SALMON RIVER, IDAHO, USA - Dick Hauff has run Idaho's River of No Return a hundred times and obviously returned to tell about it. In fact, he was telling us about it while lulled along in a deceptively placid way not far above the Big Mallard falls. Little did we know that our comfortable stream soon would drop off into dizzying, whitewater space.

''Usually we'd camp just above Big Mallard and spend most of the night worrying,'' recounted Hauff, who had the oars on our Warren Expedition raft. Hauff retired as supervisor of this Idaho wilderness for the U.S. Forest Service only to return to the Salmon River - the River of No Return - for a second career.

''We wouldn't sleep too well that night, mostly thinking about Big Mallard,'' he continued. ''We'd get up early the next morning and head for the rapids. Afterwards we might stop and have a little survival party on the sandbar below the falls.''

Earlier in the day, Hauff and Dave Warren, the expedition leader and director of Warren Expeditions, who was oar-handler on the second raft of our party, had landed us on a no-name sandbar for another in a long line of wilderness feasts.

We were at the midpoint of a 79-mile, six-day float through the heart of a wilderness area three times larger than the state of Rhode Island. The Salmon River slices through the vast granite mass of the Idaho batholith as a knife through a cake, exposing every strata of geologic frosting.

In the Footsteps of Louis & Clark

At just about the point where our little expedition first put oars into the River of No Return some days before, explorer William Clark in 1805 had assessed the watery fury frothing over the granite jaws, and turned back. He wrote that night in his journal: ''The water runs with great violence from one rock to the other on each side foaming & roreing (sic) thro rocks in every direction, so as to render the passage of anything impossible.''

Early in our journey, somebody asked Warren what he thought about Clark's opinion. ''I quit reading Clark's journal; it scared me.'' He said it with a wry grin.

Trappers, prospectors and settlers later mastered the river, but it was always a one-way sluice that dropped 12 feet for every bone-shaking mile. Thus the Salmon became the River of No Return, a label that entered popular culture with the 1954 movie of the same name starring Marilyn Monroe and Clark Gable.

Times have changed. Jet boats skim upriver, their numbers limited by law. But no roads worthy of the name traverse the wilderness. The mail arrives via air, on impossible airstrips.

Times have changed in other ways, too. The privations of Lewis and Clark and the early settlers notwithstanding, we were enticed by one of Dave and Thyra Warren's lodge-stay floats, which I quickly dubbed ''whitewater and white sheets.'' I should have included white-knuckles, too.

Luxury On The River

In addition to a full schedule of voyages and hikes for those who want to take the outdoor experience to the limit, the Warrens offer softer adventures that appeal to the 50-plus crowd. There are river runs tailored for seniors who want to bring along the grandkids.

We softies run the same fearsome, frothing green highway on Warren's state-of-the-art rubberized rafts, but nightly we will step ashore at wilderness lodges where bed linens, hot baths and well-appointed tables are the rule.

When our commuter plane from Boise buzzed the airport at Salmon, Idaho, to scare away the elk, we had no inkling that within a week we would be sitting between Pacific time on one bank of the river and Mountain time on the other - and we would neither know or care even what day it was. The road from the airport ends at the Salmon River Lodge, where most of the outfitters put into the bottle-green waters after a comfortable overnight.

The Lodge

At the lodge, Warren immediately went over the safety rules, which included lifejackets constantly cinched mummy-tight while on the river. ''Out there,'' he warned, ''your attitude can change from 'Wa-Hoo!' to 'Uh-Oh' in the blink of an eye.''

That night the paths of several groups crossed at the lodge and tales were exchanged. We heard about a bear swimming across the bow of a raft not far downstream from where we sat. Our white tablecloths were filled with grilled salmon, garlic bread and ''dump cake'' from Warren's recipe book.

Later that evening, as other spirits were uncapped, the legends of the river grew larger. ''Your real wakeup call tomorrow will come right after you pass Disappointment Creek when you see a thread of whitewater ahead with molars at each end,'' pronounced a river veteran. ''That's Devil's Teeth up there."

As they told it, back around the turn of the century the legendary riverman Johnny McKay set out one morning with a splitting hangover only to meet Satan coming upriver. ''McKay kicked out the Devil's front teeth and drove his barge directly betwixt the molars,'' said the present riverman as if he were reciting from an encyclopedia.

''Watch for the Devil's toe sticking out of the water on the right. When you reach that, you're clear.''

Trip Tales

Not without a mite of trepidation did we climb aboard the raft the next morning. Within 48 hours we would be leaping from the relative safety of the raft to body-surf such colorfully described river dropoffs as Whiplash, Killum, Growler and T-bone. Along the way we would hear how the self-sufficient Mountain People survived, such as Bruce Crofoot, ''who took terribly sick one winter in 1910 and got well by eating bread mold. He discovered penicillin without knowing it. It's documented!''

The documentation may have come from the same book that recounted the exploits of Johnny McKay, but we loved every minute of it. One of the most unbelievable tales came just after we had leaped into the 61-degree roller-coaster swells for 100 or so yards of body-surfing exhilaration--briefly interrupted by gasping heights of terror.

