BRENTWOOD, N.Y. (CBSNewYork) — It took years to get approved, but now a massive development on Long Island could be stopped by a lawsuit.

As CBS2’s Carolyn Gusoff reported, school officials in Brentwood said the Heartland Town Square will bring thousands of new children they cannot afford.

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Decades of decay at the former Pilgrim State Psychiatric Center, and now the crumbling buildings are about to be replaced with a new mini-city in the heat of Long Island.

But not everyone is welcoming the 450-acre new development. Brentwood school officials said for years, their concerns have fallen on deaf ears, and they have no choice but to sue the developer and the Islip Town Board – which recently approved Heartland Town Square.

The project that 9,000 new apartments will bring 7,000 or more new students to their already overcrowded and underfunded school district.

“We are at a max right now,” said Brentwood School District Supt. Richard Loeschner. “We have 20,000 students. We have 17 school buildings that are bursting at the seams.” 

But developer Jerry Wolkoff projects less than 2,000 students when the development is complete in 30 years.

“They’re not bringing in children. The Millennials are single. The empty nesters are finished,” Wolkoff said. “It’s an insanity. It’s an insane lawsuit. It makes no sense.”

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Wolkoff also released a statement denouncing the lawsuit.

“Although we have not been officially served with the lawsuit, I believe The Brentwood School Board should be ashamed to spend needed money, budgeted for educational purposes, on a frivolous lawsuit especially since they have been cutting programs. Heartland Town Square will provide approximately $35 million annually to the school district alone and provide over 20,000 jobs. Office, managerial, and retail jobs that these High School kids can aspire to have and will have. The Brentwood School Board’s analysis and basis for a lawsuit is totally wrong and frivolous.”

But school officials said they are constrained by the state tax cap and cannot collect what is needed for a population boom.

“We the Brentwood taxpayer will in effect be subsidizing Gerald Wolkoff,” said Joseph Fritz of Brentwood. “As Yogi Berra said, it ain’t over ’til it’s over.”

But in a struggling community plagued by gangs, some residents see the development as a windfall.

“Someone comes in and wants to put a billion dollars into this area, and 25,000 jobs – and they want to stop this?” said Michael Capuano of Citizens for a Better Islip.

So after a decade of debate, approvals in place and groundbreaking scheduled for next year, Brentwood school officials said it is not too late. They are committed to stopping the northeast’s biggest development in a generation.

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School officials said the money spent on the lawsuit is an investment and not a waste of taxpayer dollars.