- Ecology: Moderate
- Chemical: Failing to achieve good
WFD classification · CZHVL_1250
Water temperature for Brown Trout
Warm — slow22°C est.ideal 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
Water at 22.1°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Sub-surface · on the nymphunder the surface
Hatch predictions
See the full sub-surface read with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
See what else is on the menu with Pro.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalModerate confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
1
Grayling seasonSeason
1
2
2
2
2
1
Large Dark OliveHatch
1
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Autumn OliveHatch
1
2
1
GrannomHatch
1
1
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.
- State licence + local permit
- Multiple quality sections with fly-only rule
- Brown trout protected Sep 1–Apr 15
- Grayling protected Dec 1–Jun 15.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
File:View to Písek from Otava River (1).JPG Terrain map
Water quality (WFD)
The full read · show the working · for Brown Trout · confidence 90%
How the 12 is built — score × weight = contribution
Temperature6 × 28%1.7
Flow15 × 22%3.3
Clarity95 × 18%17.1
Feeding Time65 × 13%8.5
Pressure80 × 7%5.6
Insect activity22 × 12%2.6
Limiting factor: Water temperature (22.1°C) is outside Brown Trout's preferred range (10–16°C)= 39
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
A drop and clear would lift the flow and clarity scores.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 16 April → 31 August
- Grayling 16 June → 30 November
Czech national rule: grayling (lipan podhorní) protected 1 December – 15 June. Open window is 16 June – 30 November. Czech Anglers Union (ČRS) salmonid fisheries also have method and access rules — check the local ČRS district permit for specific conditions.
Closed in spring for spawning.
Prime sport 1 September → 30 November
Related guides
Booking & contacts
Otava
Water temperature for Brown Trout
Warm — slow22°C est.ideal 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
Water at 22.1°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Sub-surface · on the nymphunder the surface
Hatch predictions
See the full sub-surface read with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
See what else is on the menu with Pro.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalModerate confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
1
Grayling seasonSeason
1
2
2
2
2
1
Large Dark OliveHatch
1
2
2
1
Blue Winged OliveHatch
1
2
2
2
2
1
Autumn OliveHatch
1
2
1
GrannomHatch
1
1
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.
- State licence + local permit
- Multiple quality sections with fly-only rule
- Brown trout protected Sep 1–Apr 15
- Grayling protected Dec 1–Jun 15.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
File:View to Písek from Otava River (1).JPG Terrain map
Water quality (WFD)
- Ecology: Moderate
- Chemical: Failing to achieve good
WFD classification · CZHVL_1250
The full read · show the working · for Brown Trout · confidence 90%
How the 12 is built — score × weight = contribution
Temperature6 × 28%1.7
Flow15 × 22%3.3
Clarity95 × 18%17.1
Feeding Time65 × 13%8.5
Pressure80 × 7%5.6
Insect activity22 × 12%2.6
Limiting factor: Water temperature (22.1°C) is outside Brown Trout's preferred range (10–16°C)= 39
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
A drop and clear would lift the flow and clarity scores.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 16 April → 31 August
- Grayling 16 June → 30 November
Czech national rule: grayling (lipan podhorní) protected 1 December – 15 June. Open window is 16 June – 30 November. Czech Anglers Union (ČRS) salmonid fisheries also have method and access rules — check the local ČRS district permit for specific conditions.
Closed in spring for spawning.
Prime sport 1 September → 30 November
Related guides
Booking & contacts