Two environmental groups want to block a planned beach swap that will allow Seaside Heights' Casino Pier to expand and a carousel to be saved.

The lawsuit filed Friday by the American Littoral Society and New Jersey Conservation Foundation claims the rules of the state's Green Acres protection program don't permit this type of trade. The New Jersey Department of Environmental Protection removed the Green Acres label from that section of the beach in June.

The lawsuit was made public Monday.

American Littoral Society Executive Director Tim Dillinghan says in a statement, "This is the first time any of us can remember a recreational, public beach being traded away to a private developer. The Green Acres program is intended to preserve such natural resources and recreational opportunities for everyone, not to place them into the hands of private developers."

The proposed swap includes 1.36 acres of beach owned by Seaside Heights and the Dentzel/Looff carousel owned by the pier. It would allow the Storino family, which owns the pier, to expand after part of the pier fell into the ocean during Superstorm Sandy.

The swap also includes 67 acres of wetlands in Toms River and a permanent conservation easement barring future development would be placed on the property.

Representatives for Casino Pier did not wish to comment on the lawsuit.