East Branch Penobscot River at Grindstone, Maine water level

Name: East Branch Penobscot River at Grindstone, Maine water level (U.S. Geological Survey)
Creator: U.S. Geological Survey
License: https://www.usgs.gov/information-policies-and-instructions/copyrights-and-credits

River gauge, East Branch Penobscot River, Maine, United States

Directions

Very low for mid-October

Water level

4.55ft Down 0.07 ft over the last 24 hours

Measured Oct 20, 2026, 05:00 PM EDT (30 min ago)

Flow: 380 cfs

History

7 days

Water level Normal range (10–90 %) Forecast Minor flood stage

The forecast expects the river to fall to 4.50 ft by Wednesday, October 21 at 02:00 PM. Issued Tuesday, October 20 at 10:49 AM by NOAA National Weather Service.

What this means

The East Branch Penobscot River at Grindstone, Maine is running far below normal at 4.55 ft.

That puts it 0.99 ft below the median of 5.54 ft for mid-October, based on 18 years of readings. It is 9.45 ft below the flood stage of 14.00 ft.

It has dropped 0.07 ft over the past 24 hours. The forecast expects the river to fall to 4.50 ft by Wednesday, October 21 at 02:00 PM. Without real rain upstream, that is unlikely to change quickly. In the last month it has stayed between 4.55 ft and 4.85 ft.

Compared with 18 years of daily readings for this time of year. How to read levels

Key numbers

Median for this date: 5.54 ft0.99 ft below the median for this date
Normal for this date: 4.77 ft – 7.77 ft8 years in 10 fall in this range (18 years of records)
Highest on record: 16.90 ftApril 30, 1923
Forecast peak: 4.60 ftTuesday, October 20 at 02:00 PM

Floating and fishing near East Branch Penobscot River at Grindstone, Maine

Low water exposes gravel bars that make good wading access, but some boat ramps may be left high and dry.

Flood stage here is 14.00 ft, 9.45 ft above the current reading. Beyond it, the National Weather Service also defines moderate and major flood stages.

What happens at each level

17.00 ft: Widespread flooding of State Route 11 from Hay Brook to Grindstone to Medway. Numerous homes, camps and campgrounds inundated. Flooding similar to April 1923. Penobscot River Trails inaccessible. Widespread flooding upstream to the Swift Brook Road in T3 R7 Wels.
16.00 ft: State Route 11 significantly flooded and impassable to all travel in several areas between Medway and the Penobscot River Trails in Grindstone. Homes and camps inundated. Logging roads west and near the river will be flooded. Hathaway Road flooded near the river.
14.50 ft: State Route 11 becomes impassable between the Penobscot River Trails road and Hay Brook with significant backwater flooding. Additional flooding of State Route 11 near Frazier Road to the Grindstone Falls Rest Area. 1-2 feet of inundation of State Route 11 near the USGS gage at the railroad trestle. Low lying structures are threatened downstream to Medway.
14.00 ft: State Route 11 flooded in places but remains passable. Homes and camps begin to get threatened. Significant flooding of Penobscot River Trails and unaccessable. Moderate backwater flooding of Mud & Hay Brooks.
13.00 ft: Minor flooding of the flood plain through Penobscot River Trails cutting some trails off from access.
12.00 ft: River rising nearing bankfull with minor floodplain flooding along the Penobscot River Trails.
4.55 ft: Right now

Impact statements from the U.S. National Weather Service.

Highest crests on record

Chance of at least minor flooding in October to December: < 5 %.

Rank	Level	Date
1	16.90 ft	April 30, 1923
2	15.02 ft	April 30, 2008
3	14.71 ft	April 29, 1973
4	14.67 ft	December 19, 2023
5	14.30 ft	September 29, 1909
6	14.00 ft	March 20, 1936
7	12.50 ft	April 28, 2019
8	12.49 ft	December 14, 2010
9	12.22 ft	April 27, 2018
10	11.87 ft	April 16, 2014

Weather at the gauge

No rain in the last 3 days.