As we lay exhausted on the rubber ribs of the raft and spread our arms like cormorants to gather in as much sun as possible, Warren and Hauff lugged at the 15-foot oars to reach a narrow spit of sand amid the shore rocks.

It wasn't lunchtime, so why stop? Nobody believed Warren when he roared: ''Okay, Huck Finns. Put your toes in that little stream over there and follow it up to the hot tub.''

Reluctantly, one of the party rolled off the raft into the shallow trickle. ''Warmth! Heat!'' she screamed, and started wallowing in an attempt to pull the stream around her like an overcoat. Others scrambled toward the source. There, behind a dam that someone had thoughtfully stacked in the middle of the outback, we luxuriated in a 107-degree hot tub filled by springs that could have eminated from Hades.

We were now river veterans, as ready as Johnny McKay to kick in Satan's teeth if he disturbed us. ''Not even the greenest environmentalist - and I count myself among them - has ever complained about somebody building this dam,'' laughed Warren.

In truth, these were the cleanest riverbanks I've ever seen. The only trash we saw for 79 miles was a squashed jet-boat with its prow pointing to the heavens about 20 feet up one of the granite bluffs.

''A guy tied his boat to the dock at one of the lodges,'' said Hauff. ''That night an ice jam went out upriver. The boat ended up on that bluff and the dock is somewhere near Portland, Oregon.''

Two Highlights

Two thrills remain etched in memory -- body surfing the big green wave at Whiplash rapids and mail call at Whitewater Ranch. Warren would steer away from what he called the rock gardens - yellowish fields of stone that seemed to pass within our touch under what appeared to be a moving sheet of cellophane. When he reached a window of opportunity above a whitewater channel he would yell, ''Go!'' As with the paratrooper's ''Geronimo!'' one must, with no thought of the consequences, slide instantly off the raft into a sitting position in the river, legs aligned downstream to fend off fast-approaching boulders.

The surprising thing is that nobody noticed or remembered that the water temperature barely touched 60 degrees. The chill would come later, back on the raft, when the adrenalin had stopped pumping.

After the last mountain of water had been scaled, Warren would appear out of the spray in his rubberized lifeboat - looming like an ocean liner when you are nothing but a head barely clearing the wavelets. Hands clutched at the lifejacket.

Safety!

In contrast, the excitement of the mail call was mainly vicarious. It started in the kitchen at Whitewater Wilderness Lodge after a breakfast of apple scrapple, home-grown stewed apples, homemade plum syrup, scones and blackberry butter from berries picked over the railing of the front porch. When hostess Michel Lloyd had seated us in front of our heaping portions, she turned to the two-way radio. ''If Ray wants breakfast, it'll be in the mailbox at 10:30,'' she transmitted. ''Roger,'' the reply crackled. ''He's in the air. I'll pass the word.''

Lloyd's spouse, Brandon Lever, told us to gather any postcards we wanted to send. He led us to a forest clearing behind their wilderness eden where he placed a plate of food covered with aluminum foil in a solitary mailbox. A fairway through the pines straggled on a steep downhill slope and seemed to disappear off to the right toward the river.

''Looks like a nasty dogleg five-par to me,'' commented a golfer among our number. We saw it before we heard it. A single-engine blue Cessna 185 crossed our clearing not far above the bluejays and ducked into the shadow of the river canyon. The landing consisted of a blind turn coming in from low over the water, cornering the dogleg soon after touchdown.

Mail pilot Ray Arnold gunned his craft around into takeoff position, exchanged the mail for breakfast and ate hastily on his plane's tail surface. He had 22 similar touch-and-go mail deliveries to complete before sundown.

Be Sure to Read

• Whitewater Rafting Guide School For Tourists

Practical Information

Warren River Expeditions, Salmon, Idaho.
salmonriver@raftidaho.com or (800) 765-0421. Fax (208) 756-4495. Whitewater rafting from April through August.

Warren also offers kayak workshops and steelhead fishing.

River trips are limited to 18 persons. Reservation lists start filling by mid-March. There are commuter air links to Salmon, Idaho, from Boise and Missoula, Montana.

For an unusual bed and breakfast experience, the door is open year around at Whitewater Wilderness Lodge, HC-83, Salmon River Air Route, Cascade, Idaho 83611. Rates are $95 per person April through October and $50 the rest of the year (great snowmobile country, we hear). Access by jet boat upriver, raft downriver or, for $35, via the mail plane.

Shepp Ranch (PO Box 5446, Boise 83705) is another wilderness comfort haven near the horseshoe turn of the Salmon River at Mackey Bar. All the luxuries of an exclusive resort, including hot tubs and gourmet food. Guided hunts from Shepp Ranch start at $950 and track elk, deer, bighorn sheep, bear and cougar.

George Ridge has written a Sunday travel column for the "Arizona Daily Star" in Tucson, Ariz., for 14 years. He is a professor emeritus at the University of Arizona.