The month of September Yakima Valley’s Tieton River will transform from a lazy river into Class III rapids due to the annual Flip Flop. Throughout the month of September, the Bureau of Reclamation releases irrigation water from the Rimrock Reservoir to assist the local salmon population during spawning. The result creates an average drop on the Tieton of 55 feet per mile, while most rivers drop at an average of 20 to 30 feet per mile. The biggest and best Fall rafting can be found on the Tieton River.  Osprey Rafting has your Tieton river trips and packages!  Our trips run seven days a week and include all gear, guides, shuttling and a bbq meal!  Experience a whitewater rafting trip to remember!  Call us today to find out pricing and packaging options or to book your reservation!  1-800-743-6269