River stage
San Marcos, Blanco River
- River level
- 6.82 ft
- Status
- Below flood stage
- 7-day change
- -0.01 ft
- Recent high
- 9.99 ft
- Recent low
- 5.97 ft
Last reported 2026-10-13 | NWS BSMT2
- 30-day change
- +0.15 ft
- Average
- 7.49 ft
- Readings
- 122
- Data span
- 122 days
- Record crest
- 43.10 ft
In brief
The Blanco River at San Marcos, TX read 6.82 ft on Oct 13, 2026, 6.18 ft below action stage. That is 0.15 ft higher than 30 days earlier.
Source: National Weather Service gauge BSMT2
River level timeline
Stage threshold profile
Highest crests on record
| Rank | Crest | Date |
|---|---|---|
| 1 | 43.10 ft | 2015-05-24 |
| 2 | 42.56 ft | 2015-10-30 |
| 3 | 24.71 ft | 2021-10-14 |
| 4 | 24.14 ft | 2019-05-09 |
| 5 | 20.53 ft | 2019-05-04 |
| 6 | 15.23 ft | 2016-09-26 |
| 7 | 13.49 ft | 2017-04-11 |
| 8 | 10.93 ft | 2017-08-27 |
Flood crests recorded at this gauge by the National Weather Service.
What happens at each level
- 13.00 ft
Overbank conditions may cut off livestock and low bridges near the river
- 18.00 ft
Roadways and low bridges along the river are flooded. Vehicles cannot pass. Livestock can be stranded.
- 24.00 ft
Lowest homes are threatened. Water beings to cut off secondary roads near the river
- 30.00 ft
Water begins to enter many homes and businesses begin to have water entering the structures. More secondary and even primary raods become impassable for vehicles
- 43.00 ft
Water is several inches deep in the Walmart and CVS parking lots and other business in the region. Water surrounds the Balnco River Lodge apartments. Water into many homes and businesses along the river between I-35, SH 80 and River road. Water over teh Hwy 80 bridge at San Marcos
Written by the local National Weather Service forecast office for this exact gauge.
Frequently asked questions
Is the Blanco River flooding at San Marcos?
No. The Blanco River at San Marcos is at 6.82 ft, 6.18 ft below action stage.
What is the flood stage at San Marcos?
The National Weather Service sets action stage 13 ft, minor flooding 18 ft, moderate flooding 24 ft and major flooding 30 ft.
What is the highest the Blanco River has been at San Marcos?
The highest crest on record is 43.1 ft, on 2015-05-24.
Is the Blanco River high or low right now at San Marcos?
At 6.82 ft it is higher than 20% of readings over the last 122 days.
Stage and flood information from the NOAA National Weather Service (gauge BSMT2); daily history from the U.S. Geological Survey (site 08171350). Last reading 2026-10-13. For flood safety decisions always follow official National Weather Service warnings.