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Available data

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Continuous data

2 data types available - data from 2015-01-22 to 2026-08-01

Daily data

1 data types available - data from 2015-01-22 to 2026-07-30

Field measurements

2 data types available - data from 2015-04-06 to 2026-06-30

Discrete sample data

0 observed properties (data types) available

Statistical tables for select daily data types

1 data types available - data from 2015-01-22 to 2026-07-30

Important information about this monitoring location

The elevation of this station has been determined to be 542.97 feet above NAVD 1988. To obtain stream water-surface elevation values in NAVD 1988, add 542.97 feet to gage height values.

Location details and information

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Operated in cooperation with:

Guadalupe-Blanco River Authority

Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	08171350	n/a
Location name	Blanco Rv at San Marcos, TX	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	29.8795111111111	n/a
Decimal longitude (WGS84)	-97.9107527777778	n/a
Latitude-longitude method	Interpolated from Digital MAP.	N
Latitude-longitude accuracy	Accurate to + or - .5 sec (PLGR/PPS GPS).	5
District	Texas	48
State	Texas	48
County	Hays County	209
Country	United States of America	n/a
Altitude of gage/land surface	542.97 feet	n/a
Method altitude determined	GNSS2 - Level 2 Quality Survey Grade Global Navigation Satellite System	X
Altitude accuracy	0.02 feet	n/a
Altitude datum	North American Vertical Datum of 1988	NAVD88
Subbasin hydrologic unit	San Marcos	12100203
Drainage basin	18	n/a
Date of first construction		n/a
Drainage area	436 square miles	n/a
Contributing drainage area		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 Blanco Rv at San Marcos, TX - USGS-08171350