Tailwater · Mixed · Northern California, US

Lower Mokelumne River

Still water on the Mokelumne River near Lodi, California, with trees and a small boat reflected on the surface.
Today · About as good as it gets
Czech Nymph
Forecast · Today
About as good as it gets
On the feed top to bottom — start on the rises with a dry, drop a nymph if they stay down.
90% projected
Today's fly
Czech Nymph
Czech Nymph
Conditions on the water · Today
Estimate
Level
Dry recently
No gauge reading
Water temp14.3°C
ClarityClear
Weather21°C
WindN 12 km/h
Pressure1018 hPa
Rain · recent0.0 mm
Rain · ahead0.0 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Water temperature for Rainbow Trout
Ideal
14°C est.ideal 10–18°C
0°14°28°

A dam sets this river's temperature, not the weather, so it can shift several degrees within hours when the release changes. It also warms as it runs away from the dam.

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
Excellent — conditions well-balanced, with water temperature particularly in your favour.
Likely species
Mayflies
Chironomids
Gammarids
Hatch timeline · todayPeak at 11 Uhr

12 Uhr(now) — Western Blue-Winged Olive

Stage: On emergersApproach: Emerger or dryActivity: 40%
Peak emergence window6 food groups active

Peak activity at 11 Uhr — Western Blue-Winged Olive (Western Blue-Winged Olive, 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
Records-basedModerate confidence

Based on species-occurrence records, not local invertebrate surveys.

Through the year
0–3 scale · October 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
Western Blue-Winged OliveHatch
2
3
3
3
3
3
3
3
2
Pale Morning DunHatch
2
3
3
2
TricoHatch
2
3
2
Black MidgeHatch
2
3
3
3
3
3
3
3
3
3
3
2

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

Ranked for today
Fly box · Rainbow Trout
Permits & access
Permit required — see local rules.
  • Open all year; barbless, with low-flow / steelhead closures — check CDFW
  • ESA-listed steelhead present: handle with care
  • Flow tracks Camanche releases.
What's coming
Plan ahead
5-day outlook
Other water nearby · 2
Lower American River
49 km
77
Rainbow trout
Lower Stanislaus River
55 km
20
Rainbow trout
Gallery · 2
  1. Still water on the Mokelumne River near Lodi, California, with trees and a small boat reflected on the surface.
    Symmetry
  2. Terrain map of the venue
    Terrain map
Conservation note

Holds ESA-listed Central Valley steelhead. We surface their presence only — no catch score, no go-get-'em. Treat any you encounter as the rare thing they are.

Water quality · US Clean Water Act
  • Aquatic life: Impaired
  • Fish consumption: Impaired
What this classification means

Fish consumption: Consumption advisory (Metals Other Than Mercury) — fish for sport, not the table.

EPA ATTAINS assessment unit 'Mokelumne River, Lower (in Delta Waterways, eastern portion)' (CAR5440000019980818095133), 2024 Integrated Report. Aquatic Life use: Not Supporting. Listed impairment causes: Oxygen Depletion, Metals Other Than Mercury, Mercury, Total Toxics. 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) · CAR5440000019980818095133

The full read · show the working · for Rainbow Trout · confidence 90%
How the 84 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity85 × 18%15.3
Feeding Time80 × 13%10.4
Pressure75 × 7%5.3
Insect activity65 × 12%7.8
Conditions total= 84
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout 1 January → 31 December
Related guides
Euro Nymphingsubsurface methods
Casting instructors near here
Booking & contacts