Landmark measures in the mayor’s new housing blueprint seek to make it easier for apartment house developers to build on industrial land.

Last week, the mayor announced that a new brownfields czar, Chris Ward, formerly of the Port Authority, will oversee a new loan fund for environmental evaluation and cleanup of former industrial sites. He will also help the city lobby the state to finally pass a law insulating brownfield developers from unnecessary liability.

More sweepingly, the housing plan promises to transform certain industrial areas, particularly along waterfronts, into densely populated residential neighborhoods. Long Island City, Port Morris, Jamaica and Williamsburg are among the areas where the mayor said he’s “asked our City Planning Commission to move aggressively with rezoning plans.”

The city has stated its aim is identifying industrial areas that are “underutilized.” Deputy Mayor Daniel Doctoroff says that all rezoning decisions will be made on a case-by-case basis: Planners will “go into an area and do a detailed survey of what’s there, what the trends are,” he said. “In Williamsburg, Greenpoint, there’s virtually nothing [in manufacturing] along the waterfront, but lots of thriving manufacturing upland.”

“The idea of rezoning waterfronts is the right way to go,” said David Yassky, chair of the City Council’s Select Committee on Waterfronts, just after the mayor’s speech. Yassky does, however, want one major modification: “We’re still going to need more tools, like zoning bonuses, for affordable housing development.”

But companies that operate in the targeted industrial areas say that the plan has a bigger hole: It fails to address what may happen to them. Manufacturers who remain in residential zones are vulnerable to fines for offenses like odors and illegal parking, and if they don’t own their buildings they’re also at risk of getting displaced to make way for residential development. “You have to put tools in place to address the negative impact,” said Adam Friedman, executive director of the New York Industrial Retention Network. “We still need food, people still need to move paper in and out, there still needs to be set designing going on. We need to come up with new land use tools that offer some stability.”