Traffic Study Renews 'Techway' Debate
Most Md. Drivers Who Cross Legion Bridge Turn West, Researchers Find
By Steven Ginsberg
Washington Post Staff Writer
Tuesday, May 11, 2004; Page B01
A study of traffic on the American Legion Bridge, released yesterday by Virginia transportation officials, has revived debate over the need for a new Potomac River crossing west of the Capital Beltway.
The study found that nearly two-thirds of Maryland commuters head west to job centers once they enter Virginia, while a similar number of Virginians turn east to destinations inside the Beltway once they cross into Maryland. The numbers also show that thousands of drivers make a horseshoe commute between the western suburbs of both states.
Virginia Department of Transportation officials said the $122,000 study was designed solely to give planners a sense of traffic patterns at one of the region's worst choke points.
But VDOT planners also acknowledged that the information could bolster arguments for building a bridge across the Potomac west of the Beltway, often referred to as the "techway" because it would link the Dulles and Interstate 270 technology corridors. VDOT officials added that the study was prompted by Reps. Thomas M. Davis III (R-Va.) and James P. Moran Jr. (D-Va.), both backers of another bridge.
The idea of building another Potomac crossing west of Washington has been hotly debated for years. Proponents say another bridge is needed to serve evolving suburb-to-suburb commuting patterns and relieve congestion on the Beltway, I-270, Interstate 66 and other major roads.
Opponents counter that a new bridge would do little more than promote another wave of suburban sprawl that would soon overburden the new span.
The idea slipped into the background three years ago, when Rep. Frank R. Wolf (R-Va.) asked the Federal Highway Administration to cancel a $2 million study he had requested after it prompted a fierce backlash among many of his constituents.
Supporters said the results of the recent study give them another opening.
"The report tells us where people are coming from and where they're going," said David Marin, a spokesman for Davis. "Without that ammunition, you can't even make the case, let alone a well-informed decision, about a new river crossing."
Marin said the report proves that commuters are "traveling from Gaithersburg out to the Dulles corridor." He said Davis will use it to "push forward the idea of the need for a new river crossing."
Opponents of a techway also found things to like in the study.
Stewart Schwartz, executive director of the Coalition for Smarter Growth, said the study "reinforces the fact that the techway is not needed" because "the vast majority of commuters crossing the bridge are going near the Beltway and inside the Beltway, not outbound" to points west.
"Tysons Corner is right on the Beltway," Schwartz said, taking issue with the study's classification of Tysons as a western suburb.
The information was gathered during several mornings last fall between 6 and 9 a.m. by placing infrared cameras on bridges, light poles and other spots to photograph license plates.
The cameras snapped the same cars on both sides of the bridge, which connects Fairfax and Montgomery counties. Agencies in Virginia and Maryland matched the plates to the Zip codes where the cars were registered.
Not all plates were photographed, and many were from states outside the area.
Of the 11,234 matched Virginia plates, 7,130 drivers, or 63 percent, traveled east toward Bethesda, Silver Spring and Interstate 95, while 4,104, or 37 percent, turned toward the I-270 corridor.
Of the 12,229 Maryland plates tracked, 7,929 drivers, or 65 percent, drove west of the Beltway once they entered Virginia, while 4,300, or 35 percent, went east.
A total of 2,757 Maryland drivers, or 23 percent, originated in the I-270 corridor, headed east to the Beltway and turned back west once they hit Virginia. This sort of horseshoe commuting pattern has been one of the arguments used by supporters of a techway.
Far fewer drivers from Virginia followed the same pattern. About 10 percent of commuters from Virginia started in the western suburbs and traveled to the I-270 corridor. More than three-quarters of Virginia commuters from the western suburbs end up east of the Beltway in Maryland -- a pattern that techway opponents said would be better served by proposed new Metrorail lines in both areas.
© 2004 The Washington Post Company