BOSTON (CBS) — MassDOT is warning Boston commuters that Monday morning’s commute could be moving very slowly.

“If everybody who normally comes in on a Monday morning commute chooses to come in their normal way, and they don’t re-mode, and they don’t convert, and they don’t change around their schedule– you can be in for a very long commute, our modeling suggests that could be as long as 90 minutes,” said Acting Highway Administrator Jonathan Gulliver.

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As of 5 a.m. Monday, the Mass Pike in Allston will have just two open lanes going east and west.

“This is a complex project, impacting people who drive, walk, bike and take transit and, while we are using accelerated construction techniques, we appreciate how travel times are longer for people who use the area and how the work has and will change people’s routines,” said said Transportation Secretary and CEO Stephanie Pollack.

Gulliver advised drivers to avoid the Mass Pike and Comm. Ave. near Boston University if possible — and if you cannot, give yourself extra time.

Buses are expected to replace the green line between the Babcock and Blandford Street stations.

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Pedestrians and bicyclists will only able to use the westbound side of Comm. Ave..

The Worcester/Framingham commuter rail will not be impacted.

Officials said the project was on time.

WBZ NewsRadio 1030’s Doug Cope reports 

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