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Mobility Project - State-by-State Analysis of Future Congestion and Capacity Needs - District of Columbia

August 1, 2006


How bad will traffic congestion be in 2030? How much construction and how many new lane miles will each state and major city need to add over the next 25 years to prevent severe congestion? And how much will it all cost? The Reason Foundation study Building Roads to Reduce Traffic Congestion in America's Cities: How Much and at What Cost? and its addendum, A Detailed State-by-State Analysis of Future Congestion and Capacity Needs, provide in-depth answers to these questions. An interactive map ranking the states by congestion and costs to reduce traffic is here and a map of the most congested cities is here.


District of Columbia

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To significantly reduce today's severe congestion and prepare for growth expected by 2030, Washington, DC needs just over 1,800 new lane-miles at a total cost of $16 billion, in today's dollars. That's a cost of $127 per resident each year. Washington, DC ranks 18th out of 50 states and the District of Columbia in terms of most lane-miles needed and ninth in the total cost of those improvements. If the region made these improvements, it would save 428 million hours per year that are now wasted in traffic jams.

Washington, DC is the fourth most congested city in the United States, where the Travel Time Index (TTI) is 1.51. This means that driving times during peak traffic hours are 51 percent longer than during off-peak times. The only regions that experience worse traffic are San Francisco (1.54), Chicago (1.57), and Los Angeles (1.75).

However, unless major steps are taken to relieve congestion, drivers in the nation's capital can expect to see a TTI of 1.87 by 2030, meaning they will experience travel delays worse than present-day Los Angeles.

The District of Columbia region could significantly reduce congestion by adding about 1,800 new lane-miles by 2030 at an estimated cost of $16.2 billion in today's dollars. This includes the costs of adding 4 percent of the new capacity by building elevated roadways and tunnels, which will be necessary in a densely settled location like Washington.

This investment would save an estimated 428 million hours per year that are now lost sitting in capital city traffic, at a cost of just $1.52 per delay-hour saved. This does not account for the additional benefits not quantified in this study, including: lower fuel use, reduced accident rates and vehicle operating costs, lower shipping costs and truck travel time reductions, greater freight reliability, and a number of benefits associated with greater community accessibility, including an expanded labor pool for employers and new job choices for workers.

While $16.2 billion may sound like an unattainably large investment, it is actually only 17 percent of the amount that the DC area's Metropolitan Planning Organization (MPO) already plans to spend in their long-range transportation plan. The Metropolitan Washington Council of Governments (MWCOG) plans to spend approximately $93.3 billion during the next 25 years� $36.9 billion on highway improvements and $56.4 billion on mass transit. While transit spending constitutes 60 percent of the budget, only about 11.2 percent of DC commuters now use mass transit. While some of the planned highway improvement funding may be used for capacity expansion, the majority is often allocated to preserving, maintaining, and operating the highway system.

(click here for larger image)

» Return to Index Page: Study, State-By-State Data, Maps
» Return to Interactive Map of Traffic U.S. Congestion Statistics and Construction Needs

This information is excerpted from A Detailed State-by-State Analysis of Future Congestion and Capacity Needs and Building Roads to Reduce Traffic Congestion in America's Cities: How Much and at What Cost?

Additional Resources:
» Reason Foundation's Mobility Project Main Page
» Reason Foundation's Transportation Research and Commentary
» Reason Foundation's Press Room

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