In a city where space is so tight, the notion of rezoning any inch opens up a floodgate of opinion. So it’s no surprise that the 2,200 acres under discussion in San Francisco as part of the Eastern Neighborhoods Plan have roused enough public controversy to stall the project for a decade. Yesterday, the waiting game finally moved one step closer to an end, as the San Francisco planning commission voted to approve the scheme’s 1,373-page project document, sending it to the board of supervisors for an amendment to the city’s General Plan by 2009.

Comprised of the Central Waterfront, Potrero Hill, the Mission, and East SoMa, the area known as the Eastern neighborhoods is home to most of the city’s industrial buildings, which, along with middle-income housing, are increasingly under threat from encroaching condos and offices. After envisioning an idea to halt the floodtide of new development in the late 1990s, the planning department started outlining a formal plan in 2001, when the dot-com building boom began pricing many industrial facilities out of town.

As a solution, the areas in question—which comprise up to half of each of the Eastern neighborhoods—would be rezoned and restricted solely for industrial purposes (they currently allow for housing and office space as well as industry). But despite such restrictions, coming up with a definition of “industrial” has not been easy. The advent of the internet and computerized job tools have made industrial and non-industrial facilities look more and more alike.

“Ten years ago, a video production facility was full of stages and screens and cameras. Now they all sit at computers,” said Ken Rich, project manager at the San Francisco Planning Department who has been leading a series of Friday-afternoon meetings (that typically drag into evenings), trying to hash out ways to protect light manufacturing. “The only way to really define industrial is what it’s not: offices, residential units, stores, and institutions like schools, hospitals, etc.”

The other half of the neighborhoods’ industrial areas would be zoned for mixed use, and would allow for more public green space, increased transit, greater height restrictions, and more residential units. Housing is the lightning rod for this part of the plan. There’s a delicate balance between creating much-needed affordable units and making the land appealing to developers. The current plan outlines a number of options, including requiring that 30 to 40 percent of units are allocated to mid-income earners and dedicating 20 percent of units to low-income residents. The rest of the non-industrial neighborhoods are to remain mixed-use in an array that Rich terms “more conceptual at this point.”

Local nonprofit San Francisco Planning and Urban Research Association (SPUR), which has worked closely with the city on the project, feels that the plan is quite ambitious. “It’s extremely aggressive and pushes the boundaries of what some developers consider financially feasible,” said SPUR policy director Sarah Karlinsky. SPUR supports the middle-income option to help keep families and all classes in the city. As for one of the proposed alternatives to the plan—halting new development altogether in the areas to prevent gentrification—Karlinsky argues that it was likely to create a different set of problems: “You exacerbate gentrification because the competition over the limited units available just pushes the price through the roof,” she said.

Negotiating the plan has been challenging, but with 4,000 units now on hold in the debated areas, and housing costs continuing to outpace the earning of the city’s lower and middle classes, there are many people hoping to get going on the project early next year, hammering out details as they go.