Henry's Fork Report - July 24, 2025

Henry’s Fork Streamflows

Island Park Dam:  1060 cfs

Ashton Dam:  1830 cfs

St. Anthony:  1040 cfs

Fall River:  202 cfs

Beautiful days with a variety of fishing conditions ranging from difficult to good is the word on the Henry’s Fork at the moment.  High flows are on the decrease in the upper river, trending quickly towards opportunity.  Nice weather, a few more rising fish, and a busy weekend in Island Park are in the near forecast.  Lots of partly cloudy days looking forward with occasional afternoon showers are in the long term, so bring your sunblock and your rain jackets!  Water quality is generally good throughout the river, with water temperatures below 70 degrees throughout the system, except for the lower river stretches around St. Anthony on occasion.  Turbidity is variable, some days a bit more murky than others, but generally well within the range of what we consider fishable.  The splash and giggle crowd will be out in full force this weekend, so bring your throwbags, first aid kits, and a little extra patience while the odd floatilla comes through the Box Canyon and Warm River to Ashton stretches. 

Box Canyon

The Box is decreasing in flow, not drastically at the moment, but is coming into fine shape.  At these flows the float is generally not too bumpy and the character of the river more easily read than when it is higher.  If water clarity is lacking at the top of the canyon, it usually improves after a ½ mile or so of the float.  High enough to require B and BB split shot at times and low enough to fish without splitshot at others, matching your rigging to the depth of water you’re fishing will be important.  At times of high turbidity, considering using flies with hot spots or fluorescent accents, and when the river is a bit more clear, something small and red can be a good choice.  Golden Stoneflies are around in good number and the bite will vary from hour to hour, so a dry fly or dry/dropper run is a worthy endeavor and makes a great shorter float.  It’s hard to beat a Lawson’s Golden Stone or Waterwalker #6-10, Jojo’s Golden Stone is a great add in the same sizes.  Indicator rigs are still the bread and butter but streamers are worth a shot as well, especially during periods of lower light.  Nymphs we’re happy to keep well-stocked and in our boxes are:  PTs, R/L Tactical PTs, Olive HP Caddis Pupa, Rednecks #14-16, red and brown Zebra Midges #14-18, black Zebra Midges #18-20, Rubberlegs #8-12, red and claret SJWs #12-14.  For perdigons, we are liking the Olive Hot Spot, Spanish Bullet, Bullet Quill, Firestarter, Blowtorch, PMD Frenchie, and the Black Dagger #14-18.  Good streamer choices are Olive, Black and White BSA Boufaces #6 and 10, Olive/Black BFEs #4, and Zonkers in both copper and olive #6-8.  If the tubers come through in large numbers, remember that pulling over for a few minutes usually gives them time to disappear from sight and mind in this fast-flowing stretch of water.

Railroad Ranch

As forecasted, the last week has been pretty gloomy on the Ranch with flows that were nearing 2000 cfs.  We’ve seen the river dropping and it is now coming close to being in shape enough for its resident trout to begin to look to the surface for their food.  This is likely to be a slowly progressing trend but we are hopeful this week will bring a few more noses to the surface and some increase in dry fly opportunity.  There are bugs around through most of the morning hours, sparsely through the afternoons.  Spinners of multiple sizes and colors are on the menu and anglers will want to have several colors and profiles in sizes #14-20.  Tricos, PMDs, Flavs, Callibaetis, Caddis, Gray Drakes, midges, flying ants, hoppers and beetles are all on the menu in relatively sparse quantities.  Find the food lanes and be prepared to put some searching time in between targets.  A variety of flies may be necessary, so be ready for what you might find out there.  We like Harrop’s Paraspinners and CDC Biot spinners, Copenhaver Spinners, Barret’s Flav spinner and Hackle Stackers in cream and rusty #14-20, and black #18-20.  Harrop’s Honey Ant, Shimazaki Ant, and Heames’ Honey Ant will cover you for the Hymenoptera species, while a variety of hopper patterns may produce results as well in the Arthropod department.  Observation is a super power in this pursuit of flyfishing, take your time to notice the small things that may yield large results.  A day on the Railroad Ranch in relative solitude when there is hope on the horizon is a day well spent, regardless of the outcome. 

Canyon Country

Decreasing flows mean a few more places anglers can pull over and work the water in these reaches.  These waters are getting close to having more character and being more easily plied.  Dry/dropper rigs reign supreme in here, but indicator nymphing rigs and streamer set ups have their places.  A golden stone imitation on top and a rubberlegs or other stonefly nymph variety will usually do the trick, but many bead heads will work as well if the stonefly bite is stubborn.  Good populations of mayflies and caddis in these reaches so have fun and experiment along the way!  For streamers, we like BFEs, Boufaces, and copper Zonkers, leeches and SJWs are a good add as well.  This is raft country and good oarsmanship is a must, but these reaches can help anglers find a bit of solitude during otherwise busy times out there.

Warm River to Ashton

This section of river has been entertaining anglers for the past month and promises to do so for the next as well.  Higher flows that are decreasing now will reduce bank opportunities and have trout retreating to the comfort of slightly deeper water.  Keep your efforts focused on the transitions.  Dry flies, Dry/Droppers, and Streamer rigs can all be useful here this week, employing different techniques throughout the day can produce results of different calibers.  Flies selections should mirror that of the Box Canyon. 

Below Ashton Reservoir

Limited opportunities in these waters with relatively high flows and low numbers of hatches.  We are still generally leaving these sections alone until water temps cool and nights shorten a bit more.  Mornings can provide some fishing pleasures, but afternoon temperatures will slow things down on most days in these lower river reaches. 

Get out there and have fun!