A rendering of a proposed stadium to be shared by the Oakland Raiders and San Diego Chargers in Los Angeles. (Source: Manica Architecture)

OAKLAND (CBS SF) — The Oakland Raiders Thursday night announced plans to share a stadium in Southern California with the San Diego Chargers if both NFL teams fail to find new stadium solutions in their hometowns.

In a joint statement by the two conference rivals in the AFC West, the teams said they are looking at a stadium site in Carson in Los Angeles County while still looking at options in their respective current cities. (FULL TEXT: Raiders/Chargers Joint Statement)

“We have both been working in our home markets to find a stadium solution for many years, so far unsuccessfully,” the teams said.

“We are pursuing this stadium option in Carson for one straightforward reason: If we cannot find a permanent solution in our home markets, we have no alternative but to preserve other options to guarantee the future economic viability of our franchises,” the teams said.

Earlier Thursday, the head of an investor group trying to build a massive development at the current O.co Coliseum complex in Oakland warned that the Raiders could leave Oakland if officials in Alameda County don’t get involved in negotiations soon.

Speaking to the West Oakland Commerce Association, Floyd Kephart, the lead executive of New City Development LLC, said city of Oakland officials have been “very straightforward” in working on the Coliseum City project but he said, “We don’t have that same thing from Alameda County.”

Kephart, the chairman of the board of Renaissance Companies, a San Diego firm that advises hedge funds, private equity groups and financial institutions, said a development plan for the Coliseum site “has to be done in the next few months or the Raiders will leave.”

He said, “The Raiders are doing all they can” on the project, which includes a new football stadium for the team, and “it would be tragic if they leave.”

Kephart told the business group that Raiders owner Mark Davis called Alameda County Board of Supervisors President Scott Haggerty on Wednesday and “asked him to push this along.”

But Haggerty said he’s already talking to Davis on a weekly basis and county officials are committed to retaining all of Oakland’s pro sports teams, which are the Raiders, the A’s baseball team and the Golden State Warriors basketball team.

Alameda County’s participation is a key component for the $2 billion-plus Coliseum City project because the county and the city own about two-thirds of the 200 acres at the Coliseum site where the development is proposed.

Plans call for at least one new sports stadium at the site plus housing, retail stores, hotels and housing.

Kephart said the Coliseum City project “could be the vibrant urban center that everyone envisions and include 5,700 residential units and 475,000 square feet of retail space.

But he said the development “is hung up on the city and county coming together on land.”

About $106 million of outstanding debt remains on the current O.co Coliseum, which is used by both the Raiders and the A’s baseball team, but any deal to pay off the debt would depend on the county’s participation.

Haggerty said, “There are implications for the taxpayers” and county and city officials need to perform “due diligence” before they sign off on the project.

The Oakland City Council recently granted a 90-day extension to New City Development on its exclusive negotiating agreement with the city to develop the project.

Oakland Mayor Libby Schaaf said she is proposing that the agreement be amended to also include the county so the two government entities can work together.

“The county has got to be at the table with the city,” Schaaf said.

She said the project hasn’t moved forward “as quickly as any of us would have liked” but she understands that the county needs time to research the development proposal before it participates in the process.

The city envisions up to three new sports venues at the site: a new football stadium for the Raiders, a new baseball park for the A’s and a new arena for Warriors basketball games and other events.

But so far only the Raiders have expressed strong interest in participating in the project, while the Warriors have already announced plans to move across the Bay to San Francisco as early as 2018.

Kephart said if the A’s commit by next year to build a new baseball stadium at the Coliseum site it would be possible to build both a new football stadium and a baseball stadium at the site in the next five years.

“You could do two stadiums in five years,” he said.

Kephart also said, “There is enormous support in the community” for the Coliseum City project.

UPDATE FRIDAY, FEB. 20, 7:24 A.M.:

Oakland Mayor Libby Schaaf told KCBS that she is still opposed to using tax dollars to fund a new stadium here but says the public can support the infrastructure that goes into one.

“I know that the Raiders are in negotiation mode so I respect that they are going to be looking at other options and be talking about them in a very public way but it’s my job to stay focused on my objectives and that is to protect the public dollars, to keep all my sports teams in town and to add to the economic vitality of the Coliseum area,” she said.

FULL STATEMENT FROM RAIDERS & CHARGERS:

Thursday, February 19th, 6:55 p.m.

• We have both been working in our home markets to find a stadium solution for many years, so far unsuccessfully.

• We remain committed to continuing to work in our home markets throughout 2015 to try to find publicly acceptable solutions to the long-term stadium issue.

• We also both understand and respect the NFL’s relocation process, and we intend to adhere strictly to the relocation procedures that the League has set forth for Los Angeles.

In particular, we respect the right of the NFL’s owners to decide on all Los Angeles-related relocation issues and understand that any relocation application that is filed for Los Angeles must obtain the approval of three-fourths of the NFL’s owners.

• Both teams have kept the NFL owners’ committee on Los Angeles, and the Commissioner, fully informed about our joint efforts.

• We are pursuing this stadium option in Carson for one straightforward reason: If we cannot find a permanent solution in our home markets, we have no alternative but to preserve other options to guarantee the future economic viability of our franchises.

• In short, for the remainder of 2015, we intend to move down two tracks simultaneously:

On track one, we will continue to work in our home markets to find permanent stadium solutions that are publicly acceptable.

On track two, we will work in Carson to preserve our options, and the future economic viability of our franchises, in the event that our efforts in our local markets fail.

• Throughout this process we will respect the rules and procedures set forth by the League and defer completely to the ultimate decision of the NFL’s owners.

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