South Fork of the Boise River
river in Idaho
Below Anderson Ranch Dam, the South Fork of the Boise is a classic tailwater known for its consistent cold water temperatures and prolific insect hatches, leading to excellent dry fly fishing for large, wild rainbow trout. It's a premier destination for those seeking a challenging but rewarding experience.
Conditions right now
No USGS gauge is linked to this water yet, so we can't chart flows.
What's working on South Fork of the Boise River
- 01Consistent fall hatches of Blue-Winged Olives and Mahogany Duns provide dry fly opportunities.
- 02Nymphing with midge and stonefly patterns remains highly effective in deeper runs.
- 03Streamer fishing with leech and baitfish imitations is excellent for targeting larger Rainbow and Bull Trout.
- 04Egg patterns are crucial as trout and salmon spawning activity continues to influence feeding behavior.
- 05Expect improved fishing conditions as summer heat has subsided, offering comfortable fall angling.
What to tie on
Picked from reports, hatches and the season. Tap a fly for the recipe and where else it works.
Blue-Winged Olive (BWO) Comparadun
Fall BWO hatches are active, and this low-profile dry fly is excellent for selective Rainbow Trout feeding on emergers and adults.
Buy at AmazonBlood Dot Egg
Fall is prime egg season for trout below spawning salmon, making this pattern highly effective for both Rainbow and Bull Trout.
Buy at AmazonTravis Hi-Vis BWO Para Emerger
BWO emergers are crucial during fall hatches, and this high-visibility pattern helps spot subtle takes from Rainbow Trout.
Mahogany Dun
Late summer and fall often see hatches of Paraleptophlebia (Mahogany Duns), providing dry fly opportunities for Rainbow Trout.
Buy at AmazonComet
This general attractor streamer is effective in fall and winter for predatory fish, making it a solid choice for Rainbow and Bull Trout.
Buy at AmazonZebra Midge
Midges are a primary and consistent food source in tailwaters year-round, effective for Rainbow Trout when fished deep.
Buy at AmazonTungsten Bead Pat's Rubber Legs
Large stonefly nymphs are present year-round and provide a significant calorie source for both Rainbow and Bull Trout, excellent for getting deep.
Buy at AmazonPine Squirrel Leech (Olive)
Small leech patterns effectively mimic sluggish baitfish and annelids in cold water, enticing strikes from larger, lethargic Rainbow and Bull Trout.
Where to fish and who to ask
Dam to Cow Camp
Access below Anderson Ranch Dam, known for consistent fishing.
Get South Fork of the Boise River reports by email
Save this water and we'll email you a weekly summary of conditions, hatches and what's working.
Idaho season by season
What changes on the water through the year, with the flies for each season.
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Quick answers
Common questions about South Fork of the Boise River.
What flies work best on South Fork of the Boise River?
Our top scored fly patterns for South Fork of the Boise River right now are Blue-Winged Olive (BWO) Comparadun (80% confidence), Blood Dot Egg (80% confidence), Travis Hi-Vis BWO Para Emerger (80% confidence). These picks are scored from recent fishing reports, hatch data, and seasonal patterns.
What fish species are in South Fork of the Boise River?
South Fork of the Boise River holds Whitefish. See the species links on this page for fly recommendations and seasonal behavior for each.
Is South Fork of the Boise River fishing well right now?
We publish a fresh bite report for South Fork of the Boise River each week based on recent on-the-water intel. The current report — with conditions, hatches, and what's producing — is on this page.