Freestone · Limestone · Primorska / Idrija

Kanomljica

Kanomljica terrain map
Poor · Grayling
F-fly · sizes_14_18
Temporary closure · troutReported 31 Jul 2026

Total fishing suspension in force (low water / high temperature)

RD Idrija had a total suspension of fishing in force as of 31 July 2026 for low water and high water temperature, alongside a national low-water welfare warning live on ribiskekarte.si. This is a biophysical do-not-fish state, not a routine seasonal closure — check RD Idrija's current notice before travelling.

RD Idrija club announcements ↗

Temporary notices from official orders and recent fishery reports — they clear automatically once out of date. Always confirm locally before travelling.

Not the day for it
River dropping into shape after a lift. Not much stacked in your favour today. Worth an hour if you are nearby, not worth the special trip.
45% confidence
limited data
What moved it
  • LevelProxyvia Idrijca
  • Water temp10.8°C
  • ClarityUnfishableColouring up
Today's fly
F-fly
F-flysizes_14_18
off-peak month · matches water height · regional default
Conditions on the water
Proxy gauge
Level
Falling
Proxy
via Idrijca
Water temp10.8°C
ClarityUnfishable
Weather17°C
WindNE 8 km/h
Pressure1023 hPa
Rain · recent0.0 mm
Rain · ahead0.0 mm

No gauge on this water — conditions are inferred from Idrijca. The trend transfers, the absolute level does not.

Water temperature for Grayling
Ideal
11°C est.ideal 4–14°C
0°14°28°
How to fish it · for Grayling
When
Midday window — grayling feed best from late morning into early afternoon.
Where
Work runs and glides — grayling shoal in the bottom third of the water column.
Method
Tight-line nymph the bottom third with weighted patterns.
Kit
10 ft #3 rod, floating line, long leader to 4 lb fluoro for nymphs.
Why this works
Poor — water temperature is working for you, but time of day is the limiting factor today.
Likely species
Mayflies
  • Iron BlueMost likely
    #16–18 · Dun
    Cold, grey day — the dun sits long. Good dry-fly water.
  • Large dark oliveAlso possible
    #14–16 · Emerger
    Dead-drift the emerger — it's sitting in the film.
  • Blue-winged oliveAlso possible
    #16–18 · Dun
    Duns are up; a sherry spinner fall may follow.
Caddisflies
  • GrannomMost likely
    #14–16 · Pupa
    Pupa first, then dries as the adults come off.
  • Net-spinning caddis (S. Europe)Also possibleLower confidence
    #12–14–16 · Pupa
    Widespread riffle net-spinner; evening emergence.
Hatch timeline · todayQuiet day

Hatch predictions

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Sub-surface · on the nymphunder the surface

Hatch predictions

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Beyond the hatch · worth watchingambient prey

Hatch predictions

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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
1
Grayling seasonSeason
1
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
Grayling fly box
Permits & access
Permit required — see local rules.
  • RD Idrija
  • Fly-only, barbless.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Cerknica (Idrijca tributary)
2.0 km
Marble trout · Marble brown hybrid trout · Brown trout
Idrijca
6.0 km
Brown trout · Marble trout · Grayling
Hubelj
16 km
Marble trout · Marble brown hybrid trout · Brown trout
Kneža
16 km
Marble trout · Brown trout · Grayling
Vipava
18 km
Marble trout · Marble brown hybrid trout · Brown trout
The full read · show the working · for Grayling · confidence 45%
How the 20 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity10 × 18%1.8
Feeding Time10 × 13%1.3
Pressure80 × 7%5.6
Insect activity29 × 12%3.5
Limiting factor: Water is unfishable — too coloured for Grayling= 58
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via Idrijcaproxy
Prey activitymodelled from regional profilemodelled
What would change the calculation
A drop and clear would lift the flow and clarity scores.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout 1 March → 30 September
  • Grayling 16 May → 30 November

    Slovenian common default: grayling 16 May – 30 November (lipan). Permit and fishing district controlled — dates may vary by specific water. Always check the Ribiška Družina (fishing district) permit for the specific beat.

    Prime sport 1 September → 30 November

  • Marble trout 1 April → 31 October
Related guides
Grayling Playbookgrayling tacticsAlpine Streamsmountain entomologyMarble TroutSoča system
Booking & contacts