Pick your float
Choose a river and your craft. We pull the latest gauge reading and estimate your time on the water.
Float times are estimates based on current gauge flow and typical drift speeds. Mileages are approximate. Conditions change fast — always scout, wear a PFD, and check MT FWP for closures.
River reports
Strainers, fences, diversion dams — if you saw it, report it. Help the next boat down.
Latest reports
Reports retire automatically after 45 days unless someone taps “Still there” — so what you see here is current, not last spring's news.
How the math works
Live gauge data
Every river here is tied to a USGS streamgage. We pull the instantaneous discharge (cfs) and water temperature, refreshed every time you load the page.
Flow → speed
River speed rises with discharge. We calibrate each river's typical drift speed at a reference flow, then scale it using the hydraulic-geometry relationship v ∝ Q0.34.
Your craft matters
A paddled kayak outruns the current; a tube with a cooler lags behind it. We adjust the estimate for what you're actually floating in.
Beat the sunset
We compute sunset at the put-in and tell you the latest reasonable launch time, so you're not navigating strainers in the dark.
More states are coming
Montana first — then the rest of the West. Idaho, Wyoming, and Colorado are next, with the same live-flow float times, daylight planning, and obstruction reports.