USGS Streamgage 09429500
Colorado River below Imperial Dam, Az-Ca
Colorado River below Imperial Dam, Az-Ca is USGS streamgage 09429500 in California, monitoring river discharge in hydrologic subbasin 15030107. It drains a watershed of about 188,500 square miles. Discharge records at this site go back to 1960. Typical flow runs near 369.2 cfs in July and 502.2 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Drainage area
- 188,500 sq mi
- Gauge elevation
- 133 ft
- Subbasin (HUC-8)
- 15030107
- Coordinates
- 32.86758, -114.47211
- USGS site number
- 09429500
- Records begin
- 1960-12-07 (66 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 8 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.
| Month | Low p10 | Typical p50 | High p90 | Range |
|---|---|---|---|---|
| January | — | 402.8 | — | |
| February | — | 357.1 | — | |
| March | — | 443.7 | — | |
| April | — | 502.2 | — | |
| May | — | 376.3 | — | |
| June | — | 363.5 | — | |
| July | — | 369.2 | — | |
| August | — | 395.3 | — | |
| September | — | 358.1 | — | |
| October | — | 272.4 | — | |
| November | — | 318 | — | |
| December | — | 345.4 | — |
All values in cubic feet per second (cfs).
Common questions
- When does Colorado River below Imperial Dam, Az-Ca normally run highest?
- April, on the long-term record. The median daily flow that month is about 502.2 cfs, against 272.4 cfs in October, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- How long has Colorado River below Imperial Dam, Az-Ca been measured?
- Discharge records at USGS site 09429500 begin in 1960, about 66 years, covering roughly 2,803 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is Colorado River below Imperial Dam, Az-Ca?
- The gauge sits at 32.86758, -114.47211, in California, in hydrologic subbasin 15030107, at an elevation of about 133 feet, draining roughly 188,500 square miles.
- Can I use Colorado River below Imperial Dam, Az-Ca data for flood or safety decisions?
- No. Rivermatics provides estimates, not guarantees, and the readings and forecasts here may be delayed, inaccurate, or wrong. Do not use them for navigation or for any safety, rescue, or emergency decision. Check the National Weather Service and USGS directly, and use your own judgment.
Other gauges in this subbasin
- Colorado River below Laguna Dam, Az-Ca
- Colorado Rvr above Ocean to Ocean Bridge near Yuma, AZ
- Colorado River below Yuma Main Canal Ww at Yuma, AZ
- Gila Gravity Main Canal at Imperial Dam, Az-Ca
- North Gila Main Canal near Yuma, AZ
- North Gila Main Canal No. 2 near Yuma, AZ
- All-American Canal near Imperial Dam, Ca-Az
- Reservation Main Canal near Yuma, AZ