USGS Streamgage 11109600
Piru Creek above Lake Piru, CA
Piru Creek above Lake Piru, CA is USGS streamgage 11109600 in California, monitoring river discharge in hydrologic subbasin 18070102. It sits on the Piru Creek, alongside 1 other gauge Rivermatics tracks on the same river. It drains a watershed of about 372 square miles. Discharge records at this site go back to 1938. Typical flow runs near 12.2 cfs in July and 42.2 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.
View live conditions & forecast →
Gauge details
- State
- California
- Drainage area
- 372 sq mi
- Gauge elevation
- 1,062 ft
- Subbasin (HUC-8)
- 18070102
- Coordinates
- 34.52305, -118.75702
- USGS site number
- 11109600
- Records begin
- 1938-03-02 (88 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Piru Creek above Lake Piru, 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 |
|---|---|---|---|---|
| 47.6 | 50.3 | 54 | ||
| 46.1 | 50.2 | 54.6 | ||
| 43.8 | 50 | 55 | ||
| 40.3 | 49.7 | 55.3 | ||
| 35.3 | 49.4 | 55.4 | ||
| 29.9 | 49.1 | 55.8 | ||
| 26.1 | 48.5 | 56.2 | ||
| 22.3 | 47.6 | 56.2 | ||
| 18.3 | 46.7 | 57 | ||
| 20.6 | 48.2 | 64.9 | ||
| 12.2 | 45.5 | 57.9 | ||
| 10.2 | 43.7 | 57.3 | ||
| 9 | 42.2 | 56.9 | ||
| 9.3 | 41.7 | 56.8 |
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 55 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 | 6.6 | 27.2 | 193.7 | |
| February | 9.3 | 47.9 | 455.3 | |
| March | 10.4 | 64.4 | 444.9 | |
| April | 7.4 | 42.2 | 218.6 | |
| May | 3.7 | 27.8 | 110.2 | |
| June | 0.5 | 17.3 | 62.4 | |
| July | 0 | 12.2 | 41.3 | |
| August | 0 | 10 | 31.9 | |
| September | 0 | 8.6 | 27.3 | |
| October | 0 | 6.7 | 27.4 | |
| November | 2.3 | 9.9 | 71.2 | |
| December | 4.5 | 13.3 | 94.7 |
All values in cubic feet per second (cfs).
Common questions
- When does Piru Creek above Lake Piru, CA normally run highest?
- March, on the long-term record. The median daily flow that month is about 64.4 cfs, against 6.7 cfs in October, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Piru Creek above Lake Piru, CA?
- It depends on the month. In January, half of days historically fall near 27.2 cfs, with the middle 80% of days between 6.6 and 193.7 cfs. The month-by-month table on this page gives the full range.
- How long has Piru Creek above Lake Piru, CA been measured?
- Discharge records at USGS site 11109600 begin in 1938, about 88 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 Piru Creek above Lake Piru, 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. 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 Piru Creek above Lake Piru, CA?
- The gauge sits at 34.52305, -118.75702, in California, in hydrologic subbasin 18070102, at an elevation of about 1,062 feet, draining roughly 372 square miles.
- Can I use Piru Creek above Lake Piru, 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 Piru Creek
Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Piru Creek in full.
- Piru Creek above Lake Piru, CA this page
- Piru Creek below Santa Felicia Dam, CA 425 sq mi