Karst Spring · Limestone · Cantabria (Trasmiera / Entrambasaguas), ES

Río Aguanaz

Río Aguanaz — M-fuente-del-frances-hoznayo-abrio-2021-a
Contributor photo

M-fuente-del-frances-hoznayo-abrio-2021-a

MottaW - CC BY

A short Trasmiera tributary of the Miera, rising near Entrambasaguas and joining the parent river above the estuary.

Marginal · Brown Trout
Klinkhammer · 14-18
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
  • Level0.07 mLast reading 20h ago
  • Water temp19.7°C
  • ClarityClear
Today’s fly
Klinkhammer
Klinkhammer14-18
High-confidence seasonal pick
Conditions on the water
Live gauge
Level
Steady
0.07 m
lowspate
Water temp19.7°C
ClarityClear
Weather22°C
WindE 5 km/h
Pressure1017 hPa
Rain · recent0.0 mm
Rain · ahead2.9 mm

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

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. Otherwise poor — water clarity is in the right range.
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

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
Brown SedgeHatch
2
3
2
Freshwater ShrimpHatch
2
3
3
3
3
3
3
3
3
3
3
2
Blue Winged OliveHatch
2
3
3
3
3
2
Mayfly (Green Drake)Hatch
2
2

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.
  • Se requiere licencia de pesca cántabra.
What's coming
Plan ahead
5-day outlook
Water here around 20°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
  1. Río Aguanaz — M-fuente-del-frances-hoznayo-abrio-2021-a
    M-fuente-del-frances-hoznayo-abrio-2021-a
  2. Terrain map of the venue
    Terrain map
About this water

A short Trasmiera tributary of the Miera, rising near Entrambasaguas and joining the parent river above the estuary. Limestone-influenced spring-fed water — clearer and steadier than the typical spate-fed Cantabrian small river, with karst character through the middle reaches above Entrambasaguas. Wild brown trout only. Best fished from late April through June.

  • Limestone
The full read · show the working · for brown trout · confidence 80%
How the 29 is built — score × weight = contribution
Temperature29 × 28%8.1
Flow15 × 22%3.3
Clarity95 × 18%17.1
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity23 × 12%2.8
Limiting factor: River is stable — Brown Trout prefers medium flow= 47
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
  • Troutthird Sunday of March → 31 July
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts