Wade69/100
Wading is in play only where your chosen access has clear footing, legal entry, and no forced crossings.
All Michigan reports
Fly fishing report · Midwest
Au Sable River South Branch
Is Au Sable River South Branch worth the trip today? Check flow, weather, hatches, access, and rules for Michigan before you go.
See the flow chart ↓Photo: DawnBreaksOverMarblehead Opens in a new tab. · CC BY-SA 4.0
Good day to fish?Latest river check
Caution
Maybe. Read the cautions first.
69
No clear best access mode. Wade and Bank / edge have the same top score. Use current access, footing, weather, and local rules to choose.
Update time and confidence
Live data checkHighHow much of the live flow, weather, and alert data came back.
Today's callMediumThe river-specific scoring profile still needs deeper review.
Score calculated Aug 29, 2026, 10:57 PM EDTUsually checks again about every 45 minutes
Access choicesNo clear best mode
Wade and Bank / edge have the same top score. Use current access, footing, weather, and local rules to choose.
Bank / edge69/100
Bank and edge fishing remains a practical low-commitment option if access is legal and footing is safe.
FloatNot recommended
This report does not recommend floating this reach.
Your plan
Today's Au Sable River South Branch plan.
The South Branch is its own fly-fishing decision. Start with USGS 04135700 for discharge and temperature, decide whether you are fishing the public Mason Tract water above Smith Bridge or a legally confirmed downstream access, and read Michigan's exact rule section before tying on a fly.
- Check first
- USGS 04135700 near Luzerne is the exact live flow and temperature source for this page.
- Try
- Use the exact South Branch flow and temperature rather than main river Au Sable conditions.
- Leave when
- Skip or change targets for warm water, rising flow, lightning, fire restriction, uncertain bank access, or an unclear rule boundary.
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 server-checked river conditions while current readings refresh.
- Flow
- 131 cfs
- From the latest stored river check. Open the official source for the newest reading.Water 61.2°F · 24h high 61.9°F · USGS provisional
- Air now
- 66°F
Current NWS forecast period
- Next 24h high
- 72.0°F
NWS air forecast near
- Rain chance
- 63%
For this forecast period
Latest stored weather check
Chance Rain Showers
Chance Rain Showers
- Wind
- 0 mph
- Weather checked
RiverReports preview · current series loading
Recent flow
RiverReports gauge
Showing the available RiverReports chart while the current structured flow series loads. Check the chart on RiverReports Opens in a new tab.
More forecast and source details
National Weather Service
South Branch Au Sable near Luzerne
The National Weather Service forecast is temporarily unavailable.
Live data
Where these readings come from
RiverReports gauge: South Branch Au Sable River near Luzerne
Water 61.2°F · provisional · 24h high 61.9°F provisionalWater observed · high observed
How to fish it
How to fish Au Sable River South Branch today.
Stable discharge, trout-safe temperature, and a clearly legal Mason Tract entry create the best dry-fly, soft-hackle, and streamer plan. Warm water or unclear downstream bank access should shorten the session or move it to another reach.
Stable and cool
Fish dries, soft hackles, and light nymph rigs through bends, riffles, and wood edges.
Rising or stained
Work safe near-bank cover with streamers. Do not force crossings through unfamiliar deep water.
Low clear water
Use a quiet approach, long leaders, and low-light windows.
Warm water
Use the live temperature feed and stop targeting trout when safe release is doubtful.
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.
- Nymph
- A nymph is a young water insect. Anglers also use the word for a fly that copies it.
- Riffle
- A riffle is shallow, fast water broken by rocks.
- 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.
- Soft hackle
- A soft-hackle fly has moving fibers that can look like an insect rising through the water.
- Stained water
- Stained water is darker or cloudier after rain, runoff, or a change in flow.
Why this call
Why this score
Local scoring depthUse caution
This page is using baseline river-specific guidance while deeper local scoring is still being reviewed. Use the live sources and local checks before relying on the rating.
