Stoneflies
Caddisflies
Damselflies & dragonflies
Gammarids
Flows through the Fiemme and Fassa valleys framed by beautiful alpine scenery. Brown trout and marble trout in the water, with some sections regulated by hydro releases. Good dry fly fishing during caddis hatches when the light is right.
- Mixed
Rules at a glance
- Licence required
Water temperature for Brown Trout
Ideal11°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. Val di Fiemme and Val di Fassa fish high-elevation cold water.
Where
Pool tails, riffle heads, and the seams through the dolomite gorges. The Avisio runs cleaner pocket water than the glacial Sarca and Noce.
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
Excellent — water temperature is right today, though time of day could be better.
Likely species
Caddisflies
- Net-spinning caddisMost likelyLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- CapererAlso possibleLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
- Green SedgeAlso possibleLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- Welshman's ButtonAlso possibleLower confidence#12–14 · Egg-layingSkitter it at dusk — this one's fished, not dead-drifted.
Damselflies & dragonflies
Hatch timeline · todayPeak at 12pm
Hatch predictions
Today's headline hatch shown — see all 12 active hatches hour by hour as a supporter.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Supporters see the full sub-surface read.
Start free trial14-day free trial. Cancel anytime.
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
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
A fuller Italian trout and grayling box for the southern Alps and northern limestone/alpine systems. It keeps the marble-trout streamer accent, but adds proper grayling dries and bugs, competition nymphs, caddis/olive work, terrestrials, pocket-water dries and alpine lake patterns.
18-22 · Pattern
Upstream dry, in the film
Permits & access
Permit required — see local rules.
- Italian fishing license (permesso di pesca) varies by provincia (province)
- Barbless hooks often required on protected waters
- Catch limits may apply.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
The Avisio river just south of Cavalese, Val di Fiemme Terrain map
About this water
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
WFD classification · ITARW02AD07200060TN
The full read · show the working · for Brown Trout · confidence 75%
How the 81 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time45 × 13%5.9
Pressure80 × 7%5.6
Insect activity53 × 12%6.4
Conditions total= 81
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 2026-02-15 → 2026-10-07
- Marble trout 2026-03-01 → 2026-09-30
Related guides
Booking & contacts
Avisio
Flows through the Fiemme and Fassa valleys framed by beautiful alpine scenery.
Water temperature for Brown Trout
Ideal11°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. Val di Fiemme and Val di Fassa fish high-elevation cold water.
Where
Pool tails, riffle heads, and the seams through the dolomite gorges. The Avisio runs cleaner pocket water than the glacial Sarca and Noce.
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
Excellent — water temperature is right today, though time of day could be better.
Likely species
Caddisflies
- Net-spinning caddisMost likelyLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- CapererAlso possibleLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
- Green SedgeAlso possibleLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- Welshman's ButtonAlso possibleLower confidence#12–14 · Egg-layingSkitter it at dusk — this one's fished, not dead-drifted.
Damselflies & dragonflies
Hatch timeline · todayPeak at 12pm
Hatch predictions
Today's headline hatch shown — see all 12 active hatches hour by hour as a supporter.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Supporters see the full sub-surface read.
Start free trial14-day free trial. Cancel anytime.
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
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
A fuller Italian trout and grayling box for the southern Alps and northern limestone/alpine systems. It keeps the marble-trout streamer accent, but adds proper grayling dries and bugs, competition nymphs, caddis/olive work, terrestrials, pocket-water dries and alpine lake patterns.
18-22 · Pattern
Upstream dry, in the film
Permits & access
Permit required — see local rules.
- Italian fishing license (permesso di pesca) varies by provincia (province)
- Barbless hooks often required on protected waters
- Catch limits may apply.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
The Avisio river just south of Cavalese, Val di Fiemme Terrain map
About this water
Flows through the Fiemme and Fassa valleys framed by beautiful alpine scenery. Brown trout and marble trout in the water, with some sections regulated by hydro releases. Good dry fly fishing during caddis hatches when the light is right.
- Mixed
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
WFD classification · ITARW02AD07200060TN
The full read · show the working · for Brown Trout · confidence 75%
How the 81 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time45 × 13%5.9
Pressure80 × 7%5.6
Insect activity53 × 12%6.4
Conditions total= 81
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 2026-02-15 → 2026-10-07
- Marble trout 2026-03-01 → 2026-09-30
Related guides
Booking & contacts