Freestone · Granite · Massif Central / Puy-de-Dôme

Sioule

A wooded river gorge with a stone bridge crossing the Sioule river, Puy-de-Dôme, France.

The Sioule flows through volcanic Auvergne terrain where basalt and granite create a river of character — clear, responsive to rainfall, with strong populations of wild brown trout and grayling.

Poor · Brown Trout
Small Perdigón · 16-20
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
  • Flow3.5 m³/sLast reading 8h ago
  • Water temp23.5°C
  • ClarityClear
Today's fly
Small Perdigón
Small Perdigón16-20
Euro-nymph
Conditions on the water
Live gauge
Flow
Steady
3.5 m³/s
Last reading 8h ago
Water temp23.5°C
ClarityClear
Weather34°C
WindNE 7 km/h
Pressure1019 hPa
Rain · recent0.1 mm
Rain · ahead0.0 mm

The nearest gauge doesn't record temperatures, so we've estimated it — defer to the river keeper's advice.

Water temperature for Brown Trout
Warm — slow
24°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the open trout season. Spring olives April through May; sedges through summer evenings; small dark flies into autumn.
Where
Pool tails and pocket water through the Puy-de-Dôme valley. The Sioule runs intimate Auvergne freestone.
Method
Upstream dry to risers; dry-dropper through the riffles. The water reads clear — long leader, fine tippet. Move slowly, cast accurately.
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 23.5°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 5 active hatches hour by hour with Pro.

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Sub-surface · on the nymphunder the surface

Hatch predictions

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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.

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
  • Auvergne regulations.
What's coming
Plan ahead
5-day outlook
Cooler water nearby · 3
Probably above the Brown Trout safety line — these are likely cooler, but carry a thermometer.
Lac Servières
34 km
~20°C
Brown trout
Lac d'Aydat
25 km
~22°C
Brown trout · Pike
Pisciculture du Moulin de la Charme
27 km
~23°C
Rainbow trout · Brown trout · Char
Gallery · 2
  1. A wooded river gorge with a stone bridge crossing the Sioule river, Puy-de-Dôme, France.
    Gorges de la Sioule, Puy-de-Dôme
  2. Terrain map of the venue
    Terrain map
About this water

The Sioule flows through volcanic Auvergne terrain where basalt and granite create a river of character — clear, responsive to rainfall, with strong populations of wild brown trout and grayling. Excellent Baetis, caddis, and stonefly hatches. Multiple tributaries offer variety. Freestone fishing: fast water, pocket trout, responsive to insect activity. Spring through early summer best. Check AAPPMA.

Hatches & food

In freestone rivers of the Massif Central, resident brown trout feed through a spring build-up of olives and stoneflies into a long summer of caddis and small buzzers, with terrestrials becoming important from early summer; higher volcanic plateaux and colder headwaters tend to run later than the lower freestones.

  • Granite
Water quality (WFD)
  • Ecology: Good
  • Chemical: Unknown

WFD classification · FRGR1338

The full read · show the working · for Brown Trout · confidence 90%
How the 0 is built — score × weight = contribution
Temperature0 × 28%0.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time65 × 13%8.5
Pressure80 × 7%5.6
Insect activity48 × 12%5.8
Limiting factor: Water temperature (23.5°C) is outside Brown Trout's preferred range (10–16°C)= 55
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
Apple MapsGoogle Maps
Seasons & zones
  • Trout 2nd Saturday of March → 3rd Sunday of September
  • Grayling 3rd Saturday of May → 3rd 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.

Related guides
Grayling Playbookgrayling tacticsPyrenees PlaybookFrench riversEuro Nymphingsubsurface methods
Booking & contacts