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Alaska · Lake and Peninsula Borough

Alagnak River

Wild & Scenic🏞 National Park
Lake and Peninsula Borough · 67 mi · Class II–III
Optimal: 800–4000 CFS · USGS #15300500
34°F — Dangerous cold water — high hypothermia risk
2,200 avg
11,300CFS
11.38 ft gauge height
Flood
Falling slowly (-100 cfs/hr)(+300 in 3h)
Flow data is live from USGS·Rapid classifications and CFS ranges need community verification·Know this river?
Avg flow: 2,200 cfsHist. median: 1,980 cfsUSGS #15300500
National Wild & Scenic River (1980) · Katmai National Park and Preserve · Bristol Bay Watershed

About

Wild & Scenic since 1980, the Alagnak flows 67 miles through the Lake and Peninsula Borough from Kukaklek Lake to its confluence with the Kvichak River. At 2200 CFS average flow (optimal range 800–4000), this Bristol Bay tributary runs Class II–III through Katmai National Park and Preserve, with Big Falls marking the marquee middle section where technical drops demand precise boat handling. The upper reaches below Kukaklek Lake hold trophy rainbow trout in Class II water, while the lower river near the Kvichak confluence drops to Class I–II and becomes prime king salmon water. The Yup'ik people have fished these waters since before recorded history. Remote fly-in access through operations like Alagnak Lodge makes this a destination float for serious anglers willing to commit to Alaska's logistics and weather windows. USGS gauge 15300500 tracks conditions, though most visitors rely on outfitter expertise for timing and safety in this roadless country.

Solunar Fishing Activity
🌒
Waxing Crescent
15% illumination
Poor
Moon overhead
2:10 PM
Moonrise
4:39 PM
Moonset
11:40 AM
Moon underfoot
2:10 AM
Next full moon: May 3111 days
Outfitters
Alagnak Lodge
Multi-day float trips and fly-out fishing
10-Year Flow Patterns
See 10 years of flow patterns for this river — historical analysis is a Pro feature.Upgrade to Pro →
Your Optimal Range
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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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