The NFL’s San Diego Chargers want to build a $1.2 billion joint-use football stadium/convention center in lieu of a proposed $520 million expansion to the San Diego Convention Center, but the San Diego Convention Center Corp. says no thanks.

“While we appreciate the Chargers effort to build a new stadium, we will continue our current efforts to secure the California Coastal Commission’s support and work with all San Diegans to ensure the successful expansion of the San Diego Convention Center,” said Carol Wallace, president and CEO, SDCCC.

The California Coastal Commission, which has the final ruling on waterfront development, will consider the SDCC’s expansion proposal on October 9, according to reports. The SDCC is hoping for final approval on a plan to add about 400,000 square feet, including 200,000-250,000 square feet of exhibit space, 100,000 square feet of meeting space, and an 80,000-square-foot ballroom. The expansion project has been in the works since 2009.

The Chargers plan, also filed with the California Coastal Commission, would include 250,000 square feet of meeting and exhibition space as part of the stadium. It could be used in conjunction with the San Diego Convention Center, which has about 900,000 square feet of meeting and exhibition space. Chargers officials say the combined facility would be more cost-effective and environmentally sensitive.

However, the meeting space proposed by the Chargers would be several blocks away from the convention center. That’s a major sticking point for the SDCCC.

“Our clients, when interviewed about the proposed Chargers site, rejected a non-contiguous expansion as not meeting their needs and therefore, not viable to accomplish the goals of retaining current customers who are outgrowing the current facility and attracting those who have never been able to fit in the current facility,” said Wallace.

Further, a similar plan to build a combined stadium/convention center was proposed and rejected in 2011 by a mayor-appointed task force, added Wallace. Interim mayor Todd Gloria supports the SDCCC expansion plans.

“Contrary to suggestions we are trying to build a ‘big box on the bay,’ the proposed expansion is an environmentally designed expansion that provides a five-acre rooftop park and public plaza that protects view corridors, enhances public access and safety, and activates an underutilized part of San Diego’s downtown waterfront,” said Wallace.

The expansion would be funded by a hotel surcharge.