Karst Spring · Limestone · Castilla y León

Río Omecillo

Río Omecillo — Bergüenda01
Contributor photo

Bergüenda01

Toño Antón (https://commons.wikimedia.org/wiki/User:AntonVe) - CC BY-SA

A cross-border Ebro tributary on the Burgos-Álava boundary, joining the Ebro near Bergüenda.

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
  • LevelDry recentlyNo gauge reading
  • Water temp19.0°C
  • ClarityClear
Today’s fly
Klinkhammer
Klinkhammer14-18
High-confidence seasonal pick
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp19.0°C
ClarityClear
Weather21°C
WindE 5 km/h
Pressure1018 hPa
Rain · recent0.0 mm
Rain · ahead0.9 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Water temperature for brown trout
Warm — slow
19°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°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

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

See the full sub-surface read with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 3 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.
  • Licencia de Castilla y León (Burgos); verifica los tramos limítrofes con Álava por si existen normas transfronterizas cerca de la estación de aforo de Bergüenda.
What's coming
Plan ahead
5-day outlook
Water here around 19°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
  1. Río Omecillo — Bergüenda01
    Bergüenda01
  2. Terrain map of the venue
    Terrain map
About this water

A cross-border Ebro tributary on the Burgos-Álava boundary, joining the Ebro near Bergüenda. The Omecillo is karst-influenced trout water — limestone clarity, steady flows, characteristic Álava-Burgos pool-and-riffle structure. The gauge sits in Álava but the river is mostly Burgos. Wild brown trout. Best fished from May through July; the middle reaches around Quintana-Martín Galíndez hold the most accessible water.

  • Limestone
The full read · show the working · for brown trout · confidence 80%
How the 34 is built — score × weight = contribution
Temperature39 × 28%10.9
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time75 × 13%9.8
Pressure80 × 7%5.6
Insect activity61 × 12%7.3
Conditions total= 64
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.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • TroutLast Sunday of March → 31 July
Related guides
Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts