Freestone · Mixed · Navarra

Río Ulzama

Río Ulzama terrain map
Terrain map

A major Arga tributary flowing from mixed granite-limestone Sierra de Aralar north to Pamplona.

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
  • LevelDry recentlyNo gauge reading
  • Water temp23.2°C
  • ClarityClear
Today’s fly
Klinkhammer
Klinkhammer14-18
High-confidence seasonal pick
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp23.2°C
ClarityClear
Weather32°C
WindS 12 km/h
Pressure1015 hPa
Rain · recent0.0 mm
Rain · ahead0.8 mm

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

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.
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
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.
  • Se requiere licencia de pesca del Gobierno de Navarra
  • El Ulzama es una de las opciones truteras de excursión de un día más sencillas desde Pamplona, pero aún hay que comprobar la lógica exacta del tramo y el permiso antes de viajar.
What's coming
Plan ahead
5-day outlook
Water here around 23°C. Nothing cooler within range — carry a thermometer.
About this water

A major Arga tributary flowing from mixed granite-limestone Sierra de Aralar north to Pamplona. Accessible from the city, offering excellent upper and middle trout water — limestone gorges alternate with open pastoral valleys. Brown trout throughout; trout in lower sections after spates. Fast snowmelt response with consistent summer base flow. Technical nymphing and dry fly in gorges; pool-and-run fishing in valleys. Popular weekend escape from the city.

  • Mixed
Water quality (WFD)
  • Ecology: Good
  • Chemical: Unknown

WFD classification · ES091MSPF544

The full read · show the working · for brown trout · confidence 90%
How the 0 is built — score × weight = contribution
Temperature1 × 28%0.3
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time55 × 13%7.2
Pressure80 × 7%5.6
Insect activity44 × 12%5.3
Limiting factor: Water temperature (23.2°C) is outside Brown Trout's preferred range (10–16°C)= 49
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.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout1 May → 30 June

    RSS Arga–Ultzama basin (922 permits in 2026). All catch-and-release. Extendable to 15 Jul by resolution. Daily basin permit required. Most accessible day-trip trout water from Pamplona.

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Pyrenees PlaybookSpanish riversEuro Nymphingsubsurface methods
Booking & contacts