River Report

South Santiam River Flow

3 streamgauges 92% of normal Last updated 2026-08-05

As of 2026-08-05, the South Santiam River is flowing at a combined 1,740 cfs across 3 USGS streamgauges — 92% of normal for this time of year, versus a seasonal average of 1,883 cfs.

Aggregate flow
1,740cfs
% of normal
92%
Daily volume
3,451AF
Seasonal avg
1,883cfs

Total streamflow across the South Santiam River was last observed at 1,740 cfs, and is expected to yield approximately 3,451 acre-ft of water today; about 92% of normal. Average streamflow for this time of year is 1,883 cfs, with recent peaks last observed on 2019-04-12 when daily discharge volume was observed at 53,930 cfs.

Maximum discharge along the river is currently at the South Santiam River At Waterloo reporting a streamflow rate of 852 cfs. However, the streamgauge with the highest stage along the river is the South Santiam River Near Foster with a gauge stage of 10.1 ft. This river is monitored from 3 different streamgauging stations along the South Santiam River, the highest being situated at an altitude of 777 ft, the South Santiam River Below Cascadia.

Max discharge

South Santiam River At Waterloo

852cfs
Highest stage

South Santiam River Near Foster

10.1ft
Highest-elevation gauge

South Santiam River Below Cascadia

777ft
Aggregate trend

River streamflow levels

Daily aggregate streamflow across every monitored gauge along the South Santiam River. Use the range buttons to zoom in on a specific period.

Total streamflow

Sum of all monitored streamgauges · daily

Per-gauge breakdown

Every streamgauge along the South Santiam River

All 3 USGS gauges Snoflo tracks for this river, with current flow, stage, recent change, percent of normal, and the gauge's all-time min / max. Click any header to sort. Cells are heatmapped relative to the column min/max -- darker blue = higher.

Streamgauge Streamflow (cfs) Gauge stage (ft) 24h Δ (%) % Normal Min (cfs) Max (cfs) Elevation (ft)
South Santiam River Below Cascadia OR
USGS 14185000
55 2.08 -2.3 97% 25 13,900 777
South Santiam River Near Foster OR
USGS 14187200
833 10.10 4.5 97% 705 24,100 524
South Santiam River At Waterloo OR
USGS 14187500
852 2.87 6.0 98% 747 25,200 378
Annual peaks

Maximum streamflow discharge by year

The single highest aggregate discharge recorded each year. Spotting the multi-year trend reveals droughts vs. wet cycles long before the headline daily flow does.

Annual peak discharge

From the river's full record · one point per water year

Profile

Streamflow elevation profile

Each bubble is one gauge along the river, plotted by current streamflow (x-axis) vs elevation (y-axis), sized by gauge stage. Reading top-to-bottom traces the river from headwaters down to its mouth -- you can see flow accumulate as elevation drops.

Elevation vs streamflow

One point per monitored gauge · bubble size = gauge stage

About this river

South Santiam River

The South Santiam River is located in the state of Oregon, USA. It is 66 miles in length and is a tributary of the Santiam River. The river has a long history of supporting agricultural communities along its length, such as the Sweet Home area, which was known for its logging and milling industries. The river is also known for its hydroelectric power generation, with several dams and reservoirs along its course. The Green Peter and Foster dams are two of the largest reservoirs on the river, providing water for irrigation and recreation opportunities. Recreational activities such as fishing, camping, and hiking are popular along the South Santiam River, making it a popular destination for outdoor enthusiasts.

Track the South Santiam River in the Snoflo app

Set per-gauge push alerts (e.g. "alert me when flow at the Russian R Nr Healdsburg crosses 5,000 cfs"), and Snoflo's iOS app pushes the moment USGS reports the crossing.

FAQ

About the South Santiam River

How is the South Santiam River flowing right now?

As of 2026-08-05, the South Santiam River is flowing at a combined 1,740 cfs across its USGS streamgauges, about 92% of normal for this date. The live per-gauge breakdown and 24-hour trend are shown above.

Is the South Santiam River running high or low right now?

Check the percent-of-normal figure on this page: above 100% means the river is running higher than its seasonal average for the date, below 100% means lower. The per-gauge table shows which reaches are highest and lowest.

Where does the data for the South Santiam River come from?

Streamflow and gauge stage data are sourced from the U.S. Geological Survey (USGS) National Water Information System. The aggregate flow shown at the top of the page is computed by Snoflo as the sum of all monitored gauges along the river.

How is "percent of normal" calculated?

Today's aggregate streamflow is compared to the historical average aggregate streamflow on this calendar day across the river's full record. 100% means right on average; values above 100% indicate above-normal flow (wet year); values below indicate below-normal (dry year or drought).

Why are some gauges showing very different flows?

Gauges along a river measure flow at different points: headwater gauges read what's coming off the snowpack or mountain runoff; downstream gauges integrate everything upstream, including tributary inputs. Wide spreads usually mean a tributary is contributing significantly between gauges.

What's the elevation profile chart showing?

Each bubble is one gauge along the river, plotted by streamflow (x-axis) and elevation (y-axis), sized by gauge stage. Reading top-down traces the river from headwaters to mouth -- you can see flow build as elevation drops.

Can I get alerts when a specific gauge crosses a threshold?

Yes -- alerts are managed in the Snoflo iOS app on a per-gauge basis. Open any individual streamgauge from the table above and favorite it to set a discharge threshold.