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Continuous data

3 data types available - data from 2024-03-26 to 2026-08-02

Daily data

1 data types available - data from 2024-03-26 to 2026-08-02

Field measurements

1 data types available - data from 2024-03-26 to 2026-06-24

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Important information about this monitoring location

LOCATION.-- At St Mary's River State Park Dam, on Western Branch Saint Marys River, 1.2 miles northwest of Callaway, MD. PERIOD OF RECORD.-- March 26, 2024 to current year GAGE.-- Water stage recorder and crest stage gage. Datum of gage is 220.40 ft above North American Vertical Datum of 1988. REMARKS.-- Tipping-bucket rain gage with site number 381510076320001 is located at station.

Location details and information

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Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	01661499	n/a
Location name	St Marys Lake near Callaway, MD	n/a
Site type	Lake, Reservoir, Impoundment	LK
Decimal latitude (WGS84)	38.25277777777778	n/a
Decimal longitude (WGS84)	-76.53347222222222	n/a
Latitude-longitude method	Interpolated from digital map	N
Latitude-longitude accuracy	Accurate to + or - .1 sec (Differentially-Corrected GPS).	1
District	Maryland	24
State	Maryland	24
County	St. Mary's County	037
Country	United States of America	n/a
Altitude of gage/land surface	-2.07 feet	n/a
Method altitude determined	GNSS2 - Level 2 Quality Survey Grade Global Navigation Satellite System	X
Altitude accuracy	0.13 feet	n/a
Altitude datum	North American Vertical Datum of 1988	NAVD88
Subbasin hydrologic unit	Lower Potomac	02070011
Drainage basin		n/a
Date of first construction		n/a
Drainage area	8.72 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

Monitoring location St Marys Lake near Callaway, MD - USGS-01661499