RIVER GAUGE · MILLSTONE RIVER
Millstone River at Blackwells Mills
Somerset County, New Jersey
Water level2.05 ft
Flow221 cfs
Last readingSep 16, 2026, 4:15 PM UTC (last recorded)
Action7 ft2,720 cfs
Minor flood9 ft
Moderate flood10 ft
Major flood15 ft
The past week
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What floods at each level
- 13 ft
Washington Street and several businesses are flooded.
- 10 ft
The D&R Canal is flooded by the Millstone River.
- 9 ft
Flood stage reached with flooding now along River Road in Blackwells Mills and S. River Street in Millstone. Base of Route 533 bridge floods. River Road between Yorktown and Amsterdam is subject to closure. Canal Road near Suydam Road floods.
- 7 ft
Several more causeways are closed due to flooding.
- 6 ft
The Griggstown Causeway is closed due to flooding.
Highest crests on record
| Date | Level | Flow |
|---|---|---|
| Aug 28, 2011 | 21.24 ft | 26,800 cfs |
| Sep 17, 1999 | 21.01 ft | 26,200 cfs |
| Sep 2, 2021 | 20.81 ft | 20,031 cfs |
Flood map
See which streets and areas flood at each water level here. Open the flood map ↗
More on Millstone River
UpstreamMillstone River at Griggstown
DownstreamMillstone River at Weston
Get an alert when Millstone River rises
Save this gauge in the free StormCast app and pick the level that matters to you. Your phone goes off when the water gets there.
