Maryland River Levels & Streamflow
As of Sep 4, 2026, Maryland rivers are running at 99% of normal across 92 USGS gauges — the highest is 5,980 cfs on the Susquehanna River At Conowingo. Live discharge, gauge height, and percent-of-normal for every USGS streamgauge in Maryland.
Streamflow levels across Maryland are currently 99% of normal, with the Susquehanna River At Conowingo reporting the highest discharge in the state at 5,980 cfs and a gauge stage of 9.51 ft.
Meanwhile, the Susquehanna River At Conowingo is seeing a spike today — up 1% since yesterday and currently running near peak.
Tap any gauge below for the full hydrograph, paired weather forecast, and historical context. Use the rivers panel to jump into Maryland's named rivers.
Active weather warnings for Maryland
Maryland residents should prepare for potentially severe weather conditions Wednesday afternoon, with lingering rain expected throughout the day followed by afternoon thunderstorms capable of producing damaging winds and large hail. All areas of Maryland should remain alert and monitor local weather updates closely. Residents are advised to secure loose outdoor items, charge electronic devices, and have a weather radio available. Stay indoors during peak storm activity and avoid driving if conditions deteriorate. This threat affects communities statewide, including Baltimore, Annapolis, and all surrounding areas. Additional storms may develop as atmospheric conditions evolve, so continued vigilance is essential through Wednesday evening.
State-wide streamflow overview
The Maryland flow picture in four data points -- where the state sits versus historical norms, what's flowing hardest, and what's spiking fastest.
Percent of normal
100% is the historical norm. Below 70% indicates drought; above 130% can flag elevated flood risk.
Highest discharge
Gauge stage 9.51 ft
Biggest 24h spike
Now 5,980 cfs
Network coverage
USGS gauges feeding 0 named rivers in Maryland.
Where every gauge actually sits
One dot per Maryland streamgauge, placed by its own percent of normal. The state average is a single line through all of it.
Percent of normal compares today's discharge with the historical average for this calendar day. Tap any dot to open that gauge.
Maryland streamflow, three water years
Statewide percent of normal, every day since Aug 2023. The dotted line is normal.
799 daily readings from 91 reporting gauges. Percent of normal is today's statewide discharge against the historical average for the same calendar day — 100% is normal, not "good". The axis tops out at 250%: 35 readings above that — including the 454% peak in Apr 2024 — are drawn along the top edge, so a few flood days cannot flatten three years of everything else. The line breaks in 2 places where the record skips more than five days — those are gaps in reporting, not readings of zero.
Maryland USGS streamgauges
Every USGS gauge Snoflo tracks in Maryland. Sortable, quickly filterable. Numeric columns heat-mapped from light to deep. Tap any gauge for its full hydrograph and forecast.
| Streamgage | Streamflow | Gage height | Water temp | Air temp | Elevation | Watershed |
|---|---|---|---|---|---|---|
|
Susquehanna River At Conowingo, Md
7 hours ago · USGS 01578310 |
11,900 cfs | 10.67 ft | · | 71°F | 21 ft | Lower Susquehanna |
|
Potomac River Near Wash, Md
8 hours ago · USGS 01646500 |
