South Fork

South Fork 7-9-10

From Bryce Oldemeyer, South Fork Initiative Project Manager, HFF: Discharge from Palisades Dam was reduced 1,000 cfs this afternoon (7/8, 2pm) and will be reduced another 1,000 cfs tonight. Discharge from Palisades Dam will be 13,300 cfs tomorrow morning. Dependent on irrigation demand, small decreases to Palisades Dam discharge may be made later this week.

Riffle fishing from PMD and yellow sally activity offers best action by early afternoons.  Beforehand use your favorite small beadhead nymph patterns there.  Rubberleg patterns may also work here during the early hours. Stonefly hatch is below Cottonwood and has been doing a great job of taking boats from the lower Henry’s Fork.  Don’t forget the tip of slowing down your boat and pitching super renegade patterns underneath or just in front of  overhangs and retrieving as you drift on by!

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South Fork 7-6-19

Stoneflies are out up to Byington. Action begins during  afternoons.  Fish seem just as interested, for now, in sallies and mayflies. Try for these around riffles. Rubberlegs still work and so do super-X’s presented from out in stream towards banks.  Cast  super-x’s towards overhangs, then pull back into the river, or just let them drift  by overhanging vegetation.  Flow out of Palisades Dam has been raised a bit (to 1480 cfs) from Jackson Lake output.  In several days, look for flow to be ramped back to normal for this time of year

South Fork 7-2-19

Palisades Reservoir is at full capacity, and in-flow is dropping.  Flow out of Palisades has been raised some in the last week. Now is 14000 cfs  (about the same at Heise, 7160 cfs at Lorenzo), which is  a bit above normal.

PMDs, green drakes and yellow sallies are emerging  upstream to Cottonwood making for improving dry fly fishing. Presenting flies around riffles is best strategy for doing so.  Big stoneflies are emerging up to Byington, but fish are just beginning to key on them. Rubber legs and streamers still working.

Fishing interest here is still well below that on the Henry’s Fork, but as fish become more interested in big stoneflies, look for boating crowds to appear.

South Fork 6-25-19

It’s about ready to turn on the big stonefly hatch on. A few stoneflies are flying on the river below Lorenzo, and any day the fish will begin to notice. Warm weather coming up means their emergence will soon march up the river providing exciting dry fly fishing and crowds. Right now there are not many folks fly-fishing here, even though flow out Palisades Dam ( reservoir is about 95% of capacity and bulk of run-off is over) is about normal for the time of year.  This makes the South Fork a great alternative to fishing the crowded lower Henry’s Fork. A few early season sallies are showing up. For now streamers, a variety of nymphs with and without beads, rubber legs, and big stonefly nymph patterns provide best action especially around riffles and side channels.

South Fork 6-22-19

Here is some useful technical information on the South Fork from Bryce Oldenmeyer of the Henry’s Fork Foundation.

Flow update: In response to cooling temperatures and decreased inflow, discharge from Palisades Dam was decreased 2,400 cfs this (Friday, 6/21) afternoon. Current outflow from Palisades Dam is 11,400 cfs. Flows are expected to stay around this level for the next 7 to 10 days.

Snow and reservoir overview

Average temperatures the last seven days have melted most of the snow at sites above Palisades Reservoir. Out of the eighteen SNOTEL sites above Palisades Reservoir, Togwotee Pass (elevation 9580 ft) and Two Ocean Plateau (elevation 9240 ft) are the only SNOTEL sites with snow. Togwotee Pass has 8.1 inches SWE (92% of median for the date; 32% of peak) and Two Oceans Plateau has 7.8 inches of SWE (66% of median for the date; 26% of peak SWE). Cooler temperatures are forecast for the next 3-4 days and runoff is anticipated to slow over the weekend. Even after temperatures are expected to return to average next week, it is likely that runoff will continue to decline as the remaining snow proceeds to melt.

The Upper Snake River system is currently 96% of capacity and expected to fill by the end of the month. Palisades Reservoir is 95% full (1,139,623 ac-ft of 1,200,000 ac-ft) and Jackson Lake is 97% full (822,279 ac-ft of 847,000 ac-ft).

With respect to fly-fishing, giant stoneflies are beginning to emerge along the river below Lorenzo. With warming weather they will soon advance up the river and become numerous enough to interest resident trout.

South Fork 6-18-19

Palisades Reservoir is at 85% of capacity.   With plenty of snow remaining in the mountains above, full capacity is not far away.  How this impacts flows in the river will be set by the Bureau of Reclamation, but we will report here on what happens.

South Fork 6-15-19

Over the past few days the flow out of Palisades Dam has been raised to current 13700 cfs   (14200 cfs at Heise, 6900 cfs at Lorenzo) which is almost normal flow for this date.  Palisades Reservoir is at 85% of capacity, and a ton of snow remains in the mountains above it. So expect more flow increases to come.  Meanwhile, stay with the fly pattern strategy we have suggested in recent fishing reports.

South Fork 6-11-19

Flow out of Palisades Dam was raised to 11700 cfs yesterday ( now 12500 cfs at Heise, 4950 cfs at Lorenzo). This brings flow in the river to near normal for this time of the season.  Use same strategy as we suggested in last report: streamer patterns or rubber legs with San Juan worm or small bead head dropper.  You will see A LOT fewer anglers on the river compared to the crowds on the Henry’s Fork.

South Fork 6-8-19

Flow out of Palisades Dam is about 8900 cfs  (10200 cfs at Heise,  3340 cfs at Lorenzo)  and looks to be at that level for a while. Palisades Reservoir is about 65% full. Compared to the fishing pressure currently on the Henry’s Fork, there is very little here, and fishing is quite good up and down the river.    Streamers work well when presented over drop-offs.  Rubber legs seem to bring the most action and do even better when trailed by a San Juan Worm or small bead head nymph.  No really good top water action yet, but a few riffles do have some BWO activity.

South Fork 5-21-19

No significant changes in flow here. Same with fishing suggestions ( See May 14 web site fishing report). Palisades reservoir is slowly filling, now about 56% of capacity.