USGS Streamgage 09429100
Colorado River below Palo Verde Dam, Az-Ca
Colorado River below Palo Verde Dam, Az-Ca is USGS streamgage 09429100 in California, monitoring river discharge in hydrologic subbasin 15030104. It drains a watershed of about 182,200 square miles. Discharge records at this site go back to 1956. Typical flow runs near 9,819 cfs in July and 10,375.7 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Drainage area
- 182,200 sq mi
- Gauge elevation
- 262 ft
- Subbasin (HUC-8)
- 15030104
- Coordinates
- 33.71914, -114.49754
- USGS site number
- 09429100
- Records begin
- 1956-03-24 (70 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 71 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 | 2,222.6 | 4,536.8 | 7,357.7 | |
| February | 3,844.1 | 6,499 | 8,410.3 | |
| March | 6,534.5 | 9,112.6 | 11,332.3 | |
| April | 8,013.7 | 10,375.7 | 12,430 | |
| May | 6,980.3 | 9,137.1 | 11,125.8 | |
| June | 7,180.3 | 9,532 | 11,403.3 | |
| July | 7,108.1 | 9,819 | 12,400 | |
| August | 5,785.8 | 8,395.2 | 11,601.3 | |
| September | 5,107.3 | 7,537.7 | 9,970 | |
| October | 4,528.4 | 6,434.2 | 8,221.6 | |
| November | 3,169.3 | 4,983.7 | 7,562 | |
| December | 2,012.4 | 3,988.1 | 6,465.8 |
All values in cubic feet per second (cfs).
Common questions
- When does Colorado River below Palo Verde Dam, Az-Ca normally run highest?
- April, on the long-term record. The median daily flow that month is about 10,375.7 cfs, against 3,988.1 cfs in December, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Colorado River below Palo Verde Dam, Az-Ca?
- It depends on the month. In January, half of days historically fall near 4,536.8 cfs, with the middle 80% of days between 2,222.6 and 7,357.7 cfs. The month-by-month table on this page gives the full range.
- How long has Colorado River below Palo Verde Dam, Az-Ca been measured?
- Discharge records at USGS site 09429100 begin in 1956, about 70 years, covering roughly 9,126 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is Colorado River below Palo Verde Dam, Az-Ca?
- The gauge sits at 33.71914, -114.49754, in California, in hydrologic subbasin 15030104, at an elevation of about 262 feet, draining roughly 182,200 square miles.
- Can I use Colorado River below Palo Verde 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.