Freeway Management > Lane Management > Variable Speed Limits

>> Benefits Documents

On the Køge Bugt Motorway in Copenhagen, Denmark, variable speed limits reduced vehicle speeds by up to 5 km/h and contributed to smoother traffic flow during peak periods.(8 April 2003)

A survey of motorists in Copenhagen, Denmark, found that 80 percent of respondents were satisfied with variable speed limits and the traveler information posted on dynamic message signs.(8 April 2003)

A study of travelers on Snoqualmie Pass, WA found that DMS can decrease mean driving speeds and reduce accident severity.(December 2001)

It was estimated that variable speed limit signs and lane control signals installed on the autobahn in Germany would generate cost savings due to crash reductions that would be equal to the cost of the system within two to three years of deployment. (August 1999)

Advanced traffic management systems in Amsterdam and Germany reduced crash rates by 20 to 23 percent.(August 1999)

>> System Costs Documents

A variable speed limit system consisting of multiple ITS components and covering 40 miles over the Snoqualmie Pass in Washington was designed and implemented for $5 million.(November 2001)

>> Lessons Learned Documents

Deploy a variable speed limit system only after the software systems required to support it are mature and reliable. (01/30/2009)

Enable and enforce managed lane facilities using various ITS tools.(January 2003)