It's not just Orange Line riders who are expected to see significant disruptions and delays to their commutes over the next month. In a press briefing Monday morning, Gov. Charlie Baker and transportation officials made it clear the impact of the monthlong Orange Line shutdown will be broadly felt across Greater Boston.

"All roadway users — whether you drive, bike or walk — you will see changes in your everyday commute, and your commute will likely be longer in these areas," warned state highway commissioner Jonathan Gulliver. "All roadway users will start to see and should expect to be impacted by this work starting as early as today."

Gulliver explained much of the disruption will be the result of road changes made to accommodate the shuttle buses that will temporarily replace Orange Line service. Those changes include temporary bus lanes and parking restrictions. In some places, Gulliver said the adjustments will effectively cut roadway capacity in half.

"This means that traffic congestion will grow throughout the region and will be evident on interstates, numbered routes and connected local roadways," he said. "And this includes a number of key intersections like Charles Circle, Leverett Circle and Sullivan Square. Travelers along 93, Route 1 and the Fellsway should especially expect some additional traffic congestion — in some periods, as much as 20 percent."

A large map of Boston and surrounding cities is shaded in red to show the large area where traffic will worsen during the Orange Line shutdown.
A map displayed a Monday's press conference illustrated where the impacts of the Orange Line shutdown will be felt
Craig LeMoult GBH News

Boston Chief of Streets Jascha Franklin-Hodge said the city yesterday installed the first of several temporary bus lanes to support Orange Line shuttle buses.

"Over the coming days, we will undertake an unprecedented effort to reconfigure streets in ways big and small to ensure that the shuttle buses can operate safely and efficiently on Boston streets," he said.

That includes adding bus lanes and making signal adjustments at various points along the shuttle route. Franklin-Hodge said the city will also be putting parking restrictions in place to create adequate space for buses to line up and load passengers.

"We're analyzing the shuttle route to make sure that buses can safely travel and turn, especially on those streets that don't normally accommodate bus traffic," he said. "This analysis is resulting in numerous small adjustments that will help smooth out shuttle movements and keep it keep the streets safe for all users of the road."

The full 30-day closure of the Orange Line from Oak Grove to Forest Hills will begin at 9 p.m. this Friday, Aug. 19, and continue through Sunday, Sept. 18.

The MBTA has released a Rider's Guide to Planning Ahead, which outlines how replacement transit options are going to work. Boston also established its own website to help riders.

A sign with a bright orange border says "No Orange Line Service" and illustrates alternative options at various stops along a train route.
A sign displayed at Monday's press conference, similar to what Orange Line riders will see for a month
Craig LeMoult GBH News

Transportation officials are urging people to shift their travel routes or times to avoid disruptions. They also encourage people to commute by bike, if possible, and take advantage of free 30-day passes for Blue Bikes. But Gulliver had a warning for bicyclists and pedestrians to be careful near the replacement shuttle buses.

"The shuttle buses that are being implemented here are not the same as MBTA buses," he said. "They have different turning radius and they have different blind spots for drivers. If you are walking or biking near the shuttle buses near this route, you need to be extra vigilant, especially around these bus stops and around turns and intersections."

Baker acknowledged it's going to be a hard month for commuters.

"We get the fact that the next 30 days are going to be difficult," Baker said. "But if the T can truly deliver five years' worth of night and weekend work on the system overall, that's going to be a real benefit down the road to riders."

And, he said, some of the changes being made to accommodate shuttle buses could have a long-term benefit.

"Look, we've been pushing communities on bus lines for four or five years and we've had modest progress with additional bus lanes," Baker said. "This is a great opportunity for the city to test some additional possible routes for bus lanes, which could have real big benefit on a permanent basis down the road as well."