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SwedenBlanco River at San Marcos water level
River gauge, Blanco River, Texas, United States
Right now
Below flood stage
Water level
- Flow
- 0.0 cfs
History
What this means
The gauge at Blanco River at San Marcos reads 7.43 ft, a normal level.
It is 10.57 ft below the flood stage of 18.00 ft.
The level is falling, down 1.24 ft over the past 24 hours. Over the past 30 days it has moved between 6.57 ft and 8.71 ft.
Fall is often low-water season on rivers, until steadier rain returns.
Judged against the official flood stage for this gauge. How to read levels
Key numbers
- Highest on record
- 43.10 ftMay 24, 2015
What the stage means on the water
A normal level is usually prime time for floating and wade fishing, as long as the weather holds upstream.
The National Weather Service puts flood stage for this gauge at 18.00 ft, still 10.57 ft away.
What happens at each level
- 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
- 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
- 24.00 ft
- Lowest homes are threatened. Water beings to cut off secondary roads near the river
- 18.00 ft
- Roadways and low bridges along the river are flooded. Vehicles cannot pass. Livestock can be stranded.
- 13.00 ft
- Overbank conditions may cut off livestock and low bridges near the river
- 7.43 ft
- Right now
Impact statements from the U.S. National Weather Service.
Highest crests on record
Chance of at least minor flooding in October to December: 19 %.
| Rank | Level | Date |
|---|---|---|
| 1 | 43.10 ft | May 24, 2015 |
| 2 | 42.56 ft | October 30, 2015 |
| 3 | 24.71 ft | October 14, 2021 |
| 4 | 24.14 ft | May 9, 2019 |
| 5 | 20.53 ft | May 4, 2019 |
| 6 | 15.23 ft | September 26, 2016 |
| 7 | 13.49 ft | April 11, 2017 |
| 8 | 10.93 ft | August 27, 2017 |
Weather at the gauge
The forecast is not available right now.
Map
Other gauges on the Blanco River
| Gauge | Level | Compared with normal | 24 hours | Distance |
|---|---|---|---|---|
| Blanco River at Crabapple Rd near BlancoRiver gauge, Blanco River | 0.56 ft | Normal | −0.88 ft | 39 mi |
| Blanco River at BlancoRiver gauge, Blanco River | 12.40 ft | No reference yet | −0.03 ft | 34 mi |
| Blanco River at Valley View Rd near FischerRiver gauge, Blanco River | 1.91 ft | No reference yet | ±0 | 22 mi |
| Blanco River at Fischer Store Rd near FischerRiver gauge, Blanco River | 3.64 ft | Below flood stage | −18.03 ft | 19 mi |
| Blanco River at WimberleyRiver gauge, Blanco River | 3.50 ft | Low | −0.01 ft | 13 mi |
| Blanco River at Halifax Rch near KyleRiver gauge, Blanco River | 0.84 ft | Low | −0.01 ft | 9 mi |
| Blanco River near KyleRiver gauge, Blanco River | 2.96 ft | Low | −23.21 ft | 7 mi |
Nearby gauges
| Gauge | Level | Compared with normal | 24 hours | Distance |
|---|---|---|---|---|
| San Marcos River at San MarcosRiver gauge, San Marcos River | 3.65 ft | Low | +0.02 ft | 1.6 mi |
| San Marcos River near MartindaleRiver gauge, San Marcos River | 7.43 ft | Normal | ±0 | 5.2 mi |
| Plum Creek at LockhartRiver gauge, Plum Creek | 2.02 ft | Normal | −0.11 ft | 14 mi |
| Onion Creek near DriftwoodRiver gauge, Onion Creek | 1.15 ft | Normal | −0.03 ft | 15 mi |
| Guadalupe River at Third Crossing near SattlerRiver gauge, Guadalupe River | 3.80 ft | Normal | +0.02 ft | 16 mi |
| Hueco Spgs near New BraunfelsRiver gauge, Hueco Spgs | 7.13 ft | Normal | −0.01 ft | 16 mi |
| Guadalupe River at SattlerRiver gauge, Guadalupe River | 4.45 ft | Normal | ±0 | 16 mi |
Questions and answers
What is flood stage for the Blanco River at San Marcos?
The official flood stage is 18.00 ft. The level is currently 10.57 ft below it.
Is gage height the same as water depth?
No. Gage height is measured from a fixed reference point chosen by the agency, so a reading of 10 ft does not mean the river is 10 ft deep.
What is the water level of Blanco River at San Marcos today?
On Oct 17, 2026, 08:45 PM CDT, the water level was 7.43 ft. Down 1.24 ft over the last 24 hours.
Is Blanco River at San Marcos rising or falling?
Down 1.24 ft over the last 24 hours.
Is the level of Blanco River at San Marcos normal?
Below flood stage. Judged against the official flood stage for this gauge.
What is the highest water level ever recorded at Blanco River at San Marcos?
The highest level on record is 43.10 ft on May 24, 2015.
How often is this data updated?
The U.S. Geological Survey publishes a new reading every 15 minutes. This page refreshes within minutes of each update.
For specialists
Station codes, datum, parameters, data quality and downloads
- Operator
- U.S. Geological Survey
- Station code
usgs:08171350(Agency page)- Coordinates
29.87951, -97.91075(WGS84)- Vertical datum
- NAVD88
- Update interval
- every 15 minutes
- Licence
- Public domain. Data: U.S. Geological Survey (USGS), provisional data subject to revision
Published series
| Parameter | Last value | Time (UTC) | Quality |
|---|---|---|---|
| Water level | 7.43 ft | 2026-10-18 01:45 | Provisional |
| Flow | 0.0 cfs | 2026-10-18 01:45 | Provisional |
Download
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How to cite
U.S. Geological Survey: Blanco River at San Marcos (usgs:08171350). Accessed October 18, 2026 via Nivelmap, https://nivelmap.com/en/united-states/texas/blanco-river-at-san-marcos
How we check values
Each reading is stored as published. We hold back values that jump faster than physically plausible and show the measurement time with every value.
Readings are provisional, can be delayed or wrong and are not a flood warning. Read the disclaimer