Drivers heading south on Beacon Street will face a new lane assignment this summer after the Andover Select Board unanimously approved a traffic pattern change at the Beacon Street, Lowell Street and Shawsheen Road intersection on Monday, July 13.

Under the amended rules, the left lane will become a left-turn-only lane onto Lowell Street. The right lane becomes a shared lane for right turns and straight-through traffic. That's a reversal of the current setup, where the left lane handles both left turns and through traffic while the right lane is right-turn only.

Safety Officer Glen Ota told the board the change addresses southbound queuing that has backed up traffic on Beacon Street. "It's very simple, just pavement markings and some new signs and that's it," Ota said at the July 13 meeting.

The fix has been years in the making. Ota said the town hired Somerville-based engineering firm Design Consultants Inc., known as DCI, around 2020 to study the intersection. DCI's recommendation to flip the lane assignments was later reviewed by a transportation working group before the town decided to move forward. No changes to traffic signals or their timing are involved.

Ota said the Beacon Street change was advanced now to ease congestion before more modifications arrive as part of the larger Route 133 corridor project, a 1.25-mile reconstruction stretching from West Parish to Shawsheen Village. That project carries a $15.2 million commitment from the state and federal Transportation Improvement Program. The Andover Townsman and Andover News report the funding is allocated for fiscal year 2029, though the town's official project page lists fiscal year 2028.

The corridor reconstruction will include a shared-use path for pedestrians and cyclists, traffic signal upgrades, stormwater drainage improvements, added turning lanes and accessible curb ramps, according to the town's project page.

Select Board member Kevin Coffey raised a similar congestion problem on the Haverhill Street approach to Shawsheen Square, where drivers heading straight get stuck behind left-turning vehicles because of a right-turn-only lane. Coffey said the plan is to address that intersection as part of the corridor project. Public Works Deputy Director Arthur Martineau explained that civil engineering firm TEC, the corridor project's consultant, advised that creating a left-turn-only lane at Shawsheen Square would not improve functionality there and could make things worse.

Before the new Beacon Street pattern takes effect, message boards will go up on the road approximately one week in advance, Ota said. Police officers will also be stationed on Beacon Street to monitor the transition.