20 Tue 58° 31° – Wind 10 mph

21 Wed 50° 32° – Wind 6 mph

22 Thu 55° 33° – Wind 13 mph

23 Fri 47° 32° – Wind 14 mph

24 Sat 56° 30° – Wind 5 mph

25 Sun 62° 33° – Wind 9 mph

26 Mon 63° 45° – Wind 6 mph

Forecast: Open-Meteo

Sunrise 06:58 AM Sunset 05:42 PM Daylight 10 hr, 43 min Waxing gibbous 71%

Map

Nearby gauges

Gauge	Level	Compared with normal	24 hours	Distance
Wytopitlock Stream near Wytopitlock MaineRiver gauge, Wytopitlock Stream	2.84 ft	Below flood stage	+0.07 ft	21 mi
Mattawamkeag River near Mattawamkeag, MaineRiver gauge, Mattawamkeag River	3.78 ft	Below flood stage	+0.10 ft	21 mi
Seboeis River near Shin Pond, MaineRiver gauge, Seboeis River	4.32 ft	Below flood stage	−0.02 ft	29 mi
E. Br. Penobscot River below Grand Lake MatagamonRiver gauge, E. Br. Penobscot River	2.48 ft	Below flood stage	−0.01 ft	30 mi
Penobscot River at West Enfield, MaineRiver gauge, Penobscot River	1.02 ft	Below flood stage	−0.73 ft	34 mi
Piscataquis River at Medford, MaineRiver gauge, Piscataquis River	2.20 ft	Below flood stage	±0	35 mi
Sebec River at Sebec, MaineRiver gauge, Sebec River	2.38 ft	Below flood stage	−0.15 ft	41 mi
Meduxnekeag R above S Br Medux. R near HoultonRiver gauge, Meduxnekeag R	2.33 ft	Below flood stage	−0.03 ft	43 mi

Questions and answers

What is flood stage for the East Branch Penobscot River at Grindstone, Maine?

The official flood stage is 14.00 ft. The level is currently 9.45 ft below it.

What is a normal level for the East Branch Penobscot River at Grindstone, Maine in mid-October?

The median for mid-October is 5.54 ft. In 8 years out of 10 the reading falls between 4.77 ft and 7.77 ft, based on 18 years of records.

Is gage height the same as water depth?

No. Gage height is measured from a fixed reference point chosen by the agency, so a reading of 10 ft does not mean the river is 10 ft deep.

What is the water level of East Branch Penobscot River at Grindstone, Maine today?

On Oct 20, 2026, 05:00 PM EDT, the water level was 4.55 ft. Down 0.07 ft over the last 24 hours.

Is East Branch Penobscot River at Grindstone, Maine rising or falling?

Down 0.07 ft over the last 24 hours.

Is the level of East Branch Penobscot River at Grindstone, Maine normal?

Very low for mid-October. Compared with 18 years of daily readings for this time of year.

What is the highest water level ever recorded at East Branch Penobscot River at Grindstone, Maine?

The highest level on record is 16.90 ft on April 30, 1923.

For specialists

Station codes, datum, parameters, data quality and downloads

Operator: U.S. Geological Survey
Station code: usgs:01029500 (Agency page)
Coordinates: 45.73028, -68.58944 (WGS84)
Vertical datum: NAVD88
Update interval: every 15 minutes
Licence: Public domain. Data: U.S. Geological Survey (USGS), provisional data subject to revision

Published series

Parameter	Last value	Time (UTC)	Quality
Water level	4.55 ft	2026-10-20 21:00	Provisional
Flow	380 cfs	2026-10-20 21:00	Provisional

Download

Embed this gauge

Add a live card for this gauge to your website. It updates on its own and links back here.

<iframe src="https://nivelmap.com/embed/5754?lang=en" width="360" height="230" style="border:0;max-width:100%" loading="lazy" title="East Branch Penobscot River at Grindstone, Maine water level"></iframe>

How to cite

U.S. Geological Survey: East Branch Penobscot River at Grindstone, Maine (usgs:01029500). Accessed October 20, 2026 via Nivelmap, https://nivelmap.com/en/united-states/maine/east-branch-penobscot-river-at-grindstone-maine

How we check values

Each reading is stored as published. We hold back values that jump faster than physically plausible and show the measurement time with every value.

Readings are provisional, can be delayed or wrong and are not a flood warning. Read the disclaimer