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Available data

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Continuous data

4 data types available - data from 2003-04-03 to 2026-08-08

Daily data

2 data types available - data from 2003-04-03 to 2026-08-07

Field measurements

2 data types available - data from 2003-04-01 to 2026-07-28

Discrete sample data

81 Observed properties (data types) available - with data from 2004-10-23 to 2005-05-29

3 Sampling activities

Peak measurements

2 data types available - with data from 2004-06-09 to 2025-02-11

Statistical tables for select daily data types

2 data types available - data from 2003-04-03 to 2026-08-07

Important information about this monitoring location

The elevation of this station has been determined to be 584.16 feet above NAVD 1988. To obtain stream water-surface elevation values in NAVD 1988 add 584.16 feet to gage height values

Location details and information

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Operated in cooperation with:

City of Austin

Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	08158827	n/a
Location name	Onion Ck at Twin Creeks Rd nr Manchaca, TX	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	30.1263234529586	n/a
Decimal longitude (WGS84)	-97.8211161263302	n/a
Latitude-longitude method	Interpolated from map	M
Latitude-longitude accuracy	Accurate to + or - 1 sec.	S
District	Texas	48
State	Texas	48
County	Travis County	453
Country	United States of America	n/a
Altitude of gage/land surface	584.16 feet	n/a
Method altitude determined	GNSS2 - Level 2 Quality Survey Grade Global Navigation Satellite System	X
Altitude accuracy	0.23 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	181 square miles	n/a
Contributing drainage area	181 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 at Twin Creeks Rd nr Manchaca, TX - USGS-08158827