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Northwest Branch Patapsco River at Baltimore/Fort McHenry (IN ML — water level right now

Baltimore City, Maryland · NWS gauge BLTM2
Loading the latest reading…
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current stage (ft)
 
3.4
minor flood stage
 
9.77
record crest
set 2025-08-13
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flood status
official NWS category
Official NOAA forecast → Full US flood map →

Flood stages at this gauge

Where the water stands right now against the four official thresholds:

action · 2.5
minor · 3.4
moderate · 4.6
major · 6
Flood stageLevel (ft)What it means
Major flood stage6extensive inundation and significant evacuations — a serious event
Moderate flood stage4.6some buildings and roads inundated; evacuations possible
Minor flood stage3.4low-lying roads and fields near the river start to flood
Action stage2.5water is approaching flood level — time to pay attention

Highest floods on record here

#Crest (ft)Datevs. minor flood stage
19.772025-08-13+6.37 above
28.152003-09-19+4.75 above
37.691933-08-23+4.29 above
46.391955-08-13+2.99 above
55.852025-05-28+2.45 above
65.51954-10-15+2.1 above
75.312022-12-16+1.91 above
85.31915-08-04+1.9 above
95.181979-09-06+1.78 above
105.161996-09-07+1.76 above
115.131985-11-04+1.73 above
124.922021-10-30+1.52 above

Historic crests recorded at this gauge by the National Weather Service — the 12 highest on file.

Where this gauge is

The marker is this gauge; nearby gauges load live and are clickable.

Nearby river gauges

Gwynns Falls at Washington Blvd in Baltimore 4 mi away · loading… East Branch Herbert Run at Arbutus 6 mi away · loading… Sawmill Creek at Glen Burnie 7 mi away · loading… West Branch Herring Run at Idlewylde 7 mi away · loading… Dead Run at Franklintown 8 mi away · loading… Patapsco River near Elkridge at Patapsco Valley State Park 8 mi away · loading…

Gauge details

NWS gauge IDBLTM2
CountyBaltimore City
StateMaryland
NWS forecast officeSterling
River forecast centerMiddle Atlantic River Forecast Center
Coordinates39.27, -76.58
Time zoneEST5EDT
Turn Around, Don't Drown. Six inches of moving water can knock you off your feet and twelve inches can float a car. Never drive around barricades or into water of unknown depth — most flood deaths happen in vehicles.

Questions about Northwest Branch Patapsco River at Baltimore/Fort McHenry (IN ML

Is Northwest Branch Patapsco River at Baltimore/Fort McHenry (IN ML flooding right now?

The live reading at the top of this page answers that: the gauge is compared against its official NWS flood stages every 15 minutes. Minor flooding at this gauge begins at 3.4 ft. Blue means normal, yellow is action stage, orange minor, red moderate and dark red major flooding.

What is flood stage for Northwest Branch Patapsco River at Baltimore/Fort McHenry (IN ML?

major flood stage 6 ft, moderate flood stage 4.6 ft, minor flood stage 3.4 ft, action stage 2.5 ft. These are official National Weather Service thresholds set specifically for this gauge, not generic values.

What is the record flood at Northwest Branch Patapsco River at Baltimore/Fort McHenry (IN ML?

The highest crest on file at this gauge is 9.77 ft, reached on 2025-08-13 — that is 6.37 ft above minor flood stage. The full list of the highest crests is in the table on this page.

Where does this data come from?

From the NOAA National Water Prediction Service, the official U.S. river gauge network — a U.S. government work in the public domain. Live stage is refreshed every 15 minutes; flood thresholds and historic crests are refreshed monthly. For life-safety decisions follow NWS Sterling and local emergency management.