South Santiam River At Waterloo flow report
As of July 12, 2026, South Santiam River At Waterloo is flowing at 813 cfs with a gage height of 2.83 ft. Source: USGS gauge #14187500, refreshed throughout the day.
Historical Data
South Santiam River At Waterloo at a glance
How South Santiam River At Waterloo is running right now, where it sits on the map, and the key gauge stats.
South Santiam River At Waterloo is flowing at 813 cfs, with the water sitting 2.83 ft at the gage.
This is USGS gauge #14187500 in Oregon. Over the past 10 days the average has been 932 cfs, peaking at 1,050 cfs.
Over the next 5 days, South Santiam River At Waterloo is expected to hold near today's 813 cfs, toward roughly 776 cfs by 2026-07-17 (likely range 685-880 cfs) -- running well below the seasonal normal.
For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the Oregon flow report.
Streamflow Forecast
Powered by PULSE — Snoflo’s Predictive Unified Learning & Simulation Engine, which learns from how this river has answered every past storm, snowmelt, and dry spell to forecast where it’s headed with a precision generic models can’t match.
How does this compare to past years?
Year-over-year overlay, annual peak discharge, the full distribution of daily flows on record, and the gauge's rating curve.
Weather Forecast
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day forecast
Daily temperatures, snow, and rain projected over the next two weeks.
South Santiam River At Waterloo
The primary constituents of the river's flow come from precipitation and snowmelt in the surrounding mountains. There are several tributaries that feed into the South Santiam River, including the Quartzville Creek, Crabtree Creek, and Soda Creek. The US Army Corps of Engineers maintains several dams on the river, including the Foster Dam and the Green Peter Dam. Seasonal trends in flow include peak flows during the spring snowmelt and lower flows in the summer months. An interesting fact about the South Santiam River is that it is a popular location for fishing, with several species of trout and salmon present in the river.
Nearby streamflow levels
Cross-check South Santiam River At Waterloo's discharge against nearby gauges to spot whether the change here is local or regional.
| Gauge | Streamflow |
|---|---|
| South Santiam River At Waterloo | 813 cfs |
| Lebanon Santiam Canal Near Lebanon | 75 cfs |
| South Santiam River Near Foster | 869 cfs |
| Wiley Creek Near Foster | 17 cfs |
| Thomas Creek Near Scio | 26 cfs |
| North Santiam River Near Jefferson | 937 cfs |
Nearby snowpack data
Snowpack at SNOTEL stations near South Santiam River At Waterloo. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.
| SNOTEL station | Snowpack |
|---|---|
| Foster Dam | 0 in |
| Corvallis Municipal Airport | 0 in |
| Little Meadows | 0 in |
| Little Meadows | 0 in |
| Eugene-Mahlon Sweet Field | 0 in |
| Jump Off Joe | 0 in |
River levels & flood safety
- Read the level before you go
- A river that's runnable at one flow can be deadly at another. Check current discharge and gage height — like the values shown above — against the flood-stage thresholds, and remember levels can spike fast after rain or a dam release.
- Respect cold water
- Snowmelt rivers run cold even in summer. Sudden immersion triggers cold-water shock and saps strength within minutes. Wear a PFD, dress for the water temperature (not the air), and never wade or paddle alone.
- Watch for swiftwater hazards
- Strainers (downed trees), undercut rocks, and low-head dams are the deadliest features on moving water. High, fast, muddy water hides them. If in doubt, scout from shore and portage.
- Mind flash floods & releases
- Narrow canyons can flood from a storm miles upstream, and dam-controlled reaches can rise without warning. Know the forecast, the release schedule, and your exit before you launch.
Track South Santiam River At Waterloo in the Snoflo app
Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when South Santiam River At Waterloo crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.
About South Santiam River At Waterloo
Where does the streamflow data for South Santiam River At Waterloo come from?
Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 14187500. Snoflo refreshes the time series throughout the day. Forecasts come from the NOAA / yr.no feed Snoflo's iOS app uses.
How often is the report updated?
USGS gauges report continuously (typically every 15 minutes). Snoflo pulls fresh values throughout the day — look for the "as of" timestamp on the streamflow hero card.
What's the difference between discharge and gage height?
Discharge (cubic feet per second, or cfs) is the volume of water flowing past the gauge each second. Gage height is how high the water sits at the gauge (feet). They're related by a rating curve specific to each gauge — higher water means more flow, but the exact ratio depends on channel shape.
How is "percent of median" calculated?
Today's discharge is compared to the historical median discharge on this calendar day across the gauge's full record. 100% = right on median; 200% = a very high year; 30% = a drought-level low.
What are flood stages, and is this river safe right now?
Flood stages are NWS-defined gage-height thresholds — Action, Minor, Moderate, Major — marking when nearby roads or floodplains start to be affected. "Safe" depends on your activity and skill: a level that's a fun paddle for an expert can be lethal for a wader. Always check the current level against the thresholds above and the safety links, and when in doubt, stay off the water.
Can I get alerts when South Santiam River At Waterloo rises?
Yes — flow alerts are managed in the Snoflo iOS app. Favorite this gauge, set a streamflow threshold (e.g. "alert me when discharge crosses 5,000 cfs"), and you'll get a push the moment USGS reports the crossing.
Access the free South Santiam River At Waterloo report
Create your free account to track this river — and everything else you love on the water.
- Flow alerts — get pinged the moment this river hits your range
- Save favorites — every river, lake & snowpack in one place
- Full history & forecasts — plus the free iPhone app