Mystic — Mystic Seaport Museum representatives offered more details Tuesday night about plans to demolish its Latitude 41 restaurant and construct a 26-room, 45-foot-tall boutique hotel and restaurant during a Stonington Planning and Zoning Commission hearing.

Although the museum presented conceptual plans for the hotel and a 6,000-square-foot, 1½-story research building and testing tank for the Global Foundation for Ocean Exploration, museum representatives stressed they were not yet seeking approval for these two projects as part of their application to make 10 other changes to their master plan, which specifies the uses allowed on the museum's campus. The hearing still was continuing late Tuesday night.

Seaport officials said their partners who would be constructing the hotel and research buildings have not yet completed the detailed drawings and specifications, and those will be the subject of a future application. Instead, Seaport officials said they were seeking to get feedback from the commission before filing a formal application.

The proposed hotel, which would be set further back from Route 27 than Latitude 41, would consist of a restaurant on the first floor, with hotel rooms on the second and third floors. A small building with a 27th guest room and a utility building would be located closer to Route 27, with a courtyard between them and the hotel.

Commission members also asked questions about the flood elevation of the hotel.

Museum landscape architect Chad Frost told the commission the restaurant-hotel would be two feet above the flood elevation of 11 feet, with the hotel rooms a floor above that. Commission member Fred Diechmann pointed out that the state Department of Energy and Environmental Protection has said it is not in favor of approving residential structures in flood zones with no water-dependent uses. He added approving a hotel at the Seaport could set a precedent for other projects, such as the controversial Smiler’s Wharf project, which had pitched a hotel.

In a letter, DEEP expressed a number of concerns about the Seaport hotel involving placing residential units in flood zones, intensification of use, preserving water-dependent uses and suggested the hotel be located on another section of the property not prone to flooding.

Museum attorney John Casey said Latitude 41 is already not a water-dependent use, docking will continue to occur behind the hotel and transient boaters, campers and students already stay overnight on the museum property. He said while the hotel would be 115 feet closer to the river, the hotel would be less likely to flood than Latitude 41 because it would have a higher elevation. As for moving the hotel to another location, Casey said most of the museum property is in a flood zone.

Jason Vincent, Stonington's planning director, pointed out that DEEP’s definition of flood requirements are different than the town’s regulations.

The museum zone where the Seaport is located allows buildings up to 35 feet tall, with an opportunity for the museum to seek approval for height of up to 45 feet.

Frost told the commission that it is clear Latitude 41 is coming to the end of its life and needs replacement. Although it is located in a historic district, he said Latitude 41 was built in the 1960s as a replica of a ship captain’s home and is not considered historic.

Commission member Shaun Mastroianni called it “a little sneaky” for the museum to come to the commission now without seeking approval.

“We’re trying to be anything but sneaky,” Casey said.

He said if the museum presented 10 benign changes to its master plan now and then in a few weeks came back with two much more substantial changes, residents would ask why the hotel and research center wasn’t mentioned during a hearing on less substantial changes. He added Seaport officials already have met with neighbors. Parking would be located across the street in the museum’s north lot with valet service in the courtyard. Access would be through an existing easement Latitude 41 uses now on the Mystic River Boathouse Park property.

Deichmann questioned how people carrying boats to the boathouse park would interact with vehicles accessing the hotel, calling it a “recipe for disaster.”

Commission member Lynn Conway requested the museum show what the hotel would look like from all sides when it submits its formal application.

The application also calls for signage updates with a net reduction in square footage of signs, with the decrease reserved for future use; an expansion of the Galley restaurant; a temporary relocation of the tent now used for the Mayflower restoration project to an area behind the Rossie Mill for artifact storage during construction; a handicap ramp for the Clift Block building; a 336-square-foot Catboat Shed expansion for exhibit space and boat-building classes; demolition of the gazebo due to safety issues; the previous sale of 41 Greenmanville Ave. to a private owner; the addition of solar panels on the roof of the Rossie Mill, which will not be visible from the street; relocation of north and south restrooms, with the north restrooms demolished and incorporated into the new hotel building. The south bathrooms will be relocated and reconstructed to be more usable to visitors.

j.wojtas@theday.com