The Iskut River, located in the northwest part of the province of British Columbia, is the largest tributary of the Stikine River, entering it about above its entry into Alaska.
From its source at Kluachon Lake the Iskut River flows south and west for about Length measured using BCGNIS coordinates, topographic maps, and Toporama to the Stikine River near the border of British Columbia and Alaska. The upper Iskut flows south through a series of lakes: Kluachon Lake, Eddontenajon Lake, Tatogga Lake, Kinaskan Lake, Natadesleen Lake, and others. The middle Iskut encompasses the area between the Little Iskut River and Forrest Kerr Creek. Below the Ningunsaw River the Iskut flows southwest through a canyon and is regulated by the Forrest Kerr Hydroelectric Project, a run-of-river hydroelectric project. The lower Iskut flows west through an increasingly braided channel.
The upper Iskut is in the Klastline Plateau, a subregion of the Stikine Plateau. The middle Iskut forms the boundary between the Stikine Plateau and the Skeena Mountains. The lower Iskut flows through the Boundary Ranges of the Coast Mountains.
The Iskut River's watershed covers , and its mean annual discharge is . The river's watershed's land cover is classified as 34.6% conifer forest, 20.1% barren, 18.2% snow/glacier, 13.4% shrubland, 10.0% herbaceous, and small amounts of other cover. The mouth of the Iskut River is located about northeast of Wrangell, Alaska, about northwest of Stewart, British Columbia, and about south of Telegraph Creek, British Columbia. The Iskut watershed is highly glaciated and is characterized by landscapes shaped by geologically recent glaciers and the Laurentide Ice Sheet as well as volcanism.
The Iskut River watershed is in the asserted traditional territory of the Tahltan First Nation and Iskut First Nation, of the Tahltan people. The lower Iskut River is also in the traditional territory of the Tlingit, specifically the Shtax'héen Ḵwáan, commonly known as the Stikine River people.
The name of the Iskut River possibly comes from a Nisga'a word meaning "stinking", otherwise of unknown origin.
Course
The upper Iskut River, defined as the portion between its source and Cascade Falls, is nearly surrounded by the Stikine River and its tributaries, including the Stikine River to the north, the Klappan River to the east, and the Klastline River to the west. Much of this region around the upper Iskut watershed is encompassed within protected areas such as Mount Edziza Provincial Park, Stikine River Provincial Park, Spatsizi Plateau Wilderness Provincial Park, and others, in a large contiguous set of protected areas known collectively as the Stikine Country Protected Areas. British Columbia Highway 37, also called the Stewart–Cassiar Highway, runs along the east side of the upper and part of the middle Iskut River.
The Iskut River originates at Kluachon Lake, near the source of the Klastline River, and about west-northwest of Mount Edziza. A number of small streams feed Kluachon Lake, such as Kluachon Creek. From Kluachon Lake the Iskut River flows south about to Eddontenajon Lake, joined along the way by Zetu Creek, flowing southwest from Zechtoo Mountain.
The settlement of Iskut, home of the Tahltan Iskut First Nation, is located on Zetu Creek, southeast of Kluachon Lake. The Iskut First Nation's main Indian reserve is "Iskut 6", located at the community of Iskut. The Iskut First Nation administers two other reserves, "Kluachon 1", located at the southern end of Kluachon Lake, and "Stikine River 7", near Telegraph Creek.
From Kluachon Lake the Iskut River flows south into Eddontenajon Lake, where it receives several tributaries such as Coyote Creek, which flows west from Ealue Lake. Eddontenajon Lake has an average depth of and a maximum depth of . The community of Eddontenajon is located near the north end of Eddontenajon Lake, near Iskut. Just south of Eddontenajon Lake the Iskut River enters Tatogga Lake, into which several streams empty, including Jackson Creek, Kimball Creek, and Todagin Creek. Todagin Creek flows through Todagin South Slope Provincial Park, as well as the Todagin Wildlife Management Area.
South of Tatogga Lake the Iskut River enters Kinaskan Lake. Kinaskan Lake has an average depth of and a maximum depth of . The Iskut exits the south end of the lake and flows into Kinaskan Lake Provincial Park, then enters Natadesleen Lake. After exiting Natadesleen Lake the Iskut River continues south. At the southern end of Kinaskan Lake Provincial Park the Iskut River tumbles down Cascade Falls, a staircase of Jurassic eroded sedimentary rocks, located about below Natadesleen Lake. Cascade Falls is an impassable upstream barrier to fish migration, blocking anadromous fish from reaching the upper Iskut watershed. Cascade Falls also marks the transition between the upper and middle Iskut River drainage basins.
Just downstream of Cascade Falls the Little Iskut River joins the Iskut River. Originating in Mount Edziza Provincial Park, the Little Iskut River is a major tributary with a watershed area of , about 5% glacier-covered. Much of the lower Little Iskut River is braided. Continuing south the Iskut is joined by Three Mile Creek, then Eastman Creek. Burrage Creek, a significant tributary, joins the Iskut from the southeast, after which the Iskut begins to flow through a constraining canyon in which it is joined by Ball Creek and Durham Creek.
The Iskut flows by Iskut River Hot Springs Provincial Park. Extremely hot water, heated by magma of the Northern Cordilleran Volcanic Province, weeps out of a rocky embankment and into the Iskut River. Most of the springs are only a few metres from the river during low flows and are submerged during high flows. South of the hot springs the Iskut River is joined by More Creek, which originates in Mount Edziza Provincial Park, then Thomas Creek and Devil Creek.
