Stillwater · Mixed · Monmouthshire / Gwent

Llandegfedd Reservoir

Llandegfedd Reservoir as a blue expanse in the rolling Welsh landscape, from the mountain road south of Pontypool.
Fair · Rainbow
Coch-y-Bonddu Beetle · 10-14
A respectable few hours, if you choose your moments
Water temperature is the limiting factor today, not the wave. Fish dawn or dusk if you go at all, and handle everything with extra care.
48% confidence
limited data

Peak season here starts around September — worth planning ahead.

What moved it
  • WindSE 7 km/hLight breeze
Today's fly
CY
Coch-y-Bonddu Beetle10-14
Upstream dry, on top
Conditions on the water
Live gauge
Wind
Light breeze
SE 7 km/h
N
SE
from the south-east
WaveRipple
Water temp—
Air temp27°C
CloudClear
Pressure1021 hPa
Rain · recent0.0 mm

Some readings unavailable — check directly before fishing.

How to fish it · for Rainbow
When
Conditions are not ideal but fishable at Llandegfedd Reservoir. The ripple should help fish move and feed more confidently. Very warm conditions — trout have a narrower safe zone of cool, oxygen-rich water. Fish only at first light or last light, use barbless hooks, keep fish in the water during release, and stop if fish struggle to recover. Early morning is often the most productive window in summer — make the most of it.
Where
Start with Coch-y-Bonddu Beetle (10-14) — on the bob / top dropper. Rainbows respond to more active retrieves — try short strips between pauses. If that does not produce, switch depth or speed before changing the pattern entirely.
The plan
Plan A

Start with Coch-y-Bonddu Beetle (10-14) — on the bob / top dropper. Rainbows respond to more active retrieves — try short strips between pauses. If that does not produce, switch depth or speed before changing the pattern entirely.

Plan B

Fish early and late, try deeper during the heat of the day with a fast-sinking line.

Watch for

Buzzers may strengthen through the middle of the day as conditions warm.

Either bank or boat

Good ripple suits both bank and boat. Bank: work inflows, dam walls, and points. Boat: broadside drift covering wind lanes.

Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 3 with Pro.

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Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
2
2
1
Daphnia SwarmHatch
2
3
3
3
2
Daddy Long LegsHatch
2
3
2
Lake OliveHatch
2
3
3
3
3
3
2
Silverhorns & LonghornsHatch
1
2
2
2
1

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

Ranked for today
Rainbow fly box
What's coming
Plan ahead
5-day outlook
Condition match
55%
Cloud25%
Wind100%
Temp25%

A reasonable day here, though temperature isn't quite in the sweet spot.

Other water nearby · 5
River Rhymney
19 km
Brown trout · Sea trout
Bargoed Park
23 km
Brown trout · Rainbow trout
Bigwell Fly Fishery
26 km
Rainbow trout · Brown trout
Talybont Reservoir
30 km
Brown trout
Jacklands Fishing Lakes
32 km
Rainbow trout · Brown trout
Gallery · 6
  1. Llandegfedd Reservoir as a blue expanse in the rolling Welsh landscape, from the mountain road south of Pontypool.
    Llandegfedd Reservoir
  2. Llandegfedd Reservoir glowing bright blue against the Welsh countryside, from the mountainside north of Blaen Bran.
    Blue Llandegfedd Reservoir
  3. The southern basin of Llandegfedd Reservoir looking north-northwest, with Sluvad Wood on the far shore.
    Llandegfedd Reservoir (south)
  4. Llandegfedd Reservoir in late December, the open water in winter conditions near Pontypool.
    Llandegfedd Reservoir in winter
  5. Open water of Llandegfedd Reservoir from the dam, looking east-northeast across the main basin.
    Llandegfedd Reservoir from the dam
  6. Terrain map of the venue
    Terrain map
Water quality (WFD)
  • Ecology: Moderate
  • Chemical: Unknown
What this classification means

NRW WFD Cycle 3 (lake) — Llandegfedd Reservoir: Moderate ecological status. Re-tagged 2026-06-18 from a river reach to the reservoir's own lake waterbody (was recorded Good). Source: NRW DataMapWales WFD Cycle 3 classification layer.

NRW (Wales) · GB30941363

Why this score
  • Wind conditions (ripple) closely match what this water fishes best in.
  • Buzzers are in their seasonal window, boosting the chance of targeted feeding.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout March → November
Related guides
Big Stillwater Playbookreservoir tacticsReservoir Entomologymatching the hatchThermal Layers & Troutreading depth and temperature
Casting instructors near here
Booking & contacts
Clubs & associations