles entering a high-speed roadway leads to increases in crashes and congestion and premature calls for adding travel lanes to reduce traffic patterns.” The pattern in Virginia, epitomized by U.S. 29 north of Charlottesville but a problem everywhere, has been to add travel lanes and, then, when that option gets too expensive, to build bypasses. The solution, suggests the manual, is to establish an access management plan for a corridor that sets standards for accessing the road. Virginia has established such a plan to prevent the further ruination of U.S. 29, but I am not certain how well it is enforced.
Transportation Demand Management. Transportation Demand Management (TDM) attempts to alleviate congestion by focusing on the demand side of the equation, reducing demand for scarce roadway capacity by urging people to walk, bike, telecommute, carpool, van pool, ride mass transit and adopt flexible work hours. These efforts can be complemented through dynamic road pricing for roads, parking and transit, which raise the cost for driving solo during hours of peak demand. As it happens, Virginians need look no farther than Arlington County to see one of the nation’s most sophisticated TDM programs at work.
System management. System management solutions encompass an array of technology-oriented solutions to increase roadway capacity, such as traffic light synchronization, signage that alerts motorists to traffic conditions, rapid incident response to clear traffic accidents and ramp meters that control the rate at which vehicles enter a highway during periods of peak demand. This is an area where Virginia excels. The state has five state-of-the-art traffic management centers, it has installed traffic signage on all major highways, and it is investing heavily in technology upgrades to Interstate 66.
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