Skip to content
Home » Your Streams & Waters » Fly Fishing Report On The South Fork Of The Snake River In Idaho

Fly Fishing Report On The South Fork Of The Snake River In Idaho

South Fork Snake River Idaho Trout

Fly Fishing South Fork Snake River Idaho including a South Fork River fishing report.

Fly and Gear ordering and delivery: We can get flies to you within two to three business days from the time you place your order via Priority Mail. If you provide a budget for flies, we will select them to match the budget and get them to you on time for your trip. Please see the bottom of this column for ordering options.

We also have custom Perfect Fly selections in 3 different price ranges for this stream that come with or without fly boxes. They make excellent gifts. Click Here To Order or Call us at 800 594 4726 or email us at sales@perfectflystore.com.

Species
Rainbow Trout (Wild)
Brown Trout (Wild)
Cutthroat Trout (Native()

Size
Large – 64 miles long

Location
Eastern Idaho

Nearest Towns
Swan Valley

Season
Year-round

Special Regulations:
Yes – Check Current Regulations

Access:
Fair

Non-Resident License
State of Idaho

Weather
National Weather Service Link

Hatch Chart
Perfect Fly Hatch Chart

Fly Fishing Gear and Trout Flies

USGS Stream Flows:
At Irwin
At Heise

Seasons:
Fly fishing the South Fork of the Snake River is good throughout the season but the water levels will vary
considerably.
Spring:
Spring time varies from year to year
depending on the  snowpack but is
usually good for the most part.

Summer:
Summertime is the time when the big stoneflies hatch and the most popular time to fish the river.
Fall:
Fall is the best time for wading anglers to fish.

Recommended Tackle & Gear
Fly Line:
5 or 6 weight
Leaders:
Dry fly: 9 & 12 ft., 5 or 6X, Nymphing:
71/2 ft., 3 or 4X, Streamers 0-2X

Tippets:
Dry fly: 5 or 6X, Nymphing: 3 or 4X,
Streamer 0-2X

Best Fly Rods:
Perfect Fly Superb Five or Ultimate Six
Fly Reels:
For 5/6 fly line
Fly Floatants and Misc Items:
Floatants, KISS Strike Indicators
Tools & Accessories:
Nippers, forceps, retractors, etc.

Fly and Gear ordering and delivery:

Email us  at (sales@perfectflystore.com) with the dates you will be fishing and we will send you a list of our fly recommendations. We can get flies and gear to you within two to three business days from the time you place your order via Priority Mail. If you provide a budget for flies, we will select them to match the budget and get them to you on time for your trip. Your can also call us at 800-594-4726 and we will help you decide what flies and gear to use. All orders are shipped free in the U.S. If under a $100 order requiring Priority mail is a charge of only $8.10. Orders over a $100 are shipped free via Priority Mail.








South Fork Snake River, Idaho Fishing ReportNovember 20, 2024

Stream levels are still flowing below a normal level for this time of the year. Good hatches have been taking place. We update the South Fork Snake River fishing report weekly, so keep checking back with us. We received one good report from a customer fishing yesterday.

Stream Flow Data: 925 cfs

Level: 4.47 ft

Afternoon Water Temperature: 50

Clarity:  clear

USGS Real-Time Stream Flow Data At Irwin

Weather:

SWAN VALLEY WEATHER

Strategies, Techniques and Tips:

Trout Flies:

Midges: Cream and Red (Blood) midges sizes 20/22, larva, pupa and adult. Our larva and pupa midge flies, pre-rigged in tandem, are very popular here. You can fish them under a strike indicator keeping the larva fly near the bottom. https://perfectflystore.com/product/pre-rigged-tandem-midge-larva-pupa-tippet

Brown Sculpin and White Belly Sculpin and Articulated streamers, size 6/4
Black Matuka and Olive Matuka Sculpin, size 4/6

Blue-winged Olives: size 18, nymphs, emergers, duns, spinners

Western Ginger Quills: 14, Nymphs, emergers, duns and spinners

Mahogany Duns, size 18, nymphs, emergers, duns and spinners

October Caddis, size 6, pupa and adults

Perfect Flies are designed and tied to to imitate and behave like the natural foods the trout rely on to survive as much as possible. The more your fly looks like and moves through and on the surface of the water like the real things, the higher your odds of success.

