Coastal Flood Advisory
2026-07-13T05:00:00-04:00

* WHAT...Up to one half foot of inundation above ground level expected in low lying areas due to tidal flooding. * WHERE...Shoreline in Charles and King George Counties. * WHEN...Until 5 AM EDT Monday, especially around the time of high tide. * IMPACTS...At 3.5 feet, water reaches yards near Cobb Island and docks near Dahlgren. * ADDITIONAL DETAILS...Tides one to one and a half feet above normal. The next high tide at Goose Bay is at 3:10 AM. The next high tide at Dahlgren is at 2:13 AM.

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Coastal Flood Advisory
Until 2026-07-13T05:00:00-04:00 • National Weather Service
* WHAT...Up to one half foot of inundation above ground level expected in low lying areas due to tidal flooding. * WHERE...Shoreline in Charles and King George Counties. * WHEN...Until 5 AM EDT Monday, especially around the time of high tide. * IMPACTS...At 3.5 feet, water reaches yards near Cobb Island and docks near Dahlgren. * ADDITIONAL DETAILS...Tides one to one and a half feet above normal. The next high tide at Goose Bay is at 3:10 AM. The next high tide at Dahlgren is at 2:13 AM.

MATTAWOMAN CREEK NEAR POMONKEY, MD

Realtime Data • Report • Conditions

20

Discharge (cfs)

2.4

Gauge Height (ft)

USGS 01658000

Streamflow discharge was last observed at 20 cfs, and a gauge height of 2.39 feet. With the % decrease since yesterday, the streamflow average over the past 10 days is 12 .

Weather today, Tomorrow,

The creek is fed by several tributaries and contains several small dams. Seasonally, the creek experiences higher flows during the wetter months and lower flows during drier months. The hydrology of Mattawoman Creek is unique as it is one of the last free-flowing streams in the Washington, DC metropolitan area and is home to a diverse range of aquatic species. Additionally, the creek has been the focus of conservation efforts due to its important ecological value.

July 12, 2026

Elevation	46.0 ft
Last Updated
Gage height, ft	2.39 ft
Stream water level elevation above NAVD 1988, in ft	41.93 ft
Streamflow, ft³/s	19.5 ft3/s
Specific conductance, water, unfiltered, microsiemens per centimeter at 25°C	173.0 uS/cm @25C
Dissolved oxygen, water, unfiltered, mg/L	6.6 mg/l
Turbidity, water, unfiltered, monochrome near infra-red LED light, 780-900 nm, detection angle 90 ±2.5°, formazin nephelometric units (FNU)	4.6 FNU
pH, water, unfiltered, field, standard units	6.9 std units
Temperature, water, degC	22.9 deg C
Percent of Normal	131%
Year Over Year Average	15 cfs
24hr Flow Prediction	cfs
Maximum Recorded	4,090 cfs
Geolocation	38.60, -77.06

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Mattawoman Creek Near Pomonkey, Md Realtime Data

MATTAWOMAN CREEK NEAR POMONKEY, MD

Realtime Data • Report • Conditions

20

Discharge (cfs)

2.4

Gauge Height (ft)

July 12, 2026

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Mattawoman Creek Near Pomonkey, Md Realtime Data

MATTAWOMAN CREEK NEAR POMONKEY, MD

Realtime Data • Report • Conditions

20

Discharge (cfs)

2.4

Gauge Height (ft)

July 12, 2026

Seasonal Comparison

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