The Illinois River is the largest tributary of the Rogue River. Its 628,000-acre watershed is about 20% of the 3.3 million acre Rogue Basin. In 1984, Congress added 50.4 miles of the mainstem of the Illinois River, within the Rogue River-Siskiyou National Forest, to the National Wild and Scenic River System. The 29 mile Wild River Area of the Illinois—as it flows through the Kalmiopsis Wilderness—is a premier whitewater river and one of the most inaccessible wild river areas in the nation.
To protect a river
On the 30th Anniversary of the most far reaching river conservation legislation in U.S. history—the 1968 National Wild and Scenic Rivers Act—then Secretary of the Interior, Bruce Babbitt, advised us to celebrate our rivers. He also said the Act had set in motion a swirl of ideas and a new way of seeing the landscape as a watershed. It’s been decade and a half since the Secretary wrote:
“…rivers are more than scenic resources—they are ecological sentinels that mirror the health of the land around them. [The Wild and Scenic Rivers Act] taught us that to protect a river we must protect its watershed.”
More than a decade and a half later we are still learning this lesson.
River conservation in recent years has focused on removing destructive dams. Little attention has been paid to the Illinois River Basin. It’s one of the last best wild salmon and steelhead watersheds remaining on America’s West Coast. It has no dams. The genetics of its salmon and steelhead are about as pure as it gets south of British Columbia and Alaska. What the Illinois River Basin needs is conservation more than restoration.
There is a theory that the Illinois and Smith Rivers were once one until the uplift of the High Siskiyous spit the river in two. It makes sense, The Illinois is more like the Smith and Chetco Rivers than the Rogue. Like the Smith, there’s a high percentage of federal public lands in the Illinois Basin. Conservation of Smith River can serve as a model for what’s needed for the Illinois River.
A wild salmon and steelhead stronghold
Four factors make the Illinois River and its tributaries one of the most important salmon refuges on the West Coast, south of the Olympics.
- The Illinois River is entirely free flowing. There are no high dams within the watershed and none between its confluence with the Rogue River and the Pacific Ocean.
- The Illinois River’s wild salmon, steelhead and cutthroat trout populations are about as genetically pure as it gets. There’s never been a hatchery program in the basin. According to the Native Fish Society: “Hatchery origin salmon that stray into the river seem to be held up by the long canyon and the difficult Illinois River Falls, not allowing them to reproduce in the upper basin.” The same is likely true of the big lower tributaries of the Illinois, like Silver and Indigo Creeks, with their steep inner gorges and high stream power. The result is the native fish populations in the Illinois River Basin are amongst the most genetically intact in the Pacific Northwest. The Illinois Basin is the considered the anchor for wild salmon and steelhead recovery in the greater Rogue Basin.
- 81% of the river’s watershed is National Forest or BLM land (80% and 1% respectively) and a high percentage of the National Forest land is Wilderness, Inventoried Roadless Area or other special land allocations.
- The watershed’s proximity to the Pacific Ocean, many miles of relatively low gradient productive stream habitat within Wilderness or Inventoried Roadless Areas and relatively lightly populated interior valleys.
The Illinois River Basin
The Upper Illinois River Basin
The upper Illinois has four major tributaries, which meet in the Illinois River Valley to form the mainstem, which soon dives into the deep spectacular canyons of the North and South Kalmiopsis Roadless Area and the Kalmiopsis Wilderness. The upper tributaries are:
- Deer Creek – Once a highly productive tributary of the Illinois River, Deer Creek is still important for coho salmon but its watershed has been heavily logged and water withdrawal are an issue.
- Sucker Creek flow out of the Kangaroo Roadless Area and Red Buttes Wilderness. It’s watershed has been heavily logged and roaded . Large-scale placer mines also impact the mainstem of Sucker Creek.
- The East Fork Illinois River flows out of the High Siskiyou Roadless Area and Wilderness in California.
- The West Fork Illinois River flows out of California. It meets River/Rough and Ready Creek on the west side of the Illinois Valley . Most of the Rough and Ready Creek Watershed and parts of the West Fork’s Watershed flow through the South Kalmiopsis Roadless Area.
The Lower Illinois River Basin
The mainstem of the Illinois, beginning at the Rogue River-Siskiyou National Forest Boundary, forms the boundary of the North and South Kalmiopsis Roadless Areas, the Squaw Mountain Roadless Area and a largely unroaded. It enters the National Wild and Scenic Rogue River near the community of Agness. The Illinois’ wild salmon and steelhead populations are major contributors to the world class fishery of the lower Rogue River and Southwest Oregon’s Wild Rivers Coast and the large tributaries of the Wild Section of the Illinois create a cool clearwater refuge for the Rogue’s struggling summer steelhead populations. Green sturgeon are said to populate the river up to the Illinois River Falls.
Large tributaries of the lower 50.4 miles of the Illinois River (National Wild and Scenic Illinois River) include:
- Josephine Creek (27,790 acres) Watershed include parts of the South Kalmiopsis Roadless Area. Has the highest concentration of Darlingtonia fens (unique rare plant wetlands) in the nation. USDA FS Watershed Condition Class—Functioning at Risk.
- Briggs Creek (watershed included parts of the Briggs Roadless Area)
- Collier Creek (all but headwaters are in the Kalmiopsis Wilderness)
- Silver Creek (watershed includes parts of the North Kalmiopsis Roadless Area)
- Indigo Creek (watershed includes parts of the North Kalmiopsis Roadless Area)
- Lawson Creek (watershed include parts of the North Kalmiopsis Roadless Area)
There are many important smaller tributaries of the lower river, including: Sixmile Creek, Fall Creek, Rancheria Creek, Dailey Creek and Kondike Creek.
USDA Forest Service’s Watershed Condition Framework
In 2011 the Forest Service released its analysis and inventory of watersheds on National Forest land across the nation. It classified each watershed as either “functioning properly” (green on map), “functioning at risk” (yellow on map), or “impaired function” (non-shown on map). The agency also identified priority watershed for restoration (black star).
In the Illinois Basin, the Middle Sucker Creek and GrayBack Creek watersheds and the Dunn Creek Watershed have been selected as “priority watersheds.” Dunn Creek is a tributary of the East Fork Illinois River. An action plan as been developed for Middle Sucker and Grayback Creeks. For more inforamtion see the Forest Service Watershed Condition Framework website
Eighty percent of the land base in the Illinois Basin is managed by the Rogue River-Siskiyou National Forest. While the BLM lands make up a small percentage of the watershed they are important, botanically and ecologically, and include biologically rich valley floor forests and botanically rich Areas of Critical Environmental Concern and Research Natural Areas in the Illinois River Valley.
For additional information, photographs and a short video of wild salmon jumping Little Falls visit:
- Friends of the Kalmiopsis’ National Wild and Scenic Illinois River page.
- Rogue RiverKeepers’ Illinois River Sub-Basin page.
 Native Fish Society, Illinois River Stewardship.
 USDA Forest Service, 1997, West Fork Illinois River Watershed Analysis, Siskiyou National Forest, page 14.
 See USDA Forest Service’s Siskiyou National Forest Land and Resource Management Plan, Northwest Forest Plan, and individual watershed analysis and USDA Forest Service Watershed Condition Framework Interactive Maps.
 Cave Junction is the largest population center in the Illinois River Basin. As of the 2010 census, it’s population was a 1,883.