Unnamed Tributary below New Alexandria Tide Gate

Highest listed crest 6.19 ftFlood stage 5.5 ft1 crests since 2021

The Unnamed Tributary below New Alexandria Tide Gate crested above flood stage 1 time among the 1 crests the National Weather Service lists from 2021 to 2021. The highest, 6.19 ft on October 29, 2021, was minor flooding, 0.69 feet above flood stage. 1 other gauge on the Unnamed Tributary crested above flood stage within a week of it.

The gauge

Highest listed crest: 6.19 ft; October 29, 2021
Flood stage: 5.5 ft; Major flooding from 7.5 ft
Crests at major: 0; 1 above flood stage
Most recent flood crest: October 29, 2021; 6.19 ft, minor flooding
Location: Fairfax County; Near Alexandria (3.4 mi), Washington (9.1 mi), Falls Church (9.9 mi)
Identifiers: NWS NADV2; No USGS station

Flood stages

The thresholds the National Weather Service uses for this gauge today, and how many listed crests reached each.

Flood categories, Unnamed Tributary below New Alexandria Tide Gate

Action stage	4.0	0	—	The level at which the NWS or its partners begin to take action
Flood stage (minor)	5.5	1	Oct 29, 2021	Minimal or no property damage, but possibly some public threat
Moderate flood stage	6.5	0	—	Some inundation of structures and roads near the stream
Major flood stage	7.5	0	—	Extensive inundation of structures and roads

Every listed crest

1 crests from 2021 to 2021. 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

Highest listed crests, Unnamed Tributary below New Alexandria Tide Gate

1	Oct 29, 2021	6.19	+0.69	Minor	—

The worst floods along the Unnamed Tributary

For this gauge's highest crests, the other gauges on the Unnamed Tributary that crested above flood stage within a week.

October 29, 2021: 6.19 ft here, minor flooding

New Alexandria Storm Water Pumping Station - DownstreamVA · Oct 29, 2021 · 6.42 ft · Minor

Gauges on the Unnamed Tributary

Flood gauges sharing the river's name, linked within 80 miles of one another.

Flood gauges on the Unnamed Tributary

New Alexandria Storm Water Pumping Station - Downstream	VA	5.5	7.51 ft, Jul 8, 2019	1
New Alexandria Tide Gate this gauge	VA	5.5	6.19 ft, Oct 29, 2021	0
Middle River	MD	10.8	13.06 ft, Aug 7, 2018	0

Other gauges in Fairfax County

Flood gauges in Fairfax County

Woodburn Road / Strathmeade Springs	251.5	258.68 ft, Jul 13, 2025	0
Annandale	9.5	16.32 ft, Sep 8, 2011	3
Manassas Park	12.0	20.20 ft, Jul 22, 2018	0
Huntington - Metro Bridge	11.0	12.92 ft, Sep 9, 2011	0
McLean	9.0	10.54 ft, Dec 25, 2022	0
Browns Mill Road / Wolf Trap	195.0	196.37 ft, Jul 13, 2025	0
Great Falls	11.0	21.40 ft, Jun 22, 1972	1
Chantilly	9.0	9.21 ft, Sep 8, 2011	0
Fairview Lake	318.0	318.47 ft, Sep 8, 2011	0
New Alexandria Storm Water Pumping Station - Downstream	5.5	7.51 ft, Jul 8, 2019	1

Fairfax County: every hazard · River floods across the country · Virginia

NOAA National Water Prediction Service, gauge NADV2, 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.