Streamflow
Near normalBoise River at Glenwood Bridge streamflow
Daily mean discharge, Boise-Snake basin, Idaho
Data through Oct 15, 2026 · source last checked Oct 17, 2026 · page revised Oct 16, 2026
Cite
- Discharge
About this data
- Source
- US Geological Survey (USGS)
- Series
- Daily mean streamflow (discharge)
- Geography
- Boise River at Glenwood Bridge
- Unit
- cfs
- Calculation
- Daily mean
- Last observation
- Oct 15, 2026
- Update frequency
- Daily
Now 270 cfs, 8% above the 5-yr median.
Boise River at Glenwood Bridge ran 270 cfs, down 21.5% from a week earlier. Flow fell 57.5% on the month as baseflow declined into fall. The gauge read 8% above its 5-year median.
| Period | Current | Prior | Change |
|---|---|---|---|
| Week over week | 270 cfs | 344 cfs | -21.5% |
| Month over month | 270 cfs | 635 cfs | -57.5% |
| Year over year | 270 cfs | 265 cfs | +1.9% |
| vs 5-yr median | 270 cfs | 250 cfs | +8.0% |
| Reading | Discharge |
|---|---|
| Lowest on record for this week | 208 cfs |
| Median for this week | 250 cfs |
| Highest on record for this week | 370 cfs |
Previous weeks
An earlier week
Discharge at Glenwood Bridge fell to 277 cfs, down 23.9% from the prior week. Flow has declined 56.4% in the month. The reading runs 16% above the 5-year median.
Week of Oct 7, 2026
Discharge at Glenwood Bridge was 364 cfs on October 7, 38% above the 5-year median. Flow dropped 6.4% week-over-week. Month-over-month the river fell 46.1%.
Week of Sep 30, 2026
Streamflow on the Boise River at Glenwood Bridge fell to 389 cfs, down 28% on the week. The gauge sits 23% below the 5-yr median. Flow has declined 47% over the past month.
Week of Sep 23, 2026
Boise River at Glenwood Bridge ran 589 cfs, down 5.9% on the week. Over the month, flow declined 24.6%. The gauge read 18% above its 5-year median.
About Boise River at Glenwood Bridge
The Boise River at Glenwood Bridge ran 270 cfs on Oct 15, 2026: 270 cubic feet of water passing the gauge every second (what cfs means), or about 536 acre-feet a day. That is 8% above the 5-year median of 250 cfs for the date. A month earlier it ran 635 cfs on Sep 15, 2026, so the river has fallen 57% since then. Below Boise the river runs west across the Treasure Valley and joins the Snake near Parma, on the Idaho-Oregon line, upstream of Hells Canyon.
USGS gage 13206000 sits on the Boise River at Glenwood Bridge, on the western edge of Boise, below the three federal reservoirs that control the basin: Anderson Ranch, Arrowrock and Lucky Peak. Nearly all of the roughly 2,700 square miles above it drains the Boise Mountains, and nearly all of the runoff is captured before it reaches the city.
The result is a year set by operations, not by hydrology. Flow is held low through the winter to keep flood space in the reservoirs, raised sharply in spring when that space has to be recovered, held at a high irrigation-season level through the summer, and cut back in the fall when deliveries end. That fall cut is often the largest single change in the record and it is a schedule, not a drought. The readings that carry real information are the flood-control releases in spring, which are constrained by channel capacity through Boise itself.