Illinois · Unknown Co.

Illinois River

· 273 mi · Class
Optimal: 8200–24500 CFS · USGS #05568500
16,300 avg
36,700CFS
15.17 ft gauge height
Above Optimal
↑Rising (+200 cfs/hr)(+900 in 3h)
⚡Flow data is live from USGS·Rapid classifications and CFS ranges need community verification·Know this river?
Avg flow: 16,300 cfsHist. median: 0 cfsUSGS #05568500
State

The slow-moving Illinois River, which twists 273 miles through the heart of the state before joining the Mississippi River 14 miles upstream from Alton, has shown an improved fishery since the late 1970s, and anglers have made fine catches of sauger and walleyes, white bass, channel catfish, largemouth bass and panfish from both the main stream and backwaters. Forming at the junction of the Kankakee and Des Plaines Rivers in the northeastern part of the state, the Illinois and its backwaters provide some 87,000 surface acres. There are five dams on the Illinois River besides the one on the Mis

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Data Quality

River conditions are community-verified. CFS ranges, difficulty ratings, and access points may not reflect every flow level or seasonal change. Always check current conditions, scout unfamiliar rapids, and paddle within your skill level.

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