Since the Fulton Fish Market, long a bedrock of city commerce and local color, moved to Hunts Point in the Bronx two years ago, one of its vacated waterfront structures has been very much on the minds of two downtown residents. The pair — a nonpracticing architect and Slow Food advocate, Robert LaValva, and a city planner, Jill Slater — is determined to see the historic Tin Building reborn as a public market offering regionally produced artisanal foods. Calling themselves New Amsterdam Public (newamsterdampublic.org), Mr. LaValva and Ms. Slater have garnered broad support from the local community board, elected officials including the president of Manhattan, Scott Stringer, and Assembly Speaker Sheldon Silver, as well as from kitchen notables such as Mario Batali and Alice Waters.

Tonight at the Space Gallery on Front Street, a block from the former fish market, New Amsterdam Public will throw a first birthday party. By next spring, it hopes to hold its first market fair at the Tin Building, which encloses almost half an acre of indoor, ground-level space and is supported by bright red columns.

Given the high-energy hum of the sustainable food movement, combined with the availability of an unused, city-owned market in the midst of a burgeoning downtown residential population, New Amsterdam Public would seem to be an idea whose time has come. Despite support for the concept, the Tin Building, as well as the adjacent New Market Building, also once used by the fishmongers, remain empty. Both buildings are controlled by the city’s Economic Development Corporation, which has yet to publicly propose any new use for the site. General Growth Properties, one of the nation’s largest real estate investment trusts, which leases much of the 38-acre South Street Seaport historic district, is likely to have a say in what becomes of the site. In 2004, Chicago-based General Growth purchased the Rouse Corporation, the Seaport developer that was granted a master lease by the city in 1981.

General Growth’s manager for the Seaport, Janell Vaughn, said, “the idea of a public market at the seaport is very exciting to us, especially given that there are many more downtown residents than before 9/11.” Ms. Vaughn did not say where the company would like the market to take root.

If New Amsterdam Public were to come to life, would it be just another Greenmarket among the dozens dotting the city? “The Greenmarket founders are on our board, but we’d be different,” Ms. Slater said. “Rather than farmers, it would be purveyors sourcing from the region’s farms who’ll be our vendors. Not all farmers can come into Manhattan on a regular schedule, but many would be happy to have someone here selling for them and having their products pooled for delivery with those of their neighbors.”

One such purveyor, according to Mr. LaValva, might be Ann Saxelby, who currently sells exclusively regional, artisanal cheeses at the Essex Street Market. “She’s out there getting to know the producers,” he said. “We’d have others like Ann who can source local fresh and dried meats, seafood, produce, flowers, even foraged food like wild mushrooms.”

In 1656, Peter Stuyvesant formalized the East River public market that had grown up around the ferry slip in the previous decade. Surprisingly, the tradition was broken only with the departure of the fish market, first enclosed by the city in 1822. Mr. LaValva and Ms. Slater first focused on the unused Battery Maritime Ferry Terminal as a site for a new public market. But they soon switched their focus to the empty fish market buildings. “We know that it will take a while to build recognition from both residents and the producers we’ll try to find,” Mr. LaValva said. “Our plan is to start by holding quarterly weekend food fairs at the site.”

New Amsterdam Public’s model is London’s wildly successful Borough Market, which was developed as a public market after wholesalers moved out.

The organization had hoped to launch its own effort next month with an oyster festival under the eaves of the Tin Building, or possibly at the adjoining New Market Building. But that event had to be dropped when Mr. LaValva discovered that serving raw shellfish requires a city license. The group’s Plan B, projected for next spring, is a dairy festival offering sales, tastings, and seminars, all having to do with milk, cheese, yogurt, and ice cream.

But the group needs permission from the site’s landlord, the Economic Development Corporation, to have the kickoff festival. In response to a query by The New York Sun, an development corporation spokeswoman, Janel Patterson, wrote: “Due to the poor conditions of the buildings, we could not consider using the buildings in this manner. New Amsterdam Public has now approached us about holding a single event in the plaza in front of the building. We are open to discussing that with them.”

Currently, the Tin Building is used for storage of construction materials, and for the equipment used daily by seaport street sweepers.

“We don’t want to become gadflies,” Mr. LaValva said. “But nobody should forget that there’s been a public market here, in one form or another,” for at least 350 years.

He added: “Our only message to New Yorkers is that if we can identify a new version that supports regional products, then let’s give it a chance to emerge. A public market in this spot is part of the identity of the city.”