FAQ

Fishing questions, answered.

What is CFS in fishing?

CFS — cubic feet per second — is the standard unit for measuring how much water flows past a point in a river each second. One CFS equals about 7.5 gallons per second, roughly a basketball’s worth of water. For anglers, CFS tells you whether a river is wadeable, blown out, or running low. Most trout rivers fish best within 30% of their seasonal median flow.

What's a good CFS to fish at?

It depends on the river. The general rule: fishable flow is within ±30% of the historical median for that date. Below the range and fish concentrate in deep pools; above it and visibility drops below the productive threshold. Baseline Maps shows the historical median next to today's reading on every river page.

How do I know if a river is too high to fish?

Check visibility, not just CFS. If you cannot see at least 8 inches into the water, the river is generally not fishable regardless of what the gauge reads. After heavy rain, wait for the descending limb of the hydrograph — fish move back into productive water on the drop.

How accurate is USGS river flow data?

USGS provisional data is published within 15 minutes of measurement and is accepted as the authoritative real-time source for US river flow. Baseline Maps pulls directly from the USGS Water Services API — no resampling, no smoothing.

Is Driftline still a separate app?

No. Driftline is now the fishing mode inside Baseline Maps. All the same river data, intelligence, and features are there — plus hunting (Ridgeline) and foraging in the same app.

Does Baseline Maps work for fishing outside the Pacific Northwest?

Yes. River flow coverage includes Michigan steelhead waters, New York Salmon River, California coastal rivers, Alaska Kenai/Kasilof, plus inland waters in Utah, Wisconsin, Pennsylvania, Nevada, Minnesota, Ohio, Idaho. NOAA buoys cover the entire US Pacific Coast.