Travel Time Savings

   As shown in Figures 40 and 41 one of the notable benefits of using Northern Virginia’s HOV facilities is the substantial reduction in travel time over non-HOV travel. The HOV lanes usually move at speeds approaching the speed limit, while the parallel conventional lanes move at much slower speeds due to congestion. Survey data show that morning commuters using the HOV lanes shave about one half-hour off their commute on I-95/I-395 and I-66 and about 20 minutes off their commute on the Dulles Toll Road in comparison to commuters in the parallel conventional lanes[J1] .  Furthermore, commute time is more predictable in each of the corridors for those who choose the HOV lanes.[10]

A 1999 study by the COG/TPB showed that during the afternoon peak commute the average speed in the HOV lanes on I-95/I-395 between the Virginia end of the 14th Street Bridge and Joplin Road (VA 619) in Prince William County, a distance of about 27.3 miles, reached 60 mph.  In the parallel conventional lanes, it took commuters 133% longer to travel the same distance at an average speed of 26 mph.  In other words, commuters using the HOV lanes saved 36.5 minutes or 1.34 minutes per mile during their afternoon commute. The study also shows significant travel time savings in the HOV lanes on I-66 and the Dulles Toll Road (VA 267). 

The Texas Transportation Institute estimates that the average auto commuter in the Washington DC metropolitan area suffers 84 hours of peak period delay annually due to congestion on the region’s freeways and major roadways.[11] Using a different methodology than the COG/TPB HOV performance study, the TTI calculates mobility levels for specific HOV corridors. [12] The results show even greater time savings for commuters using the HOV lanes. Commuters on a 55-mile section of I-95/I-395 save over one hour, commuters on a 34-mile section of I-66 save more than 30 minutes, and those who choose the HOV lanes on the Dulles Toll Road save nearly one-half hour. Clearly, commuters who take advantage of the region’s HOV lanes by traveling in vanpools, carpools or on transit can save many hours annually from their commutes.

Source:       1999 Performance of Regional High-Occupancy Vehicle Facilities on Freeways in the Washington Region: An Analysis of Travel Times. Final Draft. National Capital Region Transportation Planning Board of the Metropolitan Washington Council of Governments (October  6, 2000).

 * HOV travel time savings is more reliable inside the Beltway than outside the Beltway. For the eastbound A.M. peak period, the standarD deviation of elapsed travel times in the HOV lanes is 1 minutes 46 seconds for the inside-the-Beltway portion of the run and 5 minutes 36 seconds for the outside-the-Beltway portion.