Gainesville bridge

The major transportation improvement of the summer is about to occur in Gainesville. The Virginia Department of Transportation plans to shift Route 29 traffic onto the new bridge that will separate drivers on this busy commuter route from the railroad crossing.

This is also an important route for people going to the Jiffy Lube Live venue a mile away, and it was the prospect of crowds for the sold-out Jimmy Buffett concert on Saturday night that caused VDOT to postpone the traffic switch from this weekend to next.

So avoid that area next weekend, because traffic delays of as much as an hour are very likely during the switchover operation. From 9 p.m. Friday to noon Sunday, only one lane in each direction will be open on Route 29 and Linton Hall Road, and some turns will be restricted.

I-95 closing

Drivers in Virginia should also note another big project scheduled for this coming weekend: Overnight Friday, VDOT plans to close the regular lanes on Interstate 95 South at the Fairfax County Parkway. Workers will place a 500-ton steel box beam to support a flyover ramp for the new 95 Express Lanes.

The lanes will start closing from the right at 9:30 p.m., and by 1 a.m. the entire southbound side will be shut. The lanes should all be open again by 9 a.m. Saturday.

Through traffic will be detoured onto the HOV lanes by a left-side ramp just south of the Springfield interchange. Local traffic will be directed to Fullerton/Backlick Road (Exit 170).

If there’s a problem with the weather, then the closing will be rescheduled for overnight Saturday.

New lane hours

The express lanes project is having the biggest effect on travel of any road work in the D.C. region this summer. It affects traffic along 29 miles of I-95/395 between Edsall Road, just north of the Capital Beltway, and Garrisonville Road to the south.

The HOV lanes on northbound ­I-395/95 in Virginia now close at 10 a.m. rather than 11 a.m. weekdays, and the southbound HOV lanes open at noon rather than 1 p.m.

The change will remain in effect until mid-October, VDOT said. Transportation officials hope this will ease southbound congestion during construction of the 95 Express Lanes and the I-95 shoulder lane project in Prince William County.

Into the fall, watch for: extensive lane closings and delays at off-peak hours day and night, occasional full closings of I-95 and overnight detours, slow-moving trucks entering and leaving the work zone in the median, reduced access to shoulders.

Transit center

While the long-delayed Silver Spring Transit Center has no opening date in sight, one part of the project is operational: A traffic signal at the center’s blocked-off entrance on Colesville Road has been activated.

During a recent online chat, a driver wrote in to complain that this added insult to injury for commuters. It’s tough to tell now, in the midst of the summer traffic lull, what long-term impact the signal will have on drivers.

But it is a plus for pedestrians, who are plentiful in this area just east of the Silver Spring Metro station entrance. They have a safer way of getting across wide Colesville Road thanks to the new mid-block crosswalk controlled by the signal.

Comments deadline

The regional Transportation Planning Board’s approach to drawing up regional priorities recognizes the need for the public to support the priorities that will be recommended to planners and politicians.

The month-long public comment period on the draft Regional Transportation Priorities Plan, featured on the Commuter page July 28, will close Friday.

You can comment online about ­­the proposed goals and strategies by ­following this link:

There’s also a phone line for public comment: 202-962-3262.

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