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How We Compile Our Data
A plain-language breakdown of what's live, what's real hand-research, and what's a general seasonal fallback — so you know how much to trust each part of a river card.
Live flow & gage height
Pulled straight from the USGS National Water Information System — the same public gauge network agencies, guides, and river forecasters use. Readings are fetched live the moment you open a river card and refresh automatically about every 5 minutes. USGS blocks direct requests from browsers, so those live calls are routed through a small proxy service we run rather than being faked or cached for long periods.
"Typical for this month" flow range
This is different from the live reading above — it's historical context for whether today's flow is unusually low, normal, or high for the season. For each gauge we pull USGS's full period-of-record daily statistics and derive four numbers: low is the lowest 10th-percentile flow seen in any month, the optimal range is the median of each month's 25th- and 75th-percentile flows across the year, and high is the highest 90th-percentile flow seen in any month. Every river card links directly to the USGS source data behind its numbers.
Weather & moon phase
Weather comes live from Open-Meteo for each river's coordinates. Moon phase is computed locally with an astronomical calculation rather than fetched from a third party, so it's always available even when a live data source is down.
Species, seasons & regulations
Species and season summaries are hand-parsed from Washington's official special fishing rules (via eregulations.com's special-rules pages, sourced from WDFW's published regulations) for the roughly 442 named waters that have a documented special rule — covering open/closed water status, species present, and harvest type. This is a planning summary, not the current rule: seasons, size limits, and open sections change from year to year and sometimes mid-season, so every regs section links to the official current WA Sport Fishing Rules pamphlet to confirm before you fish.
"What to try this month" flies
For the rivers we've researched in depth — 9 built out in full detail plus 57 more with real monthly fly and hatch data — these come from actual sources: fly shop reports, guide sites, and published hatch charts, cited wherever the app shows them. For every other named Washington water, we fall back to a type- and region-aware seasonal profile (adjusted for things like closed water, whitefish-only seasons, and warmwater vs. coldwater species) instead of one generic guess for the whole state. It's a reasonable seasonal starting point, not a report on that specific piece of water.
The honest version
Nobody on our end is standing on the bank checking conditions each morning. This app compiles public data feeds and hand-researched fishery information into one place — it's a planning tool, not a substitute for confirming current regulations or calling a local fly shop for what's actually happening on the water right now.
Reel North Reports