2,550 cfs | 2.94 ft | 45°F | 74°F | 43 ft | Middle Potomac-Catoctin |
|
Potomac River At Point Of Rocks, Md
8 hours ago · USGS 01638500 |
1,980 cfs | 1.40 ft | 81°F | 72°F | 192 ft | Middle Potomac-Catoctin |
|
Potomac River At Hancock, Md
8 hours ago · USGS 01613000 |
925 cfs | 3.21 ft | · | 70°F | 396 ft | Conococheague-Opequon |
|
Potomac River At Paw Paw, Md
8 hours ago · USGS 01610000 |
772 cfs | 4.01 ft | · | 69°F | 501 ft | Cacapon-Town |
|
St Marys River At Great Mills, Md
8 hours ago · USGS 01661500 |
468 cfs | 4.72 ft | · | 75°F | 13 ft | Lower Potomac |
|
North Branch Potomac River Near Cumberland, Md
8 hours ago · USGS 01603000 |
460 cfs | 2.63 ft | · | 69°F | 589 ft | North Branch Potomac |
|
Casselman River At Grantsville, Md
7 hours ago · USGS 03078000 |
385 cfs | 2.31 ft | · | 65°F | 2,135 ft | Youghiogheny |
|
Monocacy River At Jug Bridge Near Frederick, Md
7 hours ago · USGS 01643000 |
310 cfs | 2.36 ft | · | 71°F | 231 ft | Monocacy |
|
Bear Creek At Friendsville, Md
7 hours ago · USGS 03076600 |
306 cfs | 2.78 ft | · | 68°F | 1,640 ft | Youghiogheny |
|
Youghiogheny River Near Oakland, Md
8 hours ago · USGS 03075500 |
265 cfs | 2.83 ft | · | 66°F | 2,370 ft | Youghiogheny |
|
North Branch Potomac River At Kitzmiller, Md
8 hours ago · USGS 01595500 |
242 cfs | 2.73 ft | · | 69°F | 1,575 ft | North Branch Potomac |
|
Conococheague Creek At Fairview, Md
5 hours ago · USGS 01614500 |
234 cfs | 1.93 ft | · | 71°F | 438 ft | Conococheague-Opequon |
|
Patuxent River Near Bowie, Md
7 hours ago · USGS 01594440 |
176 cfs | 4.62 ft | · | 74°F | 20 ft | Patuxent |
|
Youghiogheny River At Friendsville, Md
8 hours ago · USGS 03076500 |
164 cfs | 2.44 ft | 72°F | 68°F | 1,555 ft | Youghiogheny |
|
Antietam Creek Near Sharpsburg, Md
7 hours ago · USGS 01619500 |
162 cfs | 2.56 ft | · | 71°F | 367 ft | Conococheague-Opequon |
|
Gunpowder Falls At Glencoe, Md
8 hours ago · USGS 01582500 |
161 cfs | 1.44 ft | · | 71°F | 247 ft | Gunpowder-Patapsco |
|
Deer Creek Near Darlington, Md
8 hours ago · USGS 01580520 |
151 cfs | 1.68 ft | · | 72°F | 49 ft | Lower Susquehanna |
|
Monocacy River At Monocacy Blvd At Frederick, Md
8 hours ago · USGS 01642190 |
122 cfs | 1.81 ft | · | 72°F | 259 ft | Monocacy |
|
Gunpowder Falls Near Parkton, Md
8 hours ago · USGS 01581920 |
113 cfs | 2.00 ft | 63°F | 71°F | 352 ft | Gunpowder-Patapsco |
|
Big Elk Creek At Elk Mills, Md
8 hours ago · USGS 01495000 |
88 cfs | 3.67 ft | · | 72°F | 70 ft | Chester-Sassafras |
|
Deer Creek At Rocks, Md
8 hours ago · USGS 01580000 |
79 cfs | 2.26 ft | · | 71°F | 262 ft | Lower Susquehanna |
|
Piscataway Creek At Piscataway, Md
7 hours ago · USGS 01653600 |
79 cfs | 3.50 ft | · | 74°F | 16 ft | Middle Potomac-Anacostia-Occoquan |
|
Nassawango Creek Near Snow Hill, Md
7 hours ago · USGS 01485500 |
78 cfs | 3.70 ft | · | 75°F | 21 ft | Pocomoke |
|
North Branch Potomac River At Steyer, Md
8 hours ago · USGS 01595000 |
73 cfs | 2.42 ft | · | 67°F | 2,276 ft | North Branch Potomac |
|
Seneca Creek At Dawsonville, Md
8 hours ago · USGS 01645000 |
64 cfs | 2.04 ft | · | 72°F | 216 ft | Middle Potomac-Catoctin |
|
Savage Riv Bl Savage Riv Dam Near Bloomington, Md
8 hours ago · USGS 01597500 |
63 cfs | · | 59°F | 70°F | 1,382 ft | North Branch Potomac |
|
Antietam Creek Near Waynesboro, Md
8 hours ago · USGS 01619000 |
63 cfs | 2.46 ft | · | 71°F | 547 ft | Conococheague-Opequon |
|
Wills Creek Near Cumberland, Md
