Idaho Fishing Reports ยท Upper Snake Region
The Harriman Ranch, or Railroad Ranch, is the famous flat-water stretch of the Henrys Fork, where big rainbows sip tiny dries in clear spring-creek water.
Looking for the latest Henrys Fork (Harriman Ranch) river report? This page is updated by the AvidMax fly shop team with live flows, current conditions, hatches and the flies working now on the Henrys Fork (Harriman Ranch).
Current flows
Heads up: The Harriman Ranch section is fly-fishing only and catch-and-release, with a season that opens in mid-June and closes in late fall. Check the current IDFG rules before you go.
Wind forecast
Henrys Fork fishing report
Updated November 7, 2026.
It is late season on the ranch. Expect cold mornings, few anglers and BWOs on cloudy afternoons.
Plan on long leaders, small flies and careful wading, and check the closing date before you go.
Load your fly box
Before you head to Harriman Ranch, bring: PMD Sparkle Dun #16-18, Parachute Adams #16-20, Elk Hair Caddis #16-18, Flav (Drake) Dun #12-14, Trico Spinner #20-22, Zebra Midge #18-22, RS2 Emerger #18-22, JuJu Baetis #18-22, Pheasant Tail Nymph #16-20, Black Beauty #20-24, Egg #14-16, Squirmy Wormie #12-14, Scud Bomb #14-16.
Flies working right now
The flies above that we have in stock right now.
Henrys Fork details
| Access | Harriman State Park off US-20, plus Last Chance and Osborne Bridge access. |
|---|---|
| Elevation | About 6,100 ft |
| Nearest town | Island Park, Idaho |
| Best season | Mid-June through fall |
| Fish | Wild rainbow trout |
| Regulations | Fly-fishing only, catch-and-release, seasonal. Check the Idaho Department of Fish and Game seasons and rules before you go. An Idaho fishing license is required for anglers 14 and older, plus a steelhead or salmon permit where those fish are targeted. |
| Leaders and tippet | 12 to 15 ft leaders, 5X to 7X tippet |
| Camping | Campgrounds around Island Park |
| Kids | Partly. Easy wading but very technical fish. |
| Good to know | Spot a rising fish before you cast. Most anglers wade slowly and fish one riser at a time. |
Fishing by season
Winter
Closed.
Spring
Closed until mid-June.
Summer
PMDs, green drakes, flavs, caddis and tricos.
Fall
Mahogany duns, BWOs and hoppers before the closure.
How to get there
From Ashton, take US-20 north about 20 miles to Harriman State Park.