'Zipper merge' speeds construction zone traffic; don't screw it up

Written by Jon Schmitz on .

merge2Traveling on Racetrack Road in North Strabane last week I happened upon a lane restriction at Route 19. The left lane, the only open lane, was backed maybe a tenth or two of a mile and everyone had pretty much merged early, leaving a long stretch of the right lane clear in advance of the merge point.

Trying to make sure that no one took advantage by driving up the clear right lane, two self-appointed guardians of fairness and justice pulled their vehicles so as to straddle both lanes.

This is when I yearn for a bazooka. Using both lanes to the merge point, then taking turns (called a “zipper merge”) speeds things up by 15 to 20 percent compared with everyone crowding over well in advance of the merge point. It makes sense to use all of the available road capacity in advance of a work zone. The “zipper merge” was pioneered by PennDOT and has been copied in other states.

Merging early slows things down. You want to do the dumb thing, go ahead. You have no right to force everyone else to follow suit.

ICYMI, today’s Post-Gazette previews the upcoming Squirrel Hill Tunnel closure and some other traffic restrictions that are on the horizon. And there’s more, as PennDOT races to get as much work in as possible before winter sets in.

The westbound Parkway East will have single-lane traffic between Grant Street and the Fort Pitt Bridge starting at 9 p.m. Monday through Thursday for sign installation. Work concludes by 5 a.m.

The ramp from Grant Street to the westbound parkway will be closed at 9 p.m. Monday and Tuesday, as will the ramp from the westbound parkway to Stanwix Street. Then, on Wednesday and Thursday, the ramp from Stanwix Street to the westbound parkway will close at 9 p.m., and a lane will close on the off-ramps from the westbound parkway to Grant Street and the off-ramp from the Fort Pitt Bridge to Commonwealth Place. All restrictions lifted by 5 a.m. daily.

Work on the ramp from Grant Street to the outbound Parkway East will keep it closed through Oct. 18.

Full inbound closures of Route 28 at Millvale start at 8 p.m. Monday through Wednesday, with traffic using the off- and on-ramps to get around the milling and paving area. Work ends by 5 a.m. daily.

The inbound Liberty Tunnel will have a lane closed starting at 9:30 p.m. Tuesday and Wednesday. It reopens by 5:30 a.m.

Crack and joint sealing will cause lane closures on Route 51 between the Elizabeth Bridge and Practice Tee Drive in Jefferson Hills after 7 p.m. daily through Oct. 16. Work will conclude by 6 a.m. daily.

Drilling of core samples on Penn Avenue between Broad Street and Highland Avenue in East Liberty will cause intermittent lane closures from 8 a.m. to 3 p.m. Tuesday.

More drilling will occur on Route 8-Washington Boulevard between One Wild Place and Highland Drive-Leech Farm Road, causing short-term lane closures from 8 a.m. to 3 p.m. Monday.

Installation of an overhead sign will cause traffic shifts and brief stoppages at times at Marshall and California avenues, North Side, from 8 a.m. to 5 p.m. weekdays starting Tuesday through mid-November.

Rail grinding on Arlington and Warrington avenues will continue Monday and into mid-October, with alternating single-lane traffic in the work area.  

The on- and off-ramps connecting Grand Avenue to northbound Interstate 79 and the Neville Island Bridge will have short-term lane and shoulder closures from 9 a.m. to 3 p.m. daily through Friday for washing.

On Connor Road between West Franklin and Sunridge drives in Mt. Lebanon, intermittent lane closures are possible from 8 a.m. to 3 p.m. Tuesday and Wednesday as crews take core samples for a future project.

Core drilling for a future improvement project at the bridge over Little Pine Creek on Saxonburg Boulevard in O’Hara will cause alternating one-way traffic between Kay Drive and Berryhill Road from 9 a.m. to 3 p.m. on weekdays through Oct. 26.

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