Freestone · Slate · Castilla y León

Río Sil

Río Sil — Cañon del Río Sil desde el mirador de Vilouxe
Contributor photo

Cañon del Río Sil desde el mirador de Vilouxe

Fernando (https://commons.wikimedia.org/wiki/User:Fernando) - CC BY-SA

The Sil dominates the El Bierzo landscape — 80 km of slate-based freestone with outstanding productivity.

Poor · Brown Trout
Klinkhammer · 14-18
Poorlive now
Not the day for it
River temperature is the limiting factor today, not the flow. This is not the day to push it. Check the thermal advice above before you head out.
90% confidence
What moved it
  • Level0.26 mDropping after lift
  • Water temp22.7°C
  • ClarityUnfishableColouring up
Today’s fly
Klinkhammer
Klinkhammer14-18
High-confidence seasonal pick
Conditions on the water
Live gauge
Level
Steady
0.26 m
Dropping after lift
Water temp22.7°C
ClarityUnfishable
Weather28°C
WindW 13 km/h
Pressure1014 hPa
Rain · recent0.0 mm
Rain · ahead2.6 mm

Live readings — water temperature is an estimate where the gauge does not record it.

Water temperature for brown trout
Warm — slow
23°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 22.7°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Sub-surface · on the nymphunder the surface

Hatch predictions

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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
Records-basedModerate confidence

Based on species-occurrence records, not local invertebrate surveys.

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
1
Large Dark OliveHatch
1
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Autumn OliveHatch
1
2
1
GrannomHatch
1
1

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.
  • Castilla y León fishing licence required
  • Many premium trout waters use the Junta's tramo-based management system, including EDE sections, so check the exact section and current rules before travel.
What's coming
Plan ahead
5-day outlook
Cooler water nearby · 2
Probably above the brown trout safety line — these are likely cooler, but carry a thermometer.
Río Cabrera
31 km
~13°C
Brown trout
Río Burbia
21 km
~15°C
Brown trout
Gallery · 2
  1. Río Sil — Cañon del Río Sil desde el mirador de Vilouxe
    Cañon del Río Sil desde el mirador de Vilouxe
  2. Terrain map of the venue
    Terrain map
About this water

The Sil dominates the El Bierzo landscape — 80 km of slate-based freestone with outstanding productivity. Large wild brown populations thrive on slate geology and consistent base flows. Dramatic gorges and productive pools create varied habitat: technical upper reaches with selective fish to larger holding water downstream. Strong mayfly hatches throughout season and 8-hour response time make this a premier fly-fishing destination.

  • Slate
Water quality (WFD)
  • Ecology: Bad
  • Chemical: Unknown
What this classification means

WFD ecological status Poor → Bad corrected to EEA WISE 2022 (3rd RBMP) classification for waterbody ES010MSPFES425MAR000880 (was a stale earlier-cycle value). Source: EEA WISE SWB_SurfaceWaterBody (discodata.eea.europa.eu), verified 2026-06-18.

WFD classification · ES010MSPFES425MAR000880

The full read · show the working · for brown trout · confidence 90%
How the 0 is built — score × weight = contribution
Temperature3 × 28%0.8
Flow80 × 22%17.6
Clarity0 × 18%0.0
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity48 × 12%5.8
Limiting factor: Water is unfishable — too coloured for Brown Trout= 40
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.
A drop and clear would lift the flow and clarity scores.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • TroutLast Sunday of March → 31 July
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts