River Rock Casino reported stronger third-quarter revenues Monday as it seeks to refinance $200 million in overdue debt.

The tribal gaming business in Alexander Valley posted $31.3 million in sales for the quarter ended Sept. 30, up nearly 4 percent from the same period a year ago.

"Our focus on increased marketing on high-value players has been driving incremental business and increasing wagers in both slots and table games," said David Fendrick, River Rock's CEO.

The casino east of Geyserville is owned by the Dry Creek Pomo Indian tribe. River Rock reported $7.6 million in quarterly profit before distributions to the tribe, up 43 percent from last year.

River Rock defaulted on $200 million in debt that came due Nov. 1. The casino sold the senior notes to investors in 2003.

The majority of its investors have agreed not to pursue foreclosure or other legal remedies while the casino restructures its finances.

In a filing with U.S. securities regulators, River Rock said it will ask investors to exchange their old notes paying 9.75 percent interest for $200 million in new debt at 9 percent interest.

The new notes would mature in 2018. The casino expects to offer a share exchange agreement by Nov. 18 and finish the deal in December, it said.

The casino remains open during the restructuring.

River Rock reported daily winnings of $232 per slot machine in the third quarter, down $6 from last year. The casino had 1,286 slots last quarter, compared to 1,204 a year ago.

Earlier this year, River Rock closed its poker room and converted the space to penny slot machines.

So far this year, casino revenue is down about 1.4 percent from 2010, as higher gas prices curbed drive-up business, River Rock said.

Meanwhile, a proposed expansion of the casino remains on hold. In 2007, River Rock announced plans for a 267-room casino hotel, spa, restaurants, shops, entertainment venue, conference center and other attractions.

The project was shelved in 2008 when U.S. financial markets collapsed.

"We will be unable to proceed with the expansion project for the foreseeable future due to the unavailability of capital and lack of cash flows," River Rock said in a securities filing Monday.