Warriors win judgment in fight over SF Mission Bay arena

Rendering released on Dec. 10, 2014 show the east aerial view of the Golden State Warriors' proposed new arena in San Francisco's Mission Bay area. The arena would seat 18,000 people, have a view deck, and include a 24,000 square foot public plaza on the southeast side and a 35,000 square foot public plaza on the Third Street side. Completion is slated for the start of the 2018-19 NBA season. less Rendering released on Dec. 10, 2014 show the east aerial view of the Golden State Warriors' proposed new arena in San Francisco's Mission Bay area. The arena would seat 18,000 people, have a view deck, and ... more Photo: Images Rendered By Steelblue., Courtesy Of MANICA Architecture. Photo: Images Rendered By Steelblue., Courtesy Of MANICA Architecture. Image 1 of / 10 Caption Close Warriors win judgment in fight over SF Mission Bay arena 1 / 10 Back to Gallery

The Golden State Warriors’ push to relocate the basketball team from Oakland to San Francisco’s Mission Bay neighborhood cleared a key hurdle Monday, as a judge ruled against a group that had filed multiple lawsuits to kill the project.

On Monday, San Francisco Superior Court Judge Garrett Wong ruled that the city’s environmental review of the proposed arena was adequate, rejecting arguments it had failed to consider environmental impacts, including alternative sites for the arena.

The ruling was in favor of the city’s Commission on Community Investment and Infrastructure, which oversees the development of Mission Bay, and the project sponsor, the Warriors.

In a statement, team President Rick Welts said the ruling “brings us a huge step closer to building a new state-of-the-art sports and entertainment venue, which will add needed vitality to the Mission Bay neighborhood and serve the entire Bay Area extremely well.”

“We look forward to breaking ground soon,” he said.

Mayor Ed Lee, who has portrayed the arena as his legacy project, called the decision “an important milestone in the process of bringing the Golden State Warriors back to San Francisco and to building a state-of-the-art entertainment venue the entire San Francisco Bay Area can be proud of.” The arena is to be called the Chase Center after the team reached a naming-rights deal with JPMorgan Chase.

The ruling marks the latest milestone in a 15-month fight between the Warriors and the Mission Bay Alliance, which is funded by a group of donors to UCSF. The group had argued that the 18,500-seat arena would jam area streets with traffic, slowing down access to the UCSF Medical Center at Mission Bay, which is across the street from the proposed arena. It also says a basketball arena in Mission Bay is at odds with the cluster of life science research and health care centers that has taken root in the neighborhood.

The Mission Bay Alliance was joined in the lawsuit by Save Muni, a group that has opposed the Central Subway and other local transit modernization plans. Jennifer Wade, a parent of a UCSF patient, was also part of the lawsuit.

Osha Meserve, a land-use attorney representing the alliance, said she is “disappointed on behalf of our co-plaintiffs and the people of San Francisco.” She said that the judge was under “extreme time pressure to make a ruling.” In May 2015, Gov. Jerry Brown fast-tracked the environmental approval process for the arena under a 2011 state law meant to streamline key construction projects.

Opponents consider options

While a plaintiff typically would have 60 days to file an appeal, the fast-tracking means the Mission Bay Alliance has just five days to decide whether to challenge the ruling.

“At this point we are reviewing the ruling and weighing our options,” Meserve said. “We are still committed to ensuring the protection of Mission Bay and all the investment in biosciences, health care and innovation that has occurred there due to careful planning by prior city administrations.”

The court’s ruling stated that the “mitigations” the city laid out to alleviate arena-related traffic were “reasonable” and allow transit agencies “to respond to actual travel patterns and to provide additional services efficiently based on demand.”

Save Muni co-founder Gerry Cauthen also said he is disappointed. He called the traffic mitigation plan “feeble” and “hugely flawed,” pointed to the postgame gridlock at the Warriors’ current home, Oracle Arena in Oakland, and suggested the situation in San Francisco would be no better.

“It’s an incredible collection of cars,” he said. “Unfortunately not everyone is going to jam themselves inside of a train.”

The lawsuit was one of two legal challenges the Mission Bay Alliance filed. The other, in Alameda County, seeks to invalidate an agreement between UCSF and the Warriors. That deal called for a $10 million Mission Bay Transportation Improvement Fund, which will be dedicated to controlling the flow of traffic in the neighborhood, particularly during evening arena events.

The plan calls for deploying dozens of traffic control officers along with traffic lanes dedicated to vehicles bound for the UCSF Medical Center. In addition, should traffic jams around the hospital become a problem, the Warriors have agreed to hold no more than 12 events a year at the same time as Giants games at nearby AT&T Park.

‘Thoroughly scrutinized’

The Mission Bay Alliance argues that the UCSF chancellor overstepped his authority in reaching such an agreement without approval from University of California regents. That lawsuit remains to be decided.

City Attorney Dennis Herrera said every aspect of the Chase Center has “has been thoroughly scrutinized under the law, and it has won overwhelming support every step of the way, from all parts of San Francisco — including its neighbors.”

“I hope that the decision becomes final soon, so that the much-awaited construction of the project can begin,” he said.

It has now been four years since the Warriors proposed moving to San Francisco. Originally, the team was focused on Piers 30-32 but dropped that plan because of opposition. This year, the team said the lawsuits had forced them to delay the opening of the Chase Center by a year, to 2019.

J.K. Dineen is a San Francisco Chronicle staff writer. Email: jdineen@sfchronicle.com Twitter: @SFjkdineen