capacity

New study finds that road closures can alleviate congestion in dense urban areas

By Chet Edelman Historically, transportation policy addressing vehicle congestion has entailed increasing road capacity—whether it be through widening existing roads or building new roads altogether. However, research consistently reveals that these policies have the opposite effect. Rather

LA drivers wonder whether expanding the 405 was worth it

By Bill Holloway After years of construction headaches and a $1.6 billion investment, the Sepulveda Pass project, which expanded Interstate 405, the nation’s busiest highway, appears to have had a minimal impact on congestion. The project, which added carpool lanes, on- and off ramps, and three

Automated vehicles will bring big highway capacity increases

By Eric Sundquist As the transportation field grapples with the impending impacts of automated vehicles, one AV-related outcome seems clear: Highway capacity will dramatically expand. One new estimate comes from Dwight L. Farmer in the November ITE Journal (paywall). Because automatic braking

New Jersey DOT: no more roadway expansions

By Dan Handel Richard Hammer, New Jersey’s newly appointed Department of Transportation Commissioner, announced the agency will pursue a ‘fix-it-first’ mindset toward transportation spending. “The days of system expansion in New Jersey are long over, we don’t have the funds,”

Highway capacity won’t relieve congestion or lower emissions, studies conclude

By Eric Sunquist A commonly cited strategy to achieve lower emissions and energy use is highway capacity expansion intended to reduce delay. Such a strategy, which has justified many a CMAQ project, is straightforward and appealing to motorists who dislike traffic. But, as a new brief from

One-way or two-way streets more efficient? It depends on what you measure

By Chris Spahr The debate over one-way versus two-way streets has been ongoing for more than half a century in American cities. Counter to prevailing engineering wisdom, a new study finds two-way streets may be more efficient, if one is measuring getting people to their destinations. Many cities

Linking Community Visioning and Highway Capacity Planning (Strategic Highway Research Program, 2012)

This report is intended to help transportation agency practitioners assess the possibilities of community visioning efforts, identify practical steps and activities when engaging in visioning, and establish links between vision outcomes and transportation planning and project development

Gas consumption down to 2000 levels

Better vehicle fuel-efficiency and moderating demand for highway travel are combining to push gasoline consumption down. U.S. gasoline consumption is on pace to drop to its “lowest levels since Elian Gonzalez was at the top of the news, Time Warner was heralding the synergies of its AOL

More roads, more traffic, really dreary news.

Many analyses of road network expansion and congestion have challenged the notion that increasing highway capacity relieves traffic. A recent study of American cities emphasizes that you can’t build your way out of congestion. The analysis by Professors Gilles Duranton and Matthew Turner of the