For the second time in six months, bids for the first construction contract to extend light-rail to the North Shore came in so high that they may have put the project in jeopardy.

The apparent low bid of $156.5 million was $21.5 million over engineering estimates and 10 percent over budget. To continue the work, the authority has to convince federal officials it can cover the additional costs on its own.

"It would be premature to say [the project is in jeopardy]," said Dennis Veraldi, the authority's acting chief executive officer.

The project includes boring twin tunnels under the Allegheny River and constructing 1,200 feet of cut-and-cover tunnel along the western side of PNC Park. Extending the light-rail system from Downtown to the North Shore is considered a key to continuing development between PNC Park and Heinz Field.

After the bids received in September were rejected because they were too high, authority officials deferred a proposed convention center spur and station in an effort to make the project affordable.

The Port Authority has put contingency funds in the $393 million project budget, which includes $314.5 million from the Federal Transit Administration. But it has to bid 13 additional, smaller contracts to build the 1.5-mile extension and three stations, including a new Gateway Center station, Downtown.

Mr. Veraldi said bid results were being reported to the FTA yesterday afternoon, but the federal agency's review will not necessarily be the deciding factor in whether to advance the project.

"When the bids are over budget, they [FTA] want to know how we're going to handle it ... if we have enough money for the project," he said.

The authority has 120 days to review and consider the low bid, which was submitted by North Shore Constructors, a consortium led by West Mifflin-based Trumbull Corp. and Japan-based Obayashi Corp., a global firm currently boring twin tunnels for a light-rail system in Seattle.

Six companies and joint ventures submitted bids. Although some bid on only the twin tunnels and some bid on only the North Shore portion of the project, the prices fell in the same general range.

Mr. Veraldi said project officials were well aware bids for public and private projects have been coming in higher than expected nationally.

The higher bids again were attributed to growing energy costs and worldwide demand for steel and cement, key components of civil construction. In addition, contractors face higher insurance and liability risks on tunnel work.

Henry Nutbrown, who is guiding the project as authority manager for engineering-construction, was in Texas for a family emergency yesterday and could not be reached for comment.

The authority board had hoped to approve a contract at its Feb. 24 monthly meeting. Because the bids are off target, Mr. Veraldi doesn't expect a recommendation to be ready by then.

He said bids on the remaining contracts might not come in as high because the risks to contractors and their bonding companies are lower on more conventional construction.

Of the North Shore Constructors' bid, he said engineers and consultants would examine each bid item. "Ten percent [over budget] may be acceptable," he said.

When bids for the tunnel-boring contract were opened in September, the apparent low bid of $87 million was said to be 25 percent higher than engineering estimates, although the bid was disqualified in any case for not complying with bonding requirements.

The second-lowest bid of $112.9 million also was rejected. As it turned out, it was higher than any bid submitted yesterday for the tunnel-only portion of the contract.

The Port Authority repackaged the contract to give companies more options and include the cut-and-cover tunnel, as North Shore Constructors did, in hopes of lowering the price.

The cut-and-cover tunnel is to take the light-rail line from underground to the surface, near Reedsdale Street. The contract includes building about 300 feet of retaining walls and the concrete shell of the future PNC Park station.