- Ecology: Moderate
- Chemical: Unknown
WFD classification · FRHR166
Rules at a glance
- Day tickets
Water temperature for Brown Trout
Warm — slow23°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the open trout season. Iron Blue and CDC grannom in April; olives through May; sedges through summer evenings.
Where
Pool tails and weeded glides through the chalk-stream stretches around Dieppe. The Arques is intimate water; read each lie.
Method
Upstream dry to spotted rising fish; long fine leader. The water reads clear — careful approach matters more than fly choice. Move slowly upstream, cast accurately, accept the result.
Kit
9 ft #4 — French karst-stream default. Floating line, 14 ft leader to 4 lb fluoro. Polarising glasses non-negotiable.
Why this works
Water at 23.2°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 6 active hatches hour by hour with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 2 with Pro.
Start free trial14-day free trial. Cancel anytime.
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
Sea trout runRun
1
2
2
2
2
2
1
Trout seasonSeason
1
2
2
2
2
2
1
Grayling seasonSeason
1
2
2
2
2
2
2
1
Brown SedgeHatch
2
3
2
Freshwater ShrimpHatch
2
3
3
3
3
3
3
3
3
3
3
2
Blue Winged OliveHatch
2
3
3
3
3
2
Mayfly (Green Drake)Hatch
2
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
Permits & access
Permit required — see local rules.
- AAPPMA permits
- Private estate water on sections.
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.
Water quality (WFD)
The full read · show the working · for Brown Trout · confidence 90%
How the 2 is built — score × weight = contribution
Temperature1 × 28%0.3
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time60 × 13%7.8
Pressure80 × 7%5.6
Insect activity44 × 12%5.3
Limiting factor: Water temperature (23.2°C) is outside Brown Trout's preferred range (10–16°C)= 54
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
- Sea trout 25 April → 25 October
- Trout 2nd Saturday of March → 3rd Sunday of September
- Grayling 3rd Saturday of May → 31 December
France national rule: grayling opens 3rd Saturday of May in all waters. In 2nd category waters, grayling remains open until 31 December. Departmental regulations may impose earlier closing dates. Always check the relevant département's 2026 arrêté préfectoral.
Sea trout: Open (2026) — Credible secondary sea trout river. 28 declared rod catches in 2024 — better than many historic glamour rivers.
Related guides
Booking & contacts
Arques
Water temperature for Brown Trout
Warm — slow23°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the open trout season. Iron Blue and CDC grannom in April; olives through May; sedges through summer evenings.
Where
Pool tails and weeded glides through the chalk-stream stretches around Dieppe. The Arques is intimate water; read each lie.
Method
Upstream dry to spotted rising fish; long fine leader. The water reads clear — careful approach matters more than fly choice. Move slowly upstream, cast accurately, accept the result.
Kit
9 ft #4 — French karst-stream default. Floating line, 14 ft leader to 4 lb fluoro. Polarising glasses non-negotiable.
Why this works
Water at 23.2°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 6 active hatches hour by hour with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 2 with Pro.
Start free trial14-day free trial. Cancel anytime.
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
Sea trout runRun
1
2
2
2
2
2
1
Trout seasonSeason
1
2
2
2
2
2
1
Grayling seasonSeason
1
2
2
2
2
2
2
1
Brown SedgeHatch
2
3
2
Freshwater ShrimpHatch
2
3
3
3
3
3
3
3
3
3
3
2
Blue Winged OliveHatch
2
3
3
3
3
2
Mayfly (Green Drake)Hatch
2
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
Permits & access
Permit required — see local rules.
- AAPPMA permits
- Private estate water on sections.
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.
Water quality (WFD)
- Ecology: Moderate
- Chemical: Unknown
WFD classification · FRHR166
The full read · show the working · for Brown Trout · confidence 90%
How the 2 is built — score × weight = contribution
Temperature1 × 28%0.3
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time60 × 13%7.8
Pressure80 × 7%5.6
Insect activity44 × 12%5.3
Limiting factor: Water temperature (23.2°C) is outside Brown Trout's preferred range (10–16°C)= 54
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
- Sea trout 25 April → 25 October
- Trout 2nd Saturday of March → 3rd Sunday of September
- Grayling 3rd Saturday of May → 31 December
France national rule: grayling opens 3rd Saturday of May in all waters. In 2nd category waters, grayling remains open until 31 December. Departmental regulations may impose earlier closing dates. Always check the relevant département's 2026 arrêté préfectoral.
Sea trout: Open (2026) — Credible secondary sea trout river. 28 declared rod catches in 2024 — better than many historic glamour rivers.
Related guides
Booking & contacts