USGS Streamgage 11289650
Tuolumne River below Lagrange Dam near Lagrange, CA
Tuolumne River below Lagrange Dam near Lagrange, CA is USGS streamgage 11289650 in California, monitoring river discharge in hydrologic subbasin 18040009. It drains a watershed of about 1,538 square miles. Discharge records at this site go back to 1970. Typical flow runs near 107 cfs in July and 550.9 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Drainage area
- 1,538 sq mi
- Gauge elevation
- 173 ft
- Subbasin (HUC-8)
- 18040009
- Coordinates
- 37.6663, -120.4421
- USGS site number
- 11289650
- Records begin
- 1970-10-01 (56 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 56 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 | 126.3 | 329.6 | 4,195.2 | |
| February | 118.6 | 365.5 | 5,211 | |
| March | 138.2 | 362.4 | 6,256.5 | |
| April | 112.9 | 550.9 | 7,240 | |
| May | 12.9 | 429.5 | 6,988.1 | |
| June | 12.6 | 113.8 | 4,503.7 | |
| July | 12.5 | 107 | 1,550 | |
| August | 13.2 | 101.3 | 1,139.8 | |
| September | 10.9 | 106.2 | 1,280.1 | |
| October | 94.5 | 287.1 | 1,302.2 | |
| November | 156.2 | 256.2 | 705.3 | |
| December | 142.2 | 286.5 | 2,266.8 |
All values in cubic feet per second (cfs).
Common questions
- When does Tuolumne River below Lagrange Dam near Lagrange, CA normally run highest?
- April, on the long-term record. The median daily flow that month is about 550.9 cfs, against 101.3 cfs in August, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Tuolumne River below Lagrange Dam near Lagrange, CA?
- It depends on the month. In January, half of days historically fall near 329.6 cfs, with the middle 80% of days between 126.3 and 4,195.2 cfs. The month-by-month table on this page gives the full range.
- How long has Tuolumne River below Lagrange Dam near Lagrange, CA been measured?
- Discharge records at USGS site 11289650 begin in 1970, about 56 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 Tuolumne River below Lagrange Dam near Lagrange, CA?
- The gauge sits at 37.6663, -120.4421, in California, in hydrologic subbasin 18040009, at an elevation of about 173 feet, draining roughly 1,538 square miles.
- Can I use Tuolumne River below Lagrange Dam near Lagrange, 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.
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- Dry C A Crabtree Rd near La Grange, CA
- Tuolumne River A Modesto, CA
- Tuolumne River A Grand Cyn of Tuolumne Ab Hetch Hetchy
- Tuolumne River near Hetch Hetchy, CA
- Tuolumne River Ab Early Intake near Mather, CA
- Tuolumne River below Early Intake near Mather, CA
- Cherry C below Valley Dam near Hetch Hetchy, CA