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Hells Canyon is a canyon created by the Snake River. There is no recognized geographic place called "Hells Canyon." According to a book by R.G. Bailey , titled Hells Canyon, it starts 145 km (90 miles) south of Lewiston, Idaho, and extends 64 km (40 miles) further south to a point near Oxbow, Oregon. However, some would dispute this definition.
In the 1950s the name "Hells Canyon" was borrowed from Hells Canyon Creek, which enters the river near what is now Hells Canyon Dam. According to Carrey, Conley and Barton in their book, Snake River of Hells Canyon, most of the early explorers referred to the gorge as Box Canyon or Snake River Canyon, though a few locals called it the "Grand Canyon of the Snake." The first reference to Hells Canyon appears in a 1895 edition of McCurdy's Marine History of the Pacific Northwest. In discussing the voyage of the steamboat Norma, the author writes: "She then bounded off, swinging into midstream and, like a racehorse, shot into the Hell Canyon . . .." The name was used by the Mazama Hiking Club in their 1931 bulletin. Bailey's book, Hells Canyon, was published in 1943. Senator Neuberger of Oregon used it in several publications in the 1950s.
The Hells Canyon area was once home to Shoshone and Nez Perce Native American tribes. According to the Nez Perce tribe, Coyote dug the Snake River Canyon in a day to protect the people on the west side of the river from the Seven Devils , a band of evil spirits living in the mountain range to the east. In the late nineteenth century, the military drove the Native Americans out and settlers began ranching and mining in the canyon.
Hells Canyon is one of the most imposing river gorges in the North American West. Until a million years ago, the Owyhee Mountains acted as a dam between the Snake River and its current confluence with the Columbia River, creating a vast lake in what is now southwestern Idaho. When the mountains were finally breached, the Snake roared northward, cutting a giant chasm through the volcanic rock.
Most of the older rocks we see in the canyon came from underwater volcanoes when Hells Canyon's terrains were part of an island arc in the mid-Pacific Ocean. These complex terrains glued themselves to North America about 150 million years ago as a result of tectonic plate movement. Vast areas were later covered with successive lava flows as recently as 6 million years ago. Uplifting from deep in the earth's core formed the Seven Devils and Eagle Cap Mountains, a process that continues today. The canyon itself is a result of both uplifting and erosion. One can see recent basalt flows, limestone formed on the ocean floor, ancient lavas, alluvial deposits, and the remains of primeval swamps that grew on the island surfaces.
The resulting canyon, roughly 16 km (10 miles) across, is not as dramatic as the Grand Canyon. However, when the surrounding peaks are visible from the river, the sense of depth is tremendous. The adjacent ridges average 1,700 m (5,500 ft) above the river. He Devil Mountain , tallest of the Seven Devils 2,863 m (9,393 ft) towers almost 2,440 m (8,000 ft) above the river, creating the deepest gorge in the United States. The canyon plunges 2.4 km (7,913 ft) from its summit to the mouth of Granite Creek, 10 km (6 miles) away, at 450 m (1,480 ft).
The river is as big as the landscape. Below Hells Canyon Dam, the Snake usually carries more water than the Colorado River through the Grand Canyon. Below the confluence with the Salmon River, flows average 990 m³/s (35,000 ft³/s) and often peak at three times that rate when the Salmon River is high. Further downstream, the Clearwater River and other rivers dump their flows into the Snake River, creating the Columbia River's largest tributary. (The total drainage area is approximately the size of Oregon.)
Starting at Hells Gate State Park (just outside of Lewiston, Idaho), it is 5 km (3 miles) to Asotin, Washington, 27 km (17 miles) to Buffalo Eddy, 42 km (26 miles) to the Grande Ronde River, 53 km (33 miles) to the Hells Canyon National Recreation Area boundary and the Oregon state line, 72 km (45 miles) to the Salmon River, 77 km (48 miles) to the Imnaha River, 85 km (53 miles) to Dug Bar, 116 km (72 miles) to Pittsburg Landing, 124 km (77 miles) to the Kirkwood Historic Ranch, 138 km (86 miles) to Sheep Creek Ranch, 142 km (88 miles) to Rush Creek Rapids, and 167 km (104 miles) to Hells Canyon Dam.
