Critics and boosters of a controversial mixed-use project on Miami's Watson Island found little common ground during a panel discussion on the development.

Front and center Wednesday in the event put together by Miami activist group Urban Environment League was Island Gardens, a proposed development with 221,000 square feet of retail space, 346,000 square feet of leisure space, 450 hotel rooms in two towers, 155 time-share condos, a mega-yacht marina and parking for 1,610 vehicles on waterfront land owned by the city. Preliminary work has started on the marina.

Related: We Object: Miami Beach Beefing About Miami's Watson Island Plans

Approved in 2001, Island Gardens has been recently dogged by accusations that the developer is quietly working with friendly Miami bureaucrats to increase the size of the project. Others have asked whether it's appropriate to go forward with a plan approved over 14 years ago given the two development booms South Florida has experienced since then.

The symposium meant to discuss "waterfront gridlock" addressed not just Island Gardens and its possible effect on traffic but also alternatives for improving public transportation. But the panel became a platform to criticize the proposal, pitting a lobbyist for developer Flagstone Property Group against a Miami resident who has sued the city to hinder construction. A Miami Beach city commissioner who has made pushing against the project a top priority and a former Miami mayor widely seen as pro-development rounded out the panel.

Miami Beach city commissioners discussed the project last month and ordered an independent study to assess how it would affect traffic on MacArthur Causeway, a frequently congested thoroughfare that connects downtown Miami and South Beach and the development's only access point. They also spoke about considering "legal options," widely taken to mean a possible lawsuit against Miami.

During the panel discussion, Miami Beach City Commissioner Michael Grieco eased off that suggestion when asked exactly what his city would do once the traffic survey is delivered.

"I got three calls from the city attorney before I got here," Grieco said. "I can't make any commitment, but we will do something."

By contrast Stephen Herbits, a Miami resident who has sued the city three times over the Watson Island project, made it clear he intends to extend the protracted legal battle he's engaged in, which seeks to show permits and concessions granted to the Flagstone project are improper. Much of his latest lawsuit relates to alleged violations of Florida's public records law by city officials, ostensibly as way to hide embarrassing information about the project.

Herbits said his experience suing the city had exposed him to what he called "organized, deliberate governmental deception" and said he would "continue to pursue" actions that expose the city for allegedly pushing the development forward without public scrutiny. He claimed city employees approached him anonymously to "tell me I have to win this case because I have to stop the city from behaving this way."

Marc Sarnoff, a Miami city commissioner who has been one of Island Gardens' biggest boosters, was invited to attend the panel but bowed out the day before, citing a scheduling conflict.

Panelist Brian May, a Floridian Partners lobbyist for the project, said previous litigation by Herbits had "cast a shadow on this project", which had affected its timeline.

"If you want to stop the project, write the guy a big check," he said.

Eleazar David Melendez can be reached at 305-347-6651.