For 20 years, the million-square-foot waterfront building at 360 Furman St. in Brooklyn was the Jehovah’s Witnesses’ principal shipping and distribution facility. The horizontal 1928 structure, an architectural precursor to Chelsea’s landmarked Starrett-Lehigh Building, is a rarity in vertical New York City.

Now named One Brooklyn Bridge Park, the building will be the borough’s largest-ever residential conversion, placed squarely in Brooklyn Heights — one of the city’s neighborhoods most resistant to change. After the developer, Robert Levine, acquired it for $205 million in 2004 — “it was actively pursued by every major developer in the city,” he said — he partnered with the state in its Brooklyn Bridge Park project. A 2002 memorandum of understanding between the city and the state announced an 85-acre park along 1.3 miles of waterfront, with the $15.2 million annual maintenance budget to be furnished by residential and commercial revenue. The subsequent land-use plan, adopted this past December, spread this financial responsibility among Mr. Levine’s building and four mixed-use residential towers to be built on the park’s margins.

Project for Public Spaces, a nonprofit urban planning and design organization, attacked the plan for its mix of private and public functions, calling the park “basically a huge developer-driven residential real estate project.” Mr. Levine doesn’t regret partnering with the park — OBBP will make pilot payments to the park’s maintenance in lieu of property taxes — but feels that detractors fail to distinguish between his building and the future condo properties. “This building is far better for everyone as residential than it would be retained for industrial use, with the Jehovah’s Witnesses continuing to have 125 tractor trailers in and out each day,” he said.

Mr. Levine emphasized that “being a good neighbor” was a choice, that the many concessions he voluntarily made to the community were financial sacrifices. Indeed, of the 75 feet separating OBBP from the water, 50 feet were an easement belonging to the development; Mr. Levine gave this land to the park free of charge, along with other easements dating to the era when freight trains rode directly into the warehouse.

If he hadn’t joined with the park, Mr. Levine said, “We probably would’ve built more than we did. The high-rise waterfront in Williamsburg is a perfect example. Many of our competitors in the bidding process wanted to put a tower on top of this building.” In fact, Mr. Levine “would’ve very much liked to do a glass box” with the two stories he added to the structure, but agreed to extend masonry piers instead — maintaining the existing character as per the state’s request. The development also proposed an “unheard of ” revenue-sharing program, whereby a portion of its sales proceeds will go directly to the park after a $500 million threshold is crossed.

The only significant changes to the building ‘s exterior are the topfloor setbacks, providing outdoor terraces to 28 penthouses, and the removal of exterior staircases. The developers will re-create the building’s original color; two shades of gray will be painted soon. Vince Cangelosi of Creative Design Associates led the renovation, including double-stud construction and true vented kitchens.

Forty-five of the building’s 449 units, which start at $550,000, are in contract, with another “30 or 40 contracts out,” an executive vice president of Stribling & Associates, Bruce Ehrmann, said. The brokers are still working through an initial 4,000-name waiting list, with “the highest potential buyerto-buyer ratio I’ve ever seen,” Mr. Ehrmann said. Apartments have sold throughout the structure, including to buyers of multiple units on lower floors overlooking the Brooklyn-Queens Expressway. Elizabeth Stribling, a celebrity in the real estate world, bought two penthouses on the northwest corner of the 12th floor. Brooklynites and Manhattanites have come looking in equal numbers, as well as a recent surge of internationals “looking for pied-à-terres,” Mr. Ehrmann said. Perks include a driving range and private cabanas. Occupancy is expected on the east side this fall and on the west side next spring.

An uphill walk to the subway remains a drawback. And potential buyers have questions about how taxes and mortgages will be affected, as the developer leases the land, though he owns the building.

The debate continues OBBP public-private partnership, though similar arrangements have succeeded in Bryant Park and more recently in Hudson River Park. The treasurer of the Brooklyn Bridge Park Defense Fund, whose lawsuit to stop the project was dismissed last fall, Bob Stone, said, “Anybody paying pilots instead of taxes has to become proprietary; it becomes their park.” Mr. Stone, who lives on State Street in the shadow of OBBP’s two future high-rise neighbors, felt the plans for mixed-use condos were announced “out of nowhere.”

But the director of marketing and communications of the Brooklyn Bridge Conservancy, a private not-for-profit group that has received funding from OBBP, Nancy Webster, said the current plan “will give us the most park for the least development,” and pointed out that the 8.2 acres of planned development — which include OBBP — are far less than 20% of the total parkland, the maximum figure allowed by the memorandum of understanding. Ms. Webster also said that private funds ensure the park “will be well-maintained, and not subject to the normal budget cycles we’re all familiar with.”

Mr. Levine said park construction should make its own schedule, though he casually put in a word for the fast-tracking of the more southern sections — where the community is indeed park-deprived. But he was unfazed when he heard that the Empire State Development Corporation’s plans to break ground this summer at the park’s northern end — by the Brooklyn Bridge — and work its way down. With phasing uncertain, and a completion date of 2012, OBBP residents can have no near-term expectation of a green backyard.

Another local, Dave Black of Willow Place, wants construction to get going (“Why isn’t it moving faster?”), but hates the prospect of two looming high-rises. (The other two new buildings are planned near Dumbo’s Pier 1.) Mr. Levine isn’t sold on the unbuilt towers either. “It should be explored as time goes on,” he said. “Maybe the benefits from this property and others involved with the park will suffice.” An ESDC spokesman, Errol Cockfield, admitted the state is focused for now on the parklands, and would be growing a maintenance fund from OBBP’s contribution before the money was needed. He said the specific schedule of pilots from the unbuilt projects hadn’t been determined, but that a deal with the land’s owner had been reached — and the proposed developments would eventually go forward.

Complicating matters, the state Department of Transportation has said that reconstruction of the BQE cantilevers over the park site will be necessary by 2017. The staging for that effort could involve 21 bridges and overpasses. But Mr. Cockfield maintained that the DOT has made “no commitment to reconstruction” and that highway rebuilding “won’t have any impact” on the park. According to a DOT spokesman, Adam Levine, tentative plans schedule construction to begin no earlier than 2017, after years of formulating ideas, environmental impact statements, design, and coordination with relevant interests. He said there is “a small possibility” that work would be done “on the very edge of the park.” The impact on OBBP is unclear at this point, but as the building abuts the highway, potential headaches are conceivable.

On July 4, the Neptune Foundation’s Floating Pool will open on a barge moored between Piers 4 and 5, along the site of the park. The 174-capacity pool is free to the public. The interim use Brooklyn Bridge Park Beach will also open. About 43,000 square feet of sand will accommodate two beach volleyball courts, two sand soccer areas, food concessions, and cabanas. The Brooklyn Bridge Conservancy will be programming arts events that “introduce Brooklyn to the waterfront.” Like Williamsburg’s Schaefer Landing, OBBP has also offered to subsidize a water-taxi stop immediately.

The developers of OBBP have pledged that the 70,000 square feet of commercial space will be leased for uses compatible with the park. Mr. Levine said he’d spoken with Trader Joe’s, but rumors must be put on hold, as any actual deals await final park schematics. But the developer did pledge, “There will be a supermarket for sure.”