The Canyon: The Canyon is mostly public land, much of which is designated wilderness. The Canyon is massive, arid, and provides extremely stark, spectacular scenery. Solitude can be hard to find at peak use times; there are numerous jet boats, especially below Rush Creek. The lower river is often crowded on summer weekends. Few roads enter the Canyon, and those that do exist usually require 4-wheel drive.
Drainage Area and Average Annual Discharge: 241,000 km² (92,960 square miles) and 34 km³ (27,500,000 acre-feet).
Fishing: Fishing is good for trout, bass and catfish. Occasionally, steelhead and salmon are caught, although the fishing for these species is best described as 'fair.' Fishing for the legendary Hells Canyon white sturgeon up to 15 feet (5 m) in length is catch-and-release.
Boating Difficulty: Class III-IV. Most of the difficult rapids are at the beginning, then the pace of the trip slows considerably. The two major rapids, Wild Sheep and Granite Creek, should be treated with respect, especially at high flows. At high flows these rapids can easily flip the largest rafts. Those with kayaks and other small boats can portage these rapids. The remainder of the trip, while still offering some exciting rapids, is mostly serene. To avoid the slower water in the lower Canyon, many boaters take out at Pittsburg Landing (mile 32); roughly half of all trips end there.
Trip Length: For those traveling the river, there are variable lengths of trips one can take, depending on taste and choice of shuttles. Pittsburgh Landing is 51 km (32 miles), Heller Bar is 127 km (79 miles); both have road access. Other length trips 100 km (60 miles) to the confluence of the Salmon River, 116 km (72 miles) to Cache Creek are possible with a jet boat shuttle.
Boating Season: April - November. Since the dams were built, flows are usually highest in March and April, with the levels gradually dropping into late summer. However, releases fluctuate in order to assist salmon runs. For current information, contact the U.S. Forest Service, or you can call an Idaho Power recording that gives the release from Hells Canyon Dam: (800) 521-9102; in Idaho (800) 422-3143. Releases from Hells Canyon Dam often fluctuate widely, so camp well above river level and tie your boat securely.
Recommended Boating Levels: 140 to 1,100 m³/s (5,000 - 40,000 ft³/s). High water begins around 850 m³/s (30,000 ft³/s). Skilled boaters can run at higher levels, but the danger increases. Flows at the put-in vary from 140 m³/s (5,000 ft³/s) to over 14,000 m³/s (50,000 ft³/s) and average roughly 230 to 1000 m³/s (8,000 to 35,000 ft³/s). At mile 60, the Salmon River adds a significant volume: 14,000 m³/s (50,000 ft³/s) or more in late spring and early summer. Be warned that strong eddies occur at all flow levels.
Boats: Rafts -- Boats larger than 4.9 m (16 ft) and up at high flows; afternoon upstream winds can be a problem in the flat lower sections. Open Canoes -- Anyone, including experts, should think twice before attempting the big rapids at the start of the run; scouting is a must.
Water: The water is not fit for human consumption. The river gets warm 20 °C (70 °F) in summer.
Camping: The dams have trapped sediment and dam releases have eroded the beaches, so much of the camping is on grassy benches above the river. The Salmon River brings in large amounts of sand, beaches -- especially beaches appropriate for large parties -- reappear. There is no camping at the Hells Canyon put-in, and camping is restricted to one night at Granite and Saddle Creeks. Boaters must carry out human waste, and float boaters must show proof of approved receptical prior to launch. Campfires are prohibited year round. Because of fluctuating flows, camp high above the river.
Hiking: Several trails follow the river and climb side creeks (Granite Creek is a favorite).
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