The rezoning plan would change 1.6 miles of industrial waterfront into a seaside park and make it easier for developers to build as many as 7,000 new apartments over a 170-block area in Brooklyn.

"We have a once in a hundred-year opportunity to reclaim that waterfront and at the same time create a solution to one of our most pressing problems in this city, which is the lack of housing," Dan Doctoroff, Bloomberg's deputy mayor for economic development and rebuilding, said yesterday.

But business advocates fear the plan imperils the area's manufacturing jobs, which are mostly in light industries and crafts. According to the New York Industrial Retention Network, some 3,600 people hold manufacturing jobs in the area. Under the city's plan, 106 blocks now set aside for manufacturing would lose that status.

"We're certainly concerned about it," said Brian Coleman, CEO of the Greenpoint Manufacturing and Design Center, a non-profit industrial developer. "We believe that Greenpoint can still be a viable manufacturing area, one that provides blue collar jobs to working-class people."

The city's plan would preserve the areas' biggest factories, including the Domino Sugar plant and the Brooklyn Brewery, said Regina Myer of the Department of City Planning. The buildings that comprise the Greenpoint Manufacturing and Design Center would also remain manufacturing.

City planning chief Amanda Burden said the plan took a "fine-grained approach," aiming to preserve low building heights in much of the area.

Inland, the new rules would allow apartment buildings ranging from four to eight stories tall. It would also make conversion of industrial buildings into loft apartments easier.

But along the waterfront, the city will allow apartment towers ranging from 15 to 35 stories.

The two neighborhoods have become popular among apartment-seekers in recent years. Artists and young professionals have flocked there, attracted by cheap rents and proximity to Manhattan.

The plan also helps Doctoroff's pet project - the Olympics - providing for a beach volleyball and archery facility on the water between North 7th and North 14th Streets in Williamsburg. Most of that site is now an oil depot used by Bayside Fuel.

Doctoroff may be in for a fight over the site.

TransGas Energy holds an option to buy the 8.5-acre plot and wants to build a power plant there. A TransGas spokeswoman said the plant would create 1,000 to 1,500 temporary construction jobs and 40 full-time jobs. The Bayside depot is said to employ 12 full-time workers.

Community groups oppose the power plant, and Doctoroff said he was "hopeful" the state would not allow it there.

The project must be approved by the City Planning Commission and borough president Marty Markowitz, who yesterday called it "an important step."