It's a late-summer tradition around the Yakima Valley: the annual Tieton River "flip-flop."

Every September, the Bureau of Reclamation opens Tieton Dam to release water that's been stored in Rimrock Lake all summer -- so it's nice and warm.

But the best part? The released water creates some of the best whitewater rafting you're gonna see!

It's a busy time of year for folks like Osprey Rafting Co., who come down from Leavenworth each season to offer heart-pounding, 12-mile whitewater raft trips down the river.

They'll be here again this year -- and they're offering a Killer Deal!

Starting at 8 Friday morning (Aug. 28), you can purchase their $85 trips for half off. They provide the gear (even a barbecue), you just show up ready to get wet. (Must be 10 or older, too.)

Trips start Sept. 5 and run through the month.

Here's a taste of what you're in for: