Mountain Freestone · Volcanic · Honshū

Azusa River (Kamikōchi)

Kamikōchi venue image
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The Azusa rises at the heart of the Japanese Alps at Kamikōchi, a valley of such beauty that it is protected and walked by thousands, and through it the river runs gin-clear over pale stones beneath the Hotaka peaks.

Species

About as good as it gets

Low and clear — careful approach country. Take your time — read the water before you cast.

The water temperature is around 12°C, about where the trout want it, sitting at a steady height, running clear.

90% confidence in this read
Water temperature for brown trout
Ideal
12°C est.ideal 1016°C
0°14°28°
The full read · show the working · for brown trout · confidence 90%
How the 85 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time75 × 13%9.8
Pressure80 × 7%5.6
Insect activity55 × 12%6.6
Conditions total= 85
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
Conditions
Regional est.
Level
Light rain recently
No gauge reading
Water temp
12.0°C
Estimated
Clarity
Clear
Air temp
11°C
Wind
W 8 km/h
Light breeze
Pressure
1014 hPa
Rain · 48h
6.9 mm
Light rain
Rain · ahead
6.9 mm
Light rain · next 48h

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

Hatch timeline · todayQuiet day

Hatch predictions

Today's headline hatch shown — see all 12 active hatches hour by hour with Pro.

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Evidence
ModelledModerate confidence

Modelled from regional ecology — no survey or occurrence data for this water yet.

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
Excellent — water temperature is right today, though insect activity could be better.
Through the year
0–3 scale · June highlighted
J
F
M
A
M
J
J
A
S
O
N
D
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1

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

Gallery · 1
  1. Terrain map of the venue
    Terrain map
Permits & access
Permit required — see local rules.
  • Kamikōchi is protected; local co-operative rules and a yugyoken apply, with access and method limits
  • Confirm before fishing.
Directions
About this water

The Azusa rises at the heart of the Japanese Alps at Kamikōchi, a valley of such beauty that it is protected and walked by thousands, and through it the river runs gin-clear over pale stones beneath the Hotaka peaks. It holds iwana and stocked rainbows in cold alpine water, and it is as much a pilgrimage to a landscape as a fishing trip — tenkara country in the truest sense.

Under the surface

A clear alpine river at the roof of Honshū, running off the Hotaka and Yari peaks through the protected valley of Kamikōchi over pale volcanic stone. Iwana hold in the cold pockets; the water is as much sacred landscape as fishery, and the native fixed-line tenkara belongs here.

Wading: Cold alpine water, protected park rules, altitude

  • River
  • Volcanic
  • Confined
  • Pool riffle
  • Pocket water
Seasons & zones
  • Charlate February to April → late September to mid-October
Other water nearby · 2
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