Available data

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9 data types available - data from 2003-10-01 to 2026-08-08

7 data types available - data from 1935-04-01 to 2026-08-08

7 data types available - data from 1935-02-12 to 2026-07-06

794 Observed properties (data types) available - with data from 1945-04-03 to 2026-07-29

356 Sampling activities

2 data types available - with data from 1935-09-06 to 2025-07-13

5 data types available - data from 1935-04-01 to 2026-08-06

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Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	01646000	n/a
Location name	DIFFICULT RUN NEAR GREAT FALLS, VA	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	38.9759434630746	n/a
Decimal longitude (WGS84)	-77.2458143866351	n/a
Latitude-longitude method	Interpolated from MAP.	M
Latitude-longitude accuracy	Unknown or unspecified.	U
District	Virginia	51
State	Virginia	51
County	Fairfax County	059
Country	United States of America	n/a
Altitude of gage/land surface	150.94 feet	n/a
Method altitude determined	GNSS3 - Level 3 Quality Survey Grade Global Navigation Satellite System	Y
Altitude accuracy	0.13 feet	n/a
Altitude datum	North American Vertical Datum of 1988	NAVD88
Subbasin hydrologic unit	Middle Potomac-Catoctin	02070008
Drainage basin		n/a
Date of first construction		n/a
Drainage area	57.8 square miles	n/a
Contributing drainage area		n/a
Time zone abbreviation	EST	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