The large open archway that runs from one end of Fells Point's Recreation Pier to the other symbolizes its role as a portal between the historic community and the harbor beyond, making the ultimate civic gesture for a waterfront setting.

But as part of a $45 million plan to convert the 1914 city landmark to an upscale Aloft hotel, developers are proposing that the opening be glassed-in so the area beneath the arch - which has always been an outdoor space - can become part of the hotel's interior.

"It creates a wonderful lobby in there," said J. Joseph Clarke, a developer who is working on the conversion with H&S; Properties.

The proposal to fill in the archway has the potential to spark controversy because, while it may give the hotel more indoor space, it also would change the nature and appearance of the distinctive building that was featured for many years as a police station on the NBC TV series Homicide: Life on the Street.

It would also mean that vehicles would no longer be able to drive through the archway and onto the pier. That is raising concern from the manager of a tugboat fleet that uses the pier as the base of its operations - and has 12 years to go on its lease.

"It's not going to work for us at all," said Paul Swensen, vice president and general manager of Moran Towing of Maryland, the tugboat operator, whose 40 employees park vehicles at the end of the pier.

If the opening is glazed in, he said, "I have no access to the pier other than by foot. The concept drawing they showed me does not meet our needs at all."

In addition, Swensen said, if vehicles can no longer drive onto the pier, all deliveries to the hotel would have to come from trucks parked on Thames Street. "The traffic is going to be horrendous," he said.

Swensen's observations point out some of the issues that arise when a building constructed for one use, particularly on an urban waterfront, is redesigned to accommodate others.

Clarke said the design details are still being worked out by the architects for the hotel, Beatty Harvey and Associates. Peter Fillat Architects prepared preliminary designs.

Located at 1715 Thames St., the Rec Pier was constructed as a place to store cargo delivered by boat and later became a community center, with a second-level ballroom that evolved into a gym. During the 1990s, the city made it available for filming of the Homicide series. It has been substantially dormant since the show was canceled in 1999.

Last month, the city's Board of Estimates authorized the city to sell the Rec Pier to Clarke's group - more than five years after the housing department launched a search for developers. Clarke's proposal was selected over four others submitted in 2002. H&S; joined the team in 2006.

Plans call for 130 guest rooms to be created on the 500-foot- long pier, with the brick headhouse restored to contain many of the hotel's common areas and meeting spaces. Early plans did not include glassing-in the archway. Clarke said that concept came from developer Michael Beatty of H&S.; Now that the sale has been approved by the city, he said, the architects are moving ahead with the final design work, including addressing questions raised by the plan to fill in the archway.

Paul DeMillo, an architect with Beatty Harvey, said the idea behind filling in the archway is to make the hotel's interior more attractive. "It really is kind of a black hole," he said of the archway. "It is not a pleasant space where the opening is now."

Fells Point's Aloft hotel is the second large local hotel commission for Beatty Harvey, which is also working on the Four Seasons Hotel and Residences in Harbor East and the Legg Mason Tower that will rise next to it. Whitney Bailey Cox and Magnani is the civil and structural engineer for the Fells Point project, which involves extensive reconstruction of the pier.

Because the Rec Pier is in the Fells Point historic district, the final design must be approved by Baltimore's Commission for Historical and Architectural Preservation before construction can begin.

One member of the preservation panel, Fells Point resident and architect David Gleason, said he'll be curious to see how the architects treat the headhouse.

"That building is such a wonderful piece of architectural masonry, with its brick arch, stone columns and trim," he said. "They really make a strong composition. It's not paper-thin. For an industrial building, it's very elegant."

Gleason said he hopes the architects can retain the sense of an arched opening, perhaps by setting the glass on a separate plane inside the brick wall, rather than flush with it.

Swensen said he's hopeful that the architects can address his concerns as well.

"If they come back in two weeks with something we can live with," he said, "I'll be as happy as a clam."

ed.gunts@baltsun.com