Streamflow data for whitewater paddlers.

H2OFlows is a free, open source gauge dashboard built by paddlers. Monitor your favorite rivers, set flow alerts, and explore reach data — all in one place.

Everything you need to check the river

    Live Gauge Dashboard

    CFS readings, sparklines, trend indicators, and 48-hour flow history for every gauge on your watchlist. Multi-dashboard support keeps different runs organized.

    Flow Band Labels

    Community-defined flow ranges (Too Low / Minimum / Optimal / Pushy) overlaid on live CFS. See at a glance if your run is on.

    Reach Pages

    Put-in and take-out coordinates, rapid inventory, access notes, and current conditions — all tied to live gauge data.

    Flow Alerts

    Get notified when a gauge crosses a threshold you care about. SMS, push, and Discord alerts coming in Phase 3.

    KMZ Import

    Build a reach in Google My Maps and import it directly. The importer reads pin prefixes and folder names — no SQL required.

    Public API

    All reach and gauge data is freely accessible via API. Build your own tools on top of the H2OFlows data layer.

Ready to check the river?

H2OFlows is free and open source. Sign in with Google to save your watchlist and get personalized flow alerts.