8 hours ago · USGS 01601500 |
62 cfs | 2.07 ft | · | 69°F | 703 ft | North Branch Potomac |
|
Patapsco River At Hollofield, Md
8 hours ago · USGS 01589000 |
59 cfs | 1.57 ft | · | 72°F | 190 ft | Gunpowder-Patapsco |
|
North East Branch Anacostia River At Riverdale, Md
7 hours ago · USGS 01649500 |
57 cfs | · | 78°F | 74°F | 14 ft | Middle Potomac-Anacostia-Occoquan |
|
Georges Creek At Franklin, Md
8 hours ago · USGS 01599000 |
53 cfs | 2.51 ft | · | 70°F | 975 ft | North Branch Potomac |
|
Western Branch At Upper Marlboro, Md
8 hours ago · USGS 01594526 |
45 cfs | 2.14 ft | · | 74°F | 9 ft | Patuxent |
|
Savage River Near Barton, Md
8 hours ago · USGS 01596500 |
40 cfs | 1.37 ft | 68°F | 67°F | 1,659 ft | North Branch Potomac |
|
Little Patuxent River At Savage, Md
8 hours ago · USGS 01594000 |
38 cfs | 3.08 ft | · | 73°F | 126 ft | Patuxent |
|
Little Falls At Blue Mount, Md
8 hours ago · USGS 01582000 |
36 cfs | · | · | 71°F | 306 ft | Gunpowder-Patapsco |
|
St Clement Creek Near Clements, Md
8 hours ago · USGS 01661050 |
32 cfs | · | · | 74°F | 11 ft | Lower Potomac |
|
Catoctin Creek Near Middletown, Md
8 hours ago · USGS 01637500 |
30 cfs | 1.79 ft | · | 71°F | 436 ft | Middle Potomac-Catoctin |
|
Gwynns Falls At Washington Blvd At Baltimore, Md
8 hours ago · USGS 01589352 |
30 cfs | 2.44 ft | · | 74°F | 18 ft | Gunpowder-Patapsco |
|
Tuckahoe Creek Near Ruthsburg, Md
8 hours ago · USGS 01491500 |
28 cfs | · | · | 73°F | 14 ft | Choptank |
|
Winters Run Near Benson, Md
8 hours ago · USGS 01581700 |
28 cfs | 1.40 ft | · | 72°F | 190 ft | Gunpowder-Patapsco |
|
Big Pipe Creek At Bruceville, Md
8 hours ago · USGS 01639500 |
27 cfs | · | · | 71°F | 370 ft | Monocacy |
|
Patuxent River Below Brighton Dam Near Brighton, Md
8 hours ago · USGS 01591610 |
26 cfs | 1.46 ft | 70°F | 72°F | 310 ft | Patuxent |
|
Monocacy River At Bridgeport, Md
7 hours ago · USGS 01639000 |
24 cfs | 2.47 ft | · | 70°F | 332 ft | Monocacy |
|
Little Patuxent River At Guilford, Md
8 hours ago · USGS 01593500 |
24 cfs | 2.18 ft | · | 72°F | 267 ft | Patuxent |
|
Bennett Creek At Park Mills, Md
8 hours ago · USGS 01643500 |
21 cfs | 1.55 ft | · | 72°F | 304 ft | Monocacy |
|
Little Gunpowder Falls At Laurel Brook, Md
8 hours ago · USGS 01584500 |
21 cfs | 1.15 ft | · | 72°F | 260 ft | Gunpowder-Patapsco |
|
Western Run At Western Run, Md
7 hours ago · USGS 01583500 |
20 cfs | · | · | 71°F | 265 ft | Gunpowder-Patapsco |
|
Patuxent Riv Near Laurel, Md
8 hours ago · USGS 01592500 |
19 cfs | 4.32 ft | · | 73°F | 160 ft | Patuxent |
|
North Branch Patapsco River At Cedarhurst, Md
8 hours ago · USGS 01586000 |
18 cfs | 1.32 ft | · | 71°F | 423 ft | Gunpowder-Patapsco |
|
Morgan Creek Near Kennedyville, Md
8 hours ago · USGS 01493500 |
15 cfs | 1.70 ft | · | 73°F | 4 ft | Chester-Sassafras |
|
Patuxent River Near Unity, Md
8 hours ago · USGS 01591000 |
15 cfs | 2.06 ft | · | 72°F | 383 ft | Patuxent |
|
Choptank River Near Greensboro, Md
8 hours ago · USGS 01491000 |
15 cfs | 2.17 ft | 79°F | 73°F | 5 ft | Choptank |
|
Gwynns Falls At Villa Nova, Md
7 hours ago · USGS 01589300 |
14 cfs | · | · | 72°F | 367 ft | Gunpowder-Patapsco |
|
Town Creek Near Oldtown, Md
8 hours ago · USGS 01609000 |
14 cfs | 1.94 ft | · | 68°F | 567 ft | Cacapon-Town |
|
Unicorn Branch Near Millington, Md
8 hours ago · USGS 01493000 |
14 cfs | 1.70 ft | · | 73°F | 8 ft | Chester-Sassafras |
