Around here
Around San Marcos River
Data Source: Recreation.gov Ā· Source: USGS GNIS Ā· Public land: USGS PAD-US Ā· Forest roads: USDA Forest Service MVUM Ā· BLM routes and areas: Bureau of Land Management (simplified for web display)
About this river
San Marcos River is a 62.0 mile river near Texas State Tubes in Texas. Streamflow is measured at the USGS gauge San Marcos Rv at San Marcos, TX (site 08170500). The National Hydrography Dataset places it at stream order 7. Reach geometry comes from the USGS National Hydrography Dataset.
Typical flow by month
1995 to 2026
San Marcos River typically runs highest in June, at a median 179 cfs, and lowest in September, at 147 cfs. The highest flow on record for any single day is 6,200 cfs, in 1999.
Show the numbers
| Month | Typical (cfs) | Usual range (cfs) |
|---|---|---|
| January | 161 | 112 to 222 |
| February | 157 | 114 to 241 |
| March | 158 | 114 to 235 |
| April | 160 | 114 to 223 |
| May | 172 | 122 to 224 |
| June | 179 | 115 to 231 |
| July | 172 | 109 to 222 |
| August | 153 | 105 to 207 |
| September | 147 | 103 to 214 |
| October | 150 | 108 to 202 |
| November | 175 | 105 to 227 |
| December | 163 | 104 to 229 |
Typical is the median of each monthās daily median values, and the usual range runs from the median 25th to the median 75th percentile, across about 32 years of record. Statistics published by the US Geological Survey for San Marcos Rv at San Marcos, TX (site 08170500). Conditions on any given day can fall well outside the usual range. Check the current reading before you go.
Boat access nearby
One mapped launch sits in the mapped area of San Marcos River. Ramp data comes from the USGS national boat-ramp inventory.
- River Trail ParkSan Marcos RiverPublic
Made to print
Put San Marcos River on your wall
This river section as an art print, drawn over the real terrain with its miles, plus the trails, roads and peaks around it. Pick the colors and the size, and see the finished print before you buy. From $39, shipping included.
Embed this gauge on your site
Paste this snippet anywhere, an outfitter page, a club site, a trip report, to show San Marcos River's live streamflow, water level and 7-day trend. It reads the USGS gauge directly, updates itself, and links back here.
See every free widget you can put on your site, including live conditions and a 7 day forecast.
