Mattawoman Creek Near Pomonkey flow report

Maryland, USA USGS #01658000 ↗

As of July 13, 2026, Mattawoman Creek Near Pomonkey is flowing at 6 cfs with a gage height of 2.17 ft, receding 66% over the past 24 hours. Source: USGS gauge #01658000, refreshed throughout the day.

⚠ Coastal Flood Advisory · Coastal Flood Advisory issued July 12 at 9:16PM EDT until July 13 at 5:00AM EDT by NWS Baltimore MD/Washington DC
Stale data This gauge hasn’t reported in days (last reading unknown). The readings below may not reflect current conditions.
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Right now · latest observation
Mattawoman Creek Near Pomonkey
USGS gauge #01658000
6 cfs streamflow
Latest reading from this gauge.
Gage height
2.17ft
Water temp
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% of median
Since yesterday
↓ -67%
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Conditions summary

Mattawoman Creek Near Pomonkey at a glance

How Mattawoman Creek Near Pomonkey is running right now, where it sits on the map, and the key gauge stats.

Mattawoman Creek Near Pomonkey is flowing at 6 cfs, with the water sitting 2.17 ft at the gage. Flow is down 66% since yesterday as the gauge recedes.

This is USGS gauge #01658000 in Maryland. Over the past 10 days the average has been 14 cfs, peaking at 33 cfs.

Over the next 5 days, Mattawoman Creek Near Pomonkey is expected to recede from today's 20 cfs, toward roughly 10 cfs by 2026-07-17 (likely range 1-82 cfs) -- drier than normal for the date.

For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the Maryland flow report.

Mattawoman Creek Near Pomonkey on the map Open map →
Site IDUSGS 01658000
Last updated2026-07-13
Gage height, ft2.17 ft
Stream water level elevation above NAVD 1988, in ft41.71 ft
Streamflow, ft³/s6.44 ft3/s
Specific conductance, water, unfiltered, microsiemens per centimeter at 25°C173.0 uS/cm @25C
Dissolved oxygen, water, unfiltered, mg/L6.6 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 units6.9 std units
Temperature, water, degC22.9 deg C
Max recorded4,090 cfs
Streamflow outlook

Streamflow Forecast

Powered by PULSE — Snoflo’s Predictive Unified Learning & Simulation Engine, which learns from how this river has answered every past storm, snowmelt, and dry spell to forecast where it’s headed with a precision generic models can’t match.

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Historical context

How does this compare to past years?

Year-over-year overlay, annual peak discharge, the full distribution of daily flows on record, and the gauge's rating curve.

Detailed forecast

Weather Forecast

Hourly detail

Next 5 days, hour by hour

Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.

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Deep dive

5-day forecast table

Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.

TimeConditionTemp (°F)Snow (in)Rain (in)Humidity (%)Wind (mps)Wind dir
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Long-term outlook

15-day forecast

Daily temperatures, snow, and rain projected over the next two weeks.

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About this location

Mattawoman Creek Near Pomonkey

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.

Regional streamflow

Nearby streamflow levels

Cross-check Mattawoman Creek Near Pomonkey's discharge against nearby gauges to spot whether the change here is local or regional.

Regional snowpack

Nearby snowpack data

Snowpack at SNOTEL stations near Mattawoman Creek Near Pomonkey. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.

Nearby recreation

Plan a trip

Reservoirs, boat launches, river runs, and fishing spots within driving distance of Mattawoman Creek Near Pomonkey.

River levels & flood safety

Read the level before you go
A river that's runnable at one flow can be deadly at another. Check current discharge and gage height — like the values shown above — against the flood-stage thresholds, and remember levels can spike fast after rain or a dam release.
Respect cold water
Snowmelt rivers run cold even in summer. Sudden immersion triggers cold-water shock and saps strength within minutes. Wear a PFD, dress for the water temperature (not the air), and never wade or paddle alone.
Watch for swiftwater hazards
Strainers (downed trees), undercut rocks, and low-head dams are the deadliest features on moving water. High, fast, muddy water hides them. If in doubt, scout from shore and portage.
Mind flash floods & releases
Narrow canyons can flood from a storm miles upstream, and dam-controlled reaches can rise without warning. Know the forecast, the release schedule, and your exit before you launch.

Track Mattawoman Creek Near Pomonkey in the Snoflo app

Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when Mattawoman Creek Near Pomonkey crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.

FAQ

About Mattawoman Creek Near Pomonkey

Where does the streamflow data for Mattawoman Creek Near Pomonkey come from?

Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 01658000. Snoflo refreshes the time series throughout the day. Forecasts come from the NOAA / yr.no feed Snoflo's iOS app uses.

How often is the report updated?

USGS gauges report continuously (typically every 15 minutes). Snoflo pulls fresh values throughout the day — look for the "as of" timestamp on the streamflow hero card.

What's the difference between discharge and gage height?

Discharge (cubic feet per second, or cfs) is the volume of water flowing past the gauge each second. Gage height is how high the water sits at the gauge (feet). They're related by a rating curve specific to each gauge — higher water means more flow, but the exact ratio depends on channel shape.

How is "percent of median" calculated?

Today's discharge is compared to the historical median discharge on this calendar day across the gauge's full record. 100% = right on median; 200% = a very high year; 30% = a drought-level low.

What are flood stages, and is this river safe right now?

Flood stages are NWS-defined gage-height thresholds — Action, Minor, Moderate, Major — marking when nearby roads or floodplains start to be affected. "Safe" depends on your activity and skill: a level that's a fun paddle for an expert can be lethal for a wader. Always check the current level against the thresholds above and the safety links, and when in doubt, stay off the water.

Can I get alerts when Mattawoman Creek Near Pomonkey rises?

Yes — flow alerts are managed in the Snoflo iOS app. Favorite this gauge, set a streamflow threshold (e.g. "alert me when discharge crosses 5,000 cfs"), and you'll get a push the moment USGS reports the crossing.