Rohnert Park and the Federated Indians of Graton Rancheria have agreed to a new revenue-sharing deal worth $40 million more than one they signed in 2003. The agreement is intended to more fully address the impacts of the casino the tribe is now building.

Opponents of the Indian casino being built next to Rohnert Park have sued the city over its recent agreement with the tribe to widen Wilfred Avenue. The suit filed Tuesday in Sonoma County Superior Court challenges the city’s conclusion that the project is exempt from state laws requiring environmental studies. Wilfred Avenue is the northern border of the Federated Indians of Graton Rancheria reservation and provides the main access to the casino resort.

The Rohnert Park City Council acted quickly Tuesday to approve an agreement under which the Federated Indians of Graton Rancheria will pay the full cost of widening Wilfred Avenue. ‘We will be moving to expedite this project, it’s in the community’s best interest,’ Mayor Jake Mackenzie said following the 4-0 vote. Vice-Mayor Pam Stafford was absent.

The Federated Indians of Graton Rancheria will pay the full $10 million cost of widening Wilfred Avenue, the access road to the Rohnert Park casino resort they are now building, under a tentative agreement with the city and county. That would be a shift from an earlier contract between the city and the tribe that required the tribe to fund half the project, a condition of the federal government’s approval of the casino.

The tribe building a Las Vegas-style casino next to Rohnert Park is seeking $800 million in financing, according to Standard & Poor’s, which has given the tribe’s bonds a higher-risk credit rating. That’s the largest sum yet stated for the Federated Indians of Graton Rancheria project on Wilfred Avenue — one of Sonoma County’s largest-ever developments.

Foes of an Indian casino on which work has started next to Rohnert Park have challenged the legality of a 2003 revenue-sharing agreement between the city and the Federated Indians of Graton Rancheria.

Nine years after the Federated Indians of Graton Rancheria announced plans to open a casino in Sonoma County, inciting opposition and controversy, the tribe has cleared its last governmental hurdle. In a quiet milestone, the federal government Friday let an agreement between the state and the tribe, known as a compact, take effect by acting neither to reject or approve it. The compact allows the tribe to operate a Las Vegas-style casino with slot machines and banking card games.

Opponents of a proposed Las Vegas-style Indian casino adjacent to Rohnert Park, in what may be a last-ditch effort, are pressing state legislators to take note of public opinion and turn the project back.

Federal officials Tuesday released what they hope will be a final ruling on the area they would oversee in the heart of Sonoma County to protect the endangered California tiger salamander. The latest plan may wind up in court, however, as part of an ongoing fight over a proposed tribal casino in Rohnert Park. The casino site has been excluded from the salamander protection zone.

An anti-casino group is urging Gov. Jerry Brown to challenge a 2010 federal decision that turned land at Rohnert Park’s edge into a reservation for an Indian tribe that wants to build a Las Vegas-style casino resort there.