Even with a sensible shirt-dress buttoned up over it, it feels a little scandalous to board a TriMet bus in my bathing suit. And were I carrying a huge inflated inner tube? Then I’d just feel goofy. At least space wouldn’t have been an issue, because only a handful of people are on the eastbound 77 with me on this Saturday morning in mid-July.

But I don’t need to bring my own tube to float the Sandy River today. I’m riding the 77 to Troutdale’s Columbia Gorge Outlets to catch the Trout Route weekend shuttle bus, a new-this-summer project from Sasquatch Adventures and the city of Troutdale, with a grant from Travel Oregon. I booked a bus ticket ($10) and a rental tube ($9) on the spur of the moment the night before. The tube rental comes with a personal floatation device (a.k.a. a life jacket), so all I need to bring is a hat, sunblock, and a water bottle—the rental tube has a handy cupholder.

Of course, I bring some snacks, too. I get to the outlet mall with loads of time to spare and hit the farmers market that sets up on Saturdays in an empty indoor space next to the Gap store. I buy a wedge of Syrah-washed Bonneville by Daniel’s Artisan Cheese from an enthusiastic cheesemonger and some rosemary crackers from Troutdale bakery Willow and Fern for a lap picnic later. More snacks are on offer at the Sasquatch Adventures store where I check in for my shuttle, but I’m not sure I need a bag of “Sasquatch Poop” (chocolate-covered marshmallows). The store also sells sunblock, hats, and dry bags for any floaters who forgot theirs, and there are lockers for rent to stow anything you don’t want to risk losing on the river. I check in and run a card for the $200 deposit (in case I run off with the floatie), and head down a corridor past the restrooms to the pickup point behind the mall.

The tour operator also runs a $5-round-trip shuttle from the outlet mall to Multnomah Falls (dogs welcome, and they ride free) that lets people avoid the permit requirement and parking fees in the falls lot, just 15 minutes east on I-84. It’s not hard to tell who’s in line for the waterfall shuttle and who’s in line for the river float. I walk past the folks in jeans and hiking boots and join the less-covered crew, some of whom are holding tubes they brought with them. After handing out some very adjustable blue life jackets, our driver tosses my neighbors’ tubes and a pile of Sasquatch-branded neon green rings into a huge trailer cage behind our short bus, and we set off for Dabney State Recreation Area, 10 minutes south.

I would have needed $10 or an annual state parks pass to park at Dabney, so I’ve already saved a shuttle fee’s worth by not driving myself, not to mention the back-and-forth of coming back later to get a car left at the put-in. Our driver reminds us that most littering on a river float is accidental, someone kicking off a flip-flop or losing hold of a koozie and not realizing it’s floated away. Vowing not to be such an offender, I roll up my snacks in a dry bag and clip it to the float handle, then roll up my phone in a smaller one and clip it to my life jacket. My shuttle-mates and I do a final sunscreen slather on the beach at Dabney and then fall back into our floaties, yelping as our butts hit the cold water.

The Sandy is slow and shallow, and the three river miles to the pickup point at Troutdale’s Glenn Otto Park (“look for the lifeguards,” our driver instructed) takes me about three hours. A light wind keeps blowing me toward the bank, and I need to kick my way back into the current. A float novice, I thought to tie a whistle to my swimsuit in case I needed to get people’s attention, but I didn’t think to bring a paddle. A string of ducklings streaks past me, and I realize flippers might have been handy, too, though they’d be awkward in the few shallow spots where I have to carry my tube while walking over the rocks. I pass under the Stark Street Bridge, where someone has tied a rope to swing out over the water, and slowly cruise by backyards and beaches.

Road noise is steady from the Historic Columbia River Highway, which runs along this section of the Sandy, but there are stretches where the only sounds are birds and my own feet splashing. I enjoy my lap picnic (with a plastic knife, as sharp objects wouldn’t be wise on an inflated tube), remind myself to reapply sunscreen every now and then, and let myself float and spin, keeping an eye ahead to make sure I’m not heading for a rock or low-hanging branch. As I  near Glenn Ottto, I pass more people playing in the water and setting up picnics on the beach, a few of them blasting music from portable speakers. The take-out point—a busy beach with a lifeguard station just before the green bridge—is hard to miss. The shallow river narrows thanks to a large sandy expanse poking in from the east bank, and my floatie picks up speed in a very attention-getting way, making the final 20 seconds on the river the most adventuresome. As I stand up, I’m careful to snag the handle of my tube so it doesn’t keep rushing under the bridge and toward the Columbia.

Just up the trail, there’s a shuttle waiting in the parking lot at Glenn Otto. The wise move here would be to wait for the next shuttle and grab an ice cream cone or sundae at Sugarpine, just steps away. But I’m tired from the sun and all the forgot-a-paddle kicking, and ready to take the shuttle back to catch the 77 toward home. While everyone on the shuttle was dressed like me, I feel a little funny again in my bathing suit and still-wet cover-up as I board TriMet. As we approach my stop and I realize my seat might have a wet spot, I’m tempted to leave a note: “It’s not what you think!” But I didn’t bring paper and pencil in my dry bag, so the next passenger will just have to live with the mystery.