VANCOUVER — The proposed Interstate 5 bridge over the Columbia River would be too low, the Coast Guard says, a judgment that could mean adding feet to the structure’s clearance and up to $150 million to its $3.5 billion price tag.

The Coast Guard issues bridge permits, and The Columbian newspaper reported Friday that the new officer responsible for them says that 95 feet of clearance wouldn’t meet the needs of either current or future commerce.

Current commerce includes Thompson Metal Fab of Vancouver, which ships oil drilling rigs to Alaska and Asia and wants clearance of at least 125 feet.

Randall Overton, bridge administrator for the Coast Guard’s 13th District in Seattle since July, said rivers aren’t like highways, where trucks can find ways around low overpasses.

If a company like Thompson “had a project they want to bid on, and it’s too big to fit under a bridge, they couldn’t get the project,” he said.

The Coast Guard’s stand adds another worry for bridge planners who haven’t nailed down financing, have gone through major design changes and have been criticized for faulty traffic projections.

In a 2008 study, bridge planners concluded that the vast majority of vessels could make the 95-foot clearance.

“We’re a bit dismayed to get this comment from the new bridge administrator …” said project Director Nancy Boyd. “It did take us by surprise. We’ve been working with the previous administrator all along.”

She said the problem might be easily resolved by adding three to five feet to the design and offering “mitigation” to affected users. She wouldn’t elaborate on what mitigation would consist of.

The Columbian said adding height could raise other problems. On- and off-ramps would have to be extended, becoming more imposing structures. The height could cause problems with flight paths at Portland International Airport and Pearson Field in Vancouver.

“We are just trying to optimize impacts to aviation versus impacts to river navigation,” said Boyd. “There’s a small bubble of where you can put something.”

Thompson Metal Fab President John Rudi said he’s been asking since 2006 for a bridge with 125 feet of clearance so that his company of 250 to 300 employees can move big projects under the new bridge. The current structure has a lift.

“It was short-sighted of whoever said we’re going to make it 95 feet because we’re going to save some money,” Rudi said. “This is the only major navigable river in the Western United States. What you’re doing is choking commerce that you may not even know is around.”

Tom Warne, a Utah transportation consultant who led an independent review that resulted in a new bridge design, said the planners did think they had an agreement with the Coast Guard for a 95-foot clearance.

He questioned spending millions of dollars and creating a larger impact from the bridge structure for what he said is an occasional need by a private company.

“Almost everything can be dismantled (to make clearance),” he said. “It’s just a matter of wanting to and cost. Should we spend $150 million so this drill rig can go underneath the bridge unimpeded? Where’s the public good in that?”