A group of Brooklyn residents is suing the city and state to block an effort to build soaring residential towers inside the boundaries of a planned $150 million waterfront park.

The proposed 85-acre park would stretch for more than a mile along the East River. It could contain as many as six towers and more than 1,200 apartments. Construction is scheduled to begin next year.

The lawsuit, filed yesterday, claims that the park would be the first in New York State to have housing within its borders and the only one to be obligated to pay completely for its own maintenance.

The suit also says the park plan fails to account for projected growth in the surrounding area, and that the city and state approval process was flawed.

“This is a scheme to award real estate developers and give them public land for condominium development,” a local resident who is named as a plaintiff in the lawsuit, Judith Francis, said yesterday.

Supporters of the park plan, who include the mayor, governor, borough president, and some community groups, have said that the housing is necessary to pay for the park’s upkeep, estimated at about $15 million a year.

A spokeswoman for the Empire State Development Corporation, the state agency overseeing the project, Deborah Wetzel, said: “Litigation often occurs for such projects.We are reviewing the papers and we will proceed as we usually do with such litigation.”