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Texas · Hays Co.

San Marcos River

Hays Co. · 75 mi · Class I–II
Optimal: 100–400 CFS · USGS #08170500
180 avg
84.4CFS
3.85 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: 180 cfsHist. median: 162 cfsUSGS #08170500
San Marcos River Foundation · Texas Paddling Trail

About

Thirteen thousand years of continuous habitation by the Clovis People and their descendants speaks to what makes the San Marcos exceptional — a spring-fed river that flows year-round through central Texas at 180 CFS average. Rising from Spring Lake in the heart of San Marcos, the river runs crystal clear for the first three miles to Rio Vista Park, then continues through 40 miles of Hill Country to Luling. At optimal flows between 100–400 CFS, the San Marcos offers Class I–II water that stays cool even in Texas summers thanks to those constant spring inputs. The Texas Paddling Trail designation recognizes 75 miles of navigable water through Hays County, with TG Canoes providing shuttle services for the most popular sections. USGS gauge 08170500 tracks the flows, though spring-fed systems like this tend toward consistency rather than the dramatic swings of rainfall-dependent rivers.

Solunar Fishing Activity
🌒
Waxing Crescent
15% illumination
Poor
Moon overhead
10:03 AM
Moonrise
3:08 PM
Moonset
4:57 AM
Moon underfoot
10:03 PM
Next full moon: May 3111 days
Outfitters
TG Canoes
San Marcos River kayak and canoe rentals
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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