Sources & thanks

Live data feeds

These are the agency feeds Riverbeta calls every time a page loads. All of them are free, public, and (as far as we can tell) taxpayer-funded — they exist because people decided river conditions should be a commons.

• USGS Water Services — real-time streamflow, water temperature, and gauge height for every gauge on the site, plus historical day-of-year percentiles that let us say where today's flow sits in the gauge's record.
• NOAA · National Weather Service — point forecast and active weather alerts, keyed to each gauge's coordinates.
• NOAA · National Water Prediction Service (NWPS) — short-range streamflow forecast (the 5-day forecast line on the flow chart).
• NOAA · Northwest River Forecast Center (NWRFC) — the 45-trace probabilistic Ensemble Streamflow Prediction that powers the season-range envelope and the trip-window outlook.
• NRCS · SNOTEL (Flattop Mountain) — basin snowpack as a percentage of median, the leading indicator for spring runoff in the Flathead drainage.
• National Park Service · Glacier — park alerts (closures, fire, road status including Going-to-the-Sun) keyed to put-ins and take-outs that sit inside or adjacent to the park.
• AirNow — current air-quality index (smoke matters here in late summer).

Verification & reference

The people and organizations whose written work we cite for run descriptions, rapid detail, regulations, and safety. The ones marked donate or subscribe only exist because members pay for them — if Riverbeta is useful to you, send some of that energy upstream.

• American Whitewater — the per-river, per-rapid pages and the volunteer-curated trip reports that everything from Cye Creek to The Ledge to Bonecrusher draws from. The standard reference for North American whitewater. Donate / become a member ↗
• Flathead Rivers Alliance — the source of the corridor regulations (PFD, IGBC bear-can, human waste, AIS, fire pan), the FRA river-mile values, and the current public alerts on the three forks. Local advocacy that works. Donate ↗
• Flathead Beacon — independent local journalism in the Flathead Valley; the primary source for the 2017 Ledge fatality we cite on the Big Creek → Glacier Rim safety note, and ongoing reporting on river accidents and access. Subscribe ↗
• Daily Inter Lake — Flathead Valley daily; secondary source on access, regulation, and incident reporting.
• National Park Service · Glacier — backcountry permitting (river-left of the North Fork & Middle Fork), Wild & Scenic management, official boundary data.
• US Forest Service · Flathead National Forest — corridor management on Forest Service land (river-right of the upper North Fork and most of the Middle Fork), access roads, dispersed camping rules.
• Rivers.gov · Wild & Scenic Rivers — official designation of the three forks as a Wild & Scenic system (one of the founding designations of the Act).
• Paddling Montana by Hank Fischer (Falcon Guides) — the standard guidebook for the state. Currently used as a calibration reference (e.g. Teakettle → Old Steel Bridge, which AW does not cover).

Outfitters & guides

Commercial whitewater outfitters whose published trip pages and run guides we drew on for class ratings, season windows, parking notes, and outfitter-side logistics. They're the ones with the deepest current ground truth on these reaches — book a trip with one of them if you want the guided version.

• Glacier Guides & Montana Raft Co. — West Glacier; whitewater + scenic + dinner floats; the long-range season window we use for West Glacier → Blankenship.
• Glacier Raft Co. — West Glacier; Middle Fork day and multi-day trips.
• Wild River Adventures — West Glacier area; day and overnight Middle Fork.
• Great Northern Whitewater Raft — West Glacier; day and multi-day.
• Wilderness River Outfitters — the specialized Schafer Meadows fly-in operator for the wilderness Middle Fork.

Maps & geometry

• Mapbox — the basemap on every interactive map (Flathead hero, basin, river, run), plus the Directions API used to compute shuttle distance and time.
• USGS · Network Linked Data Index (NLDI) — NHDPlus flowline geometry, used to draw the actual paddled line of every run on the maps.
• OpenStreetMap — the underlying open-data layer that Mapbox styles sit on top of. © OpenStreetMap contributors, ODbL.

Community beta

The community-beta notes on each run page are paddler posts and comments collected from public discussions in Flathead-area paddling groups, attributed to the paddlers who wrote them (first name only, no profile links). The originals belong to their authors — we curate, attribute, and link back where the source is public. If you wrote something quoted on this site and want it changed or removed, contact us.

Two long-standing paddler communities also stand out as the backbone of regional whitewater knowledge generally — even where we don't directly quote them, they shape the prior:

• Mountain Buzz — long-running paddling forum; rich historical Flathead threads.
• Backcountry Post — Northern Rockies trip-reports and regional discussion.

Software

Riverbeta is built with Next.js and React, hosted on Vercel, with Supabase (Postgres) as the database. Maps render with Mapbox GL JS. Sun and tide math via SunCalc. The poster-style design system is custom — derived from vintage USFS and US Park trail signage, drafted in Claude Design.

What we can't be

Riverbeta compiles, attributes, and surfaces. It does not replace local knowledge, current scouting, or your judgment on the water. Every claim on this site is somebody else's work plus a translation step — and translation steps can fail. The disclaimer & safety page spells out what that means before you rely on any of it.