|
Dead Run At Franklintown, Md
7 hours ago · USGS 01589330 |
12 cfs | · | · | 72°F | 313 ft | Gunpowder-Patapsco |
|
Cattail Creek Near Glenwood, Md
8 hours ago · USGS 01591400 |
12 cfs | · | · | 72°F | 382 ft | Patuxent |
|
Gunpowder Falls At Hoffmanville, Md
8 hours ago · USGS 01581810 |
11 cfs | 1.12 ft | · | 70°F | 550 ft | Gunpowder-Patapsco |
|
Hawlings River Near Sandy Spring, Md
8 hours ago · USGS 01591700 |
11 cfs | · | · | 72°F | 307 ft | Patuxent |
|
Zekiah Swamp Run Near Newtown, Md
8 hours ago · USGS 01660920 |
10 cfs | · | · | 73°F | 37 ft | Lower Potomac |
|
Beaverdam Run At Cockeysville, Md
7 hours ago · USGS 01583600 |
10 cfs | 2.13 ft | · | 71°F | 245 ft | Gunpowder-Patapsco |
|
Morgan Run Near Louisville, Md
8 hours ago · USGS 01586610 |
8 cfs | 1.33 ft | · | 71°F | 430 ft | Gunpowder-Patapsco |
|
Bynum Run At Bel Air, Md
8 hours ago · USGS 01581500 |
8 cfs | · | · | 72°F | 260 ft | Gunpowder-Patapsco |
|
Pocomoke River Near Willards, Md
8 hours ago · USGS 01485000 |
7 cfs | 4.65 ft | · | 73°F | 22 ft | Pocomoke |
|
Jones Falls At Sorrento, Md
8 hours ago · USGS 01589440 |
7 cfs | 7.79 ft | · | 72°F | 236 ft | Gunpowder-Patapsco |
|
Marsh Run At Grimes, Md
8 hours ago · USGS 01617800 |
7 cfs | 1.10 ft | · | 71°F | 405 ft | Conococheague-Opequon |
|
Whitemarsh Run At White Marsh, Md
7 hours ago · USGS 01585100 |
6 cfs | 3.16 ft | · | 73°F | 42 ft | Gunpowder-Patapsco |
|
Beetree Run At Bentley Springs, Md
8 hours ago · USGS 01581960 |
6 cfs | · | · | 71°F | 491 ft | Gunpowder-Patapsco |
|
Georges Run Near Beckleysville, Md
8 hours ago · USGS 01581870 |
6 cfs | · | · | 71°F | 521 ft | Gunpowder-Patapsco |
|
Chicamacomico River Near Salem, Md
8 hours ago · USGS 01490000 |
5 cfs | · | · | 74°F | 2 ft | Blackwater-Wicomico |
|
Nw Branch Anacostia River Near Colesville, Md
8 hours ago · USGS 01650500 |
5 cfs | 1.48 ft | · | 73°F | 271 ft | Middle Potomac-Anacostia-Occoquan |
|
Beaver Run Near Finksburg, Md
8 hours ago · USGS 01586210 |
4 cfs | · | · | 71°F | 431 ft | Gunpowder-Patapsco |
|
Piney Run At Dover, Md
7 hours ago · USGS 01583100 |
4 cfs | 1.40 ft | · | 71°F | 380 ft | Gunpowder-Patapsco |
|
Plumtree Run Near Bel Air, Md
7 hours ago · USGS 01581752 |
3 cfs | 1.20 ft | 73°F | 72°F | 187 ft | Gunpowder-Patapsco |
|
Sawmill Creek At Glen Burnie, Md
8 hours ago · USGS 01589500 |
3 cfs | 1.88 ft | · | 74°F | 34 ft | Gunpowder-Patapsco |
|
Grave Run Near Beckleysville, Md
8 hours ago · USGS 01581830 |
3 cfs | · | · | 71°F | 560 ft | Gunpowder-Patapsco |
|
Long Green Creek At Glen Arm, Md
8 hours ago · USGS 01584050 |
3 cfs | · | · | 72°F | 290 ft | Gunpowder-Patapsco |
|
Sideling Hill Creek Near Bellegrove, Md
8 hours ago · USGS 01610155 |
3 cfs | · | · | 68°F | 482 ft | Cacapon-Town |
|
Gwynns Falls Near Delight, Md
8 hours ago · USGS 01589197 |
3 cfs | · | · | 72°F | 536 ft | Gunpowder-Patapsco |
|
Sallie Harris Creek Near Carmichael, Md
8 hours ago · USGS 01492500 |
3 cfs | · | · | 74°F | 14 ft | Chester-Sassafras |
|
Manokin Branch Near Princess Anne, Md
8 hours ago · USGS 01486000 |
2 cfs | 1.58 ft | · | 75°F | 14 ft | Pocomoke |
|
East Branch Herbert Run At Arbutus, Md
7 hours ago · USGS 01589100 |
2 cfs | · | · | 74°F | 49 ft | Gunpowder-Patapsco |
|
Whitemarsh Run Near Fullerton, Md
8 hours ago · USGS 01585090 |
2 cfs | 1.17 ft | · | 73°F | 138 ft | Gunpowder-Patapsco |
|
Honeygo Run Near White Marsh, Md
8 hours ago · USGS 01585104 |
1 cfs | · | · | 73°F | 25 ft | Gunpowder-Patapsco |
|
Birch Branch At Showell, Md
8 hours ago · USGS 0148471320 |
1 cfs | 3.12 ft | · | 74°F | 6 ft | Chincoteague |
|
West Branch Herring Run At Idlewylde, Md
8 hours ago · USGS 01585200 |
1 cfs | · | · | 73°F | 286 ft | Gunpowder-Patapsco |
|
Minebank Run Near Glen Arm, Md
7 hours ago · USGS 0158397967 |
1 cfs | 4.10 ft | · | 72°F | 225 ft | Gunpowder-Patapsco |
|
Cranberry Branch Near Westminster, Md
7 hours ago · USGS 01585500 |
0 cfs | 1.24 ft | · | 71°F | 672 ft | Gunpowder-Patapsco |
|
Baisman Run At Broadmoor, Md
8 hours ago · USGS 01583580 |
0 cfs | 1.09 ft | · | 72°F | 333 ft | Gunpowder-Patapsco |
|
South Fork Jabez Branch At Millersville, Md
8 hours ago · USGS 01589795 |
0 cfs | 3.21 ft | · | 73°F | 60 ft | Severn |
|
Mattawoman Creek Near Pomonkey, Md
8 hours ago · USGS 01658000 |
0 cfs | 1.70 ft | 73°F | 73°F | 46 ft | Lower Potomac |
See every Maryland gauge ranked against normal.
- Percentile rank & % of median for all 92 gauges
- 15-day PULSE forecast on every gauge
- Custom flow alerts & full daily history
About Maryland streamflow
What are river levels like in Maryland right now?
As of September 4, 2026, Maryland rivers are running at 99% of normal across 92 USGS streamgauges, and the Susquehanna River At Conowingo is reporting the highest discharge at 5,980 cfs. The full sortable gauge table is below.
Which Maryland river is running highest right now?
As of September 4, 2026, the highest discharge in Maryland is 5,980 cfs on the Susquehanna River At Conowingo. See the sortable gauge table for the full statewide ranking.
Are Maryland rivers high or low right now?
Compare the statewide percent-of-normal on this page: above 100% means Maryland rivers are running higher than the seasonal average for the date, below 100% means lower (a dry spell or drought). Each gauge also shows its own percent of median.
Where does the Maryland streamflow data come from?
The U.S. Geological Survey National Water Information System. USGS streamgauges report continuously (every 15 minutes) and the data is the canonical real-time record for U.S. rivers. Snoflo pulls the latest readings and joins them to a 7-day NOAA weather forecast for each station.
What is cfs?
Cubic feet per second — the standard unit for streamflow. One cfs is about 7.5 gallons per second. Small creeks run at single-digit cfs; the Mississippi at hundreds of thousands.
What does Gauge Height mean?
The water level at the gauge in feet above the reference datum. Used together with discharge to track river state. Flood stage and runnable levels are typically expressed in gauge height (e.g., "flood at 16 ft").
How fresh is the Maryland data?
USGS streamgauges report every 15 minutes; Snoflo re-pulls throughout the day. The AI briefing regenerates daily.
Can I get a flow alert for a Maryland gauge?
Yes. Save any USGS gauge as a favorite in the Snoflo iOS app, set a discharge or stage threshold (e.g. "alert me when discharge crosses 2,000 cfs"), and you'll get a push the moment it crosses.
Is this a substitute for an NWS flood warning?
No. Snoflo is informational. For flood life-safety decisions always follow guidance from your local NWS forecast office and state emergency management. Snoflo data is one input among several.
Streamflow in every state
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