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Hydrograph River at a Glance Download
South Run at Lake Mercer Pool (ft)Observed: 216.21 ft at 10:10AM Sep 13, 2021Observed: 216.21 ft at 4:10PM Sep 13, 2021Observed: 216.19 ft at 10:10PM Sep 13, 2021Observed: 216.17 ft at 4:10AM Sep 14, 2021Observed: 216.17 ft at 10:10AM Sep 14, 2021Observed: 216.17 ft at 4:10PM Sep 14, 2021Observed: 216.17 ft at 10:10PM Sep 14, 2021Observed: 216.15 ft at 4:10AM Sep 15, 2021Observed: 216.15 ft at 10:10AM Sep 15, 2021Observed: 216.15 ft at 4:10PM Sep 15, 2021Observed: 216.11 ft at 11:10AM Sep 16, 2021Observed: 216.71 ft at 4:55PM Sep 16, 2021Observed: 216.85 ft at 5:10PM Sep 16, 2021Highest Observation: 216.91 ft at 11:10PM Sep 16, 2021Observed: 216.65 ft at 5:10AM Sep 17, 2021Observed: 216.53 ft at 11:10AM Sep 17, 2021Observed: 216.45 ft at 5:10PM Sep 17, 2021Observed: 216.41 ft at 11:10PM Sep 17, 2021Observed: 216.37 ft at 5:10AM Sep 18, 2021LMRV2(plotting HPIRR) Graph Created (7:11AM Sep 18, 2021)ObservedLatest observed value: 216.37 ft at 5:10 AM EDT 18-Sep-2021.
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NOTE: Forecasts are not available for the South Run at Lake Mercer. Only observed stages are available for this point.
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Latitude/Longitude Disclaimer: The gauge location shown in the above map is the approximate location based on the latitude/longitude coordinates provided to the NWS by the gauge owner.
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Latitude: 38.737778° N, Longitude: 77.254722° W, Horizontal Datum: NAD83/WGS84

River Stage
Reference Frame
Gauge Height Flood Stage Uses
NWS stage 0 ft Not Available  
Vertical Datum Elevation
(gauge height = 0)
(gauge height = flood stage)
Elevation information source
NAVD88 Not Available Not Available  
NGVD 29 Not Available Not Available  
MSL Not Available Not Available  
Other Not Available Not Available  
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(Baltimore/Washington) Sterling Weather Forecast Office
43858 Weather Service Rd.
Sterling, VA 20166
(703) 996-2200
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Page last modified: 2-Nov-2020 7:30 PM
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