BirdTrout

Au Sable River, Michigan

138 mapped river miles, draining 1,864 square miles across Alcona, Crawford, Iosco, Oscoda counties, in the Au Sable River watershed. 8 USGS gauges report water temperature on it, and this page reads all 8.

Open in BirdTrout →

Public land — where the bank is open to walk and fish

USGS gauge — live water temperature

Water temperature — the colour of the river, and of every dot on it

58 64 70

50°F and colder is cold, through cold-transitional and cool, to warm above 70°F — the same four bands, breaking at 58, 64 and 70°F, that the app paints. Grey is water nobody has measured.

Water temperature right now

Live from the USGS — every pill above is live, so the numbers you are reading are the latest continuous readings at each gauge. Provisional and unreviewed, as all real-time data is. If that fetch cannot happen — you are offline, or the USGS is down — the pills fall back to the last value we cached, 30 September 2026, 13:43 UTC. Not all of them, though: Red Oak is not reporting water temperature — it reported on only 16 of the last 30 days. That pill carries a modelled temperature where one can be fitted, marked as modelled, and a dash where it cannot — never a stale reading dressed as a current one.

The pills above go to USGS. These are this site's pages for the same gauges — a thirty-day chart, the monthly means, the record, and today's reading against the five-year normal for today: 04136000, 04136500, 04136900, 04137005.

The character of the water

Thermal classification

Each gauge carries a July mean built from its own daily record — 8 Julys, 2019–2026, measured rather than modelled. A July mean is what decides which of the four bands a stretch of water belongs to, because July is when a trout river either holds or does not.

Every gauge sits at the bottom of its segment, so each number is the warm end and the water above it runs colder. ±2.2 °F on the fit.

Named stretches

Anglers name parts of this river. These are the names two or more independent sources use; each page says which sources, because a nickname is the one thing on this site that is not a measurement.

• Holy Water — The nine miles of Au Sable mainstem between Burton's Landing and Wakeley Bridge, east of Grayling. Flies-only and no-kill since long before either rule was common, and the stretch most often meant when somebody says they are fishing the Au Sable.
• Trophy Water — The Au Sable below Mio Pond dam down to McKinley Bridge, managed for size rather than numbers. Big, open, cold tailwater — floated far more often than it is waded.

The lake run

The Au Sable River is a Lake Huron tributary with 10.2 miles of run corridor on it — salmon, steelhead and lake-run brown trout, on their own calendar and under their own rules. Run timing, species and access on the Au Sable River →

Questions about this river

• Au Sable River fishing report — what it reads right now
• When to fish the Au Sable River — hatches, seasons and temperature
• How to get to the Au Sable River — access, parking and public land
• Au Sable River fishing regulations — season, size and gear by reach
• Is the Au Sable River good for brook trout?
• Is the Au Sable River good for brown trout?
• Is the Au Sable River good for rainbow trout?

Regulations

MDNR trout stream types, as designated. Types on file cover 67.5 of the 137.9 mapped miles; 70.4 miles carry no type in this dataset. Always check the current Michigan Fishing Guide before you fish — this is a copy, and the Guide is the rule.

Creel across all types: 5 fish, with no more than 3 trout 15“ or greater. Zero (0) Arctic Grayling. Tackle: Artificial lures and all types of natural bait may be used.
Type 3: Closed to fishing year round: Foote Dam to the downstream edge of the dam apron.

Blue Ribbon. Main Branch AuSable River (BR 15), 63.7 mapped miles. MDNR's limits, verbatim — upstream: Upper Section: Co. 612, Lower Section: Mio Dam; downstream: Upper Section: Luzerne Co. Pk., Lower Section: Alcona Line.

Fishable reaches

River miles are measured above the mouth, along the mapped mainstem. The reach breaks are the gauges, which is also how the temperature model divides the river.

46 mapped access sites on the mainstem: 30 walk-in, 16 boat or canoe launches. Source: MDNR.

USGS gauges

Every gauge on the mainstem, upstream first. Links go to the USGS monitoring-location page for the site.