Continuing south the Iskut flows along the west side of the Bob Quinn Plateau and the community of Bob Quinn Lake, on the shore of Bob Quinn Lake. Highway 37 passes through the community of Bob Quinn Lake, which is about halfway between Meziadin Junction and Dease Lake along the highway. From Bob Quinn Lake Highway 37 leaves the Iskut River and follows the Ningunsaw River and its tributary Beaverpond Creek, then crosses a pass into the Nass River watershed, where it follows the Nass tributary, Bell-Irving River.
Near Bob Quinn Lake the Iskut is joined by one of its largest tributaries, the Ningunsaw River, flowing from the southeast. The Ningunsaw River's watershed covers an area of . The landscape is very mountainous with elevations up to . About 12% of the watershed is covered by glaciers. The lower Ningunsaw is braided and has good salmonid spawning habitats, although anadromous fish are currently unable to reach the Ningunsaw. The Ningunsaw River originates in Ningunsaw Provincial Park, and flows along the edge of Ningunsaw River Ecological Reserve, which is within the river's watershed. The historic Yukon Telegraph Trail passes through Ningunsaw Provincial Park and Ecological Reserve, then runs up the Iskut River to the vicinity of the Little Iskut River, where it leaves the Iskut, passes through the Little Iskut River watershed and through Mount Edziza Provincial Park to Telegraph Creek on the Stikine River. After the Ningunsaw confluence the Iskut River turns southwest, flowing through a braided channel and receiving the waters of Estshi Creek. The braided section comes to an end as Volcano Creek joins from the east, then Forrest Kerr Creek joins from the north.
Between Forrest Kerr Creek and Snippaker Creek the Iskut River flows through the Lower Iskut Canyon, about long, which is carved into basaltic lava flows from Iskut Canyon Cone. McLymont Creek, flowing from the north, joins the Iskut in the canyon. Snippaker Creek, flowing from the south, joins at the end of the canyon. Three hydroelectric projects have been built in the area: the Forrest Kerr Hydroelectric Project, McLymont Creek Hydroelectric Project, and Volcano Creek Hydroelectric Project, all of which began operating in 2014. The largest is the Forrest Kerr Project, which diverts a portion of the Iskut River into a tunnel leading to an underground hydroelectric powerhouse.
The Lower Iskut Canyon is a barrier to fish migration, and the Forrest Kerr Project's diversion weir at the head of the canyon is impassable to fish migration. Thus anadromous fish are blocked from the middle and upper Iskut River watershed. There are ongoing studies to assess whether modifications to the river in the canyon and to the Forrest Kerr diversion weir could allow fish migration into the middle Iskut watershed.
The canyon marks the transition from the middle reach of the Iskut River to the lower reach, in which the Iskut flows in a highly braided channel almost directly west through the Coast Mountains. Below Snippaker Creek the Iskut is joined by the Verrett River, flowing from the north, Bronson Creek, from the south, Twin River, from the north, Craig River, from the south, Zippa Creek, from the south, Hoodoo River, from the north, Inhini River, from the south, Johnson River, from the north, and Caralin Creek, from the south. Forrest Kerr Creek, McLymont Creek, the Verrett, Twin, and Hoodoo Rivers all originate from glaciers radiating from the Andrei Icefield, which lies north of the lower Iskut River and east of the lower Stikine River. The upper Craig River flows through the Craig Headwaters Protected Area. The source of the Craig River is in Alaska.
A few kilometres below Caralin Creek the Iskut River empties into the Stikine River just north of the community of Stikine, and south of Fowler, Great Glacier Provincial Park, and Choquette Hot Springs Provincial Park.
History
Most of the Iskut River watershed has been part of the Tahltan peoples homeland since prehistoric times. The lower Iskut is part of a shared transitional zone between the interior plateau Tahltan and the coastal Tlingit people. In protohistoric times the Tlingit ascended the Stikine River and its tributaries, including the lower Iskut, in large canoes during the summer to dry salmon and berries. They also visited trading camps as far inland as Telegraph Creek and the Tahltan River. In the winter the Tahltan had exclusive use of the lower Iskut and Stikine for fishing, hunting, and trapping, as far downriver as the Stikine–Iskut confluence. The fishing village of Saksina was located on the lower Iskut River near the Stikine confluence. The Tahltan traded caribou and moose hides, furs, sinew, babiche, obsidian, snowshoes, and other items to the Tlingit in exchange for fish oils, dentalia and haliotis shells, knives, axes, wooden boxes, woven baskets, Chilkat blankets, and other ceremonial items.
Trade and intermarriage linked the Tahltan and Tlingit. Socially the Tahltan were divided into two exogamous moieties or clans, Tses'Kiya (raven) and Chiyone (wolf). These were further divided into three groups, sometimes also called clans. Around 1750 Tahltan–Tlingit intermarriage gave rise to a fourth group, the Nanyiee (wolf) family or band. Most of the Iskut River's watershed was inhabited by the Tahltan Tuckclarwaydee (also called "Naskoten") band of the Chiyone (wolf) clan or moiety. The Kartchottee (raven) band of the Tses'Kiya (raven) clan occupied much of the lower Stikine and Iskut Rivers.
During the maritime fur trade era of the late 18th and early 19th centuries Tlingit–Tahltan trade intensified as the Tlingit gained local monopolies on trade with Russian, British, and American trading ships. Tlingit Chief Shakes controlled trade up the Stikine and Iskut Rivers, which largely consisted of Western goods exchanged for furs. Non-indigenous people first visited the middle and upper Iskut River watershed in 1824. In 1825 the Hudson's Bay Company (HBC) and the Russian-American Company (RAC) claimed area for trapping fur-bearing mammals.