Two-Week Closure Puts Idaho’s Best Stocked Trout Waters Off Limits to Anglers

Road construction at one of Idaho’s premier trout fishing destinations will significantly impact angler access for the next two weeks. Starting Monday, September 22, at 7 a.m., a portion of Horsethief Road will be closed as crews begin paving work on the west side of Horsethief Reservoir in Valley County.

The closure begins at the cattle guard near the intersection of Horsethief Road and National Forest Development Road 433, extending south to the YMCA camp. Idaho Fish and Game anticipates the work will take just under two weeks, with west side access reopening to the public on October 1.

While the main access road will be closed, National Forest Development Road 433 will remain open, providing a route to the east side of the reservoir. However, this alternative effectively limits access to walk-in only. With camp hosts having departed for the season, the gate to the boat ramp at Trout Landing on the east side is already closed, eliminating boat launching opportunities during the construction period.

This timing coincides with the end of the camping season, as Horsethief Reservoir Campground closed on September 14, two weeks before the road work began.

Horsethief Reservoir spans 260 acres and ranks among Idaho’s most productive trout fisheries. The Idaho Department of Fish and Game regularly stocks the reservoir with rainbow trout, brown trout, and kokanee salmon. Current bag limits allow six trout, six kokanee, and 25 brook trout.

The reservoir operates under a 5 mph speed limit and maintains no-wake status year-round. Even when full access returns, boaters should remember these restrictions apply to all watercraft.

Located approximately 75 miles north of Boise and 9 miles east of Cascade, Horsethief Reservoir typically offers excellent late-season fishing opportunities. While the road closure temporarily complicates access, walk-in fishing from the east side remains possible for dedicated anglers willing to make the extra effort.

The timing of this construction project, occurring after the camping season ends but before winter closure, minimizes impact on peak fishing periods. Once work completes on October 1, full access will resume just as fall fishing typically picks up momentum.

For current conditions and access updates, check with Idaho Fish and Game before making the trip to this popular mountain reservoir.