Transportation Planning

Transportation Planning

Planning vs. Execution

Many of us assume our traffic woes are the unavoidable result of job and population growth in the area. Or perhaps it was a failure to adequately plan for that growth. Neither assumption, however, is accurate.

Today’s regional highway and bridge network constitutes a relatively small portion of the comprehensive system that professional planners in the mid-1960s proposed for the area by the year 2000. In other words, we knew what was going to happen; we even planned for it (three decades in advance!). The real problem is this: we failed to follow through on the known plans to accommodate our known growth. Many planned highway and transit enhancements were deleted from official plans or never built because elected officials believed, “if we don’t build roads, people won’t come.” But the people and jobs came anyway.

Since the mid-1960s most of the planned Metrorail and commuter rail facilities have been built. The result: The nation’s second most successful mass transit system in terms of people moved per 1,000 population. (That’s Good)

During this same time period more than 1000-lane miles of planned freeways have been removed from area maps. Thousands of additional lane miles of planned primary and secondary road improvements have been eliminated or delayed. The result: One of the nation’s smallest road networks per 1000 population and the second most congested. (That’s Bad)

Less Roads = More Congestion

The metropolitan Washington area is the nation’s 8th most populous but ranks 30th in terms of its ratio of miles of roads per thousands of people.

Land Use & Transit-Based Development

What about land use policies and transit development? Will that successfully alleviate DC’s traffic congestion?

The NVT Alliance supports land use policies that encourage higher density, mixed use development near intersecting highway and rail corridors and public transit hubs to maximize transportation investments and better focus projected population and employment growth.


Land use and public transit alone are not adequate substitutes for planned transportation investments.

It is fashionable today to promote the notion that land use alone should dictate transportation policy and that transit-oriented development is the ultimate solution to transportation and land use issues. Organizations like the Sierra Club, Coalition for Smarter Growth, Piedmont Environmental Council, etc. and their followers have waged an aggressive campaign to convince elected officials that land use policy changes can largely eliminate the need for new transportation infrastructure capacity — with the possible exception of rail extensions and buses. In fact, far from precluding the need for transportation investments, planners have long recognized that a well-articulated transportation structure of roads, bridges and public transit is key to better mobility and land use.

“The urban region can be looked at as a group of land use cells, defined by the transportation network…”
—The Regional Development Guide 1966-2000

“Radial freeway interchanges and rapid transit stops (planned to be in place by 2000)… would serve as ‘nodes’ or intensive centers of commercial-office-industrial activity… Two additional beltways are proposed. By allowing circumferential freeway interchanges to connect only with radial freeways, flexibility of movement is promoted and the wedges and corridor (open space protection) concept is strengthened.”
—National Capital Regional Planning Commission, June 1966

Transit-Oriented Development Is Only a Partial Solution

The American Public Transportation Association defines transit-oriented development as compact, mixed use development near new or existing public transportation infrastructure that serves housing, transportation and neighborhood goals. Its pedestrian-oriented design encourages residents and workers to drive their cars less and ride mass transit more. The Alliance has always supported land use policies to maximize growth around public transit infrastructure, but recognizes that such focus is insufficient given existing and future settlement patterns that are not oriented towards or focused around public transit.

National Capital Region Transportation Planning Board (TPB) studies show:

  • Between now and 2040 most new population and job growth will occur beyond the Capital Beltway.
  • More than 80% of all daily trips will continue to be by automobile.
  • Only about 7% will be by public transit.
  • 71% of all existing and future jobs in metropolitan Washington area are and will be located in major activities served by existing major transportation (road and transit) corridors.
  • 31% of all housing is currently located in a similar manner.
  • By 2030, the region is projected to add:
    • 1.6 million more people (+33%)
    • 1.2 million more jobs (+40%)
  • 80% of the homes/offices/stores that will exist in 2030 are in place today. Of the remaining 20%: Half is in the pipeline and unlikely to change. A quarter or more is likely to follow existing patterns. The remaining quarter might be re-focused near transit or highway hubs.

A study by the Hampton Roads Planning District Commission (Hampton Roads’ TPB counterpart) that incorporated aggressive land use and public transit strategies concluded that land use and public transit alone are not adequate substitutes for planned transportation investments:

“An HRPDC Smart Growth Study released in 2003 concluded that, while aggressive ‘Smart Growth’ strategies would reduce (2026) congestion and emissions (levels), no planned improvements could be removed for the 2026 Long Range Transportation Plan.”
—Hampton Roads Planning District Commission, December 2005

Looking Forward

  • The region currently has the nation’s second worst congestion.
  • Between 2015 – 2040 the region is projected to add:
    • Another 1 million vehicles & 4.1 million vehicular trips per day.
  • In 2040:
    • 80% of daily trips will be by automobile
    • 13% by walking and biking
    • 7% by public transit
  • The region’s current, long-range plan increases capacity about 7%, while congested lane miles will increase by 71%.


From this data, several conclusions are clear

  • Building the missing transportation links endorsed by the Alliance is critical to both better mobility and better land use.
  • Employing the best land use practices and focusing higher commercial and residential densities around major existing and planned road and transit corridors will make such transportation investments work better, but are not substitutes for such investments.
  • Land use changes alone will have little significant impact on the overall future regional totals for daily trips, miles of travel, or congestion in general.
  • Land use changes may marginally improve mobility and accessibility in select corridors or activity centers over what it could be in the future, but certainly not over current conditions.
  • New highway and transit capacity do far more than land-use-alone strategies to reduce congestion and delays and improve travel times and reliability.