Whitemarsh Run At White Marsh flow report
As of July 13, 2026, Whitemarsh Run At White Marsh is flowing at 1 cfs with a gage height of 3.26 ft, receding 19% over the past 24 hours. Source: USGS gauge #01585100, refreshed throughout the day.
Historical Data
Whitemarsh Run At White Marsh at a glance
How Whitemarsh Run At White Marsh is running right now, where it sits on the map, and the key gauge stats.
Whitemarsh Run At White Marsh is flowing at 1 cfs, with the water sitting 3.26 ft at the gage. Flow is down 19% since yesterday as the gauge recedes.
This is USGS gauge #01585100 in Maryland. Over the past 10 days the average has been 15 cfs, peaking at 103 cfs.
Over the next 5 days, Whitemarsh Run At White Marsh is expected to recede from today's 2 cfs, toward roughly 1 cfs by 2026-07-17 (likely range 0-4 cfs) -- running well below the seasonal normal.
For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the Maryland flow report.
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.
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.
Weather Forecast
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day forecast
Daily temperatures, snow, and rain projected over the next two weeks.
Whitemarsh Run At White Marsh
The stream is fed by various tributaries and drains into the Gunpowder River. The primary constituents of the flow are precipitation and groundwater. The flow is influenced by seasonal trends, with higher flow during the winter and spring months due to increased precipitation and snowmelt. There are no major dams on the creek. Interesting facts about the hydrology of the Whitemarsh Run include its designation as an impaired waterway by the EPA due to high levels of bacteria and nutrients, as well as its designation as a "blueway" by the Maryland Department of Natural Resources, indicating its importance for recreational use.
Nearby streamflow levels
Cross-check Whitemarsh Run At White Marsh's discharge against nearby gauges to spot whether the change here is local or regional.
| Gauge | Streamflow |
|---|---|
| Whitemarsh Run At White Marsh | 1 cfs |
| Honeygo Run Near White Marsh | 0 cfs |
| Whitemarsh Run Near Fullerton | 1 cfs |
| Moores Run At Radecke Ave At Baltimore | 0 cfs |
| Long Green Creek At Glen Arm | 3 cfs |
| Minebank Run Near Glen Arm | 1 cfs |
Nearby snowpack data
Snowpack at SNOTEL stations near Whitemarsh Run At White Marsh. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.
| SNOTEL station | Snowpack |
|---|---|
| Cylburn Coop | 0 in |
| Jarrettsville 4.2 E | 0 in |
| Reisterstown Automated Coop | 0 in |
| Norrisville 0.6 Wsw | 0 in |
| Susquehanna River At Conowingo | 0 in |
| Eldersburg 0.9 E | 0 in |
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 Whitemarsh Run At White Marsh in the Snoflo app
Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when Whitemarsh Run At White Marsh crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.
About Whitemarsh Run At White Marsh
Where does the streamflow data for Whitemarsh Run At White Marsh come from?
Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 01585100. 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 Whitemarsh Run At White Marsh 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.
Access the free Whitemarsh Run At White Marsh report
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