Patapsco River near Catonsville
Highest listed crest 27.15 ftFlood stage 20.0 ft11 crests since 2011
The Patapsco River near Catonsville crested above flood stage 8 times among the 11 crests the National Weather Service lists from 2011 to 2018. The highest, 27.15 ft on May 27, 2018, was moderate flooding, 7.15 feet above flood stage. 2 other gauges on the Patapsco River crested above flood stage within a week of it, 2 at their own highest listed crest.
The gauge
- Highest listed crest
- 27.15 ft
- May 27, 2018; 23,000 cubic feet per second
- Flood stage
- 20.0 ft
- No major stage set
- Crests at major
- 0
- 8 above flood stage
- Most recent flood crest
- September 10, 2018
- 20.39 ft, minor flooding
Flood stages
The thresholds the National Weather Service uses for this gauge today, and how many listed crests reached each.
| Action stage | 18.0 | 3 | Dec 16, 2018 |
| Flood stage (minor) | 20.0 | 5 | Sep 10, 2018 |
| Moderate flood stage | 25.0 | 3 | May 27, 2018 |
Every listed crest
11 crests from 2011 to 2018. Filled: at or above flood stage. Hover a crest for its date and stage.
- These are the crests the local National Weather Service office lists for the gauge: the highest on record and recent crests. Lesser floods between them may be missing, so counts by decade are a floor.
- Categories use today's flood stages. Levees, dams and channel changes since a crest can make old and new stages not directly comparable.
Highest crests
| 1 | May 27, 2018 | 27.15 | +7.15 | Moderate |
| 2 | Jul 31, 2016 | 27.14 | +7.14 | Moderate |
| 3 | Sep 7, 2011 | 25.17 | +5.17 | Moderate |
| 4 | Apr 30, 2014 | 23.83 | +3.83 | Minor |
| 5 | Jun 4, 2018 | 22.17 | +2.17 | Minor |
| 6 | Aug 4, 2018 | 22.17 | +2.17 | Minor |
| 7 | Jul 24, 2018 | 21.20 | +1.20 | Minor |
| 8 | Sep 10, 2018 | 20.39 | +0.39 | Minor |
| 9 | Dec 16, 2018 | 19.14 | −0.86 | Action |
| 10 | Nov 23, 2011 | 18.50 | −1.50 | Action |
| 11 | Jun 27, 2015 | 18.33 | −1.67 | Action |
The worst floods along the Patapsco River
For this gauge's highest crests, the other gauges on the Patapsco River that crested above flood stage within a week.
May 27, 2018: 27.15 ft here, moderate flooding
- Elkridge at Patapsco Valley State ParkMD · May 27, 2018 · 24.76 ft · Major · its highest
- Ellicott CityMD · May 27, 2018 · 124.78 ft · Minor · its highest
July 31, 2016: 27.14 ft here, moderate flooding
- Elkridge at Patapsco Valley State ParkMD · Jul 31, 2016 · 23.78 ft · Major
- HollofieldMD · Jul 31, 2016 · 14.24 ft · Minor
September 7, 2011: 25.17 ft here, moderate flooding
- Elkridge at Patapsco Valley State ParkMD · Sep 7, 2011 · 21.66 ft · Major
- HollofieldMD · Sep 7, 2011 · 12.62 ft · Minor
Gauges on the Patapsco River
Flood gauges sharing the river's name, linked within 80 miles of one another.
| Ellicott City | MD | 124.78 ft, May 27, 2018 | 0 |
| Hollofield | MD | 31.30 ft, Jun 22, 1972 | 1 |
| Catonsville this gauge | MD | 27.15 ft, May 27, 2018 | 0 |
| Elkridge at Patapsco Valley State Park | MD | 24.76 ft, May 27, 2018 | 4 |
| Elkridge below Patapsco Valley State Park | MD | 21.38 ft, Aug 4, 2018 | 0 |
Other gauges in Baltimore County
| Broadmoor | 6.08 ft, Jun 22, 1972 | 0 |
| Cockeysville | 12.10 ft, Jul 1, 1984 | 7 |
| Bentley Springs | 7.30 ft, Jul 25, 2018 | 0 |
| Woodlawn | 12.24 ft, Jul 30, 2016 | 0 |
| Franklintown | 12.50 ft, Jun 22, 1972 | 0 |
| Woodlawn | 12.16 ft, Jul 30, 2016 | 0 |
| Catonsville | 11.29 ft, Jul 30, 2016 | 0 |
| Arbutus | 13.25 ft, Aug 26, 1999 | 1 |
| Beckleysville | 7.27 ft, Jul 24, 2018 | 0 |
| Beckleysville | 7.85 ft, Jul 23, 2018 | 0 |
| Glencoe | 16.50 ft, Sep 8, 2011 | 9 |
| Hoffmanville | 10.02 ft, Aug 28, 2009 | 1 |
| Parkton | 11.62 ft, Sep 8, 2011 | 0 |
| Villa Nova | 21.50 ft, Jun 22, 1972 | 1 |
| White Marsh | 13.51 ft, Oct 19, 2024 | 0 |
| Sorrento | 18.11 ft, Jun 22, 1972 | 0 |
| Blue Mount | 18.54 ft, Jun 22, 1972 | 4 |
| Laurel Brook | 11.40 ft, Jul 1, 1984 | 0 |
| Glen Arm | 11.15 ft, Jul 14, 2015 | 0 |
| Ellicott City | 124.78 ft, May 27, 2018 | 0 |
| Hollofield | 31.30 ft, Jun 22, 1972 | 1 |
| Dover | 10.86 ft, Jul 24, 2018 | 0 |
| Rockdale | 7.83 ft, Jul 31, 2016 | 0 |
| Woodlawn | 8.15 ft, Jul 30, 2016 | 0 |
| Middle River | 13.06 ft, Aug 7, 2018 | 0 |
| Idlewylde | 10.87 ft, Aug 14, 2012 | 0 |
| Western Run | 26.00 ft, Jun 22, 1972 | 3 |
| White Marsh | 18.49 ft, Aug 1, 1971 | 1 |
Baltimore County: every hazard · River floods across the country · Maryland
NOAA National Water Prediction Service, gauge CTSM2, retrieved October 30, 2026. Stages in feet on the gauge's own datum, not elevation. Crests are as the National Weather Service lists them; preliminary values may be revised.