Freestone · Granite · Auvergne

Allier

A wide, tree-lined stretch of the River Allier flowing calmly past wooded hillsides in autumn near Coudes, Puy-de-Dôme, France.

The Allier is the Loire's great salmon tributary and the most important wild Atlantic salmon river left in mainland France.

Poor · Brown Trout
Small Perdigón · 16-20
New ruleReported 5 Aug 2026

Severe drought restrictions (alerte renforcée) in force

The Forez Ance - Mare - Bonson zone (Dept 42) is at alerte renforcée — the second-highest French drought tier — under a préfectoral arrêté. Fishing itself is not named as prohibited, but water is severely restricted and flows are likely very low; fish with care and check locally.

Arrêté préfectoral n°37590

Temporary notices from official orders and recent fishery reports — they clear automatically once out of date. Always confirm locally before travelling.

Poorlive now
Not the day for it
River temperature is the limiting factor today, not the flow. This is not the day to push it. Check the thermal advice above before you head out.
90% confidence
What moved it
  • Level0.06 m
  • Water temp23.0°C
  • ClarityClear
Today's fly
Small Perdigón
Small Perdigón16-20
Euro-nymph
Conditions on the water
Live gauge
Level
Steady
0.06 m
Water temp23.0°C
ClarityClear
Weather31°C
WindN 14 km/h
Pressure1020 hPa
Rain · recent0.3 mm
Rain · ahead0.9 mm

Live readings — water temperature is an estimate where the gauge does not record it.

Water temperature for Brown Trout
Warm — slow
23°C est.ideal 1016°C
0°14°28°
How to fish it · for Brown Trout
When
Through the open trout season — opens 2nd Saturday of March; spring olives and grannom; sedges through summer; small dark flies into autumn close.
Where
The lower and middle Allier through the Auvergne. Pool tails, riffle heads, and the seams behind boulders.
Method
Upstream dry to risers; dry-dropper through the riffles. The Allier's clear volcanic water reads every line wrinkle — long leader, fine tippet, careful approach.
Kit
9 ft #4 — French freestone default. Floating line, 12 ft leader to 4 to 5 lb fluoro. Studded boots.
Why this works
Water at 23°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Hatch timeline · todayPeak at 6pm

Hatch predictions

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

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 2 with Pro.

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Evidence
Survey-backed · regionalModerate confidence

Backed by regional invertebrate surveys; no sampling on this exact reach yet.

Updated 15 hours ago

Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
Grayling seasonSeason
1
2
2
2
1
Large Dark OliveHatch
1
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Autumn OliveHatch
1
2
1
GrannomHatch
1
1

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

Ranked for today
Brown Trout fly box

French nymph-first water. Fast current, technical presentation, weighted nymphs and emergers, with dry flies when fish rise.

Permits & access
Permit required — see local rules.
  • AAPPMA permits.
What's coming
Plan ahead
5-day outlook
Cooler water nearby · 1
Probably above the Brown Trout safety line — these are likely cooler, but carry a thermometer.
Gallery · 2
  1. A wide, tree-lined stretch of the River Allier flowing calmly past wooded hillsides in autumn near Coudes, Puy-de-Dôme, France.
    The River Allier at Coudes, Puy-de-Dôme, Auvergne
  2. Terrain map of the venue
    Terrain map
About this water

The Allier is the Loire's great salmon tributary and the most important wild Atlantic salmon river left in mainland France. Every salmon entering the Loire system to spawn in the Auvergne highlands comes up this river. There is no stocking. Every fish is wild, and every fish has run 900 kilometres from the Atlantic. Salmon fishing is closed. The Loire-basin population is a conservation stock, monitored rather than fished. The Poutès dam reconfiguration, completed in 2020, reopened access to critical upstream spawning habitat for the first time in 80 years, and the run, though still small, is showing signs of recovery. The Allier is also first-rate brown trout and grayling water throughout its middle and upper reaches, with strong Baetis and stonefly hatches. The gorge sections above Langeac, where the river cuts through volcanic rock, are particularly good.

  • Granite
Water quality (WFD)
  • EcologyModerate
  • ChemicalUnknown

WFD classification · FRGR0245

The full read · show the working · for Brown Trout · confidence 90%
How the 4 is built — score × weight = contribution
Temperature2 × 28%0.6
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time65 × 13%8.5
Pressure80 × 7%5.6
Insect activity65 × 12%7.8
Limiting factor: Water temperature (23°C) is outside Brown Trout's preferred range (10–16°C)= 57
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
  • Trout 2nd Saturday of March3rd Sunday of September
  • Grayling 3rd Saturday of May3rd Sunday of September

    France national rule: grayling opens 3rd Saturday of May in all waters. In 1st category (salmonid) rivers, grayling closes with the trout season on the 3rd Sunday of September. Departmental regulations may impose additional restrictions. Always check the relevant département's 2026 arrêté préfectoral.

Salmon: Banned (2026) — Salmon fishing prohibited across the Loire basin (long-term ban).

Sea trout: Banned (2026) — Loire basin migratory species ban.

Related guides
Booking & contacts