below Mackay Reservoir
As of July 28, 2026, the Big Lost River is fishing Fair (5.5/10): flows are 416 cfs, Baetis activity, reported by 1 shop.
Last updated
Reports indicate fair conditions. flow at 416 cfs.
Cold tailwater below Mackay Reservoir. Large rainbows. Best late June through September.
Current Flow
416cfs
| Insect | Stage | Timing |
|---|---|---|
| Baetis | dun | morning |
| PMD | dun | morning |
| Trico | dun | morning |
| Cranefly | adult | morning |
| Yellow Sally | adult | morning |
| Golden Stone | adult | morning |
| Caddis | adult | — |
| Stonefly | adult | — |
Silver Creek Outfitters
Flows remain high at around 450-457 CFS limiting access, but decent Baetis, PMD, and Trico hatches occur throughout the morning and dwindle in the afternoon. Craneflies are also active and can draw vicious strikes.
Silver Creek Outfitters
At 433 cfs the river is still very high and difficult to cross, but strong waders can move about. Good morning hatches of PMDs, Baetis, Craneflies, and Tricos are present; nymphing remains the most productive technique.
Silver Creek Outfitters
At 433 cfs, strong waders can navigate but the river is still very high and difficult to cross; good morning hatches of PMDs, Baetis, Craneflies, and a few Tricos are present. Nymphing remains the most productive method.
Silver Creek Outfitters
For the first time this summer, flows are down to around 400 CFS making wading doable for experienced anglers, though fishing access remains limited. Decent Baetis, PMDs, Yellow Sallies, and golden stones are hatching in the AM with fishing slowing as the day warms.
Silver Creek Outfitters
With flows around 470 CFS, wading is difficult and access is limited, but strong waders will find decent fishing with prolific PMD and Golden Stone hatches through mid-morning. Afternoon action generally slows as the day heats up.
Silver Creek Outfitters
Flows below Mackay are bouncing up and down and remain too high for safe wading in most conditions. Wading becomes possible for strong waders around 350 cfs, but at 500 cfs and above access is very limited.
Silver Creek Outfitters
Flows are too high for safe wading at 500 CFS, making fishing access limited and wading difficult to impossible. Conditions are unsafe for most anglers.
Silver Creek Outfitters
Flows remain too high for safe wading at 695 CFS, bouncing up and down. Access is limited above 500 CFS; strong waders can navigate the river once flows drop to around 350 CFS.
Silver Creek Outfitters
Flows over 660 CFS make safe wading impossible; access is very limited above 500 CFS. The river is unfishable for most anglers at current levels.
Silver Creek Outfitters
Currently at 513 cfs below Mackay with limited access; best to wait until flows drop to around 300 cfs. The upper river and Trail Creek Pass area also have very high flows with limited fishing opportunities.
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