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Scheduled Maintenance Notice
USGS will be performing maintenance on the time series data processing system beginning at 09:00 EDT on September 10, 2026. During this period, delivery of the latest time series data will be delayed. The maintenance is expected to finish within 2 hours, after which all backlogged time series data will be processed and delivered to WDFN web portals and APIs.

Available data

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0 data types available

2 data types available - data from 1977-10-01 to 1983-10-12

0 data types available

35 Observed properties (data types) available - with data from 1979-12-31 to 1983-06-13

18 Sampling activities

2 data types available - with data from 1978-01-17 to 1983-01-24

2 data types available - data from 1977-10-01 to 1983-10-12

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Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	11176180	n/a
Location name	ARROYO LAS POSITAS A ELCH RD NR PLEASANTON CA	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	37.696874323076	n/a
Decimal longitude (WGS84)	-121.849400285426	n/a
Latitude-longitude method	Interpolated from map	M
Latitude-longitude accuracy	Accurate to + or - 5 sec.	F
District	California	06
State	California	06
County	Alameda County	001
Country	United States of America	n/a
Altitude of gage/land surface		n/a
Method altitude determined		n/a
Altitude accuracy		n/a
Altitude datum		n/a
Subbasin hydrologic unit	San Francisco Bay	18050004
Drainage basin		n/a
Date of first construction		n/a
Drainage area	75 square miles	n/a
Contributing drainage area		n/a
Time zone abbreviation	PST	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