USGS Water-Year Summary 2024
02077303 HYCO RIVER BELOW AFTERBAY DAM NEAR MCGEHEES MILL, NC
LOCATION - Lat 36°31'21.8", long 78°59'49.4" referenced to North American Datum of 1983, Person County, NC, Hydrologic Unit 03010104, on left bank 200 ft downstream from Afterbay Reservoir dam of Progress Energy, 1.2 mi upstream from Ghent Creek, and 1.8 mi east-northeast of McGehees Mill.
DRAINAGE AREA - 202 mi².
REVISIONS HISTORY -
WDR NC-81-1: Drainage area.
Discharge from April 7, 2017 to July 10, 2018 revised based on changes to shifts from the base rating.
Water temperature data for the periods Oct. 18, 2017 to Feb 26, 2018 and May 17, 2018 to Sept. 30, 2018 were revised on April 9, 2019, based on the deletion of data that do not meet quality assurance standards.
Discharge data for the period from 08/09/2018 to 02/06/2019 were revised after approval on July 11, 2019 to apply shifts to the new rating and estimate periods of backwater.
Discharge data for the period from 02/06/2020 to 02/07/2020 and 02/11/2020 to 02/16/2020 were revised after approval on 06/01/2020 to estimate periods of backwater.
Water temperature data for the periods Oct. 26, 1985, Nov. 27, 1985, May 14, 1997, May 16, 1997, July 29, 1995, April 15, 1997 to April 16, 1997, June 26, 1997 to July 25, 1997, Oct. 16, 2008 to Oct. 17, 2008, Nov. 23, 2016, and July 21, 2017 to July 24, 2017 were revised on April 12, 2022 based on deletion of erroneous data.
SURFACE-WATER RECORDS
PERIOD OF RECORD - October 1973 to current year. August 1964 to September 1973, published as "Hyco River at McGehees Mill, NC" (02077300).
GAGE - Water-stage recorder. Datum of gage is 342.98 ft above National Geodetic Vertical Datum of 1929. From August 1964 to September 1973, records published as "Hyco River at McGehees Mill, NC" (02077300) at site 2.8 mi upstream, at datum 349.78 ft. Water-temperature recorder operated at site 600 ft downstream on right bank from June 1974 to September 1995. Satellite telemetry at streamgage.
The datum of the gage is 342.0 ft above NAVD88 NAD83(2011) Geoid 18 as determined by a level III static GNSS observation performed on September 18, 2019.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge 11,300 ft³/s, July 14, 1975, Maximum gage height 24.40 ft, July 14, 1975.
WATER-QUALITY RECORDS
PERIOD OF RECORD - Water years 1974 to current year.
PERIOD OF DAILY RECORD -
SPECIFIC CONDUCTANCE: October 1981 to September 1983.
WATER TEMPERATURE: June 1974 to current year.
INSTRUMENTATION - Temperature recorder since June 1974. Water-quality monitor from October 1981 to September 1983.
EXTREMES FOR PERIOD OF DAILY RECORD - SPECIFIC CONDUCTANCE: Maximum, 197 microsiemens, December 6, 1981; minimum, 89 microsiemens, May 16, 1983.
WATER TEMPERATURE: Maximum recorded, 33.5°C, July 20, 21, 22, 1977; minimum recorded, 1.0°C, January 6, 2002.