An already drawn-out battle over the proposed $30 million expansion of the popular Coastal Maine Botanical Gardens could be headed for court.

Last month, the Boothbay Board of Appeals voted 3-2 to rescind the gardens’ building permit for the expansion project. The board sided with a group of abutting property owners who argued that the project would forever alter the water quality in nearby Knickerbocker Lake, a secondary source of drinking water for the town.

On Monday, the gardens asked the appeals board to reconsider its November decision, but the request was not approved.

The project now appears to be in limbo.

The gardens submitted a new application for development that will be heard at the Jan. 17 planning board meeting. However, the gardens appears to be bracing for a legal battle.

In a sharply worded response to this week’s decision, the gardens accused the appeals board of refusing to consider important facts and singled out one unnamed member as “consistently intemperate, bullying and confrontational.” The gardens also alleged that board members had “ex parte communication” with the Anthonys, the family who has been leading the fight against the expansion for more than a year.

“Regrettably, the board’s confusion and unwillingness to correct their mistakes has set in motion what could be years of expensive and divisive litigation over a flawed and unconstitutional action that is a clear violation of our civil right to due process,” the response reads.

The 300-acre botanical gardens, which opened a decade ago, first announced its plans to expand in late 2015. The site, home to dozens of varieties of flora that bloom with the seasons, has become increasingly popular, in part because of its annual Gardens Aglow event.

The expansion’s first phase, which got underway this year, includes paving a significant portion of the property to improve parking and double the number of spaces to about 900, similar in size to a big-box store.

Over time, the gardens planned to build a new visitors center and a 22,000-square-foot conservatory, the largest in New England. The visitors center would be three stories and would include office space, restrooms and a lobby connecting to the gift shop.

The town’s planning board first approved the project in December 2016, despite concerns raised by neighbors and by the Boothbay Region Water District. Since then, criticism has escalated.

In July, the project was cited for multiple violations by the Maine Department of Environmental Protection. The violations, which included improperly displacing soil and filling natural wetlands, and for doing work without obtaining proper permits, were discovered during a spring site visit.

William Cullina, the gardens’ executive director, called the violations “minor” and said they did not stem from negligence, but extreme weather.

But for critics of the expansion, the violations validated their concerns about the expansion.