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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

1 data types available - data from 1977-09-15 to 1992-09-29

2 data types available - data from 1977-10-24 to 1992-11-03

222 Observed properties (data types) available - with data from 1977-10-24 to 1992-04-21

152 Sampling activities

2 data types available - with data from 1962-07-14 to 1992-04-19

1 data types available - data from 1977-09-15 to 1992-09-29

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Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	06326600	n/a
Location name	O'Fallon Creek near Ismay MT	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	46.4205694444444	n/a
Decimal longitude (WGS84)	-104.761022222222	n/a
Latitude-longitude method	Interpolated from digital map	N
Latitude-longitude accuracy	Accurate to + or - .1 sec (Differentially-Corrected GPS).	1
District	Montana	30
State	Montana	30
County	Fallon County	025
Country	United States of America	n/a
Altitude of gage/land surface	2590 feet	n/a
Method altitude determined	Interpolated from topographic map.	M
Altitude accuracy	10 feet	n/a
Altitude datum	National Geodetic Vertical Datum of 1929	NGVD29
Subbasin hydrologic unit	O'Fallon	10100005
Drainage basin		n/a
Date of first construction		n/a
Drainage area	663 square miles	n/a
Contributing drainage area		n/a
Time zone abbreviation	MST	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