The case for the proposed Charlottesville Bypass is collapsing like an old bridge. Even a VDOT consultant questions how well Skanska-Branch’s design for the controversial highway can handle projected traffic loads.
by James A. Bacon
Suspicions confirmed: Northbound trucks on the proposed Charlottesville Bypass would take nearly two minutes longer to pass through the southern interchange under contractor Skanska-Branch Joint Venture’s preliminary design than under VDOT’s original design — nullifying much of the purpose of building the bypass in the first place.
The travel-time estimates come not from citizen activists opposed to the Bypass, whose concerns I have detailed on Bacon’s Rebellion (see “A Bypass for Trucks that Trucks Won’t Use.”) It comes from VDOT’s own consultant, Parsons Brinckerhoff.
A Jan. 17, 2013, draft memo from Michael Fendrick with Parsons Brinckerhoff included a chart that listed computer-modeled travel times through the interchange under various scenarios. Under the original VDOT design, which used a “flyover” ramp allowing for 45 mile-per-hour travel, trucks would take 58.3 seconds on average to clear the interchange. Under the “3 lane diamond” design, adopted by Skanska-Branch for purposes of actual construction, the trip would take 167.7 seconds on average.
“As would be expected, the flyover is the best from a traffic and operations perspective,” wrote Fendrick. “The 3 lane diamond with steep grades is substantially slower than the other alternatives due to signal delay plus truck acceleration issues.” Given the steepness of the grade, trucks would have to travel 1,400 feet before accelerating to 45 miles per hour.
The difference between the two designs is 110 seconds — offsetting much of the roughly 150-second travel-time savings the $244 million project was supposed to gain for north-bound trucks seeking to skirt a congested stretch of U.S. 29 north of Charlottesville. And that doesn’t include other problems identified by Parsons Brinckerhoff and VDOT officials in documents obtained by the Southern Environmental Law Center (SELC) under the Freedom of Information Act.
The Skanska-Branch design also would create a problem with a “weaving” traffic pattern between the southern terminus and the Ivy Road interchange on the U.S. 250 Bypass. Weaving occurs when traffic entering a limited-access highway from one interchange conflicts with traffic on the highway seeking to exit at the next interchange. When interchanges are closely spaced or when conditions are already congested, the complex pattern can slow traffic, worsen congestion and increase the risk of traffic accidents.
Furthermore, the three-diamond design would create problems for south-bound drivers where the two-lane Bypass would split as it approached the southern terminus and merged with U.S. 250. “From a capacity standpoint,” wrote Fendrick, “the merge will cause flow operation issues, particularly if the single lane to the right is at a low design speed.”
When the Commonwealth Transportation Board approved $244 million in 2012 to fund the project, VDOT displayed schematics from an earlier design in its presentation to the board. No one had informed board members that engineers in the Richmond central office were questioning whether the project could be delivered for that price. The McDonnell administration finessed those concerns by setting up the Bypass as a design-build contract on the expectation that outside, private-sector bidders might find creative ways to redesign the 6.5-mile highway at lower cost.
Skanska-Branch submitted a low bid of $135 million to handle design and construction — not including funds for preliminary engineering and Right of Way acquisition — coming in just under the authorized amount. The company’s conceptual design saved millions of dollars of construction costs by eliminating the southern-terminus flyovers, vastly reducing the amount of excavation, fill and new roadway construction work required. Despite the radical design changes — drivers now would encounter two stoplights on a steep grade — VDOT awarded the contract to Skanska-Branch.
A competing bidder, American Infrastructure, disputed the contract award, arguing that Skanska-Branch had failed to meet the specifications of VDOT’s Request for Proposal. In a June 1, 2102, letter to Jeff Roby with VDOT’s Alternate Project Delivery Office, the firm honed in on the southern terminus, specifically citing the problems created by the traffic signals, the weave traffic pattern, and the inability to handle large traffic volumes during special events at the nearby University of Virginia. Read more.
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