Freestone · Limestone · Castilla y León, ES

Upper Río Duero

El río Duero, cerca de su nacimiento en Duruelo de la Sierra, Soria
Poor · Brown Trout
Pheasant Tail Nymph · 14-18
Closed season
Out of season. Try elsewhere.
Closed — confidence not applicable today.
What moved it
  • Level0.10 mLast reading 2h ago
  • Water temp7.0°C
  • ClarityClear
Today's fly
Pheasant Tail Nymph
Pheasant Tail Nymph14-18
High-confidence seasonal pick
Conditions on the water
Live gauge
Level
Steady
0.10 m
Last reading 2h ago
Water temp7.0°C
ClarityClear
Weather17°C
WindN 6 km/h
Pressure1026 hPa
Rain · recent0.0 mm
Rain · ahead0.1 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
Cool — slow
7°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.
Likely species
Mayflies
Stoneflies
Gammarids
Hatch timeline · todayPeak at 10:00

Hatch predictions

Today's headline hatch shown — see all 4 active hatches hour by hour as a supporter.

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Sub-surface · on the nymphunder the surface

Hatch predictions

Supporters see the full sub-surface read.

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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 · October highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
1
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1

Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.

Ranked for today
Fly box · Brown Trout
Permits & access
Permit required — see local rules.
  • Se requiere licencia de pesca de Castilla y León
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Río Revinuesa
7.0 km
0
Brown trout
Río Abión
19 km
0
Brown trout
Río Arlanza
26 km
0
Brown trout
Río Ucero
35 km
0
Brown trout
Embalse de la Cuerda del Pozo
3.0 km
Carp · Barbel
Gallery · 2
  1. El río Duero, cerca de su nacimiento en Duruelo de la Sierra, Soria
  2. Terrain map of the venue
    Terrain map
Water quality (WFD)
  • Ecology: Bad
  • Chemical: Unknown
What this classification means

WFD ecological status Moderate → Bad corrected to EEA WISE 2022 (3rd RBMP) classification for waterbody ES020MSPF000000306 (was a stale earlier-cycle value). Source: EEA WISE SWB_SurfaceWaterBody (discodata.eea.europa.eu), verified 2026-06-18.

WFD classification · ES020MSPF000000306

The full read · show the working · for Brown Trout · confidence 75%
How the 0 is built — score × weight = contribution
Temperature49 × 28%13.7
Flow40 × 22%8.8
Clarity95 × 18%17.1
Feeding Time75 × 13%9.8
Pressure80 × 7%5.6
Insect activity28 × 12%3.4
Conditions total= 58
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Warmer water — toward the 10–16 °C ideal band — would lift the temperature score.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout Último Sunday de March → 31 July
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts