Streamflow
Below normalColorado River at Lees Ferry streamflow
Daily mean discharge, Colorado (Compact Point) basin, Arizona
Data through Sep 2, 2026 · source last checked Sep 10, 2026 · page revised Sep 3, 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 2, 2026
- Update frequency
- Daily
Now 8,010 cfs, 16% below the 5-yr median.
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.
| Period | Current | Prior | Change |
|---|---|---|---|
| Week over week | 8,010 cfs | 8,010 cfs | 0.0% |
| Month over month | 8,010 cfs | 7,880 cfs | +1.6% |
| Year over year | 8,010 cfs | 9,490 cfs | -15.6% |
| vs 5-yr median | 8,010 cfs | 9,580 cfs | -16.4% |
| Reading | Discharge |
|---|---|
| Lowest on record for this week | 8,260 cfs |
| Median for this week | 9,580 cfs |
| Highest on record for this week | 13,900 cfs |
Previous weeks
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.
Week of Aug 19, 2026
Lees Ferry streamflow at 7,970 cfs stands 36% below the 5-year median and is essentially flat week-over-week. Year-over-year discharge has declined 36% as summer drawdown continues in the upper Colorado basin.
An earlier week
Discharge at Lees Ferry stood at 7,930 cfs, 37% below the 5-year median. The gauge was down 36% from 12,400 cfs a year ago. Flow has held flat week to week.
Week of Aug 13, 2026
Colorado River discharge at Lees Ferry stood at 7,770 cfs on August 9, running 38% below the 5-year median. Flow is down 35.8% from a year ago, when the gauge read 12,100 cfs. Month over month, flow fell 1.4%.
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.