Stillwater · Limestone · North Wales / Powys

Lake Vyrnwy

Broad view of Lake Vyrnwy reservoir with calm water, wooded hillsides, and the shoreline stretching into the distance.
Contributor photo

Lake Vyrnwy reservoir

Rosser1954 - CC BY 4.0

Lake Vyrnwy is the reservoir that made fly fishing accessible to the ordinary angler.

Good · Rainbow
Olive Damsel · 10-12
Goodlive now
Reasonable summer fishing likely at Lake Vyrnwy
Good wave on — drift country. Drift fishing weather — three flies on a long leader.
68% confidence
What moved it
  • WindSW 18 km/hGentle breeze
Today’s fly
OD
Olive Damsel10-12
Retrieve, sub-surface
Conditions on the water
Live gauge
Wind
Gentle breeze
SW 18 km/h
N
SW
from the south-west
Wave20 cm ripple
Water temp—
Air temp15°C
CloudBroken
Pressure1019 hPa
Rain · recent0.0 mm

Some readings unavailable — check directly before fishing.

How to fish it · for rainbow
When
The buzzer is on at Lake Vyrnwy. Murrough may also come into play as the day develops. The ripple should help fish move and feed more confidently.
Where
Start with Olive Damsel (10-12) — on the point. 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 Olive Damsel (10-12) — on the point. 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

If the main plan stalls, drop to a size 14–16 midge — switch to a washing-line or suspender rig and change drift line before you change food group.

Watch for

Watch for Murrough towards evening — this could be the best window of the day.

Either bank or boat

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

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
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
77%
Cloud70%
Wind65%
Temp100%

A good match for this venue — most conditions are close to what it fishes best in.

Other water nearby · 5
Afon Eden (Welsh)
28 km
Brown trout
Chirk Fisheries
32 km
Brown trout · Rainbow trout
Cregennan Lakes
32 km
Brown trout · Rainbow trout
Alwen Reservoir
33 km
Brown trout · Rainbow trout
Afon Prysor
33 km
Brown trout
Gallery · 6
  1. Broad view of Lake Vyrnwy reservoir with calm water, wooded hillsides, and the shoreline stretching into the distance.
    Lake Vyrnwy reservoir
  2. The Victorian Gothic straining tower and approach bridge standing in Lake Vyrnwy, reservoir water surrounding it.
    Lake Vyrnwy straining tower
  3. The stone dam wall of Lake Vyrnwy with the reservoir impounded behind it and wooded hillsides on the far bank.
    Lake Vyrnwy dam and reservoir
  4. Elevated panoramic view over Lake Vyrnwy showing the dam, the straining tower, and the full length of the reservoir.
    Lake Vyrnwy from Craig garth-bwlch
  5. Drone aerial photograph over Lake Vyrnwy reservoir in autumn, the open water ringed by forested hillsides.
    Lake Vyrnwy from the air
  6. Terrain map of the venue
    Terrain map
About this water

Lake Vyrnwy is the reservoir that made fly fishing accessible to the ordinary angler. Built in 1889 and now managed by Scottish Water, Vyrnwy holds a special place in British fly-fishing history — it was here that the dry-fly revolution began on still water, where Sutherland and his peers proved that a trout rising on a reservoir could be taken with the same delicate tactics used on chalk streams. The water is fished from bank and boat, and the limestone geology produces reliable food patterns. Buzzers hatch from April, damsels from June, and sedges cloud the evening air through late summer. The valley setting and native woodland give it a wild, unhurried feel despite the managed access. This is a pilgrimage water — worth scheduling your life around.

  • Reservoir
  • Limestone
Water quality (WFD)
  • Ecology: Moderate
  • Chemical: Unknown
What this classification means

NRW WFD Cycle 3 (lake) — Llyn Efyrnwy / Lake Vyrnwy: Moderate ecological status. Re-tagged 2026-06-18 from a feeder-river reach to the reservoir's own lake waterbody. Source: NRW DataMapWales WFD Cycle 3 classification layer.

NRW (Wales) · GB30935568

Why this score
  • Temperature (cool) is in the sweet spot for summer fishing.
  • Buzzer is in its seasonal window, boosting the chance of targeted feeding.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout15 March → 5 October
Related guides
Big Stillwater Playbookreservoir tacticsReservoir Entomologymatching the hatchThermal Layers & Troutreading depth and temperature
Booking & contacts