You can now read 10 articles in a month for free on BostonGlobe.com. Read as much as you want anywhere and anytime for just 99¢.

The Boston Globe

Metro

starts & stops

Braintree Split delays will last indefinitely

globe file

A typical Friday afternoon has traffic backed up along Route 128/Interstate 95 south in Westwood.

The Braintree Split is rarely any fun at rush hour, but it has been especially sluggish lately for those coming from Route 128 South — also known, naturally, as Interstate 93 North — heading for Route 3 South.

First, drivers going from Route 128 South onto Route 3 are being forced to merge into a single lane sooner, reader Sandra Perry notes. Then, once onto Route 3, Perry finds that the three southbound lanes have mysteriously narrowed and shifted to the right, eliminating the breakdown lane for a few hundred yards.

Continue reading below

“Is there some construction taking place here? What is to be the final resolution? How long will it take?” she asks. “I am not too happy to be in a big tie-up on 93/128 at the split, whether I leave work at 4 p.m. or 7 p.m.”

The culprit is a degraded secondary steel support to one of the main steel girders elevating Route 3 over the Thomas E. Burgin Parkway near the Braintree-Quincy line, with the problem discovered on a recent state inspection, said Michael Verseckes, a Department of Transportation spokesman.

To shift the weight of traffic to the sturdier side of the highway, the state closed the left lane and opened the right shoulder. To accommodate that shift, workers also narrowed two lanes to 11 feet and one lane to 10 feet, from the standard 12-foot width.

And because of those changes, the state made the adjustment that Perry noticed on the Route 3 merge. That ramp, newly and narrowly striped, was always supposed to have one lane but is wide enough for drivers to treat it as two, Verseckes said.

“It’s causing a lot of frustration. Believe you me, we hear them loud and clear. It’s not something we like to subject people to intentionally,” Verseckes said. “But if inspection results say ‘get people off this beam,’ that’s what we’re going to do.”

And now for the bad news: The change is indefinite. State engineers are still determining how best to shore up the degraded steel on a temporary basis, as a prelude to more lasting repairs, Verseckes said.

New road rules

Last week’s column answered a question from reader Robert L. Mayer of Chestnut Hill, asking if bicyclists are required to stay within bike lanes on roads that have them. (They are not.) That reminded me of an earlier e-mail from reader Peggy Carlan of Chelsea, who asked for help interpreting other bike-related road markings popping up all over Boston and other urban communities of late.

“The bike lanes are clear enough, but when I saw the markings for shared lanes I had no idea what they meant, and even thought they might indicate no bikes allowed,” Carlan wrote.

The question is a good one for all of us whose driver’s ed days predate the proliferation of road markings to encourage and protect bicyclists.

The markings Carlan specifically asked about are known as “sharrows” — bike icons framed by symbols that look like boomerangs, painted directly on roads lacking bike lanes. They are meant to call attention to riders on roads that lack sufficient width for bicycle lanes but still carry heavy bike traffic.

Kris Carter, interim director of the city’s Boston Bikes program, explained two other new roadway markings:

The Bike Box: Large green boxes with bike icons, now found on Commonwealth Avenue intersections and other locations. They provide the cyclist a safe space to wait ahead of cars at a red light, to reduce the possibility of drivers taking a right turn into the path of bicyclists.

The Priority Shared Lane: These are dashed bike lines that contain sharrows that the city is piloting this year on Brighton Avenue in Allston. They indicate that the road cannot fit a fully painted bicycle lane but that bike traffic is heavy enough to merit something more than regular sharrows.

When bikes are present, the dashed line should be treated as a solid line, giving the bike priority.

In considering when, how, and where to mark streets for bicyclists, the city works with the Boston branch of Toole Design Group, a national planning and design firm. The city is working with Toole to ensure “good, well-thought-out improvements” to the Huntington Avenue corridor and specifically the Huntington-Forsyth Street intersection, site of a fatal June 1 bicycle accident, Carter said.

Eric Moskowitz can be reached at emoskowitz@globe.com.

You have reached the limit of 10 free articles in a month

Stay informed with unlimited access to Boston’s trusted news source.

  • High-quality journalism from the region’s largest newsroom
  • Convenient access across all of your devices
  • Today’s Headlines daily newsletter
  • Subscriber-only access to exclusive offers, events, contests, eBooks, and more
  • Less than 25¢ a week