Morning Call: June 15, 2004

As work nears an end on the new northbound Route 33 bridge over a sinkhole-prone stretch of Northampton County, transportation officials announced

Monday that the state will close and dismantle the adjacent southbound bridge.

State Transportation Secretary Allen D. Biehler said the southbound bridge, which has carried traffic in both directions since a sinkhole forced demolition of the northbound bridge five months ago, remains safe for motorists. But it will close around the Fourth of July, when the northbound bridge is scheduled to open.

The state Department of Transportation decided last week to dismantle the southbound bridge because it would be safer, easier and quicker, albeit a little more expensive, to build and anchor a new span at a cost of $3.3 million, rather than anchor the existing structure to solid rock 310 feet below the surface -- 5 feet more than the height of the Statue of Liberty.

"The southbound side is good," Biehler said in a telephone interview. "It's not at risk of falling in. But that's not to say if we don't see a risk, we will not shut it down tomorrow. It's very unusual geology in that section of Pennsylvania."

The original northbound bridge sank 6 inches on Jan. 24 after a sinkhole undermined a pier on a Bushkill Creek bank below. After failing to fill the sinkhole, PennDOT removed the bridge, and the federal government agreed to cover 90 percent of the cost.

The southbound bridge then dipped 1 inch between Jan. 25 and Feb. 26, and PennDOT engineers do not know why. Biehler said it has not moved since and is constantly monitored.

When the southbound bridge is closed, traffic will not be detoured through residential neighborhoods. Like northbound motorists now, southbound drivers will be routed a short distance over crossovers to be built over the grassy median to the passing lane of the other bridge, Biehler said.

Unlike the closure of the northbound bridge, he said, no highway exits will be affected. The north Route 191 exit, closed since February, will reopen when the north bridge is finished.

"There's some additional costs involved of about 10 percent, but the construction time will be shortened, and it provides a permanent fix to the bridge problem," state Rep. Craig Dally, R-Northampton said.

PennDOT spokesman Ron Young said the original cost estimate was $6.5 million, which included the emergency work and retrofitting the south side. He said the actual cost for the northbound bridge is $3.5 million, and the south bridge should be cheaper because the same design is being used.

Biehler said he has spoken to the U.S. Department of Transportation about covering any additional costs. If the federal government balks, he said, state dollars will be used.

A retrofitted southbound bridge would have cost $3 million and been finished by New Year's Day, Biehler said, but a new bridge will cost $3.3 million and be completed by Thanksgiving.

It was a cost and time differential that Dally and other area legislators could live with.

"I believe the costs associated with that are reasonable when you consider the nature of the problem is one of geology," said Sen. Rob Wonderling, R-24th District.

The northbound bridge, originally scheduled to open in September, is now expected to be completed by the end of the month, or July 4 at the latest, said Sen. Lisa Boscola, D-Northampton.

"I'm so used to PennDOT mostly doing patch up, doing what it takes to get traffic moving," she said. "But this goes beyond patch work."

PennDOT had originally planned to shore up the south bridge's piers by connecting them to bedrock. But, Biehler said, it would have been too dangerous for construction crews and motorists. He said a 40-foot crane would have had to be parked on the bridge to drill through the span's deck to solid rock in the creek area underneath, and the drilling could possibly cause sinkholes by disturbing the porous underground limestone.

PennDOT is building the new bridges without piers to avoid the unstable creek, which is pocked with sinkholes along the Palmer Township-Stockertown-Tatamy borders.

When both Route 33 bridges, which straddle the Bushkill in Palmer Township, were built in the early 1970s, they were not anchored into solid rock. Biehler said

PennDOT still does not know why the spans were built that way except that it was standard practice then.

Steve Esack