Flatlick Branch at Chantilly, VA
River level and flood forecast · Fairfax County
Normal1.6 ftas of Mon 4 PM
The river is 7.4 ft below flood stage (9 ft).
Flow: 22 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Sun, Dec 31, 7 PM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 15 ft |
| Moderate flood stage | 10 ft |
| Flood stage | 9 ft |
| Action stage | 6 ft |
| Record crest (September 8, 2011) | 9.21 ft |
What floods at each level
From the National Weather Service, highest first.
- 15 ftA few homes begin to flood along the stream between Route 50 and the mouth of the stream.
- 10 ftBuildings on the right bank begin to flood.
- 9 ftParking lots on the right bank begin to flood.
- 6 ftThe banks begin to overflow into nearby floodplain, but there is no impact to life or property.
Highest crests on record
- 9.21 ft — September 8, 2011
- 8.06 ft — July 12, 2013
- 7.07 ft — July 8, 2015
- 6.99 ft — May 11, 2008
- 6.99 ft — May 1, 2014
Recent crests: 6.68 ft (September 1, 2021) · 6.71 ft (August 15, 2019) · 6.14 ft (July 21, 2018) · 7.07 ft (July 8, 2015) · 6.99 ft (May 1, 2014)
Up and down the river, and nearby
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (CTYV2); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.