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Maryland · Howard / Baltimore Co.

Patapsco River

🏔 Scenic River
Howard / Baltimore Co. · 39 mi · Class I–II
Optimal: 150–800 CFS · USGS #01589000
320 avg
47.6CFS
1.47 ft gauge height
Below Optimal
Stable
Flow data is live from USGS·Rapid classifications and CFS ranges need community verification·Know this river?
Avg flow: 320 cfsHist. median: 290 cfsUSGS #01589000
Patapsco Valley State Park · Maryland Scenic River

About

From the McKeldin Area through Baltimore Harbor, the Patapsco cuts 39 miles of Class I-II water through Howard and Baltimore counties at an average 320 CFS. The upper section above Daniels Dam runs through a forested gorge within Patapsco Valley State Park, offering the cleanest paddling and most consistent Class II drops. Below Daniels Dam, the middle section passes the old mill town of Ellicott City before the river transitions to tidal water for its final run to Baltimore Harbor. The 2018 removal of Bloede Dam — the largest dam removal in Maryland history — opened up additional miles of free-flowing water and improved fish passage throughout the system. Optimal flows run 150-800 CFS on USGS gauge 01589000, with the upper gorge section requiring higher water to clear the rock gardens effectively. A Maryland Scenic River designation protects the corridor through the state park sections, while Patapsco Valley State Park provides outfitter services for paddlers unfamiliar with the access points.

Solunar Fishing Activity
🌒
Waxing Crescent
15% illumination
Poor
Moon overhead
8:35 AM
Moonrise
1:09 PM
Moonset
4:01 AM
Moon underfoot
8:35 PM
Next full moon: May 3111 days
Outfitters
Patapsco Valley State Park
River access points and primitive camping in the Patapsco Valley
10-Year Flow Patterns
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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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