Freestone · Mixed Sedimentary · New Jersey

Big Flat Brook

A rustic wooden suspension bridge crossing Big Flat Brook, surrounded by lush green woodland, Sussex County, New Jersey.
Poor · Rainbow Trout
Yellow Stimulator · 10-16
Poorlive now
Not the day for it
River steady at a fishable height. Not much stacked in your favour today. Worth an hour if you are nearby, not worth the special trip.
90% confidence
What moved it
  • Level0.60 mLast reading 10h ago
  • Water temp22.1°C
  • ClarityClear
Today's fly
YS
Yellow Stimulator10-16
Proven pattern for this period
Conditions on the water
Live gauge
Level
Steady
0.60 m
Last reading 10h ago
Water temp22.1°C
ClarityClear
Weather23°C
WindSW 24 km/h
Pressure1007 hPa
Rain · recent3.2 mm
Rain · ahead0.0 mm

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

Water temperature for Rainbow Trout
Warm — slow
22°C est.ideal 10–18°C
0°14°28°
How to fish it · for Rainbow 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 22.1°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Hatch timeline · todayQuiet day

Hatch predictions

Today's headline hatch shown — see all 2 active hatches hour by hour with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 2 with Pro.

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Evidence
ModelledModerate confidence

Modelled from regional ecology — no survey or occurrence data for this water yet.

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
2
2
2
2
2
1
Quill GordonHatch
2
2
Blue QuillHatch
2
3
2
HendricksonHatch
2
2
Eastern March BrownHatch
2
2

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

Ranked for today
Rainbow Trout fly box
Permits & access
Permit required — see local rules.
  • New Jersey licence and trout stamp required; fly-fishing-only on the Blewett Tract with delayed-harvest-style special regulations — verify current NJDEP Fish & Wildlife rules and seasonal windows before you fish.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
  1. A rustic wooden suspension bridge crossing Big Flat Brook, surrounded by lush green woodland, Sussex County, New Jersey.
    Shaky
  2. Terrain map of the venue
    Terrain map
Water quality · US Clean Water Act
  • Aquatic life: Impaired
  • Recreation: Impaired
What this classification means

Recreation: Bacteria/pathogen advisory — mind wading cuts and immersion.

EPA ATTAINS assessment unit 'Flat Brook (Tillman Brook to Confluence)' (NJ02040104150010-01), 2022 Integrated Report. Aquatic Life use: Not Supporting. Listed impairment causes: Temperature, Metals Other Than Mercury, Pathogens. This is a Clean Water Act assessment-unit classification (the US analogue of WFD), not a live reading.

Status is for the Clean Water Act assessment unit covering this reach.

EPA ATTAINS (Clean Water Act) · NJ02040104150010-01

The full read · show the working · for Rainbow Trout · confidence 90%
How the 15 is built — score × weight = contribution
Temperature10 × 28%2.8
Flow80 × 22%17.6
Clarity85 × 18%15.3
Feeding Time60 × 13%7.8
Pressure75 × 7%5.3
Insect activity59 × 12%7.1
Limiting factor: Water temperature (22.1°C) is outside Rainbow Trout's preferred range (10–18°C)= 56
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
Cooler water — back toward the 10–18 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout1 January → 31 December
Related guides
Euro Nymphingsubsurface methods
Booking & contacts