Important Legacy real-time page

Available data

Select data types to graph from categories based on the way the data were collected.

Learn about the data collection categories

Continuous data

3 data types available - data from 1990-10-01 to 2026-08-28

Daily data

7 data types available - data from 1979-07-01 to 2026-08-27

Field measurements

2 data types available - data from 1961-11-07 to 2026-07-31

Discrete sample data

609 Observed properties (data types) available - with data from 1974-01-11 to 2025-07-15

238 Sampling activities

Peak measurements

2 data types available - with data from 1941-02-01 to 2025-06-12

Statistical tables for select daily data types

7 data types available - data from 1979-07-01 to 2026-08-26

Important information about this monitoring location

The elevation of this station has been determined to be 868.52 feet above NAVD 1988. To obtain stream water-surface elevation values in NAVD 1988 add 868.52 feet to gage height values.

Location details and information

Zoom out to see link to My Favorites

Use Explore USGS Water Data to discover additional data near this location

Operated in cooperation with:

City of Austin

USGS - Cooperative Matching Funds

Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	08158700	n/a
Location name	Onion Ck nr Driftwood, TX	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	30.0829892407753	n/a
Decimal longitude (WGS84)	-98.0077858912633	n/a
Latitude-longitude method	Interpolated from map	M
Latitude-longitude accuracy	Accurate to + or - 5 sec.	F
District	Texas	48
State	Texas	48
County	Hays County	209
Country	United States of America	n/a
Altitude of gage/land surface	868.52 feet	n/a
Method altitude determined	GNSS2 - Level 2 Quality Survey Grade Global Navigation Satellite System	X
Altitude accuracy	0.1 feet	n/a
Altitude datum	North American Vertical Datum of 1988	NAVD88
Subbasin hydrologic unit	Austin-Travis Lakes	12090205
Drainage basin		n/a
Date of first construction		n/a
Drainage area	124 square miles	n/a
Contributing drainage area	124 square miles	n/a
Time zone abbreviation	CST	n/a
Site honors Daylight Saving Time	Y	n/a
National aquifer		n/a
Local aquifer		n/a
Local aquifer type		n/a
Well depth		n/a
Hole depth		n/a
Source of depth data		n/a

Monitoring location Onion Ck nr Driftwood, TX - USGS-08158700