Stillwater · Mixed · Pembrokeshire, South West Wales (Preseli Mountains)

Llys y Fran Reservoir

A lone angler sits on the bank of Llys y Fran Reservoir fishing, with calm blue water stretching to the dam and green Pembrokeshire countryside beyond.

Pembrokeshire's principal reservoir and one of South Wales's better-known stillwater trout fisheries — a 212-acre working drinking-water reservoir on the Preseli Mountains' southern slopes, dammed across the River Syfynwy in 1972 and run directly by Welsh Water as a proper, well-organised fishery rather than a concession.

Good · Rainbow
Cat's Whisker · 8-12
Goodlive now
Reasonable autumn fishing likely at Llys y Fran Reservoir
Good wave on — drift country. Drift fishing weather — three flies on a long leader.
67% confidence

Llys y Fran Reservoir is often best in spring through autumn.

What moved it
  • WindW 15 km/hGentle breeze
Today's fly
Cat's Whisker
Cat's Whisker8-12
Retrieve, sub-surface
Conditions on the water
Estimate
Wind
Gentle breeze
W 15 km/h
N
W
from the west
Wave20 cm ripple
Water temp10.4°C
Air temp15°C
CloudOvercast
Pressure1019 hPa
Rain · recent0.0 mm

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

How to fish it · for Rainbow
When
The buzzer is on at Llys y Fran Reservoir. The ripple should help fish move and feed more confidently.
Where
Start with Cat's Whisker (8-12) — 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 Cat's Whisker (8-12) — 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

Sedge should come on through the afternoon as the water warms.

Either bank or boat

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

Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 2 guilds as a supporter.

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Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Top prey shown — see all 5 as a supporter.

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Through the year
0–3 scale · October highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Reservoir BuzzerHatch
2
3
3
3
3
3
2
Daphnia SwarmHatch
2
3
3
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

More straightforward stocked-water behaviour than the upland competition reservoirs, with stronger early-season lure and booby bias but still good natural-fly periods.

Bays & launches · 1

Run and booked directly by Welsh Water — the most straightforwardly bookable of the Tier 3 stillwaters.

Llys y Fran — Welsh Water day tickets & boat hireDay tickets
8-hour bank sessions with 2/4/6-fish bag options, or electric boat hire (fly only) by the half or full day.
Visit official site ↗
What's coming
Plan ahead
5-day outlook
Condition match
59%
Cloud50%
Wind65%
Temp60%

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

Other water nearby · 1
Garnffrwd Park
48 km
Brown trout
Gallery · 2
  1. A lone angler sits on the bank of Llys y Fran Reservoir fishing, with calm blue water stretching to the dam and green Pembrokeshire countryside beyond.
    Angling above Llys-y-frân dam
  2. Terrain map of the venue
    Terrain map
About this water

Pembrokeshire's principal reservoir and one of South Wales's better-known stillwater trout fisheries — a 212-acre working drinking-water reservoir on the Preseli Mountains' southern slopes, dammed across the River Syfynwy in 1972 and run directly by Welsh Water as a proper, well-organised fishery rather than a concession. Regularly stocked rainbow trout carry the fishery, backed by a resident head of wild brown trout, fished from the bank or from electric-powered hire boats (fly only from the boats). It's genuinely a working water-supply asset first — Welsh Water suspended fishing here for a stretch in 2024 when a dry spell exposed the banks and forced the launch pontoon to move, which is worth knowing before you plan a trip in a drought year, even though bookings have run normally since.

  • Reservoir
  • Mixed
Why this score
  • Buzzer is in its seasonal window, boosting the chance of targeted feeding.
  • Reservoirs of this kind fish well at this time of year.
Related guides
Big Stillwater Playbookreservoir tacticsReservoir Entomologymatching the hatchThermal Layers & Troutreading depth and temperature
Casting instructors near here
Booking & contacts
Boards & regulators