Almost whimsically, two orange signs on the Fort Duquesne Bridge ramp toward Route 28 say "End Road Work."

Not even close.

Just down the road, a major construction project will block one lane of outbound Route 28 in Millvale for much of the next four years, posing a new hurdle for drivers who have faced more than a decade of traffic-snarling road work in the corridor.

The left lane just past the 31st Street Bridge was to be closed starting Monday night, leaving one outbound lane open to a half-mile beyond the 40th Street Bridge intersection.

Outbound single-lane traffic is scheduled to continue through 2014 as an estimated $120 million in projects transform Route 28 into a safer, faster-flowing highway.

About 60,000 vehicles use Route 28 on a typical weekday, and major delays are expected, starting this morning.

The Pennsylvania Department of Transportation has taken several steps to ease congestion. Traffic cameras have been installed, electronic message boards erected and an alternate route mapped through Lawrenceville.

"We're going to continue to monitor the work zone to see if there's anything we can tweak or change to improve the flow," spokesman Jim Struzzi said.

Drivers' best bet might be to check the feed from the traffic cameras before traveling. Four cameras are operational and can be viewed by going to www.dot.state.pa.us, clicking "PennDOT Near You" on the center of the page, then "11" on the map and the Traffic Cameras link on the right.

Later this week, the camera views will be available at www.511pa.com.

Some video disruption may occur as crews work out technical issues, Mr. Struzzi said.

PennDOT has installed an electronic message board on the facing of an overpass approaching the work zone, but it is beyond the Chestnut Street off-ramp to the 16th Street Bridge, the escape valve to the designated alternate route. By the time drivers can read it, they will be committed to traveling at least to the 31st Street Bridge.

The site was the only one meeting Federal Highway Administration standards for visibility and sight distance, Mr. Struzzi said.

The alternate route crosses the 16th Street Bridge, turns left at Liberty Avenue, left at 34th Street, right at Butler Street and left to the 40th Street Bridge. Drivers also can stay on Butler Street and cross at the Highland Park Bridge.

PennDOT has made improvements to three intersections on the alternate route -- 40th at Butler, Butler at Penn Avenue and Liberty at Ligonier Street -- including new turn lanes and new or re-timed traffic lights.

In the work zone, outbound traffic will use the right lane. Inbound traffic will be shifted away from the hillside, onto the inbound and outbound left lanes. Only a double yellow line will separate the two directions of traffic.

"People are going to have to make sure they're being careful and driving slowly through there," Mr. Struzzi said.

Two lanes will be maintained inbound during peak periods but only one lane will be open overnight after 8 p.m. Wednesday and Thursday and at other off-peak times.

Mr. Struzzi said construction-related delays were expected to start this morning, even though the heaviest volumes outbound are during the p.m. rush.

"There are a lot of people who travel outbound in the morning," he said.

When the last of the work is done in the fall of 2014, traffic will flow through new interchanges at the 31st and 40th street bridges, with no traffic signals on the highway mainline. The inbound and outbound sides will be separated by barriers rather than yellow stripes.

Turns and access at the 40th Street Bridge will not be affected at this point, but come winter, the left-exit ramp from the outbound side to the bridge will be closed, Mr. Struzzi said.

Construction will move into the 31st Street Bridge intersection in the fall of next year, causing that bridge and Rialto Street to close for nearly three years.

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