Mayflies
Stoneflies
Caddisflies
Gammarids
- Ecology: Good
- Chemical: Unknown
WFD classification · IT0101SS3N721PI
Rules at a glance
- Licence required
Water temperature for Brown Trout
Ideal13°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the Italian trout season — afternoon hatches in spring; dawn and dusk in summer warm. The Sesia is glacial-influenced from Monte Rosa.
Where
Pool tails and the deeper edges of pockets. The middle Sesia through the Valsesia is classic Italian Alpine pocket water.
Method
Upstream nymph through the broken water; dry to risers in the glides. Italian No-Kill stretches mandate single barbless — comply or fish elsewhere.
Kit
9 to 10 ft #4 for medium freestone with Alpine clarity. Floating line, 12 ft leader to 4 to 5 lb fluoro. Studded boots — Alpine cobble runs slick.
Why this works
Poor — water temperature is working for you, but river flow is the limiting factor today.
Likely species
Caddisflies
- Net-spinning caddisMost likelyLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- Green SedgeAlso possibleLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- CapererAlso possibleLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
Hatch timeline · tomorrowPeak at 14h
12h(now) — Reed Smut
Stage: On emergersApproach: Emerger or dryActivity: 56%
Also:Heather Fly54%Cinnamon Sedge52%Autumn Olive52%
Peak emergence windowWeather boost11 food groups active
Peak activity at 14h — Autumn Dun (Autumn Dun, Weather boost)
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Top prey shown — see all 2 as a supporter.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalHigh confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Freshwater ShrimpHatch
2
3
3
3
3
3
3
3
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Autumn OliveHatch
1
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Brown Trout
18-22 · Pattern
Upstream dry, in the film
Permits & access
Permit required — see local rules.
- Permesso di pesca varies by provincia
- Always check local regulations.
What's coming
Plan ahead
5-day outlook
Other water nearby · 3
Gallery · 2
Terrain map
Water quality (WFD)
The full read · show the working · for Brown Trout · confidence 55%
How the 30 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow15 × 22%3.3
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity42 × 12%5.0
Limiting factor: River is stable — Brown Trout prefers medium flow= 68
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
A drop and clear would lift the flow and clarity scores.
Directions
Seasons & zones
- Trout 2026-03-01 → 2026-09-30
- Marble trout 2026-03-01 → 2026-09-30
Related guides
Booking & contacts
Permits & access
- SVPS / Valsesia Pesca — Sesia and Valsesia permitsPrimary public permit route for the Sesia system managed by the Società Valsesiana Pescatori Sportivi, including day, fortnightly and annual permits plus tourist reserves.
- Regione Piemonte — Fishing licenceRegional recreational fishing licence route for Piedmont. Use before or alongside local reserve permits where required.
Sesia
Water temperature for Brown Trout
Ideal13°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the Italian trout season — afternoon hatches in spring; dawn and dusk in summer warm. The Sesia is glacial-influenced from Monte Rosa.
Where
Pool tails and the deeper edges of pockets. The middle Sesia through the Valsesia is classic Italian Alpine pocket water.
Method
Upstream nymph through the broken water; dry to risers in the glides. Italian No-Kill stretches mandate single barbless — comply or fish elsewhere.
Kit
9 to 10 ft #4 for medium freestone with Alpine clarity. Floating line, 12 ft leader to 4 to 5 lb fluoro. Studded boots — Alpine cobble runs slick.
Why this works
Poor — water temperature is working for you, but river flow is the limiting factor today.
Likely species
Caddisflies
- Net-spinning caddisMost likelyLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- Green SedgeAlso possibleLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- CapererAlso possibleLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
Hatch timeline · tomorrowPeak at 14h
12h(now) — Reed Smut
Stage: On emergersApproach: Emerger or dryActivity: 56%
Also:Heather Fly54%Cinnamon Sedge52%Autumn Olive52%
Peak emergence windowWeather boost11 food groups active
Peak activity at 14h — Autumn Dun (Autumn Dun, Weather boost)
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Top prey shown — see all 2 as a supporter.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalHigh confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Freshwater ShrimpHatch
2
3
3
3
3
3
3
3
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Autumn OliveHatch
1
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Brown Trout
18-22 · Pattern
Upstream dry, in the film
Permits & access
Permit required — see local rules.
- Permesso di pesca varies by provincia
- Always check local regulations.
What's coming
Plan ahead
5-day outlook
Other water nearby · 3
Gallery · 2
Terrain map
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
WFD classification · IT0101SS3N721PI
The full read · show the working · for Brown Trout · confidence 55%
How the 30 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow15 × 22%3.3
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity42 × 12%5.0
Limiting factor: River is stable — Brown Trout prefers medium flow= 68
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
A drop and clear would lift the flow and clarity scores.
Directions
Seasons & zones
- Trout 2026-03-01 → 2026-09-30
- Marble trout 2026-03-01 → 2026-09-30
Related guides
Booking & contacts
Permits & access
- SVPS / Valsesia Pesca — Sesia and Valsesia permitsPrimary public permit route for the Sesia system managed by the Società Valsesiana Pescatori Sportivi, including day, fortnightly and annual permits plus tourist reserves.
- Regione Piemonte — Fishing licenceRegional recreational fishing licence route for Piedmont. Use before or alongside local reserve permits where required.