OAKLAND (CBS SF) — The head of an investor group that’s hoping to build a massive development at the Oakland Coliseum complex that would include a new football stadium for the Oakland Raiders said Tuesday that the next six to eight weeks will be crucial in determining the project’s fate.

Floyd Kephart, the lead executive of New City Development LLC, told members of “Save Oakland Sports,” a group that wants to keep the city’s three pro sports teams in town, that, “I’m going to play this game until sometime in the first of October.”

Speaking at a breakfast meeting at a restaurant in Jack London Square, Kephart said, “I made a commitment that I won’t walk away until we see this through,” referring to the proposed development called Coliseum City.

Kephart, the chairman of the board of Renaissance Companies, a San Diego firm that advises hedge funds, private equity groups and financial institutions, submitted a detailed plan on Friday to city of Oakland and Alameda County officials who own the Coliseum site.

He said the next step in the process is up to the city and county when their legislative bodies return from their summer recesses in September.

When asked about the odds that his group’s plan will succeed, Kephart said, “They’re probably 50-50 at best at this stage.”

But he said the odds would increase to 70 to 80 percent if the city of Oakland buys out Alameda County’s share of the 120-acre site, which the county has asked the city to do.

Kephart said that’s because it would be easier for his development group to deal with one government entity than two.

Even though Kephart said the odds that the plan will succeed are only 50-50 at this point, he insisted, “It can be done despite all the people who say it can’t be done.”

Kephart said the key to the investor group’s plan is commercial development, saying it would make it economically feasible to build a new stadium for the Raiders, which is estimated to cost $900 million, as well as a new stadium for the Oakland A’s baseball team and a new arena for the Golden State Warriors basketball team.

He said he’s proposing that the city and county create an infrastructure financing district to channel the taxes from commercial development, which he estimates would be about $20 million a year.

Kephart said some of that money could pay for new sports stadiums, some could pay for affordable housing and infrastructure and some could help the investor group pay off the outstanding debt of more than $100 million at the Coliseum property.

Kephart said his group is also proposing that Oakland’s three sports teams own their own facilities, which he said would be more economically feasible than having a third party own the sites.

In addition to new sports stadiums, Kephart said he envisions 380,000 square feet of retail that would include technology-based and education-based retail stores and 3,500 housing units.

He said his group’s proposal is a long-term plan and will take at least 10 years to fully come to fruition.

But he said he knows it’s important for the plan to get traction soon because the Raiders, who already are considering moving to Los Angeles, could formally apply to the National Football League in October if Oakland doesn’t have a tangible plan by then.

The Warriors are planning to move to San Francisco in time for the 2018-19 season, but Kephart said he thinks the team would reconsider if it could own its own arena in Oakland.

Oakland City Councilman Larry Reid, who represents the East Oakland district where the Coliseum complex is located and is the chair of the board that oversees the Coliseum’s operations, said Kephart “didn’t say much” in terms of specific details in his presentation Tuesday.

Reid said he’s waiting to see what’s in the documents the investor group submitted to the city and the county.

“I’d like to see a plan that would take care of our sports franchises but wouldn’t use a lot of public money,” he said.

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