Freestone · Limestone · North Wales / Vale of Clwyd

River Clwyd

Wide view of the River Clwyd valley from a footpath on the southwest side of Ruthin.

North Wales salmon and sea trout river flowing through the Vale of Clwyd.

Poor · Brown Trout
CDC Emerger · 16-18
Poorlive now
Not the day for it
River temperature is the limiting factor today, not the flow. This is not the day to push it. Check the thermal advice above before you head out.
90% confidence
What moved it
  • Level0.27 mLast reading 19h ago
  • Water temp22.4°C
  • ClarityClear
Today's fly
CDC Emerger
CDC Emerger16-18
Upstream dry, in the film
Conditions on the water
Live gauge
Level
Steady
0.27 m
Last reading 19h ago
Water temp22.4°C
ClarityClear
Weather27°C
WindSW 7 km/h
Pressure1020 hPa
Rain · recent0.0 mm
Rain · ahead0.9 mm

The nearest gauge doesn't record temperatures, so we've estimated it — defer to the river keeper's advice.

Water temperature for Brown Trout
Warm — slow
22°C est.ideal 1016°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.
Why this works
Water at 22.4°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Hatch timeline · todayPeak at 6am

Hatch predictions

Today's headline hatch shown — see all 3 active hatches hour by hour with Pro.

Start free trial

14-day free trial. Cancel anytime.

Sub-surface · on the nymphunder the surface

Hatch predictions

See the full sub-surface read with Pro.

Start free trial

14-day free trial. Cancel anytime.

Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 2 with Pro.

Start free trial

14-day free trial. Cancel anytime.

Evidence
Survey-backed · regionalHigh confidence

Backed by regional invertebrate surveys; no sampling on this exact reach yet.

Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Salmon runRun
1
2
2
2
2
2
2
1
Trout seasonSeason
1
2
2
2
2
2
1
Daddy Long LegsHatch
2
3
2
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1

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

Ranked for today
Brown Trout fly box

Wild-river first principles. Early-season nymphs and practical searching, then dry flies, emergers and spiders as hatches and surface activity improve.

BB
Black Beetle
14-18 · Pattern
Upstream dry, on top
Beats · 5 · 2 reaches
Rhyl & St Asaph AA — visitor permitsAccess varies
The Clwyd is a sewin river first.
Clwyd tributaries · 4 beatsMixed
River Elwy — Vale of Clwyd AC (Kinmel Estate), River Elwy — Rhyl & St Asaph AA, River Aled — Rhyl & St Asaph AA, River Wheeler (Afon Chwiler) — Vale of Clwyd AC
The 4 beats
River Elwy — Vale of Clwyd AC (Kinmel Estate)Members
Vale of Clwyd Angling Club
Six beats on the lower Elwy near the Kinmel Estate, closer to St Asaph — the Elwy is one of Wales's more productive sea trout (sewin) fisheries, with fish of 5-10lb routinely caught.
Members only. Annual membership around £145 (renew before 31 March).
River Elwy — Rhyl & St Asaph AADay tickets
Rhyl & St Asaph Angling Association
About 9 beats further upstream, from St Asaph town water up toward Llanfair Talhaiarn — part of a combined ~20-mile Clwyd/Elwy/Aled holding.
Visitor day ticket £15 (1-day) / £60 (5-day), covering Clwyd/Elwy/Aled beats — confirm which specific beats are included before travelling.
River Aled — Rhyl & St Asaph AAMembers
Rhyl & St Asaph Angling Association
A single double-bank beat downstream of Llansannan, on this smaller Elwy tributary that rises at Llyn Aled reservoir. Best later in the season for migratory fish; salmon is not confirmed on this specific beat.
RASAAA membership ~£180 adult; some beats may be included in the visitor day-ticket scheme, confirm before travelling.
River Wheeler (Afon Chwiler) — Vale of Clwyd ACMembers
Vale of Clwyd Angling Club
A single beat near Bodfari on this small Clwyd tributary, followed for its whole length by the A541. Established brown trout population, with sea trout and salmon running when water heights allow.
Members only — no day-ticket route found for this beat.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 6
  1. Wide view of the River Clwyd valley from a footpath on the southwest side of Ruthin.
    River Clwyd valley, southwest of Ruthin
  2. The Afon Clwyd at Trefnant, between St Asaph and Denbigh.
    Afon Clwyd at Trefnant
  3. The River Clwyd flowing past the town of Rhuddlan in North Wales.
    River Clwyd at Rhuddlan
  4. The River Clwyd winding through Ruthin Park, Ruthin.
    The River Clwyd, Ruthin Park
  5. The River Clwyd flowing through Ruthin in the Vale of Clwyd.
    River Clwyd, Ruthin
  6. Terrain map of the venue
    Terrain map
About this water

North Wales salmon and sea trout river flowing through the Vale of Clwyd. Limestone-influenced lower reaches support good hatches and alkaline conditions. Spring salmon and summer/autumn sea trout. Fish sinking-tip with medium tubes for salmon, smaller wets for sea trout. Club water with day ticket access available. A limestone system with more favorable conditions than purely slate rivers. Atlantic salmon are under serious conservation pressure — Natural Resources Wales mandates catch-and-release for salmon on all rivers, so all fish must be returned.

Under the surface

The Clwyd rises in the Clocaenog Forest north-west of Corwen and runs thirty-five miles to the Irish Sea at Rhyl, its course bent sharply north-east by the Vale of Clwyd Fault near Melin-y-wig. Above Ruthin it threads a narrow valley; below, it leaves the hills and meanders through the broad, fertile farmland of the Vale of Clwyd, gathering the substantial Clywedog south of Denbigh before passing St Asaph to the tide. It is a lowland river of clear water over gravel and rock, quick to colour and rise after rain off the high ground. Salmon push through in March and May with the main run in high summer, and the sewin — Welsh sea trout — move in numbers from June. The bed is gravel and rock through a soft agricultural vale. Wading is easy on the whole, with the usual care where the river runs deep and strong below the weirs.

Wading: Deep, strong water below the weirs

Sea trout here

Summer-autumn runs (June–September), primarily nocturnal

  • Limestone
  • Unconfined
  • Pool riffle
  • Meandering
Water quality (WFD)
  • EcologyModerate
  • ChemicalUnknown

NRW (Wales) · UKGB110066059960

The full read · show the working · for Brown Trout · confidence 90%
How the 8 is built — score × weight = contribution
Temperature4 × 28%1.1
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity56 × 12%6.7
Limiting factor: Water temperature (22.4°C) is outside Brown Trout's preferred range (10–16°C)= 57
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Seasons & zones
  • Salmon 20 March17 October
  • Trout 3 March30 September

Sea trout: Variable seasonal (2026) — NRW At Risk classification. North Wales river. Sea trout present but stocks are among the more marginal in Wales; classified At Risk. Secondary quarry behind salmon.

Salmon: Negligible (2026) — NRW / EA 2024 Salmon Stocks Assessment classifies this Welsh principal salmon river 'at risk' — egg deposition below Conservation Limit. All Wales byelaws (in force 2020-2030) make catch & release mandatory. Conservation priority; not a salmon fishing destination. The Clwyd's salmon run is much reduced; classified at risk.

Related guides
Casting instructors near here
Booking & contacts
Clubs & associations