Freestone · Mixed · Alps / Savoie

Isère (Combe de Savoie)

A wide alpine river flowing past tree-lined banks, with misty mountains in the background near Montmelian, Savoie.

The Isère in Combe de Savoie is big alpine water — 1st-category from Pont Royal to Pontcharra.

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

Severe drought restrictions (alerte renforcée) in force

The Combe de Savoie - Val Gelon zone (Dept 73) 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°37592 ↗

Temporary notices from official orders and recent fishery reports — they clear automatically once out of date.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
  • Level1.20 mLast reading 10h ago
  • Water temp22.5°C
  • ClarityVery colouredColouring up
Today's fly
Small Perdigón
Small Perdigón16-20
Euro-nymph
Conditions on the water
Live gauge
Level
Rising
1.20 m
Last reading 10h ago
Water temp22.5°C
ClarityVery coloured
Weather27°C
WindNE 2 km/h
Pressure1017 hPa
Rain · recent11.5 mm
Rain · ahead1.0 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
23°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the open trout season. Late spring once snowmelt drops; sedges through summer; small dark flies into autumn close.
Where
Pool tails and the seams behind boulders through the Combe de Savoie. The Isère is bigger water than most Alpine tributaries — wadeable but demanding.
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 22.5°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Hatch timeline · todayQuiet day

Hatch predictions

Today's headline hatch shown — see all 2 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
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
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 · 2
Probably above the Brown Trout safety line — these are likely cooler, but carry a thermometer.
Guiers
21 km
~19°C
Brown trout · Grayling
Lac d'Annecy
34 km
~22°C
Brown trout · Char
Gallery · 2
  1. A wide alpine river flowing past tree-lined banks, with misty mountains in the background near Montmelian, Savoie.
    Isere @ Pont Morens @ Montmelian
  2. Terrain map of the venue
    Terrain map
About this water

The Isère in Combe de Savoie is big alpine water — 1st-category from Pont Royal to Pontcharra. Snowmelt character with improving conditions as summer progresses and water clears. Technical at high water, more accessible as levels drop. Fly-fishing opportunity. Check Savoie regulations for access and restrictions.

Hatches & food

In true Alpine headwaters, trout feeding is squeezed into a short high-summer slot, with mountain olives and other mayflies following snowmelt, daytime stoneflies over rough, bouldery water, evening caddis on the warmest settled nights, and small buzzers keeping fish interested before, between and after the main up-wing and caddis hatches.

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

WFD classification · FRDR527A

The full read · show the working · for Brown Trout · confidence 90%
How the 8 is built — score × weight = contribution
Temperature4 × 28%1.1
Flow55 × 22%12.1
Clarity15 × 18%2.7
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity51 × 12%6.1
Limiting factor: Water temperature (22.5°C) is outside Brown Trout's preferred range (10–16°C)= 38
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.
A drop and clear would lift the flow and clarity scores.
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