Guana River below Guana River Dam (in MHHW)

Highest listed crest 1.84 ftFlood stage 1.7 ft2 crests since 2026

The Guana River below Guana River Dam (in MHHW) crested above flood stage 2 times among the 2 crests the National Weather Service lists from 2026 to 2026. The highest, 1.84 ft on September 24, 2026, was minor flooding, 0.14 feet above flood stage.

The gauge

Highest listed crest: 1.84 ft; September 24, 2026
Flood stage: 1.7 ft; Major flooding from 3.5 ft
Crests at major: 0; 2 above flood stage
Most recent flood crest: October 7, 2026; 1.70 ft, minor flooding
Location: St. Johns County; Near St. Augustine (8.8 mi)
Identifiers: NWS GRDF1; 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, Guana River below Guana River Dam (in MHHW)

Action stage	1.0	0	—	The level at which the NWS or its partners begin to take action
Flood stage (minor)	1.7	2	Oct 7, 2026	Minimal or no property damage, but possibly some public threat
Moderate flood stage	2.3	0	—	Some inundation of structures and roads near the stream
Major flood stage	3.5	0	—	Extensive inundation of structures and roads

Every listed crest

2 crests from 2026 to 2026. 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, Guana River below Guana River Dam (in MHHW)

1	Sep 24, 2026	1.84	+0.14	Minor	—
2	Oct 7, 2026	1.70	0.00	Minor	—

Other gauges in St. Johns County

Flood gauges in St. Johns County

Atlantic Ocean at Matanzas River Inlet Bridge (in MHHW)	2.5	4.10 ft, Oct 11, 2025	0
Spuds (in MHHW)	1.7	5.94 ft, Oct 10, 2024	7
Racetrack Road (in NAVD88)	3.0	9.04 ft, Sep 11, 1964	7
16th Street Culvert in St Augustine Beach (in NAVD88)	5.0	6.20 ft, Oct 9, 2026	0
A Street Canal in St Augustine Beach (in NAVD88)	6.0	7.16 ft, Oct 9, 2026	0
Mizell Outfall on Matanzas River (in MHHW)	3.1	4.22 ft, Oct 11, 2025	0
Faver Dykes State Park (in MHHW)	1.5	2.02 ft, Sep 24, 2026	0
Espanola (in MHHW)	0.6	4.34 ft, Sep 11, 2017	3
Racy Point (in MHHW)	1.5	4.41 ft, Oct 7, 2016	2
Racy Point (in MHHW)	1.5	4.41 ft, Oct 7, 2016	4
Shands Bridge (in MHHW)	1.5	3.66 ft, Oct 7, 2016	4
Tide Station at St Augustine Municipal Marina (in MHHW)	1.6	3.00 ft, Oct 11, 2025	0
St. Augustine Airport (in MHHW)	1.7	3.61 ft, Sep 11, 2017	2
St. Johns River (in MHHW)	1.5	2.48 ft, Oct 11, 2025	0

St. Johns County: every hazard · River floods across the country · Florida

NOAA National Water Prediction Service, gauge GRDF1, 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.