Fly Fishing On The South Fork of the Snake River In Idaho: The South Fork of the Snake River is one of Idaho’s better tailwaters. This is especially true if you like to fish from a drift boat. That is by far the best way to fish the river although it does have some excellent fishing for the wader during the late summer and early fall season. The South Fork of the Snake River flows from Wyoming into the state of Idaho into Palisades Reservoir. The tailwater flows from the Palisades Dam a distance of sixty-four miles to its confluence with the Henry’s Fork. Fly fishing the South Fork of the Snake River ranks at the top of the list of most anglers who have experienced it.Located in south eastern Idaho, is known for its large cutthroat, rainbow and brown trout. It has large hatches of mayflies, caddisflies and stoneflies that provide excellent dry fly fishing opportunities. Many anglers rank it at the top of their list of fine tailwaters. The river has some very large pools and some long fast water riffles and runs. In many areas the river is broken up into braided sections by islands creating a very diverse fishery. Fly fishing the South Fork of the Snake River can be challenging at times, but like any river worth fishing, it’s the challenges that make fishing exciting. The South Fork has a population native Fine Spot and Yellowstone cutthroat trout. In recent years the rainbow trout population has caused some concern because it has grown to the point is has affected the native cutthroat population. The native cutthroat trout attain a very good size with the cutthroats ranging from fourteen up to twenty inches. The brown trout also grow large, commonly exceeding twenty inches. The population of brown trout increase in the lower section of the river. The upper section of the South Fork, approximately half of the part extending from the Palisades Dam to the Conant Valley boat access, is fairly narrow. There are a total of four public boat launches in this area of the river. This section is approximately fifteen miles long. Below the Irwin Access, the river widens out and becomes much shallower. It meanders through the Swan Valley with many side channels and shallow water riffles. There are some of the South Fork’s best wading opportunities in this section. It also provides some of the best dry fly fishing.From there, the South Fork enters a large canyon. It begins at the Conant Valley boat access and extends downstream to the Byington boat access. There are two additional public access in the canyon section of the South Fork – Cottonwood Access and Wolf Access. This section is about fifteen miles long but once you decide to float it, there’s no point to get out of the canyon. There’s no other access points in the canyon. The canyon section is the most beautiful section of the river. It is also the most fun section to fish in our opinion. The water doesn’t normally drop to where wading anglers are not at a disadvantage until the month of September. Autumn is the best time to wade the South Fork. This large tailwater is generally best for float trips. Many  areas are just too deep and swift to wade. Numerous boat and foot access points are found along the South Fork of the Snake River’s length from the dam to Lorenzo near the point it joints the famous Henry’s Fork of the Snake River. When your fishing the South Fork, please always keep in mind that swift currents, deep water, irrigation diversion dams, and other hazardous situations exist. Always exercise caution whether your wading or floating the big river.

Fly Fishing Guide to the South Fork of the Snake River: This is a huge expanse of water with a lot of variables. The fishing methods and strategies vary with the seasons and the water levels. The hatches are not always consistent as to the time they occur. The order in which they occur is consistent but due to variation in water temperatures due to various water releases from the dam, the dates may vary some from year to year. The hatches are usually very large and the trout often feed selectively. The upper part of the river, from the dam down to the Connant Boat Ramp is considered the first or upper section. It is about twelve miles long. The best access for the wading angler is provided from the Forest Service road, also called the Snake River Road. Most of the property on the main highway side or North side of the river is private.The next twenty-four miles of the river is called the “Canyon” section of the South Fork of the Snake. It is broken into two float sections, or the middle and lower sections sometimes called sections two and three. This is a beautiful section of the river with lots of wildlife. The river looks like you are inside a big wilderness area but in reality you are just in a deep canyon below open farm land. The middle section runs from Connant Boat Ramp down to Cotonwood Boat Ramp.  There are several National Forest campgrounds along the way. The lower section runs from Cotonwood Boat Ramp down to Byington Boat Ramp at Ririe. Either one of these two float sections provides a good day of fishing. The lower section or the river, or section four, runs from the Byington Boat Ramp down to the rivers confluence with the Henry’s Fork of the Snake. The Lorenzo Boat Ramp is the usual takeout point, but you can fish even farther downstream to the Henry’s Fork. This section flows through farm country that is much flatter than the upper areas.

