The Graton Resort and Casino, located off of Golf course West outside Rohnert Park, will be completely open by Tuesday morning, and drivers should expect some increasing traffic as early as Monday, according to the California Highway Patrol.
Petaluma police are warning drivers to allow extra time for traffic.
Both police and the CHP plan to monitor and work to mitigate any traffic issues in the area.
The $820 million casino includes 3,000 slot and video poker machines, 144 gaming tables and an 18-table non-smoking poker room, as well as high-limit slot machines and high-stakes private table game areas.
It also includes a food court, four full-service restaurant, and an events center with seating for 750 seated guests.
There are 5,700 parking spaces outdoors or in a 5-level parking garage.
The casino has been opposed at public hearings and in court since it was first planned 10 years ago for the Sears Point area of southern Sonoma County, then after strong opposition from environmentalists, at the Rohnert Park site.