Freestone · Granite · East / Wicklow, IE

River Liffey (Upper / Blessington)

River Liffey (Upper / Blessington) terrain map

The Liffey rises in the Wicklow Mountains above Blessington — fast, peaty, granite-sourced, and clear in a way that flatters its surroundings.

Today · Closed season
Black Gnat
Forecast · Today
Closed season
Out of season. Try elsewhere.
75% projected
Today's fly
Black Gnat
Black Gnat
Conditions on the water · Today
Proxy gauge
Level
Falling
Proxy
via River Dargle (Tinnehinch Fishery)
Water temp14.1°C
ClarityClearing
Weather13°C
WindN 36 km/h
Pressure1003 hPa
Rain · recent6.2 mm
Rain · ahead2.3 mm

No gauge on this water — conditions are inferred from River Dargle (Tinnehinch Fishery). The trend transfers, the absolute level does not.

Water temperature for Brown Trout
Ideal
14°C est.ideal 10–16°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.
Likely species
Hatch timeline · todayPeak at 12pm

12pm(now) — Heather Fly

Stage: Terrestrials on topApproach: Dry flyActivity: 95%
Also:Daddy Long Legs55%Autumn Dun45%Cinnamon Sedge45%
Peak emergence windowWeather boost11 food groups active

Peak activity at 12pm — Heather Fly (Heather Fly, Peak emergence window)

Sub-surface · on the nymphunder the surface

Hatch predictions

Supporters see the full sub-surface read.

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Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Top prey shown — see all 3 as a supporter.

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Evidence
Survey-backed · regionalHigh confidence

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

Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
Green PeterHatch
2
3
2
Murrough (Great Red Sedge)Hatch
2
3
2
Daddy Long LegsHatch
2
3
2
DuckflyHatch
2
2

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

Ranked for today
Brown Trout fly box
Permits & access
Permit required — see local rules.
  • Eastern Regional Fisheries District
  • Club-managed (Blessington and District AC)
  • Day tickets available
  • State rod licence required.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
About this water

The Liffey rises in the Wicklow Mountains above Blessington — fast, peaty, granite-sourced, and clear in a way that flatters its surroundings. Poulaphuca Reservoir (Blessington Lakes) interrupts the natural flow, and the fishing below the dam is the most consistent part of the upper river: regulated releases maintain a reasonable level through summer, and the tailwater carries good populations of wild brown trout on the dry fly from April. Above the reservoir, the headwater streams hold smaller fish but in spectacular moorland. The upper Liffey is primarily a dry-fly and nymph river for wild brownies averaging seven to ten inches, with occasional larger fish. Fishing is club-managed with day permits available. A good option for the Wicklow-based angler who prefers moving water to lough fishing.

Hatches & food

EPA monitoring on the upper Liffey above Blessington confirms a wide food base, with mayflies (including Ephemera danica), stoneflies, an extensive caddis population, chironomids and blackflies, freshwater shrimp and hoglice, and even native white-clawed crayfish all present in the catchment.

  • Granite
Water quality (WFD)
  • Ecology: Unknown
  • Chemical: Unknown
The full read · show the working · for Brown Trout · confidence 90%
How the 0 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time80 × 13%10.4
Pressure80 × 7%5.6
Insect activity66 × 12%7.9
Conditions total= 87
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via River Dargle (Tinnehinch Fishery)proxy
Prey activitysurvey-backed invertebrate datasurvey
Directions
Seasons & zones
  • Trout 1 March → 30 September
Related guides
Casting instructors near here
Booking & contacts