South Fork of the Snake River Hatches and Trout Flies: Our information on aquatic insects is based on our stream samples of larvae and nymphs, not guess work. We base fly suggestions on imitating the most plentiful and most available insects and other foods at the particular time you are fishing. Unlike the generic fly shop trout flies, we have specific imitations of all the insects in the South Fork Snake River and in all stages of life that are applicable to fishing. If you want to fish better, more realistic trout flies, have a much higher degree of success, give us a call.  We not only will help you with selections, you will learn why, after trying Perfect Flies, 92% of the thousands of our customers will use nothing else. 1-800-594-4726 Hatches on the South Fork of the Snake River are different from many tailwaters. Some of the insects, like the large stoneflies, hatch in huge numbers. Hatches occur throughout much of the year. In order to fish the South Fork successfully and consistently, you must be able to keep up with and match the hatches.The first hatch of the year are the Blue-winged Olives. They start about the first of March and last through April. There is a second hatch that occurs about the first of September and last on into October. Since the water is usually low during this period of time, the second hatch can be a good one to fish. March Browns also hatch from about the middle of March through April. The last week of April through the month of May, you will usually find the Grannom (Branchycentrus species) caddis hatching. This hatch is called the Mother’s Day hatch in some areas. The most abundant hatches of caddisflies are different species of Spotted Sedges. They hatch during July, August and the first part of September. Their Little Sister Caddisflies also hatch from about the middle of August into September. The final major caddisfly hatch is the October Caddis which hatches during September and October. There are several other minor hatches of caddisflies but these are the most important ones. There is a Skwala Stonefly hatch that occurs from about the middle of April through May. The huge Salmonflies, a hatch most anglers consider the highlight of the year on the South Fork, start hatching near the end of June. It is usually at its peak the first two weeks of July. Don’t forget the terrestrials. The farming areas surrounding the river tends to increase what would be a normal population of grasshopper, ants and beetles into large populations of these land based insects. Imitations of them can be very effective during June, July, August and September. As with most any tailwater, midges hatch in huge quantities and for many days of the year. They are often ignored on the South Fork because of the numerous other hatches, but imitations of the larvae, pupae and adults will catch fish almost any day of the year.Some of the most popular flies are streamers. They work great in fooling the larger brown and cutthroat trout. Imitations of sculpin, minnows and baitfish are very effective at times. They work great during high water conditions and during the fall when the brown trout spawn. We recommend our “Perfect Flies” not just because we sell them. We recommend them because we feel they are the best trout flies you can purchase. Our stonefly imitatons are very realistic and very effective.  We have specific caddisflies and mayfly imitations of every species that hatches on the South Fork of the Snake River. If you haven’t done so already, please give them a try. We guarantee you will be satisfied.  The Golden Stoneflies start about the same time, or maybe a week later than the Salmonflies, but last a little longer on through the month of July. The Little Yellow Stoneflies, often called Yellow Sallies, are almost overlooked because of the larger ones. They hatch from about the first of July through August and into the month of September. The Pale Morning Duns represent one of it not the best hatch of the year. These little mayflies hatch from about the middle of June through August. Mahogany Duns hatch from about the first of August through the month of September, extending the mayfly hatches for almost another month. From the middle of June into July you may find a hatch of the Great Olive Winged Drakes. They hatch on the more moderate sections in the lower part of the river.

Stream Report Archive: 01/22/2020 The stream levels are just a little below normal but in good shape. We continue to get good reports from customers. Our articulated sculphin patterns are catching some large trout. There are still good Blue-winged olive, Blood and cream midge hatches among others.
02/24/2020 The river is flowing at a normal level. Fish as near the dam as legal. The water
is warmer there than anywhere else. There are some hatches taking place and we are
gettng some good reports.
03/19/20 Discharges and stream levels are high, too high to fish in our opinion. We do think they will lower the discharges soon and the river will be in good shape. The weather and water should be getting a little warmer.
04/26/2 The discharges and resulting stream flows are very high. There are some hatches
taking place and with the warmer weather coming, there should be many more on the way.
05/14/20 Discharges and stream levels continue to be very high. There is rain everyday for
the coming week after today. Fish as soon as it drops back down.
05/28/20 Discharges and the resulting stream levels are still high and that is normal at this time of the year. They will be dropping soon and that is the time you should be on the river. Now is the time to get prepared with your gear and flies. Shoot us an email.
06/06/20 The discharges and resulting stream levels are extremely high, too high to fish.
Now is the time to get your gear and flies together for the upcoming good opportunity.
06/19/20 The river is still very high and stained, too high to fish. Hopefully the runoff
conditions will end soon.
06/29/20 The discharges and stream levels are still very high, too high to fish.
07/12/20 Conditions are good. The discharges and stream levels are down to a normal level and we are starting to get some good reports. There are several hatches but vary with the section of the river being fished.
07/28/2 Conditions are very good. There are a lot of insects hatching. They vary with the
section of the river being fished. We ae getting some very good reports from customers. This coming week should be another good one.
08/16/20 The river is in good shape with the discharges and resulting stream levels at a
normal level. We continue ot get good reports form customers fising the river. All sections are urning out good numbers of trout
09/04/20 The river is in good shape. The discharges and resulting stream levels are just a little above normal and the water clear. We continue to get some good reports from customers. All sections of the tailwater are turning out fish.
09/24/29 The discharges and stream levels are in good shape and we continue to get some very good reports from customers. There are still plenty hatching insects and our sculpin streamers are catching some big trout.
10/30/20 The river is in good shape flowing just a little below a normal level for this time of the season. We continue to get good reports from customers. Our articulated streamer patterns are catching some nice trout.
Note: We are no longer posting the archive reports due to the number
we already have.