St. Croix River
Washington Co. · 114 mi · Class I–II
2,780CFS/ 6.39 ft
Optimal→Stable
Optimal: 500–3000 CFS · USGS #01021000
Length
Difficulty
Optimal
Avg Flow
Hist. Median
USGS Gauge
St. Croix International Waterway · Moosehorn NWR
The US-Canada border river of Downeast Maine — 114 miles of remote Class I–II paddling through boreal forest and past Moosehorn National Wildlife Refuge. One of the wildest and least-visited multi-day canoe routes in the northeastern United States.
Trip sections
Vanceboro to Loon Bay — 30 mi, upper river, Class I–II, remote boreal
Grand Falls to Calais — 40 mi, lower river, Class I, tidal influence
Outfitters
Sunrise Canoe and Kayak
St. Croix River trips and Downeast Maine outfitting
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.