USGS Streamgage 09429490
Colorado River above Imperial Dam, Az-Ca
Colorado River above Imperial Dam, Az-Ca is USGS streamgage 09429490 in California, monitoring river discharge in hydrologic subbasin 15030104. It sits on the Colorado River, alongside 30 other gauges Rivermatics tracks on the same river. It drains a watershed of about 188,500 square miles. Discharge records at this site go back to 1973. Typical flow runs near 9,979 cfs in July and 11,036.7 cfs in April, with the higher of the two arriving in April. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead, alongside daily high and low water-temperature forecasts.
View live conditions & forecast →
Gauge details
- State
- California
- Drainage area
- 188,500 sq mi
- Subbasin (HUC-8)
- 15030104
- Coordinates
- 32.88494, -114.46811
- USGS site number
- 09429490
- Records begin
- 1973-10-16 (53 years)
- Rivermatics forecast
- 14-day flow outlook + water temperature
14-day flow forecast
Based on observations through for Colorado River above Imperial Dam, Az-Ca. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.
| Date | Low p10 | Expected p50 | High p90 | Range |
|---|---|---|---|---|
| 4,711 | 5,950 | 7,135 | ||
| 5,343 | 6,710 | 7,773 | ||
| 5,214 | 6,683 | 7,928 | ||
| 4,552 | 6,263 | 7,945 | ||
| 3,959 | 5,813 | 7,620 | ||
| 3,612 | 5,130 | 6,947 | ||
| 3,637 | 5,245 | 7,212 | ||
| 4,208 | 6,240 | 8,390 | ||
| 4,600 | 6,608 | 8,694 | ||
| 4,395 | 6,408 | 8,511 | ||
| 4,173 | 6,158 | 8,259 | ||
| 3,783 | 5,745 | 7,969 | ||
| 3,569 | 5,450 | 7,788 | ||
| 3,598 | 5,664 | 8,259 |
All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 50 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 | 3,149.4 | 5,179.4 | 14,938.7 | |
| February | 4,503.8 | 6,956.6 | 16,006.9 | |
| March | 6,961.3 | 9,519 | 15,038.7 | |
| April | 8,851.7 | 11,036.7 | 14,540 | |
| May | 7,791.9 | 9,725.2 | 13,738.7 | |
| June | 7,875.7 | 9,583.7 | 15,153.3 | |
| July | 7,816.1 | 9,979 | 17,332.3 | |
| August | 6,554.2 | 8,679.7 | 16,032.3 | |
| September | 6,198.3 | 7,839.7 | 14,703.3 | |
| October | 5,526.5 | 7,086.5 | 13,209.7 | |
| November | 4,361.3 | 5,909 | 12,076.7 | |
| December | 3,461.9 | 5,074.5 | 14,735.5 |
All values in cubic feet per second (cfs).
Common questions
- When does Colorado River above Imperial Dam, Az-Ca normally run highest?
- April, on the long-term record. The median daily flow that month is about 11,036.7 cfs, against 5,074.5 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 above Imperial Dam, Az-Ca?
- It depends on the month. In January, half of days historically fall near 5,179.4 cfs, with the middle 80% of days between 3,149.4 and 14,938.7 cfs. The month-by-month table on this page gives the full range.
- How long has Colorado River above Imperial Dam, Az-Ca been measured?
- Discharge records at USGS site 09429490 begin in 1973, about 53 years, covering roughly 9,130 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Colorado River above Imperial Dam, Az-Ca?
- Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. A companion model forecasts each day's water-temperature high and low. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
- Where is Colorado River above Imperial Dam, Az-Ca?
- The gauge sits at 32.88494, -114.46811, in California, in hydrologic subbasin 15030104, draining roughly 188,500 square miles.
- Can I use Colorado River above 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.
Upstream and downstream on the Colorado River
Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Colorado River in full.
- Colorado River below Baker Gulch near Grand Lake, CO 64 sq mi
- Colorado River below Shadow Mountain Reservoir, CO 190 sq mi
- Colorado River below Lake Granby, CO 312 sq mi
- Colorado River near Granby, CO 323 sq mi
- Colorado River at Windy Gap, near Granby, CO 788 sq mi
- Colorado River near Kremmling, CO 2,379 sq mi
- Colorado River at Catamount Bridge, CO 2,930 sq mi
- Colorado River near Dotsero, CO 4,390 sq mi
- Colorado River above Glenwood Springs, CO 4,556 sq mi
- Colorado River above Roaring Fork River at Glenwood Springs, CO 4,560 sq mi
- Colorado River below Glenwood Springs, CO 6,014 sq mi
- Colorado River below South Canyon Creek near Glenwood Springs, CO 6,050 sq mi
- Colorado River near Cameo, CO 7,986 sq mi
- Colorado River near Colorado-Utah State Line 17,849 sq mi
- Colorado River near Cisco, UT 24,100 sq mi
- Colorado River at Potash, UT 25,406 sq mi
- Colorado River at Gypsum Canyon near Hite, UT 71,200 sq mi
- Colorado River Ab Dirty Devil River near Hite, UT 75,530 sq mi
- Colorado River at Lees Ferry, AZ 111,800 sq mi
- Colorado River above Little Colorado River near Desert View 114,272 sq mi
- Colorado River near Grand Canyon, AZ 141,600 sq mi
- Colorado River above National Canyon near Supai 147,931 sq mi
- Colorado River below Hoover Dam, Az-Nv 171,700 sq mi
- Colorado River below Palo Verde Dam, Az-Ca 182,200 sq mi
- Colorado River above Imperial Dam, Az-Ca this page
- Colorado River below Imperial Dam, Az-Ca 188,500 sq mi
- Colorado River below Laguna Dam, Az-Ca 188,600 sq mi
- Colorado River below Yuma Main Canal Ww at Yuma, AZ 246,500 sq mi
- Colorado River at Nib, above Morelos Dam, AZ 246,700 sq mi
- Colorado River below Cooper Wasteway near Yuma, AZ
- Colorado River. above Gunnison River. at Grand Junction, CO
Other gauges in this subbasin
- Crir Main Canal near Parker, AZ
- Gardner Lateral Spill near Parker, AZ
- Poston Wasteway near Poston, AZ
- Palo Verde Canal near Blythe, CA
- Palo Verde Drain near Parker, AZ
- Crir Lwr Main Drain below Tyson Ww, near Ehrenberg, AZ
- Colorado River below Palo Verde Dam, Az-Ca
- Pvid F-Canal Spill near Blythe, CA