Tailwater · Mixed · Colorado, US

South Platte — Cheesman Canyon

South Platte — Cheesman Canyon terrain map

Cheesman Canyon is the one that humbles people.

Tomorrow · Not the day for it
Pheasant Tail
Forecast · Tomorrow
Not the day for it
Not much stacked in your favour today. Worth an hour if you are nearby, not worth the special trip.
45% projected
Today's fly
Pheasant Tail
Pheasant Tail
Conditions on the water · Tomorrow
Live gauge
Level
Rising
0.93 m
Lifting fast
Water temp11.5°C
ClarityUnfishable
Weather19°C
WindN 11 km/h
Pressure1016 hPa
Rain · recent0.5 mm
Rain · ahead0.0 mm

The nearest gauge doesn't record temperatures, so we've estimated it — defer to the river keeper's advice.

Water temperature for Brown Trout
Ideal
12°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
Excellent — water temperature is right today, though time of day could be better.
Hatch timeline · tomorrowPeak at 11am

12pm(now) Western Blue-Winged Olive

Stage: On emergersApproach: Emerger or dryActivity: 53%
Peak emergence window5 food groups active

Peak activity at 11am — Western Blue-Winged Olive (Western Blue-Winged Olive, Peak emergence window)

Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 2 guilds with Pro.

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Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Top prey shown — see all 5 with Pro.

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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
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
Brown Trout fly box
Permits & access
Permit required — see local rules.
  • Colorado licence
  • Gold Medal, flies/lures-only, catch-and-release
  • Verify CPW regulations.
What's coming
Plan ahead
5-day outlook
Other water nearby · 3
About this water

Cheesman Canyon is the one that humbles people. It's a hike-in granite gorge below Cheesman Dam holding wild, educated browns and rainbows in water so clear it feels indecent, and the fish have seen every fly ever tied. You sight-fish, you go small, you use tippet you can barely see, and you accept that some of the best fish in Colorado are going to refuse you politely all afternoon. It's catch-and-release flies-and-lures water, technical to the core, and worth every bit of the walk in.

Under the surface

Cheesman Canyon is the South Platte's masterpiece and its hardest exam. Below Cheesman Dam the river drops into a granite slot of the Pikes Peak batholith — great rounded domes and boulders of pale decomposing granite — and runs as a clear, cold, technical tailwater that has humbled more good fishermen than it has pleased. The trout are wild, abundant and famously educated, holding in glassy pools and pocket water where a drag-free drift is a theoretical concept rather than an achievable one. You hike in; there are no roads. The bed is granite boulder and gravel, the water low and clear most of the year, every fish visible and every fish skeptical. Wading is rock-hopping among slick granite. Cheesman is where Colorado anglers go to be reminded that they are not as good as they think they are, and they keep going back.

Wading: Slick granite boulders, hike in only

  • Mixed
  • Confined
  • Step pool
  • Pool riffle
Water quality · US Clean Water Act
  • Aquatic lifeSupporting
What this classification means

EPA ATTAINS assessment unit 'South Platte River, all tributaries.' (COSPUS02a_E), 2024 Integrated Report. Aquatic Life use: Fully Supporting. 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) · COSPUS02a_E

The full read · show the working · for Brown Trout · confidence 75%
How the 81 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time45 × 13%5.9
Pressure80 × 7%5.6
Insect activity59 × 12%7.1
Conditions total= 81
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
Casting instructors near here
Booking & contacts