Onion Creek near Driftwood, TX
River level and flood forecast · Hays County
Normal1.3 ftas of Mon 3:45 PM
The river is 4.2 ft below flood stage (5.5 ft).
Flow: 0 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Sun, Dec 31, 6 PM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 13 ft |
| Moderate flood stage | 7 ft |
| Flood stage | 5.5 ft |
| Action stage | 5.5 ft |
| Record crest (October 30, 2015) | 26.39 ft |
What floods at each level
From the National Weather Service, highest first.
- 25 ftMajor flooding is near the USGS survey 1:25 year level. Homes in a mobile home park downstream above William Cannon Drive in Austin will flood. Roads and bridges are severely flooded and very dangerous from the headwaters to the Colorado River.
- 23 ftMajor flooding makes roads and bridges very dangerous to auto traffic. A mobile home park downstream above William Cannon Drive in Austin will be threatened. Livestock should be moved from vulnerable areas of the flood plain.
- 20.5 ftMajor flooding is near the USGS survey 1:10 year level. Livestock are threatened in the flood plain. Roads and bridges are severely flooded and very dangerous from the headwaters to the Colorado River. A mobile home park downstream above William Cannon Drive in Austin will be threatened.
- 18 ftMajor flooding is well into the flood plain. Roads and bridges from the headwaters to the Colorado River in Austin are severely flooded and very dangerous. The two Ranch to Market Rd 150 crossings are under 13 feet of water.
- 15 ftMajor flooding is near the USGS survey 1:5 year level. Flow is ten feet over the two Ranch to Market Rd 150 crossings and well into the flood plain, threatening livestock. Roads and low bridges are flooded and dangerous from the headwaters to the Colorado River.
- 13 ftMajor flooding cuts off livestock in the flood plain from the headwaters to above I-35. Flow is eight feet over the two Ranch to Market Rd 150 crossings. Widespread severe flooding of secondary and primary roads and bridges makes driving very hazardous.
- 10 ftModerate lowland flooding is five feet over the two Ranch to Market Rd 150 crossings and well into the flood plain.
- 8.6 ftModerate flooding reaches the USGS survey 1:2 year flood level. Flow is three feet over the two Ranch to Market Rd 150 crossings.
- 7 ftModerate lowland flooding makes secondary roads, low bridges and low water crossings very dangerous. The two Ranch to Market Rd 150 crossings may be under several feet of fast flowing water.
- 5.5 ftMinor flooding makes several secondary roads dangerous, including the two Ranch to Market Rd 150 crossings over Onion Creek.
Highest crests on record
- 26.39 ft — October 30, 2015
- 26.3 ft — May 4, 2019
- 25.1 ft — October 17, 1998
- 21.56 ft — May 24, 2015
- 21.07 ft — October 31, 2013
Recent crests: 17 ft (May 8, 2019) · 26.3 ft (May 4, 2019) · 26.39 ft (October 30, 2015) · 10.89 ft (May 26, 2015) · 21.56 ft (May 24, 2015)
Up and down the river, and nearby
- Blanco River above at Halifax Ranch near Kyle, TX
- Bear Creek below Route 1826 at Driftwood, TX
- Blanco River at Wimberley, TX
- Bear Creek at Spillar Ranch Road, TX
- Blanco River near Kyle, TX
- Slaughter Creek at FM 1826 near Austin, TX
- Onion Creek at Twin Creeks near Manchaca, TX
- Slaughter Creek at FM 2304 near Manchaca 2NNE, TX
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (DRWT2); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.