South Fork Boise River
🐟 TU Conservation
Elmore / Boise Co. · 65 mi · Class III–IV
—CFS/ 4178.75 ft
Loading…Optimal: 500–3000 CFS · USGS #13190000
Length
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Optimal
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Hist. Median
USGS Gauge
Boise National Forest · Trout Unlimited Conservation
The South Fork Boise is the best day-trip whitewater near Idaho"s capital — a dam-controlled release from Anderson Ranch Reservoir that provides reliable Class III–IV flows from May through September. The river cuts through a basalt canyon with consistent gradient and warm summer water temperatures that make it Idaho"s most popular intermediate kayaking run.
Trip sections
Anderson Ranch Dam to Danskin — Class III–IV, best whitewater
Danskin to Neal Bridge — Class II–III, intermediate run
Neal Bridge to Arrowrock Reservoir — Class II, mellow float
Outfitters
Idaho River Sports
South Fork Boise shuttles and gear rental
72-Hour Flow Forecast
NOAA NWPSLoading forecast...
10-Year Flow Patterns
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Data Quality
River conditions are community-verified. CFS ranges, difficulty ratings, and trip sections may not reflect every flow level or seasonal change. Always check current conditions, scout unfamiliar rapids, and paddle within your skill level. If you spot an error, use the Improve This River button at the top of the page — your local knowledge is what makes this atlas accurate.