The continuation of the Commonwealth Avenue Bridge Construction Project is affecting traffic on the Massachusetts Turnpike.
On Saturday morning, the turnpike was down to one and two lanes in some spots in Boston.
Detour signs were put up overnight to alert drivers which include one lane on the eastbound side and two lanes on the west.
The changes will remain in effect for the next two weekends so work crews can demolish the Commonwealth Avenue Bridge.
In addition to the turnpike changes, the BU Bridge is also shut down from Packards Corner to Kenmore Square.
Public transportation will also be affected. Shuttle buses have replaced the Green Line B Branch on a section of Commonwealth Avenue from Babcock Street to Blandford.
Commuter Rail service on the Framingham-Worcester line is also suspended on weekends during the project between Boston landing and South Station.
"This impacts all modes of transportation, whether you're on the Green Line, whether you're going to be on a bus route," said Jonathan Gulliver, MassDOT Highway Administrator.
Gulliver said the best way to avoid the project is to avoid it altogether.
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"What we have been telling people for weeks is plan ahead. If you have the opportunity to be some place else, be some place else," Gulliver said.
On Monday morning, the turnpike will be back open to two lanes on both sides for the work week.
The entire project is scheduled to last until at least 5 a.m. on Monday, Aug. 14.