In its suit, filed Feb. 17 in Suffolk Superior Court, the Boston-based nonprofit alleged that state environmental officials overstepped their legal authority by approving an amendment to the city’s harbor plan density restrictions, allowing for a 22-story high-rise they argue would severely limit public access to the water.

The Conservation Law Foundation, which has fiercely opposed the development, made good on its threat to sue the state to stop developer Jon Cronin’s $260 million project if it received approval from state environmental regulators. The project, proposed on the site of Cronin’s Whiskey Priest and Atlantic Beer Garden restaurants, got the green light from the state in December.

A controversial luxury condominium tower proposed for the South Boston Waterfront is facing a legal challenge by an environmental group that claims the development restricts access to the water and sets a dangerous precedent for Seaport construction.


The plan also calls for a $10 million extension of the city’s Harborwalk that would extend over the water.

The suit, which asks the court to reverse the state’s decision, names Energy and Environmental Affairs Secretary Matthew A. Beaton, Department of Environmental Protection Commissioner Martin Suuberg, and developer Cronin Holdings LLC.

The Conservation Law Foundation charged that Beaton and Suuberg failed in their duties to protect the public’s right to the waterfront and that their decision “has resulted in a public trust property being largely and illegally converted to private use and control,” according to the suit.

“Our hope is that the state will continue to carry out its responsibility to make sure that the public benefits from harbor development, as the law has required,” said Peter Shelley, senior counsel at the Conservation Law Foundation . “We hope this trend toward disregarding the public is stopped. It has become a loophole for private development to build fancy, expensive condominiums and office space. It’s just not right. And it’s against the law.”


The Conservation Law Foundation argues that the project violates state law Chapter 91, which protects the public’s interest and access to the sea and shoreline from non-water-dependent development.

An Energy and Environmental Affairs spokeswoman said in an e-mail that the agency, which also oversees the Department of Environmental Protection, does not comment on pending litigation.

In a statement, Cronin Holdings said changes to the city’s harbor plan necessitated by the large, dense project have “gone through an extensive public process,” pointing to more than 2,100 letters of support filed last summer with state environmental officials.

“CLF has been an outlier, and its opposition to the project is at odds with the way the project has been received by the public, neighbors, waterfront activists, the city of Boston, and the state,” the company said in the statement.

Cronin is proposing to build a 250-foot glass tower with 124 luxury condos and two stories of restaurant space at 150 Seaport Blvd .

City officials petitioned the state on Cronin’s behalf to amend their harbor plan in order to accommodate the project. Cronin is working on deals with neighboring property owners, including the city and the Massachusetts Port Authority, to acquire additional land that would expand the site from 10,500 square feet to about 25,000.

Cronin has sweetened the deal by offering to donate $1.5 million to the Martin Richard memorial park on Fort Point Channel; $250,000 for construction of civic space in the nearby Envoy Hotel; and offering a public waiting area in the lobby of the proposed tower with seating and free Wi-Fi.


The Conservation Law Foundation argued all the proposed public benefits are supposed to be on the site to offset the “extraordinary” private benefits of the project.

Katheleen Conti can be reached at kconti@globe.com. Follow her on Twitter @GlobeKConti.