Freestone · Limestone · Castilla y León

Río Carrión

Río Carrión — Velilla desde Compuerto

The Carrión flows through limestone uplands creating a classic freestone river — clear water and consistent insect productivity supporting unusually large brown trout (many exceeding three pounds).

Poor · Brown Trout
Klinkhammer · 14-18
Closed season
Out of season. Plenty of other water available now.
Closed — confidence not applicable today.
What moved it
  • Level0.04 mLast reading 22 min ago
  • Water temp22.4°C
  • ClarityClear
Today's fly
Klinkhammer
Klinkhammer14-18
High-confidence seasonal pick
Conditions on the water
Live gauge
Level
Steady
0.04 m
Last reading 22 min ago
Water temp22.4°C
ClarityClear
Weather30°C
WindE 17 km/h
Pressure1016 hPa
Rain · recent0.0 mm
Rain · ahead2.5 mm

The nearest gauge doesn't record temperatures, so we've estimated it — defer to the river keeper's advice.

Water temperature for Brown Trout
Warm — slow
22°C est.ideal 10–16°C
0°14°28°
How to fish it · for Brown Trout
When
Through the Castilla y León trout season. Spring olives April through May; summer evenings; small dark flies into autumn close.
Where
Pool tails and the seams behind boulders through the Palencia valley. The Carrión runs cool Cantabrian-fed water through the upper beats.
Method
Upstream dry to risers; dry-dropper through the riffles. The water reads clear — long leader, fine tippet, careful approach.
Kit
9 ft #4 — Castilian default. Floating line, 12 ft leader to 4 lb fluoro. Studded boots — granite cobble runs slick.
Why this works
Water at 22.4°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Hatch timeline · todayPeak at 6am

Hatch predictions

Today's headline hatch shown — see all 4 active hatches hour by hour with Pro.

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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

Top prey shown — see all 2 with Pro.

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Evidence
Survey-backed · regionalHigh confidence

Backed by regional invertebrate surveys; no sampling on this exact reach 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
1
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
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
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
  1. Río Carrión — Velilla desde Compuerto
    Velilla desde Compuerto
  2. Terrain map of the venue
    Terrain map
About this water

The Carrión flows through limestone uplands creating a classic freestone river — clear water and consistent insect productivity supporting unusually large brown trout (many exceeding three pounds). Designated Coto Intensivo sections near Guardo enforce selective management and fly-only regulations protecting these fish. Stable limestone hatches (Baetis rhodani, Ephemerella notata, small olives) run April–July. A river where size and quality reward careful presentation.

  • Limestone
Water quality (WFD)
  • Ecology: Poor
  • Chemical: Unknown
What this classification means

WFD ecological status Moderate → Poor corrected to EEA WISE 2022 (3rd RBMP) classification for waterbody ES020MSPF000000130 (was a stale earlier-cycle value). Source: EEA WISE SWB_SurfaceWaterBody (discodata.eea.europa.eu), verified 2026-06-18.

WFD classification · ES020MSPF000000130

The full read · show the working · for Brown Trout · confidence 90%
How the 0 is built — score × weight = contribution
Temperature4 × 28%1.1
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time60 × 13%7.8
Pressure80 × 7%5.6
Insect activity59 × 12%7.1
Limiting factor: Water temperature (22.4°C) is outside Brown Trout's preferred range (10–16°C)= 56
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout Last Sunday of March → 31 July
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts