PORTLAND — Some of the largest cruise ships on the planet have docked at Portland’s deep-water berth, and soon their captains should have no reason to complain that the water isn’t deep enough.

The Board of Harbor Commissioners decided Thursday to approve a permit that will allow a contractor to dredge Ocean Gateway Pier II – the city’s so-called megaberth.

The dredging will begin immediately, so it can be finished in time for the cruise ship season, which starts in June, and prevent harm to fish that breed in the spring, said Dwight Doughty, a division manager for the Maine Department of Transportation.

Doughty appeared Thursday night before the board, which voted unanimously to approve the marine construction permit. The $280,000 project will be paid for with state funds.

“This has been a fast-tracked project,” Doughty said. “We need to be done by April 9.”

The board’s decision was the final step in a permitting process that began in September after the captain of the Caribbean Princess left the pier earlier than scheduled and rode out an astronomically low tide in deeper water. Some passengers who were left on shore had to be ferried to the cruise ship.

If the ship had remained at the berth, the Caribbean Princess, which draws 27 feet of water, could have been less than a foot from the bottom.

With the dredging, the depth of the water on the eastern section of the megaberth – the area that some captains said was too shallow — is expected to increase from 28 to 30 feet to 35 feet below mean sea level.

At a dedication ceremony for the new pier in October, Panos Manzavinos, captain of the Celebrity Summit, said the water under the pier was a bit too shallow for large ships. But he said that dredging would make the megaberth “one of the best berths on the East Coast.”

City Manager Mark Rees said Portland worked with the state this winter to ensure that the water depth at the pier is never raised as an issue.

“It will be 100 percent state-funded,” Rees said. “I think the state realizes how important this is for the state and local economies. It means a lot to the city. Now we can handle some of the largest cruise ships.”

Nicole Clegg, a spokeswoman for the city, said an economic impact study done in 2010 by the University of Maine underscores the importance of the cruise ship industry to Portland and the rest of the state.

The study showed that in 2008, more than 47,000 passengers from 31 cruise ships pumped $5.8 million to $8 million into Greater Portland’s economy.

Clegg said the number of cruise passengers visiting Portland has increased since 2002 from about 10,000 a year to more than 90,000. Last year, 65 ships carrying a record 92,000 passengers berthed in Portland.

Doughty said the harbor commissioners’ decision clears the way for the dredging to start. The project has been approved by the U.S. Army Corps of Engineers and the Maine Department of Environmental Protection.

He said Woolwich-based Reed & Reed has been hired to do the job. The contractor, which built the megaberth and the adjoining Ocean Gateway terminal, already has its equipment on the site.

The contractor will have until April 9 to finish because permits issued by the Corps of Engineers and the DEP say the project cannot harm two species of fish — sturgeon and winter flounder — that breed in the spring.

Doughty said hundreds of mature and juvenile lobsters have already been moved from the construction site by the Maine Department of Marine Resources.

About 20,000 cubic yards of sand and silt will be dredged from the bottom and moved to the deepest point of the megaberth site, where the Bath Iron Works dry dock once operated.

Doughty said that disposing of the materials at sea would have been cost-prohibitive, and that getting permits from state and federal regulators could have taken months.

Only one person spoke at Thursday’s hearing. Tom Myers, director of transportation for the city of South Portland, said he hopes the project can serve as a model for other dredging operations.

Several businesses on the South Portland side of Portland Harbor need to dredge, but have no place to dispose of the materials.

“This seems to be a reasonable approach, to find a site within the harbor for disposal in a safe and environmentally sound way,” Myers said.

Staff Writer Dennis Hoey can be contacted at 791-6365 or at:

dhoey@pressherald.com