Wade4/100
Wading is the most sensitive plan today. Use protected edges only, avoid crossings, and downgrade quickly if clarity or current feels wrong.
All Idaho reports
Fly fishing report · West
South Fork of the Boise River Fishing Report — Idaho
Is South Fork of the Boise River worth the trip today? Check flow, weather, hatches, access, and rules for Idaho before you go.
See the flow chart ↓Photo: Charles Knowles from Meridian Idaho, USA Opens in a new tab. · CC BY 2.0
Good day to fish?Latest river check
Poor
Not today. Make another plan.
39
Best option: Float. A float can fit better than wading only if launches, shuttle, boat skill, wind, and local rules all check out.
See update time and confidence
Live data checkHighHow much of the live flow, weather, and alert data came back.
Today's callHighA verified hard stop is active, so the avoid-or-wait decision is clearer than the fishing score itself.
Score calculated Aug 22, 2026, 8:39 PM MDTUsually checks again about every 45 minutes
Best access methodFloat
These scores compare the risks of wading, bank fishing, and floating.
Bank / edgeNot recommended
This report does not recommend bank fishing on this reach.
Float · Best fit19/100
A float can fit better than wading only if launches, shuttle, boat skill, wind, and local rules all check out.
Red Flag Warning issued August 22 at 3:59PM MDT until August 23 at 12:00AM MDT by NWS Boise ID
Your plan
Today's South Fork of the Boise River plan.
The South Fork Boise is a strong tailwater trout fishery, but the plan changes with Anderson Ranch releases and IDFG special rules. Confirm the reach is open, then match tactics to safe wading or floating flows.
- Check first
- Use the Anderson Ranch Dam gauge before committing to wade or float.
- Try
- Check the Anderson Ranch release before choosing a wade plan.
- Leave when
- Skip the trip when seasonal closures or Neal Bridge reach rules are unclear, when releases make wading unsafe, when canyon roads or weather make access risky, or when crowding concentrates anglers into a few legal pullouts.
Live river check
What the river is doing
Check the latest flow and weather before you go. A quick change can make the river harder or less safe to fish.
Showing the latest stored river check while current readings load.
- Flow
- 799 cfs
- From the latest stored river check. Open the official source for the newest reading.Water 50.5°F · 24h high 52.2°F · USGS provisional
- Air now
- 87°F
Current NWS forecast period
- Next 24h high
- 87.0°F
NWS air forecast near
- Rain chance
- 31%
For this forecast period
Latest stored weather check
Scattered Showers And Thunderstorms
Scattered Showers And Thunderstorms
- Wind
- 5 mph
- Weather checked
Recent flow chart is loading
The latest stored reading is shown above. Check the official source below if you need the newest value now.
More forecast and source details
National Weather Service
South Fork Boise Anderson Ranch forecast point
The National Weather Service forecast is temporarily unavailable.
Live data
Where these readings come from
RiverReports gauge: South Fork Boise River below Anderson Ranch Dam
Water 50.5°F · provisional · 24h high 52.2°F provisionalWater observed · high observed
How to fish it
How to fish South Fork of the Boise River today.
The South Fork Boise fishes best when releases are stable and the legal season supports the reach you want. If flows are high or the reach is closed, use a nearby open alternative.
Moderate stable release
Best for wade plans, nymphs, dry-droppers, and tactical bank work.
High release
Avoid deep wading and consider boat-only tactics where legal and safe.
Low clear water
Use lighter tippet, smaller nymphs, and careful approach angles.
Hot canyon day
Fish early, carry water, and watch trout handling temperatures.
Fishing words used on this page
- U.S. Geological Survey (USGS) gauge
- A USGS gauge is an official river station that measures flow or water height.
- Cubic feet per second (cfs)
- Cubic feet per second, or cfs, shows how much water passes the gauge each second.
- Technical fishing
- Technical fishing means the fish are hard to fool, so careful casts and natural drifts matter.
- Nymph
- A nymph is a young water insect. Anglers also use the word for a fly that copies it.
- Blue-winged olive (BWO)
- Blue-winged olives, or BWOs, are small mayflies that often hatch in cool or cloudy weather.
- Caddis
- Caddis are small water insects. The adults look a little like tiny moths.
- Emerger
- An emerger copies an insect as it rises from below the water toward the surface.
- Midge
- Midges are tiny flies and a common trout food, especially in cold water.
- Pale morning dun (PMD)
- Pale morning duns, or PMDs, are light-colored mayflies that often hatch in warmer months.
- Tailwater
- A tailwater is a river below a dam, where releases can change the flow quickly.
Why this call
Why this score
Public alertHurts
An active alert is in effect: Red Flag Warning issued August 22 at 3:59PM MDT until August 23 at 12:00AM MDT by NWS Boise ID. Check public safety sources before going.
