August was the first full month of business for Rivers Casino, which opened in Des Plaines in late July.
Rivers generated $34 million worth of gambling business, but August revenues were down nearly 16 percent at Harrah's Joliet and more than 8 percent at Hollywood Casino Joliet. The biggest drop in business was at Grand Victoria Casino in Elgin, the closest casino to Des Plaines. August revenues were down 24 percent.