Centreville's Pleasant Valley/Braddock Road intersection at rush hour is a giant pain. So VDOT's considering installing a roundabout there.
And Tuesday night, VDOT Area Engineer Laura Hegler gave a video presentation while telling the West Fairfax County Citizens Association (WFCCA) Land-Use Committee how it would operate.
"We feel it's the best fit for the intersection," she said. "It would be something with a center island that accommodates a school bus and has about 16 feet of driving width."
There'd be no left turns at that intersection; every vehicle would turn right to enter the circle. Coming from Virginia Run on Pleasant Valley Road, drivers would encounter a triangular island to slow traffic, with a raised circle in the middle, about 100 feet in diameter.
Hegler said peak-hour traffic volume justifies it at that spot and a roundabout "really improves safety and operates [more] efficiently" than the four-way stop currently there. She said approaching motorists would yield to whoever's already in the roundabout. Then, once traffic passes, other drivers could enter to the right.
Yet citizens and WFCCA members had serious concerns whether a roundabout would be beneficial there and, if it was, who would it really help? Would it mainly enable Loudoun County residents to travel through there easier, at the expense of local, Fairfax County residents forced to wait in line until Loudoun drivers were out of the circle?
"I live a couple hundred yards from that intersection, and it's very difficult to make a right turn out of our neighborhood now because it's the back door to the Westfields business community," said WFCCA's Chris Terpak-Malm. "[With a roundabout], we're afraid we'll never be able to get out of our neighborhood in the morning rush hour."
Hegler replied that "we can control those entry points so that there'd be enough gap [to allow drivers] to enter the roundabout, so they'd be forced to slow down to let you in." But, said Terpak-Malm, "If you're pushing traffic through, my concern is that you won't then be concerned about the 45 homes in the neighborhoods that can't get out of their driveways." Answered Hegler: "That is a valid concern."
WFCCA's Dorothy Steranka noted that Hegler's presentation was based on 1,600 vehicles per hour going through that intersection in 2003. But, she said, "The counts have increased so much because of all the building." Agreeing, Hegler said VDOT would conduct new traffic counts this fall.
WFCCA's Dawn Williams asked if the counts would factor in all the new homes to be built in Loudoun, and Hegler said she'd check. With both Loudoun and Fairfax County homes and the Fairfax County Park Authority developing 10 soccer fields on the nearby Stevens property, added Terpak-Malm, "A mom will drop off her child there and won't be able to make a left turn to get out."
Hegler responded that, "Even if we do this [roundabout], it may not be forever. It may be interim to a traffic signal in the future." At-Large Planning Commissioner Jim Hart worried VDOT might assume there'll be equal growth in all directions when, in fact, "north, south and east are pretty stable."
But, he warned, "The Loudoun side is a very different dynamic. Besides all the homes in South Riding, there'll be many more thousands of homes going west on Braddock. There's one application in now for 1,800 units right on the line — more than the existing [Fairfax County] homes there now."
"Does the roundabout over-favor cars — which will be from Loudoun — already in the traffic circle?" asked Hart. "Is there ever a break to let us in?" Hegler said VDOT's current software can't answer that question, and Hart said a break is "essential."
Also wondering about capacity, he asked if there's a "tipping point" of number of vehicles "where this couldn't handle the volume and something else would be needed. Even if it kinda worked now, would the new homes in Loudoun overwhelm it?"
If that happened, said Hegler, she'd then recommend a traffic signal. Stephen Vandivere of Cabell's Mill couldn't envision a roundabout working "if the traffic volume was much larger on one street than on the other." And, admitted Hegler, "During rush hour at this intersection, traffic will still be bad, even with a roundabout."
Pleasant Valley's Cynthia Shang and Eric Cox of Cox Farms favored it over a traffic signal. But, said Bull Run Estates' Mark McConn, "You make it more efficient for Loudoun County [residents] to drive through, and more of them will. The volume from Loudoun will overtake this even before it's built."