Spate · Slate · West Wales / Carmarthenshire

Towy (Tywi)

The River Towy flowing in broad meanders through the valley below Dinefwr Castle near Llandeilo.
Contributor photo

River Towy below Dinefwr Castle

M J Roscoe - CC BY-SA 2.0

Wales's premier sewin (sea trout) river and major salmon river.

Good · Brown Trout
CDC Emerger · 16-18
Goodlive now
A proper day on the water
River dropping into shape after a lift. Fishing well — get there before it drops out.
75% confidence
What moved it
  • Level0.92 mDropping after lift
  • Water temp14.6°C
  • ClarityClear
Today’s fly
CDC Emerger
CDC Emerger16-18
Upstream dry, in the film
Conditions on the water
Live gauge
Level
Steady
0.92 m
Dropping after lift
Water temp14.6°C
ClarityClear
Weather13°C
WindW 8 km/h
Pressure1023 hPa
Rain · recent0.0 mm
Rain · ahead2.7 mm

Live readings — water temperature is an estimate where the gauge does not record it.

Water temperature for brown trout
Ideal
15°C est.ideal 10–16°C
0°14°28°
How to fish it · for brown trout
When
Through the open trout season. Spring olives April through May; sedges through summer; small dark flies into autumn close. Spate-driven — fish 12 to 24 hours after rain.
Where
Pool tails, riffle heads, and the seams behind boulders through the upper and middle Tywi. Welsh freestone — pocket-to-pocket reading.
Method
Upstream dry to risers; dry-dropper through the riffles. North Country spider on the swing in cooler water. Spate-driven on falling water.
Kit
9 ft #4 — Welsh freestone default. Floating line, 9 to 12 ft leader to 4 to 5 lb fluoro. Studded boots — slate slabs run slick.
Why this works
Good — water temperature is working for you, but time of day is the limiting factor today.
Hatch timeline · todayQuiet day

Hatch predictions

Today's headline hatch shown — see all 7 active hatches hour by hour with Pro.

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Evidence
Survey-backed · regionalModerate confidence

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

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Salmon runRun
1
2
2
2
2
2
1
Trout seasonSeason
1
2
2
2
2
2
1
Daddy Long LegsHatch
2
3
2
March BrownHatch
2
3
2
GrannomHatch
2
2
Large StoneflyHatch
2
3
2

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

Ranked for today
Brown Trout fly box
BB
Black Beetle
14-18 · Pattern
Upstream dry, on top
Beats · 2
Main Towy — association water (Llandovery to Carmarthen)Access varies
The Towy (Tywi) is one of the finest sea trout — sewin — rivers in the British Isles, with a good run of salmon to autumn and brown trout throughout.
Golden Grove & estate beatsAccess varies
Alongside the associations, several private estate beats on the lower and middle Towy — including a cluster around Golden Grove (Cilsane, Dryslwyn Castle, Glanyrafon, Upper and Lower Ro Fawr) — are let to visiting rods through the Fishing Passport.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Cothi
19 km
80
Brown trout · Salmon · Sea trout
Afon Twrch
22 km
84
Brown trout
Wye
28 km
Brown trout · Salmon · Grayling
Neath
30 km
Brown trout · Salmon · Sea trout
Tawe
31 km
Brown trout · Salmon · Sea trout
Gallery · 6
  1. The River Towy flowing in broad meanders through the valley below Dinefwr Castle near Llandeilo.
    River Towy below Dinefwr Castle
  2. The River Towy running through Llandovery, Carmarthenshire, with the valley beyond.
    River Towy at Llandovery
  3. A wide view of the River Towy flowing through the Llangunnor reach at Carmarthen.
    River Towy at Carmarthen
  4. The River Towy at Llandilo-yr-ynys near Nantgaredig, a wide shallow reach in Carmarthenshire.
    River Towy at Llandilo-yr-ynys, Nantgaredig
  5. The Afon Tywi winding through its flood plain near Llandovery, Carmarthenshire.
    Afon Tywi near Llandovery
  6. Terrain map of the venue
    Terrain map
About this water

Wales's premier sewin (sea trout) river and major salmon river. Night fishing for sewin from April through summer is legendary — large fish, aggressive takes. Salmon from February onwards. Fish sinking-tip line with medium tubes in spring for salmon; switch to smaller doubles and wet flies for daytime fishing. Sea trout take throughout spring and summer; night fishing (June–August, particularly July) is most productive. Flows through Llandeilo and Carmarthen. Slate and schist bedrock underlie this river. 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.

  • Slate
Water quality (WFD)
  • Ecology: Good
  • Chemical: Unknown
What this classification means

NRW WFD Cycle 3 — Tywi (confluence with Cothi to spring tidal limit): Good ecological status; the association main-stem water (Llandovery–Carmarthen). Corrected 2026-06-18 from a Gwili-tributary tag (Crychiau), not the Towy main stem. Source: NRW DataMapWales WFD Cycle 3 classification layer.

NRW (Wales) · GB110060029290

The full read · show the working · for brown trout · confidence 75%
How the 79 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time40 × 13%5.2
Pressure80 × 7%5.6
Insect activity42 × 12%5.0
Conditions total= 79
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Salmon1 April → 17 October
  • Trout3 March → 30 September

Sea trout: Variable seasonal (2026) — NRW monitoring places 32 of 33 Welsh sea trout stocks in the 'At Risk' category. The Towy (Tywi) remains Wales's most productive sewin river and holds genuine runs, but stocks are materially below their 1970s–80s peak. Condition-sensitive: night fishing after rain is productive; low summer water is difficult. Catch-and-release is the conservation default on most beats.

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 Tywi was one of Wales's premier salmon rivers; catches have collapsed.

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