Freestone · Limestone · Haute-Provence

Bès

Bès — Le Bès

The Bès is a small Jurassic-limestone river in the Alpes-de-Haute-Provence that rises in the Trois-Évêchés massif and runs south to join the Bléone just above Digne.

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
  • LevelProxyvia Arc (Bessans reach)
  • Water temp22.5°C
  • ClarityClear
Today's fly
Small Perdigón
Small Perdigón16-20
Euro-nymph
Conditions on the water
Proxy gauge
Level
Steady
Proxy
via Arc (Bessans reach)
Water temp22.5°C
ClarityClear
Weather30°C
WindSW 10 km/h
Pressure1023 hPa
Rain · recent0.0 mm
Rain · ahead5.9 mm

No gauge on this water — conditions are inferred from Arc (Bessans reach). The trend transfers, the absolute level does not.

Water temperature for Brown Trout
Warm — slow
23°C est.ideal 1016°C
0°14°28°
How to fish it · for Brown 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
Water at 22.5°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Hatch timeline · todayPeak at 6am

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

See the full sub-surface read 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.

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
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
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 Alpes-de-Haute-Provence
  • Standard 1ère catégorie.
What's coming
Plan ahead
5-day outlook
Water here around 23°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
  1. Bès — Le Bès
    Le Bès
  2. Terrain map of the venue
    Terrain map
About this water

The Bès is a small Jurassic-limestone river in the Alpes-de-Haute-Provence that rises in the Trois-Évêchés massif and runs south to join the Bléone just above Digne. Most people driving through the area are heading somewhere else — Digne itself is a quiet spa town, the main Provence tourist routes are further south. The Bès is therefore that rare thing: a perfectly good French wild-trout river that hardly anyone bothers to fish. It is textbook limestone water — clear, cold, aquifer-buffered, the flow steady all summer when the schist rivers of the Cévennes are in August retreat. The fish are modest in size but confident and well-fed; the limestone geology produces reliable caddis and Baetis hatches through the whole season. Stalking water more than anything else. Walk upstream, watch the pool tails, and wait for a fish to show. The best beats are in the middle Bès above the Clues de Barles, where the river runs through a narrow limestone valley that holds the water cool even in July.

  • Limestone
Water quality (WFD)
  • EcologyGood
  • ChemicalUnknown

WFD classification · FRDR277A

The full read · show the working · for Brown Trout · confidence 90%
How the 8 is built — score × weight = contribution
Temperature4 × 28%1.1
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time65 × 13%8.5
Pressure80 × 7%5.6
Insect activity55 × 12%6.6
Limiting factor: Water temperature (22.5°C) is outside Brown Trout's preferred range (10–16°C)= 57
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via Arc (Bessans reach)proxy
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
Related guides
Booking & contacts