• Au Sable River near Red Oak — 04136000 · RM 89.1
  225 July days of record across 8 Julys (2019–2026) · 739 cfs at last read
• Au Sable River at Mio — 04136500 · RM 71.8
  248 July days of record across 8 Julys (2019–2026) · 879 cfs at last read
• Au Sable River near Mc Kinley — 04136900 · RM 60.0
  242 July days of record across 8 Julys (2019–2026) · 1,010 cfs at last read
• Au Sable River near Curtisville — 04137005 · RM 50.2
  248 July days of record across 8 Julys (2019–2026) · 1,150 cfs at last read
• Au Sable River near South Branch — 04137020 · RM 41.2
  215 July days of record across 7 Julys (2019–2026)
• Au Sable River near Glennie — 04137025 · RM 35.8
  239 July days of record across 8 Julys (2019–2026)
• Au Sable River near Sidtown — 04137030 · RM 26.5
  247 July days of record across 8 Julys (2019–2026)
• Au Sable River near Au Sable — 04137500 · RM 11.0
  246 July days of record across 8 Julys (2019–2026) · 1,130 cfs at last read

Public land on the river

21 units of public or open-access land touch this river, 342,391 acres in total. Acreage is the whole unit, not the part beside the water.

Species

MDNR's most recent survey on this river ran in 2022 at Au Sable River, Crawford County, in a channel averaging 89 feet: brook trout, brown trout, rainbow trout, at 2,157 trout per acre and 115 pounds per acre. MDNR strata: medium, land-locked, wild trout; regulation at the station, gear restricted.The station has been surveyed in 45 years since 1960.

• Brook trout surveyed
• Brown trout surveyed
• Rainbow trout surveyed
• Atlantic salmon stocked only
• Chinook salmon stocked only
• Coho salmon stocked only
• Lake trout stocked only
• Yellow Perch stocked only

Stocked, per the MDNR record: Atlantic salmon, Brook trout, Brown trout, Chinook salmon, Coho salmon, Lake trout, Rainbow trout, Yellow Perch. The most recent plants are Atlantic salmon, Coho salmon, Rainbow trout at Rea Road (Iosco Co., through 2026); Atlantic salmon, Coho salmon at Whirlpool PAS (Iosco Co., through 2026); Brown trout, Rainbow trout at Bamfield Road Bridge (Alcona Co., through 2026).

Historical July mean

The measured record behind every temperature band on this page: the mean of the daily means for July, at each gauge, over the years USGS has one.

Hatches on this water

53 insects are recorded from northern lower Michigan, which is the region this river sits in. That is a claim about the region and not a survey of this stream: nobody has recorded which of them has been caught here. Open the river in the app and the hatch panel will narrow it to the ones whose temperature window today's reading is inside.

And 39 more — the year-round records, mostly: midges, scuds and sculpins, which are in the water every day and are therefore never the news.

Tributaries and watershed

35 named streams meet this one. Confluence miles are above the mouth; the longest twelve are listed.

• South Branch Au Sable River 51.5 mi · RM 104.5
• North Branch Au Sable River 37.0 mi · RM 97.8
• Van Etten Creek 20.8 mi · RM 2.3
• Beaver Creek 20.3 mi · RM 91.7
• East Branch Au Sable River 17.7 mi · RM 121.7
• South Branch River 13.0 mi · RM 39.6
• Kolke Creek 10.7 mi · RM 137.9
• Lost Creek 9.7 mi · RM 85.1
• Blockhouse Creek 9.3 mi · RM 56.7
• Wilbur Creek 8.9 mi · RM 51.3
• Cherry Creek 8.5 mi · RM 76.5
• Perry Creek 8.3 mi · RM 72.7

Au Sable River sits in HUC 8 04070007, the Au Sable River watershed, and drains 1,864 square miles, Strahler order 6 at the mouth. 169 NHD reaches carry the name for 137.7 miles in total.

Other water nearby

The closest 6 rivers on this site, straight-line from the middle of this one — not drive time.

• Cauchy Creek 3.5 mi
• Wolf Creek 4.5 mi
• Glennie Creek 5.4 mi
• Houghton Creek 5.8 mi
• Comins Creek 6.1 mi
• Antler Creek 6.7 mi