If crossing the south Grand Island bridges is part of your early morning commute, your trip is

about to get worse.

Work begins Monday night on an approximately $48 million project to replace the deck

— the road surface — on the northbound bridge, one of several road construction

projects this year.

With crews working overnight on the northbound span Sunday through Thursday, the southbound

bridge will handle two-way traffic until 6 a.m. when the north span will reopen.

When state officials say 6 a.m., they mean 6 a.m. For every minute after 6 that the bridge

remains closed, the contractor will be assessed a $1,000 penalty.

"There's quite an incentive to get it done in time," Thomas E. Pericak, Buffalo division

director of the state Thruway Authority, said at a media briefing Tuesday on Grand Island.

Work should be completed by November.

Grand Island commuters will not be the only drivers inconvenienced by road work in coming

weeks and months.

The Thruway between Hamburg and Silver Creek will see one of the largest single projects

the Thruway Authority has ever done, state officials announced Tuesday.

An estimated $100 million pavement and bridge rehabilitation project will be bid in

mid-April, Pericak said. The work will cover a 13-mile stretch of the Thruway. It is expected

to begin in June and is set for completion in 2012.

American Bridge Co. of Coraopolis, Pa., was awarded the contract for the Grand Island job.

"They will be removing a section of deck each night," Pericak explained, and replacing it

with precast panels. Each panel is 8 feet wide and 30 feet long; four panels are installed

side-by-side and bound together with quick-setting concrete.

The concrete has to reach its strength before the bridge can reopen in the morning.

"That's one thing we have to watch closely," Pericak said.

Crews will be able to work in a light rain because the concrete can be covered while it

cures, but air temperature is critical.

"That's one of the reasons [the contractor] elected not to start in mid-March — the

temperatures," Pericak said.

The old-fashioned way of replacing a bridge deck meant closing the bridge for the

construction season.

"The [Thruway] Authority decided several years ago to go with this method of construction,"

Pericak said. While more expensive, it minimizes the impact on traffic, he said.

Because of the volume of traffic using the bridges daily, "closing them really is not an

option," Pericak said.

When the northbound bridge is closed, two southbound entrance ramps — Grand Island

Boulevard and South State Parkway (Beaver Island) — also will be closed. A detour to

Whitehaven Road will be posted.

In case an emergency vehicle needs to cross the south bridge overnight, northbound traffic

will be stopped at the toll barrier on the Town of Tonawanda side, and a red light will be

activated to stop southbound traffic on the Grand Island side.

The 3,440-foot north bridge, which cost a little more than $6 million to build, opened in

1962. It underwent a major rehab in the mid-1980s but the deck wasn't replaced.

The new deck should be good for 30 years, according to Pericak.

Meanwhile, work will resume on reconstructing pavement on the Niagara Thruway, between

Ogden and Ontario streets.

That work will require closing some sections — near the International Railroad

Bridge, for example — on weekends beginning April 16.

Motorists are encouraged to sign up for TRANSalerts via the

Thruway Authority's Web site — www.nysthruway.gov — to receive e-mails about

unscheduled incidents.

News Staff Reporter Denise Jewell Gee contributed to this story.