Best mode nowHurts
Float: A float can fit better than wading only if launches, shuttle, boat skill, wind, and local rules all check out.
Short-term weatherUse caution
The forecast has storm or heavy-precipitation risk, so timing and access matter more than the score alone.
FlowHelps
USGS shows 799 cfs. The flow has been stable over about 6 hours. USGS marks this reading provisional and may revise it. USGS records for this date (1943-2025, 83 readings) show a typical middle range of 595 cfs to 1,510 cfs. Flow is within the typical range for this date, so weather, temperature, and access become the next checks.
SeasonHelps
Summer: PMDs, caddis, stones, and hoppers can be strong when releases are friendly.
Trip notes
Trip notes
Check these before you choose a reach.
Use the RiverReports Anderson Ranch chart and USGS 13190500 together. Stable releases create the best technical window. Sudden changes, very high water, or low clear water should change the reach, method, or destination.
Skip the trip when seasonal closures or Neal Bridge reach rules are unclear, when releases make wading unsafe, when canyon roads or weather make access risky, or when crowding concentrates anglers into a few legal pullouts.
Start with the Anderson Ranch release and the exact legal reach, then decide whether the day fits short wade sessions, a canyon scout, or a boat-supported plan. Bring a backup because access and flows can turn a long drive into a poor trade quickly.
If the South Fork Boise is closed, high, crowded, or access-limited, compare the Boise River, Big Wood River, or Silver Creek after checking current rules, flows, and weather.
What to try
South Fork of the Boise River flies through the year.
Match the time of year, then let rising fish and current speed guide the next change.
SeasonWhat to look forFlies to try
Spring
What to look forMidges, BWOs, early caddis
Early summer
What to look forPMDs, caddis, golden stones
Late summerCurrent
What to look forHoppers, ants, caddis
Fall
What to look forBWOs, midges, October caddis
Each fly name opens its matching Fly Box guide.
Access and safety
South Fork of the Boise River access and rules.
Use these places as starting points. Open the access link below and check posted signs before you park or enter. IDFG lists special South Fork Boise rules for the Neal Bridge to Anderson Ranch Dam reach, including seasonal closure and tackle restrictions. Verify before fishing.
Anderson Ranch Dam
The release point and flow-reference anchor for this report.
Neal Bridge reach
Special-rule water that needs current IDFG rule checks.
Danskin and canyon access
Popular public access with road, sanitation, and spacing concerns.
Downstream canyon water
More remote planning with limited services and harder exits.
The roaded canyon can feel easy until weather, heat, or crowds change the day.
Use official rules for seasonal closures and legal tackle.
High releases can make familiar crossings unsafe.
Keep human waste and trash planning part of the trip.
River sources
Official South Fork of the Boise River sources.
Official agencies and primary river operators come first. Secondary tools are labeled so you know what carries the most weight.
How this report was checked
How this report was checked
Reviewed byBlueStreamFly River Review Team
Trip guidance checked
What was checked: This South Fork Boise report is maintained from RiverReports and USGS flow data, Idaho Fish and Game rule sources, public recreation access guidance, weather checks, and Anderson Ranch tailwater planning guidance.
Live measurements and forecasts keep their provider timestamps. Rules, access, and trip guidance use the source-review date shown here. BlueStreamFly planning advice is editorial interpretation, not an agency notice.
First-hand experience: BlueStreamFly does not claim a first-hand visit or local field test for this report unless a real contributor is explicitly named and linked.
Rules and closures
Check what is allowed, where the rule applies, and whether the river is open.
Flow and weather
Check the latest river reading and forecast before you leave.
Access and land
Check public entry points, land rules, and seasonal access changes.
See all 6 checked sources
Rules and closures
Check what is allowed, where the rule applies, and whether the river is open.
What this source covers
Open the current rules and check the river section, season, and special limits.
What this source covers
Open the current rules and check the river section, season, and special limits.
Flow and weather
Check the latest river reading and forecast before you leave.
What this source covers
Open this page and check the latest safety advice before your trip.
What this source covers
Open this river reading to check the latest level, flow, and update time.
What this source covers
Open this river reading to check the latest level, flow, and update time.
Access and land
Check public entry points, land rules, and seasonal access changes.
What this source covers
Open the land or access page, then check signs before you park or enter.
Quick answers
Quick South Fork of the Boise River answers.
Which South Fork Boise gauge should I use?
Use USGS 13190500 below Anderson Ranch Dam, shown with RiverReports and official USGS context.
Are there seasonal closures?
Yes. IDFG lists special seasonal rules for the Neal Bridge to Anderson Ranch Dam reach.
Is this the same as the Boise River in town?
No. This is the South Fork tailwater below Anderson Ranch Dam, not the Greenbelt river through Boise.
Can I wade it safely?
Only at safe releases and legal access points. High releases can make wading dangerous.