Petaluma Police are joining other area law enforcement agencies in bracing for Tuesday's opening of the Graton Resort and Casino in Rohnert Park.

The long-debated, much-anticipated casino is expected to draw a crowd tomorrow when it throws open its doors to the public, likely clogging traffic along Highway 101.

In a press release issued Monday, Petaluma Police Lt. Tim Lyons cautioned that there could be congestion on Petaluma Boulevard, Old Redwood Highway, Stony Point Road, McDowell Boulevard and Lakeville Highway. He advised that drivers give themselves extra travel time.

"The Petaluma Police Department has increased staffing to be ready for possible impacts and traffic mitigation options that may arise," he added, estimating that congestion could last for up to two weeks. The department, he said, is "working with Public Works, local highway construction contractors and the California Highway Patrol to minimize delays and improve circulation in and around Petaluma."

Petaluma is expected to get about $100,000 a year in mitigation money from the Indian tribe that runs the casino, which City Manager John Brown said in an earlier interview could help offset the costs of additional traffic enforcement.