Freestone · Volcanic · Eastern Sierra, US

Upper Owens River

The Upper Owens River in winter with sunlight reflections on the water, Long Valley, Mono County.

The Upper Owens is a meandering high-desert meadow river feeding into Crowley, and it carries one of the Eastern Sierra's worst-kept secrets: big lake-run browns and rainbows that run up out of the reservoir to spawn and feed.

Tomorrow · About as good as it gets
Pheasant Tail
Forecast · Tomorrow
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.
75% projected
Today's fly
Pheasant Tail
Pheasant Tail
Conditions on the water · Tomorrow
Estimate
Level
Dry recently
No gauge reading
Water temp10.5°C
ClarityClear
Weather14°C
WindN 9 km/h
Pressure1015 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 Brown Trout
Ideal
11°C est.ideal 1016°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
Good — water temperature is right today, though time of day could be better.
Likely species
Hatch timeline · tomorrowPeak at 12pm

12pm(now) Mahogany Dun

Stage: On emergersApproach: Emerger or dryActivity: 95%
Also:Black Midge43%
Peak emergence windowDegree-days at peak6 food groups active

Peak activity at 12pm — Mahogany Dun (Mahogany Dun, Peak emergence window)

Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 3 guilds with Pro.

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14-day free trial. Cancel anytime.

Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Top prey shown — see all 2 with Pro.

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14-day free trial. Cancel anytime.

Evidence
Records-basedModerate confidence

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

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
2
2
2
2
1
Brown DunHatch
2
3
3
3
3
3
3
2
Western Green DrakeHatch
2
2
Flav (Small Western Green Drake)Hatch
2
3
2
Mahogany DunHatch
2
2

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

Ranked for today
Brown Trout fly box
SD
Sex Dungeon
2-6 · Pattern
Proven pattern for this period
Permits & access
Permit required — see local rules.
  • Year-round on the open reaches, but reach-specific seasonal/gear rules apply near the Crowley inflow — verify against CDFW
  • SPAWNING ETHICS: big lake-run fish are often on redds; do not target spawners or wade on spawning beds.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
  1. The Upper Owens River in winter with sunlight reflections on the water, Long Valley, Mono County.
    Upper Owens in winter
  2. Terrain map of the venue
    Terrain map
About this water

The Upper Owens is a meandering high-desert meadow river feeding into Crowley, and it carries one of the Eastern Sierra's worst-kept secrets: big lake-run browns and rainbows that run up out of the reservoir to spawn and feed. It's a year-round fishery with easy access and genuine quality, fishable with nymphs, streamers and — when the fish are looking up — dries over rising trout in the undercut meadow bends. A word on ethics: those big migratory fish are often on or near redds, and standing on a spawning bed to chase a hen is bad form and bad for the river. Fish the runs and holding water, leave the spawners be, and the Upper Owens stays the quiet gem it is.

  • Volcanic
Water quality · US Clean Water Act
  • Aquatic lifeNot assessed
  • RecreationImpaired
What this classification means

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

EPA ATTAINS assessment unit 'Owens River (Long HA)' (CAR6031009020011204130840), 2024 Integrated Report. Aquatic Life use: Insufficient Information. Listed impairment causes: 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) · CAR6031009020011204130840

The full read · show the working · for Brown Trout · confidence 75%
How the 76 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time45 × 13%5.9
Pressure80 × 7%5.6
Insect activity52 × 12%6.2
Conditions total= 76
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
  • Trout 1 January31 December
Related guides
Booking & contacts