Grayling, MI • Brown Trout • Rainbow Trout • Brook Trout
Au Sable Holy Waters
Loading live conditions…
—
CFS live
Water temp—
Flow (CFS)—
Barometric—
Air temp—
Cloud cover—
Wind—
Normal CFS—
Current Conditions
Flows are around 1,220 cfs and rising, above normal for mid October (Nearest active mainstem gauge — at Mio, downstream of the Holy Water). Water was 55°F at the gauge. Gates Au Sable Lodge reported Blue-Winged Olives and eggs on Oct 15. Streamers and nymphing for brown trout and brook trout in recent reports.
Evening rises on sulphur and PMD hatches have been exceptional. Hex season approaches — watch water temperatures closely. Nymphing the braids near Stephan Bridge has been reliable through the day. Fish run 12–18 inches with occasional 20+ inch browns.
Nearest active mainstem gauge — at Mio, downstream of the Holy Water
Hatch Calendar
SpeciesJanFebMarAprMayJunJulAugSepOctNovDec
HendricksonEphemerella subvaria
Sulphur / PMDEphemerella dorothea
Brown DrakeEphemera simulans
HexHexagenia limbata
TricoTricorythodes spp.
Mahogany DunParaleptophlebia spp.
Gear Recommendations
The Holy Water is one of America's premier dry fly rivers. Technical, clear water demands precise presentation and fine tippets.
Gear
Dry FlyRecommended
Nymphing
Euro Nymph
Streamer
Rod
9ft 4-weight or 5-weight
9ft 5-weight
10.5–11ft 2-weight or 3-weight
9ft 6-weight or 7-weight
Line
Double-taper floating (DT4F or DT5F) — less splash on presentation than weight-forward
Weight-forward floating with a strike indicator setup
Level 20lb Maxima or dedicated euro nymph line
WF floating or intermediate sink tip
Leader
12–15ft tapered leader
9ft tapered to 4X, add 18–24in tippet
Long mono rig (20ft+) with sighter section
6–9ft tapered to 1X–2X
Tippet
5X–7X fluorocarbon
5X–6X fluorocarbon
6X–7X fluorocarbon
1X–2X fluorocarbon or 15–20lb mono
Waders
Chest waders or hip waders in summer
Chest waders
Chest waders
Chest waders
Boots
Felt-soled wading boots (rubber with studs acceptable)
Felt-soled wading boots
Felt-soled wading boots
Felt-soled wading boots
Dry Fly Tips
The Au Sable's flat pools and educated trout demand the finest tippets. Drop to 7X in low clear conditions. The Hex hatch demands a size 4–6 fly so step up to 3X–4X leader for those nights.
Dry fly floatant (Loon Aquel or Frogs Fanny)Amadou patch for drying fliesLong-handled netPolarized sunglasses — essential for spotting risers
Nymphing Tips
High-stick nymphing in the braided sections between Stephan and Wakeley bridges. Small bead-head nymphs in size 14–18 match the Au Sable's invertebrate profile.
Thingamabobber indicators (small)Split shot assortment (BB and 3/0)Forceps and nippers
Euro Nymph Tips
Czech and French nymphing techniques work well in the Au Sable's riffles and pocket water. The long rod keeps line off the water in the technical dry fly sections.
Putty weight (Loon Biostrike)Small bead-head nymphs size 14–20Colored sighter material
Streamer Tips
Night streamer fishing during the Hex hatch produces the largest browns of the season. Mouse patterns on a floating line after midnight are a Holy Water tradition.
Large articulated streamers (sizes 2–6)Headlamp for night streamer sessions during HexWaterproof fly box
Find Your Guide
Gates Au Sable Lodge Guide Service
Orvis Endorsed
📍 Grayling, MIFloat (drift boat) and wade
Gates Lodge has guided the Holy Waters for decades. Their team of working guides includes experts on every section of the Au Sable system.
Specialties
Drift boat float tripsHoly Water wade tripsHex hatch nightsStreamer fishing
Pricing (2 anglers unless noted)
Full DayContact for pricing
GroupMulti-guide days available for groups
What's Included
All flies and tackle
Shore lunch on full days
Transportation from lodge
Expert local knowledge
What to Bring
Chest waders
Wading boots (felt or rubber with studs)
Rain gear
Polarized sunglasses
Michigan fishing license
Sunscreen and insect repellent
Camera
Book early — prime season dates (Hex hatch in June) fill months ahead
The Holy Water is a Gear Restricted reach — not a stream Type. Artificial flies only, and no trout may be kept at any time of year.
Burton's Landing → Wakeley Bridge — 9.0 miles (the Holy Water)
Fishing season open all year. Possession season closed all year — zero trout. Artificial flies only. Children under 12 may keep one trout, 8" minimum and 12" maximum. Wakeley Bridge down to McMasters Bridge is also Gear Restricted, under different limits.
Upstream and downstream of it
James St. up in Grayling down to Burton's Landing is Type 2. Below McMasters Bridge the mainstream becomes Type 4. Four sets of rules inside about thirty miles — the boundary is the water, not the bank you are standing on.
On a flies-only Gear Restricted reach it is unlawful to use or possess live, dead or preserved bait, organic or processed food, or scented material — on the water or on the bank. A bead is not a fly and is not allowed here.
The Au Sable River is Michigan's crown jewel of trout fishing, designated a Blue Ribbon trout stream. Fed by cold springs and groundwater seepage through glacial outwash plains, it maintains near-perfect temperatures year-round. The river was central to Michigan's logging era in the 1800s, used to float timber to sawmills downstream. After deforestation threatened the fishery, conservationists — including Aldo Leopold — helped shape the modern forest management practices that protect it today. The Au Sable remains one of the most studied and carefully managed rivers in America.
Did you know
Home to the famous "Holy Water" stretch from Grayling to Mio, considered among the finest dry fly water in North America.
Did you know
The Au Sable Canoe Marathon, held annually since 1947, covers 120 miles through the night from Grayling to Oscoda — the longest non-stop canoe race in the country.