Clarion River
The trophy river reborn: 8.5 miles of special-regulation big-brown water above Ridgway and wild-and-scenic river below.
← All stream pages · Tributary map
Current conditions
Gauge: USGS 03028500 — Clarion River at Johnsonburg, PA (primary - trophy reach). Lower river: 03029500 at Cooksburg
Reading baked into this page when it was last updated at 2026-10-14 20:45 — checking the live USGS feed now…
| Window | Reading |
|---|---|
| Too low (Johnsonburg) | Under 175 cfs |
| Low and fishable | Johnsonburg 175 - 200 cfs |
| Prime | Johnsonburg 200 - 500 cfs |
| High - edges only | Johnsonburg 500 - 800 cfs |
| Blown out | Johnsonburg over 800 cfs |
The upper river runs gin-to-tea in its rocky channel; the lower river takes color from the unregulated tributaries below Ridgway. After floods, Johnsonburg (dam-fed) clears days before Cooksburg.
Upper (regulated): often fishable 24 hours after events that blow out free-flowing creeks. Lower: 2-4 days.
How the bands were set: Working bands derived from USGS daily statistics, 10 years ending Oct 2026. Johnsonburg (03028500, drainage 204 sq mi): percentiles p10 144, p25 187, median 240, p75 468, p90 773 - a tight band because East Branch Clarion River Lake dam regulates the flow above. Cooksburg (03029500, drainage 807 sq mi) for the lower river: median 1,050, p25 497, p75 2,060, p95 4,510 cfs; lower-river working bands: under 450 too low, 800-2,100 prime for its bigger water, over 3,400 blown. Ridgway gauge 03029000 sits between them.
Gauge page: USGS monitoring location 03028500
Season playbook
Resolved from today's date — the current season is highlighted. On the live site this re-resolves in your browser.
Spring (Mar - May)
The water: Dam-steady upper river; hatch season builds to the late-May crescendo.
Fish present: Trophy browns and rainbows; mid-river smallmouth waking.
How to fish it: Nymph the trophy reach; dries at dusk as hatches stack.
Summer (Jun - Aug)
The water: The drake, then the sulphur spinners: June evenings are the river's high mass. Later summer, the upper stays coldest.
Fish present: Trout up; smallmouth mid; warmwater low.
How to fish it: Evening rises up top; float the middle at dawn.
Fall (Sep - Nov)This season
The water: Low, clear, and serious: pre-spawn browns in the special water.
Fish present: Browns coloring; fall smallmouth.
How to fish it: Streamers on the drops; October caddis dusks; handle big browns with wet hands and keep them wet.
Winter (Dec - Feb)
The water: Regulated and open at Johnsonburg when freestones are locked.
Fish present: Trophy trout.
How to fish it: Midges and tiny nymphs, midday, slow seams.
On now — hatch & forage for October
- Blue-Winged Olive — BWO dun and emerger
- Light Cahill and Slate Drake — Light Cahill, Isonychia nymph/dun
- October Caddis — Orange sedge, Stimulator
- Midges — Zebra Midge
Full calendar
| Item | Window | Size | Patterns | Notes |
|---|---|---|---|---|
| Little Black Stonefly | Feb - Mar | #14-18 | Black Stonefly nymph | Upper river riffles. |
| Blue-Winged Olive | Mar - Apr and Sep - Nov | #16-20 | BWO dun and emerger | All-season grey-day hatch. |
| Grannom caddis | Mid-Apr - early May | #14-16 | Grannom pupa and dry | The Clarion's caddis are famous - pupa drifts mornings. |
| Hendrickson, Blue Quill, March Brown | Mid-Apr - Jun | #10-16 | Hendrickson dun, Blue Quill, March Brown | The spring mayfly ladder on the trophy reach. |
| Sulphur (little dorothea and large invaria) | Mid-May - mid Jun | #16-18 and #12-14 | Sulphur dun, emerger, spinner | THE reliable evening hatch of the upper river. |
| Green Drake and Coffin Fly | Late May - mid Jun | #8-12 | Green Drake dun (day), Coffin Fly spinner (dusk) | THE CLARION'S SIGNATURE EVENT - published regional windows run about May 27 to June 14. Big duns by day on the pools, spinner falls at dark. Weather can move it a week either way. |
| Light Cahill and Slate Drake | May - Jul and Sep - Oct | #10-16 | Light Cahill, Isonychia nymph/dun | Summer evenings; slate drake again in fall. |
| Golden Stonefly | Jun - Jul | #8-12 | Golden stone nymph | Big-riffle nymphing on the middle river. |
| Terrestrials and Trico (slow pools) | Jul - Sep | #10-24 | Ants, beetles, hoppers; Trico spinners mornings | Slow trophy-reach pools at dawn. |
| October Caddis | Sep - Oct | #10-12 | Orange sedge, Stimulator | Fall dusk on the upper river. |
| Midges | Year-round | #20-26 | Zebra Midge | Winter in the regulated reach. |
Weather & conditions playbook
The row matching the live flow band is highlighted when the gauge answers.
