Freestone · Limestone · Primorska / Tolmin

River Trebuščica

A clear stream cascading over limestone slabs beneath a stone arch bridge in the Srna gorge, Gorenja Trebuša.

The lower Trebuščica is a small limestone tributary running into the Soča, and one of the quiet places in RD Tolmin's water — the kind of stream you fish because you want to, not because someone told you it was good.

Marginal · Brown Trout
Elk Hair Caddis · 12-16
Marginallive now
Slow going — pick your moments
River temperature is the limiting factor today, not the flow. Fish dawn or dusk if you go at all, and handle everything with extra care.
80% confidence
What moved it
  • LevelDry recentlyNo gauge reading
  • Water temp19.7°C
  • ClarityClear
Today's fly
Elk Hair Caddis
Elk Hair Caddis12-16
High-confidence seasonal pick
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp19.7°C
ClarityClear
Weather23°C
WindE 17 km/h
Pressure1022 hPa
Rain · recent0.0 mm
Rain · ahead0.0 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Water temperature for Brown Trout
Warm — slow
20°C est.ideal 10–16°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 19.7°C — above the brown trout caution line (18°C). Fish dawn or dusk only. Land it fast, wet hands, no air shots.
Hatch timeline · todayPeak at 5pm

Hatch predictions

Today's headline hatch shown — see all 11 active hatches hour by hour with Pro.

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Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 2 guilds 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
ModelledModerate confidence

Modelled from regional ecology — no survey or occurrence data for this water 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
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

Ultra-clear spring-fed rivers with large educated trout. Sight fishing, technical presentation, fine tippets. Euro-nymphing dominant subsurface method. Exceptional dry-fly windows during hatch periods. Gacka is the flagship water.

Permits & access
Permit required — see local rules.
  • Fishing licence + permit.
What's coming
Plan ahead
5-day outlook
Water here around 20°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
  1. A clear stream cascading over limestone slabs beneath a stone arch bridge in the Srna gorge, Gorenja Trebuša.
    Srna gorge stream, Trebuščica valley
  2. Terrain map of the venue
    Terrain map
About this water

The lower Trebuščica is a small limestone tributary running into the Soča, and one of the quiet places in RD Tolmin's water — the kind of stream you fish because you want to, not because someone told you it was good. It carries genuine marble trout, which is the whole point: the upper 5.7 km above the fishable water is a breeding reserve, permanently closed, and that closure is the reason the fish below it are worth catching at all. Season runs 1 March to 20 October — earlier than most of the district, so don't assume the October dates that apply on the Soča apply here too. Barbless, C&R, and quiet feet.

  • River
  • Limestone
Water quality (WFD)
  • Ecology: Good
  • Chemical: Unknown
The full read · show the working · for Brown Trout · confidence 80%
How the 29 is built — score × weight = contribution
Temperature29 × 28%8.1
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity65 × 12%7.8
Conditions total= 67
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout 1 March → 20 October
  • Marble trout 1 April → 20 October
Related guides
Alpine Streamsmountain entomologyMarble TroutSoča systemEuro Nymphingsubsurface methods
Booking & contacts