Every river, every gauge.
Live levels rolled up from USGS streamgauges across thousands of named U.S. rivers — discharge, percent-of-normal, and river length, refreshed throughout the day. Built for paddlers, anglers, water managers, and anyone who lives downstream.
What U.S. rivers are doing
How the country's rivers are running — discharge patterns, regional context, and where to go for the full picture.
The U.S. river network spans roughly 3.5 million miles of streams and rivers, from snowmelt-fed headwaters in the Rockies and Sierra to the warm-water systems of the Southeast and the braided arctic rivers of Alaska. The Mississippi-Missouri system alone drains 41% of the contiguous U.S.
Snoflo joins live USGS streamgauge readings to named river geometries, so every river with three or more reporting gauges gets a roll-up showing peak discharge, percent-of-normal, and length. Western rivers tend to peak in late spring as snowpack melts; eastern systems are more rain-driven and respond fastest to multi-day frontal storms.
Drill into any river below for its full streamgauge inventory and historical levels. For the daily AI summary of nationwide flow conditions, see the flow report.
Rivers ranked by current discharge
Named rivers with at least three reporting USGS gauges, sorted by peak streamflow right now. Tap any one for its full gauge inventory and historical levels.
| River | Length | Gauges | vs. Normal | Peak discharge |
|---|---|---|---|---|
| Mississippi River | 2,389 mi | 20 | ↓ 41% | 194,000 cfs |
| Columbia River | 687 mi | 4 | ↓ 68% | 178,000 cfs |
| Ohio River | 970 mi | 7 | ↑ 141% | 93,100 cfs |
| White River | 2,378 mi | 37 | ↑ 256% | 50,600 cfs |
| Savannah River | 458 mi | 6 | 128% | 45,200 cfs |
| Missouri River | 1,853 mi | 25 | ↓ 53% | 42,700 cfs |
| Kennebec River | 142 mi | 3 | ↑ 270% | 19,300 cfs |
| Piscataquis River | 63 mi | 3 | ↑ 531% | 18,600 cfs |
| Connecticut River | 389 mi | 10 | 125% | 18,400 cfs |
| Snake River | 1,452 mi | 27 | 82% | 12,600 cfs |
| Susquehanna River | 451 mi | 16 | ↓ 61% | 12,400 cfs |
| Apalachicola River | 101 mi | 3 | ↓ 65% | 12,100 cfs |
| Androscoggin River | 169 mi | 4 | ↑ 231% | 11,700 cfs |
The longest rivers Snoflo tracks
U.S. rivers with continuous gauge coverage, ranked by total length. Useful jumping-off points for paddlers planning multi-day trips and anglers chasing migrations.
| River | Length (mi) | Gauges |
|---|---|---|
| Mississippi River | 2,389 | 20 |
| White River | 2,378 | 37 |
| Colorado River | 2,202 | 35 |
| Black River | 1,988 | 23 |
| Missouri River | 1,853 | 25 |
| Little River | 1,847 | 36 |
| Green River | 1,553 | 20 |
| Arkansas River | 1,467 | 30 |
| Snake River | 1,452 | 27 |
| Canadian River | 1,141 | 10 |
| James River | 1,125 | 25 |
| Ohio River | 970 | 7 |
| Brazos River | 948 | 15 |
| Pecos River | 919 | 26 |
| Cumberland River | 859 | 4 |
| Salmon River | 789 | 8 |
| Yellowstone River | 772 | 9 |
| Cimarron River | 761 | 12 |
About the river data
Where does this data come from?
Discharge readings come directly from the U.S. Geological Survey (USGS) streamgauge network — 10,000+ stations spread across every state. Snoflo joins the live readings to named river geometries so every river with at least three reporting gauges gets a single roll-up entry.
What is "cfs"?
Cubic feet per second — the standard unit for streamflow. One cfs is roughly 7.5 gallons per second flowing past the gauge. Small creeks run at single-digit cfs; the Mississippi runs at hundreds of thousands.
What does "percent of normal" mean?
The current discharge compared to the historical average for the same date at that gauge. 100% is right at the historical norm. 130%+ flags an elevated river that's worth watching; 200%+ on a small-to-medium river is a strong indicator of flood conditions; below 70% indicates drought-stressed flow.
Why doesn't my favorite river show up?
Rivers need at least three reporting USGS gauges to make this list. Smaller creeks, headwater tributaries, and intermittent streams often have only one gauge or none. Try the flow report for individual gauges, or the interactive map to find what's nearby.
How fresh is the data?
USGS streamgauges report every 15 minutes; we re-pull every hour and re-rank. The river-level rollup regenerates throughout the day.
Can I get an alert when a river fires?
Yes. Save any USGS gauge as a favorite in the Snoflo iOS app, set a discharge threshold (e.g. "alert me at 5,000 cfs" or "alert me on stage above 12 ft"), and you'll get a push the moment it crosses. Free with a Snoflo account.