Tailwater · Mixed · Maine

West Branch Penobscot River

West Branch Penobscot River terrain map

The West Branch below Ripogenus is the flagship of Maine fly fishing — a big, cold, dam-controlled river running through the Golden Road country toward Katahdin, holding strong landlocked salmon and native brook trout in fast, broken water that smells of spruce and woodsmoke.

Prime · Brook Trout
Slate Drake · 10-14
Primelive now
About as good as it gets
Low and clear — careful approach country. Take your time — read the water before you cast.
75% confidence
What moved it
  • LevelDry recentlyNo gauge reading
  • Water temp10.3°C
  • ClarityClear
Today's fly
SD
Slate Drake10-14
Proven pattern for this period
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp10.3°C
ClarityClear
Weather16°C
WindSE 23 km/h
Pressure998 hPa
Rain · recent0.0 mm
Rain · ahead5.1 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Water temperature for Brook Trout
Ideal
10°C est.ideal 1016°C
0°14°28°
How to fish it · for Brook Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Why this works
Excellent — water temperature is working for you, but time of day is the limiting factor today.
Hatch timeline · todayQuiet day

Hatch predictions

Today's headline hatch shown — see all 3 active hatches hour by hour with Pro.

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Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 3 guilds with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

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Evidence
ModelledModerate confidence

Modelled from regional ecology — no survey or occurrence data for this water yet.

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
1
SulphurHatch
2
3
2
Trico (Eastern)Hatch
2
3
3
2
Eastern Blue-Winged OliveHatch
2
3
3
3
3
3
3
3
2
Eastern Summer BWO (Drunella)Hatch
2
3
3
2

Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.

Ranked for today
Brook Trout fly box
Local fly shops: New England Fly Co.
Permits & access
Permit required — see local rules.
  • Maine general law April 1–Sept 30; fly-only / special-law reaches apply — verify exact reaches against the Maine 2026 law book
  • DAM-RELEASE SAFETY: flow and whitewater character are set by Ripogenus releases — check Brookfield SafeWaters before wading; release changes are a safety matter.
What's coming
Plan ahead
5-day outlook
Other water nearby · 1
About this water

The West Branch below Ripogenus is the flagship of Maine fly fishing — a big, cold, dam-controlled river running through the Golden Road country toward Katahdin, holding strong landlocked salmon and native brook trout in fast, broken water that smells of spruce and woodsmoke. The salmon are the draw, chasing smelt and rising to caddis through the season; the brookies are the quiet bonus. It's release-driven water, so the flow you fish is what Ripogenus sends down, and the whitewater character means the dam schedule is a safety matter as much as a fishing one. Remote, beautiful, and serious: you fish it from the bank and by wading the edges, swinging and dead-drifting, and you keep an eye on the water level the whole time.

  • Mixed
Water quality · US Clean Water Act
  • Aquatic lifeSupporting
What this classification means

EPA ATTAINS assessment unit 'West Branch of Penobscot R' (ME0102000105_201R), 2024 Integrated Report. Aquatic Life use: Fully Supporting. This is a Clean Water Act assessment-unit classification (the US analogue of WFD), not a live reading.

Status is for the Clean Water Act assessment unit covering this reach.

EPA ATTAINS (Clean Water Act) · ME0102000105_201R

The full read · show the working · for Brook Trout · confidence 75%
How the 80 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time40 × 13%5.2
Pressure75 × 7%5.3
Insect activity56 × 12%6.7
Conditions total= 80
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
  • Trout1 April30 September
Related guides
Booking & contacts