| Condition | What changes | Tactics | Flies | Verdict |
|---|---|---|---|---|
| High and off-color | The upper river, fed by East Branch Lake, often stays fishable when everything else blows - check Johnsonburg, not the sky. | Upper reach edges; if Cooksburg is over 3,400, the lower river is a float-only or no-go. | Streamers in the regulated water. | Upper yes, lower no. |
| Prime (Johnsonburg 200 - 500) | The trophy reach at its best: full seams, hatches on schedule. | Fish the hatch hour religiously; spinners at dark in June. | Season's ladder - drake box ready in late May. | Go. |
| Low and clear (under 175) | Technical trophy water: long leaders, no shadows. | Dawn and dusk; emergers over dries. | BWO, midges, sulphur emergers in season. | Hard and rewarding. |
| Cold snap | Regulated flow keeps seams open and fish feeding at midday. | The region's best winter plan: Johnsonburg midges. | Zebra midges, tiny pheasant tails. | Go - best cold bet in this catalog. |
| Warm rain | Tributary plumes in the middle river; browns move on the drop up top. | Plumes mid-river; streamers on the upper drop. | Buggers, sculpin patterns. | Go. |
| Summer heat (tributaries over 68 F) | The main upper stem stays cold from the dam; the tribs and lower river warm. | Stay in the regulated reach; thermometer-check any tributary. | Terrestrials at dawn. | Upper river only. |
Access points
Johnsonburg - the branches meet (top of the trophy water) · Map pin
Parking: Borough access in Johnsonburg where the East and West Branches join.
The DHALO starts at the confluence: 8.48 miles of Delayed Harvest Artificial Lures Only downstream to Ridgway's Main Street Bridge, inside the All-Tackle Trophy Trout reach. Dam-influenced, cold, and the most consistent big-trout water in western Pennsylvania.
Ridgway - Main Street Bridge (bottom of the trophy reach) · Map pin
Parking: Borough parking in Ridgway; river access around the Main Street (Route 948) bridge.
Where the special water ends and the long mixed river begins. Ridgway is the supply town for the whole upper system.
Bendigo State Park (East Branch) · Map pin
Parking: State park lots on the East Branch above Johnsonburg.
East Branch water: smaller, colder, park-managed - the trophy system's headwater classroom and a good bad-weather alternative when the main stem is up.
Portland Mills, Irwin Run, and the River Road (middle river) · Map pin
Parking: Forest campsites and pull-offs along River Road below the Spring Creek confluence; Irwin Run access near the X, Y, Z rapids.
The wild-and-scenic middle: trout fading to smallmouth, famous rapids, and float-trip water. Mostly a boat game at prime flows.
Clear Creek and Cook Forest State Parks - Cooksburg · Map pin
Parking: Large state park lots at Cook Forest (River Road) and Clear Creek; Cooksburg bridge area.
The lower trout-and-bass water: big pools under the old-growth hemlocks, canoe liveries, and family water. Below here the river warms toward the Piney Reservoir warmwater fishery.
Access changes with postings and seasons — respect every sign, and confirm current PFBC regulations before fishing.
The full Clarion River deep dive — $9.99
The complete guide: access map with GPS pins, the full flow-band tactics, hatch calendar, weather playbook, regulations, and sources — a living guide, refreshed as conditions and data change, with refreshed editions free to buyers.
Not sure yet? Preview a full guide free: San Juan River sample (PDF) — a complete guide, so you can see exactly what you get.