Henry's Fork Report - August 3, 2023

Henry’s Fork Streamflows

Island Park Dam:  1260 cfs

Ashton Dam:  2020 cfs

St. Anthony:  1090 cfs

Fall River:  285 cfs

This last week in Henry’s Fork country has been a good one not to miss.  It has been several years since we have seen this kind of water clarity with solid spinner falls lasting through the month of July.  The water situation looks fairly stable at the moment, with irrigation demand in the early stages of waning, slightly lower flows out of Island Park Dam are reflecting this.  Clarity is the wild card, but at the moment we are hopeful this stretch of low turbidity will continue.  Things are likely to begin to slow down in the coming week, but this is not a certainty, lots of clouds and cooler weather in the next 10 days forecast, which could definitely keep those hatches coming.  PMD and remnant Flav hatches could benefit from the forecasted cloud cover.

Box Canyon

The Box remains at a comfortable flow at just over 1250 cfs, it’s moving right along in there and is still prime for a full day endeavor or an afternoon dry fly run.  Golden Stones have been present in good numbers, but the cooler weather to come may start to put an end to the large dry fly opportunity.  Dry fly runs have been just good enough to cut out the dropper portion of the dry/dropper rigs and it’s worth considering that the trout respond better to the Golden imitations when there sin’t a bead head hanging underneath at times.  Otherwise, indicator nymphing rigs are the standard choice and a variety of flies have been working.  Bug activity is generally limited to midges, caddis, PMDs and Flavs, and even Baetis aren’t out of the question with the forecast.  A variety of split shot is helpful, we like to keep B’s, BBs and ABs all on hand.  Solid choices for flies include:  red and brown Zebra Midges 14-18, PTs 14-18, R/L Tactical PTs 14-16, Split Backs 14-18, SH Hare’s Ears and Hare/Copper 14-18, Hungarian Partridge Caddis Pupa 14-16, Rubberlegs Stonefly nymphs 8-12, and your favorite perdigons (Bullet Quills, Spanish Bullets, Jig Napoleons, Hollowpoints 14-16 and Jake’s SH 16-18).

Railroad Ranch

This past month has been a treat on the Ranch, with days ranging from sparse hatches to bug soup, but consistently with hungry trout feeding.  Spinners have been the name of the game for the most part, nothing like approaching a rising trout with the knowledge that it’s dining on something you can imitate perfectly with your fly.  We have been fishing with confidence out there and the rewards have been there.  This is in stark contrast to fishing to trout in emerger situations, which are likely around the corner, characterized by lots of fly changes and repeated presentations.  Things are going to get trickier soon!  One thing to keep in mind is that many of the trout in the Ranch are moving targets, feeding regularly but roaming while they do so.  A little observation can go a long way if the trout reveals its pattern, successful Ranch anglers know to try and present the fly to where the trout is likely to be, not where it was on its last rise.  I like to have some line out and am ready to cast while in the approach to targets such as these, opportunities present themselves unexpectedly and anglers who are ready and capable of placing their fly in the right spot quickly will reap bonus rewards.  Be on the lookout for spinner falls in the morning, generally PMD and Flav spinners in rusty, cream, and olive 14-18.  For PMD emergences, keep some Last Chance Cripples, CDC Captive Duns, CDC Biot Duns  and a Heames Klinkhammer handy 16-18.   Being prepared for Flav hatches consists of having some CDC Biot Duns, Captive Duns, Variant Cripples 14-16 handy.  Most of us wouldn’t be out there without a handful of flying ant patterns as well, we are now in the season and expect to see them on any given day.  Harrop’s Honey Ant 14-16, Harrop’s Black Flying Ant 18, and a Heames Honey Ant 14 will ensure you are prepared for such opportunities.

Canyon Country

The Canyons of the Fork remain a great place to find some solitude and enjoy a wilderness experience.  Fishing has been consistently solid.  Dry/Dropper rigs are the norm, but it’s always good to have some indicators and split shot handy should you want to pull over and spend some time on a likely run or piece of water.  This is also a good time of year to throw streamers for those so inclined, this year’s crop of juvenile trout are coming into a size that is best imitated with a size 4 or 6 Bouface Leech, Copper or Olive Zonker, and the venerable BFE (Best. Fly. Ever. Now available with tungsten eyes and in mini sizes!).  Keep in mind that skillful oarsmanship is a must and usually a raft is the right choice of watercraft.  Bring rain gear, regardless of what the sky looks like when you start in the morning, weather moves in quickly in the canyons.

Warm River to Ashton

This section has been consistently producing quality trout fishing for anglers of all skill levels, and is likely to benefit from a little cooler weather in the coming week.  Choose your own adventure here: Dry/Dropper and indicator nymphing rigs are both in order, usually you’ll need something to fish subsurface here, though rolling a small golden stone may produce a few quality surprises.  Streamers are a great bet as well.  Fly selection about the same as the Box Canyon.

Below Ashton Dam

With water temperatures having hit what is likely to be their highest this summer in the past week, things have slowed down to almost un fishable outside of an early morning foray.  Most anglers’ time will be better spent focusing on the waters upstream of Ashton Reservoir at this time. 

Get out there and good luck!