Lowland · Mixed · East / Meath, IE

Nanny & Delvin Rivers

Nanny & Delvin Rivers terrain map

Two small east-coast rivers — the Nanny running through Duleek and Julianstown to the sea at Laytown, the Delvin reaching it near Balbriggan.

Prime · Brown Trout
Pheasant Tail Nymph · 14-18
Primelive now
About as good as it gets
River steady at a fishable height. On the feed top to bottom — start on the rises with a dry, drop a nymph if they stay down.
90% confidence
What moved it
  • Level0.71 mLast reading 18h ago
  • Water temp14.8°C
  • ClarityClear
Today's fly
Pheasant Tail Nymph
Pheasant Tail Nymph14-18
Upstream
Conditions on the water
Live gauge
Level
Steady
0.71 m
Last reading 18h ago
Water temp14.8°C
ClarityClear
Weather13°C
WindS 26 km/h
Pressure1016 hPa
Rain · recent2.8 mm
Rain · ahead0.1 mm

Live readings only. Trends shown where the gauge supports them.

Water temperature for Brown Trout
Ideal
14.8°Cideal 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.
Why this works
Excellent — water temperature is right today, though time of day could be better.
Likely species
Hatch timeline · todayPeak at 11am

Hatch predictions

Today's headline hatch shown — see all 12 active hatches hour by hour as a supporter.

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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 4 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
2
1
Mayfly (Green Drake)Hatch
2
2
Large Cinnamon SedgeHatch
2
3
3
2
Daddy Long LegsHatch
2
3
2
CapererHatch
2
3
3
2

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

Ranked for today
Brown Trout fly box
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
About this water

Two small east-coast rivers — the Nanny running through Duleek and Julianstown to the sea at Laytown, the Delvin reaching it near Balbriggan. Each holds a stock of wild brown trout and takes a run of sea trout from late May into summer. The best of the Nanny's trout water is Julianstown up to above Balrath Bridge, fly-only above Bellewstown Bridge. Duleek Anglers and Drogheda & District Anglers hold most of the Nanny; the Delvin is largely riparian-owner water, so enquire locally.

Hatches & food

Two small limestone-based east-coast rivers with modest olive and sedge hatches for the resident trout; summer fishing pivots to flood-run sea trout taking sedges and terrestrials in the tidal lower reaches.

  • Mixed
The full read · show the working · for Brown Trout · confidence 90%
How the 84 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time55 × 13%7.2
Pressure80 × 7%5.6
Insect activity71 × 12%8.5
Conditions total= 84
Can you trust it?
Water temperaturelive gauge readinggauge
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
Seasons & zones
  • Trout 15 February → 30 September

Sea trout: Variable seasonal (2026)

Related guides
Casting instructors near here
Booking & contacts
Permits & access