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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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Continuous data

5 data types available - data from 2010-10-08 to 2026-09-10

Daily data

5 data types available - data from 2010-10-01 to 2026-09-08

Field measurements

2 data types available - data from 2010-10-20 to 2026-09-02

Discrete sample data

42 Observed properties (data types) available - with data from 2010-10-19 to 2021-09-23
1955 Sampling activities

Peak measurements

2 data types available - with data from 2011-09-07 to 2025-08-01

Statistical tables for select daily data types

5 data types available - data from 2010-10-01 to 2026-09-08

Important information about this monitoring location

LOCATION.-- On left bank 50 ft upstream from bridge on Gun Road, in Patapsco Valley State Park, 0.9 mi northwest of Elkridge, 1.3 mi southwest of Halethorpe, and 4.5 mi east of Columbia. PERIOD OF RECORD.-- October 2010 to current year. GAGE.--Water-stage recorder and crest-stage gage. Datum of gage is 10.14 ft above North American Vertical Datum of 1988. REMARKS.--Flow regulated by Liberty Reservoir, approximately 21 mi upstream, beginning July 22, 1954, usable capacity, 42,070,000,000 gal; dead storage, 1,260,000,000 gal. Diversions upstream from station for municipal supply of Westminster (sewage effluent discharged into Little Pipe Creek), and from Liberty Reservoir beginning February 26, 1953, for municipal supply of Baltimore, and beginning February 1970 for a small municipal supply for part of Carroll County. PERIOD OF DAILY RECORD (Water Quality).-- TURBIDITY: October 2010 to October 2021. (Discontinued) SEDIMENT CONCENTRATION: October 2010 to October 2021. SEDIMENT LOAD: October 2010 to October 2021. REMARKS (Water Quality).-- Sediment discharge loads and concentrations were estimated for days of estimated daily discharges. Turbidity values greater than 1,600 nephelometric turbidity units (NTU) exceed the instrument calibration range. Values are included in the record but are presumed to have lower precision.

Monitoring locations with continuous data in last 120 days

No locations found

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