Traffic flows, mostly, but truer test awaits

The region sidestepped commuting chaos yesterday as the first post-Labor Day workday since the summer's Big Dig tunnel closures passed without the major problems some officials feared.

But transportation officials said the real test could come tomorrow , when roughly 60,000 Boston public schools students return to classes.

Scattered accidents complicated the morning and afternoon commutes yesterday and numerous commuters complained, mostly about the eastbound Massachusetts Turnpike. Although one lane of the Interstate 90 connector tunnel opened Friday night, giving direct access to Logan International Airport, the Turnpike's right lane was closed just before the tunnel entrance, forcing an odd merge that commuters said backed up the morning commute to the Allston-Brighton toll booths.

A spokesman for the Turnpike Authority said engineers would evaluate the lane configuration, which is meant to slow Pike traffic entering the single-lane connector tunnel, where the speed limit is 30 miles per hour. Before the tunnel's re- opening, motorists coming from the western suburbs had said their commutes had been trouble-free despite the closure.

For the past month, officials have been urging people to take public transit and stagger commute times. They attributed the relatively smooth flow of traffic yesterday to those warnings and to a month of preparation, as well as additional service on the commuter rail, subway, and ferries.

Daniel A. Grabauskas , general manager of the Massachusetts Bay Transportation Authority, said station managers reported volume heavier than expected on all lines, especially on the Blue Line and the C branch of the Green Line. He said the T plans to continue this heightened level of service throughout the week.

Grabauskas said he was waiting until later in the week before declaring success.

Mayor Thomas M. Menino said he was worried about tomorrow.

``It's Thursday night, that's the big issue," he said. ``You have schools opening . . . 504 school buses, at least, on the streets."

Suzanne Smalley of the Globe staff contributed to this report. Mac Daniel can be reached at mdaniel@globe.com