Montana Tailwater
Missouri River Fishing Report, Flows and Hatches
A broad tailwater below Holter Dam that fishes more like an oversized spring creek. Heavy hatches, technical dry fly water, and trout counted in the thousands per mile.
Tailwater
Montana
3,460 ft
Gauge 06066500
Right now
Live conditions
Flow
3,230 cfs
Water temp
62°F
Air (Tonight)
61°F
Sky / wind
Showers and thunderstorms likely, wind 2 to 14 mph
Last updated July 14 at 7:45 PM MDT
The hatch chart
Missouri River hatches by month
The emergences that come off the Missouri by month, straight from the Rivus hatch model.
| Hatch | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Midge Midge, #18-24 | ||||||||||||
Small Baetis Mayfly, #20-24 | ||||||||||||
Blue Winged Olive Mayfly, #14-22 | ||||||||||||
Grannom / Mother's Day Caddis Caddis, #14-16 | ||||||||||||
Caddisfly Caddis, #14-18 | ||||||||||||
Pale Morning Dun Mayfly, #16-18 | ||||||||||||
Trico Mayfly, #20-24 | ||||||||||||
Pale Evening Dun Mayfly, #14-16 | ||||||||||||
October Caddis Caddis, #10-12 |
How it fishes
A Montana tailwater
A tailwater runs out of the bottom of a dam, so the water comes out cold and steady all year. That stable temperature is why the bugs stay small and the hatches run like clockwork, and it is why the fish grow picky and well fed. The flip side is that the dam sets the flow, not the weather, so a release can change the river overnight. You read the gauge, not the sky.
Flow and gauge
Reading the flows
The Missouri is metered at USGS gauge 06066500. Because a dam sets the flow, the number can change overnight with a release, so it is worth a look before you load the truck.
Low
under 4,000 cfs
Optimal
4,000 to 7,000 cfs
High
above 8,000 cfs
Access and regulations
Before you fish
Access and the right to fish are the angler’s responsibility, every time. Public access, private water, and seasonal closures vary along the river, so confirm where you can legally stand and wade before you go. We do not point you to a specific spot.
Read the current rules, license requirements, and any special-regulation water before you go. Regulations change season to season, so check them fresh.
Flow and water temperature from USGS, weather from NWS and NOAA, refreshed hourly. Real-time USGS readings are provisional and subject to revision. The hatch chart and river read are Rivus model output.