The Portland Planning Board on Tuesday night approved the latest version of a proposed boat repair yard on the downtown waterfront, roughly a year after the owner had to shelve earlier plans to accommodate a massive expansion of the city’s shipping terminal.

By Phineas Sprague Jr.’s count, Tuesday was the third time he has had to seek major revisions to his proposal for a boatyard capable of repairing large recreational and commercial vessels. The latest plan calls for a 27,600-square-foot building – to be built alongside a recently constructed 19,000-square-foot building – on 5 acres Sprague owns at 94 West Commercial St. near Casco Bay Bridge.

Sprague said he was under the gun to receive approval for the project because his Portland Yacht Services has until Dec. 31 to vacate its current space in the old Portland Co. complex at 58 Fore St.

“Now we have to put up a building in 120 days,” Sprague said after the Planning Board approved the revisions.

The vote represents the latest turn in a years-long effort to bring new businesses to Portland’s western waterfront, an industrial area that has been underutilized in recent decades.

Sprague’s company, New Yard LLC, first received Planning Board approval for his Canal Landing boatyard in December 2012. That plan called for 42,000 square feet of building space on 22 acres, including 7 acres of boat storage and room for more than a half-dozen future buildings.

But then the Maine Department of Transportation announced plans last year to double the size of the adjacent International Marine Terminal and directly link the facility to rail lines in an effort to improve Portland’s status as a destination port.

As part of the $10 million expansion, which received Planning Board approval last month, the state used eminent domain to take 17 of Sprague’s 22 acres. Both sides described the negotiations as difficult but cooperative.

On Tuesday, Sprague said the months of delays and forced revisions to his planned boatyard were financially “brutal.” But he said he knowingly played a role in his own hardship by actively recruiting Iceland-based shipping giant Eimskip to Portland. Eimskip’s choice of Portland as its only U.S. port was a key factor in the decision to double the size of the container shipping terminal.

“I knew what an opportunity this was for Portland, so I agreed to move the boatyard,” Sprague said.

No one spoke against the Canal Landing proposal during Tuesday’s meeting. The board approved the revisions on a 5-0 vote.

Sprague said he has secured an option to purchase an adjacent 10 to 11 acres from Pan Am Railways, which he said would provide additional boat storage space that was lost when the state purchased the 17 acres for the shipping terminal expansion. New Yard LLC will also have to receive permits to build the 27,600-square-foot boat repair building, which will stand 55 feet at its apex and will feature overhead doors large enough to accommodate larger vessels.