Architectural rendering of Pier 55 project. Heatherwick Studio

Barry Diller’s decision to pull the plug on a $250 million deal to rehab and create a new landmark along the Manhattan waterfront has taken even the lawyers by surprise.

“Quite frankly, I’m not clear as to the real causes of his decision,” said Richard Emery, a founding partner of Emery Celli Brinckerhoff & Abady, who represented the City Club of New York, which had been opposed to the project.

Plans for the project, Pier 55—a 2.75 acre, elevated platform park—had been the subject of many rounds of litigation. In March, a federal judge vacated a permit issued by the U.S. Army Corps of Engineers. The City Club sued the U.S. Army Corps of Engineers in 2015, Matter of City Club of New York v. Hudson River Park Trust, 101068/15, claiming that Pier 55 was located within a “special aquatic site.”

“We were close to a settlement and nothing about our settlement would have affected his project,” Emery told the New York Law Journal Thursday afternoon. “Why he pulled the plug on this is somewhat of a mystery.”

Diller, the chairman of IAC/InterActive Corp., told The New York Times on Wednesday that he decided to abandon the project after costs ballooned from $35 million six years ago to more than $250 million today.

“Because of the huge escalating costs and the fact it would have been a continuing controversy over the next three years I decided it was no longer viable for us to proceed,” Diller told the Times.

Diller’s decision to abandon the project also surprised David Paget, a principal in the environmental law firm Sive, Paget & Riesel, who represents the Hudson River Park Trust, though Paget “certainly understands” Diller’s reasons.

“The benefits that would have been inestimable. They would have been shared by the local community, the city, the state and the millions of people that visit New York. That would have made this an iconic park-pier a destination,” Paget said Thursday afternoon.

“From my vantage point, there’s absolutely no reason that I could fathom that this project should have been contested,” Paget added, saying that there was no evidence that the floating park project would have caused environmental harm.

“If you want to try to defeat a project, no matter how noble, no matter how inspired, no matter the public support, you try to delay. Delay is the enemy of a project. ” Paget said.