Streamflow
Below normalColorado River at Lees Ferry streamflow
Daily mean discharge, Colorado (Compact Point) basin, Arizona
Data through Sep 30, 2026 · source last checked Oct 1, 2026 · page revised Oct 1, 2026
Cite
- Discharge
About this data
- Source
- US Geological Survey (USGS)
- Series
- Daily mean streamflow (discharge)
- Geography
- Colorado River at Lees Ferry
- Unit
- cfs
- Calculation
- Daily mean
- Last observation
- Sep 30, 2026
- Update frequency
- Daily
Now 7,940 cfs, 16% below the 5-yr median.
Discharge at Lees Ferry stood at 7,940 cfs, 16% below the 5-year median. Week over week the flow dipped 1.6%, while year-over-year it declined 15.6%.
| Period | Current | Prior | Change |
|---|---|---|---|
| Week over week | 7,940 cfs | 8,070 cfs | -1.6% |
| Month over month | 7,940 cfs | 7,880 cfs | +0.8% |
| Year over year | 7,940 cfs | 9,410 cfs | -15.6% |
| vs 5-yr median | 7,940 cfs | 9,410 cfs | -15.6% |
| Reading | Discharge |
|---|---|
| Lowest on record for this week | 6,570 cfs |
| Median for this week | 9,410 cfs |
| Highest on record for this week | 10,700 cfs |
Previous weeks
Week of Sep 23, 2026
Colorado River discharge at Lees Ferry is 8,070 cfs, 15% below the 5-yr median. Flow rose 3.1% on the week but sits 17.1% below last year's level.
Week of Sep 15, 2026
Discharge at Lees Ferry is 8,100 cfs, 16% below the 5-yr median. The river sits 18.5% below the prior year, though flow has risen 3.3% on the week.
Week of Sep 2, 2026
Lees Ferry streamflow is 8,010 cfs, 16% below the 5-year median. Year-over-year, flow has declined 15.6% from 9,490 cfs.
Week of Aug 26, 2026
Discharge at Lees Ferry reached 7,910 cfs, down 36.7% compared to a year ago. The flow runs 37% below the 5-year median.
About Colorado River at Lees Ferry
USGS gage 09380000 sits on the Colorado River at Lees Ferry, Arizona, about 15 miles below Glen Canyon Dam and just above the head of Grand Canyon. It is the most consequential streamflow station in the West: the Colorado River Compact divides the basin at this point, and the Upper Basin's delivery obligation to the Lower Basin is measured as flow past this gage.
Because it sits below Glen Canyon Dam, what it records is almost entirely a release schedule rather than a hydrograph. Reclamation sets an annual release volume for Lake Powell and shapes it month to month, so the natural snowmelt peak that dominates every unregulated gage upstream barely appears here; the visible pattern is instead the daily and seasonal rhythm of hydropower generation. A change in the level of this line is a change in policy, usually an annual operating decision made months earlier, and it shows up downstream in Lake Mead.