Patapsco River at Ellicott City
Future / Actual / Minor
OWP 2.0 WWA Modal Title
01/11/2021, 10:04 PM UTC through 01/11/2021, 10:04 PM UTC
Sender
Sent
- Warning: no valid ratings curve available. Transformations to and from FEET/CFS/KCFS will not happen.No secondary data available. Transformations for Flow data and a secondary Y axis cannot be made at this time.
Traces and Thresholds Click to turn on/off display
Observed (OBS) 07/04/2025 4:45 PM EDTCATEGORY STAGE 
Major Flooding 127 ft Moderate Flooding 125 ft Minor Flooding 122.5 ft Action 121.5 ft Reliability of the Forecast:
NOTE: Forecasts are not available. Only observed stages are available for this point.
National Water Model Hydrograph
Official NWS streamflow forecasts are produced by NWS hydrologic forecasters for river gauge locations using hydrologic models which are calibrated to that location. This process considers additional guidance and information, including local expertise and experience, to produce the best forecast possible. The NWM output provides supplemental guidance to NWS forecasters and should not be considered an official NWS river forecast.
Flood Impacts
- 127 - Major flooding is occurring in lower Old Town Ellicott City. The flooding will be even more significant if local rainfall has occurred, causing additional backwater flooding.
- 125 - Main Street in Ellicott City is flooded near the railroad bridge with water either approaching or entering buildings. Backwater flooding may be occurring further upstream if local rainfall has occurred.
- 124 - Main Street in Ellicott City begins to flood both near 8000 Main Street and near the intersection of Main Street and Maryland Avenue.
Gauge Location
Recent Crests
| 1. | 122.60 ft | on 06-04-2018 |
| 2. | 124.78 ft | on 05-27-2018 |
Recent Crests
| 1. | 122.60 ft | on 06-04-2018 |
| 2. | 124.78 ft | on 05-27-2018 |
Historic Crests
| 1. | 124.78 ft | on 05-27-2018 |
| 2. | 122.60 ft | on 06-04-2018 |
Historic Crests
| 1. | 124.78 ft | on 05-27-2018 |
| 2. | 122.60 ft | on 06-04-2018 |
Vertical Datum Table
| type | NAVD88 |
|---|---|
| major Flooding | 127.00 ft |
| moderate Flooding | 125.00 ft |
| minor Flooding | 122.50 ft |
| action | 121.50 ft |
| Latest Value | 114.41 ft |
| Gauge Zero | 0.00 ft |
Gauge Photos
No Images Found
Probability Information
No Images Available
Collaborative Agencies
The National Weather Service prepares its forecasts and other services in collaboration with agencies like the US Geological Survey, US Bureau of Reclamation, US Army Corps of Engineers, Natural Resource Conservation Service, National Park Service, ALERT Users Group, Bureau of Indian Affairs, and many state and local emergency managers across the country. For details, please click here.