big-lost-tailwater

Big Lost River Tailwater is a stretch on Big Lost River, Idaho.

Also called Lower Big Lost River, Lower Lost and Big Lost Below Mackay.

It is fishable.

Below Mackay Reservoir toward the town of Mackay; open year-round and fishes well on spring/winter BWO and midge hatches (Wood River Weekly).

It is downstream of Mackay Reservoir.

Sourced from 4 sites.

Sources: lostriveroutfitters.com (retrieved 2026-10-20), The Perfect Fly Store, Silver Creek (retrieved 2026-10-20), woodriverweekly.com and woodriverweekly.com (2).

Access, closures and rules change; check with the state agency before you go.