Best mode nowUse caution
Wade: Wading is in play only where your chosen access has clear footing, legal entry, and no forced crossings.
FlowHelps
USGS shows 131 cfs. The flow has been stable over about 6 hours. USGS marks this reading provisional and may revise it. USGS records for this date (1967-2025, 58 readings) show a typical middle range of 116 cfs to 151 cfs. Flow is within the typical range for this date, so weather, temperature, and access become the next checks.
SeasonHelps
Late summer: Terrestrials and low-light fishing are possible, but temperature is the first decision.
Water temperatureHelps
USGS water temperature is about 61.2F, and the rolling 24-hour high did not trigger a heat caution. USGS marks the temperature data provisional and may revise it.
Trip notes
Trip notes
Check these before you choose a reach.
Favor a stable discharge with trout-safe temperature and visible edges at the access. The exact number matters less than trend, depth, and safe crossings.
Skip or change targets for warm water, rising flow, lightning, fire restriction, uncertain bank access, or an unclear rule boundary.
Start inside the public Mason Tract area, check flow and temperature, and choose one bridge-bounded section before the evening hatch window.
Use the main branch, Rifle, or Upper Manistee only after checking each destination's own temperature and rule status.
What to try
Au Sable River South Branch 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
April to May
What to look forMidges, early mayflies, caddis, and small stoneflies
Late May to June
What to look forSulphurs, caddis, and historically documented brown drakes
Flies to try
Also try brown drake emerger
Late June to July
What to look forHistorically documented Hexagenia, caddis, and evening mayflies
Flies to try
Also try Hex emerger, Hex spinner
Late summer to fallCurrent
What to look forTerrestrials, small olives, and baitfish movement
Each fly name opens its matching Fly Box guide.
Access and safety
Au Sable River South Branch access and rules.
Use these places as starting points. Open the access link below and check posted signs before you park or enter. Michigan's 2026 rules identify artificial-flies-only rules and different possession provisions by South Branch reach. The current rule PDF, trout map, posted signs, and emergency orders are the legal authority. Verify Chase Bridge, Lower High Banks, Smith Bridge, and main river boundaries before fishing.
Chase Bridge and upper Mason Tract
A named orientation point for the public area and the start of a distinct 2026 rule section.
Mason Tract between Chase and Smith bridges
The clearest official public-water context for a walk-and-wade South Branch plan.
Smith Bridge boundary
Below Smith Bridge, much of the bank is private. Do not continue downstream without confirmed legal access.
The natural-area page and Au Sable Natural River plan are the access starting points for this report.
Do not treat navigable water as automatic permission to cross, park, or walk private banks.
Check Michigan DNR fire alerts and local forest-road conditions before remote summer access.
River sources
Official Au Sable River South Branch 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 restored report is maintained from official flow, regulation, access, weather, and public-land sources. Planning guidance is separated from live observations and legal rules.
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 8 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 this notice to check its current status, dates, and affected river section.
A statewide alert page is a check source, not proof that the South Branch or Mason Tract is closed.
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.
What this source covers
Open the land or access page, then check signs before you park or enter.
Quick answers
Quick Au Sable River South Branch answers.
What water does this South Branch Au Sable report cover?
The South Branch through the Mason Tract from Chase Bridge toward Smith Bridge and the main river, with access differences below Smith Bridge made explicit.
What should I check first before fishing South Branch Au Sable?
Check USGS 04135700 discharge and temperature, the 2026 Michigan rule section, trout maps, NWS alerts, and fire notices.
Is access straightforward on South Branch Au Sable?
The Mason Tract has a strong public area, but the banks below Smith Bridge are largely private and require separate confirmation.
Does the fishability score replace local judgment?
No. Use it as a starting decision, then confirm the source timestamp, official rules, alerts, water temperature, visibility, and conditions at the access you actually plan to use.