The de Blasio administration is moving to fill in a missing piece of a planned waterfront park in Brooklyn — even as other parcels of needed real estate remain out of reach.

City officials are negotiating with Motiva Enterprises, a partnership of Shell Oil and Saudi Refining, for the purchase of several plots of land on the East River straddling Williamsburg and Greenpoint, for which the administration is prepared to spend up to $5.5 million.

A portion of the Williamsburg/Greenpoint waterfront formerly off limits (pictured here in 2010) will become part of a public park under deal currently in the works. Photo: Ryan Kuonen/Flickr

The parcels are some of the missing pieces of Bushwick Inlet Park, a 28-acre green swath in a 2005 Bloomberg administration redevelopment plan that sought to transform largely industrial areas of northwest Brooklyn into primarily residential neighborhoods.

The Department of Citywide Administrative Services, which is handling negotiations, declined to share a copy of the proposed purchase contract.

Destin Singleton, a spokesperson for Motiva, said, “I cannot provide any information as I cannot comment on speculation or rumor.”

The planned purchase of about 7.55 acres — less than two of them above ground — was announced March 27 in the City Record, the official registry of New York City government business. A public hearing on the proposed acquisition will be held May 14.

Bushwick Inlet Park has been slow to grow, largely because of difficulties in purchasing land from private owners. As The New York World reported in 2011, the Bloomberg administration committed to spend $200 million to buy other portions of the site — properties city lawyers had earlier claimed ought to have cost only $20 million.

The city Department of Parks and Recreation already owns a few of the necessary parcels and has built a soccer field, facing the Manhattan skyline between North 9th and North 10th streets.

Even with the purchase of the Motiva parcels, which are currently vacant, two other pieces of land slated for the park remain in private hands. One is the waterfront site of warehouses for CitiStorage, a records-archive facility whose clients include the City of New York.

The Greenpoint Williamsburg Waterfront Access Plan, including Bushwick Inlet Park. Courtesy New York City Department of City Planning.

Norman Brodsky, who owns the CitiStorage property, says the city has been unable to make him an acceptable purchase offer.

“I would love them to take it. I would love there to be a park,” said Brodsky. “But the city has no money. They have been negligent. They have waited too long. It has been nine years since the rezoning, and now the value went up.”

He urged the city to come up with “innovative ideas” to fulfill the Bloomberg administration’s promise of a park. One course of action could be eminent domain proceedings, in which a court would determine the appropriate compensation to property holders. Brodsky said he would accept a purchase price as established in court.

But while the city may have the legal power to act, it doesn’t appear to have the financial wherewithal. No funds appear in the city’s capital budget for purchasing additional sites for Bushwick Inlet Park.

“The problem now is that there is no money to buy the rest of the land,” said Trina McKeever,  co-chair of Friends of Bushwick Inlet Park. “Motiva is the low-hanging fruit; it is the cheapest piece of property. But its acquisition certainly shows the city’s good will.”

Still unwilling to sell at any price is the Greenpoint Monitor Museum, a group devoted to preserving the history of the Brooklyn-built U.S.S. Monitor steamship, one of the first ironclad warships deployed by the Union during the Civil War. The organization owns a one-acre waterfront site donated by Motiva in 2004 and hosts occasional events on the property. It reported $15,000 in income to the IRS in 2012.

Janice Lauletta Weinmann, president of Greenpoint Monitor Museum, says that the presence of the museum’s shoreline parcel shouldn’t be an obstacle to building a green ribbon around Bushwick Inlet.

“Nobody is fighting the park,” she said. “The park is 28 acres. Our property is only one acre. There is no reason for them to put eminent domain on us. We are not in the middle.”

In an email, a spokesperson for the city Department of Parks and Recreation suggested that the city is interested in finding a way to open the Monitor site to the public. “We would be happy to meet with the owners of the Monitor parcel to find ways to make their museum happen and still allow the public full access to the entire Bushwick Inlet waterfront,” said Parks spokesperson Nathan Arnosti.

If the city were to purchase the Monitor site, “we would hope to do so via a negotiated acquisition,” Arnosti added. Eminent domain would be a last resort, he said.

Weinmann said her group would fight any attempt at a forced takeover by the city. “Somebody’s got to,” she said.

“We’re going to say that we don’t accept it,” she continued. “They will ask us how much do we want and we are just going to tell them that we are not on sale. We are not going to give it up. We won’t give it up.”

This article has been corrected. An earlier version misspelled the Monitor Museum president’s last name.