USGS Streamgage 09486055
Rillito Creek at La Cholla Blvd near Tucson, AZ
Rillito Creek at La Cholla Blvd near Tucson, AZ is USGS streamgage 09486055 in Arizona, monitoring river discharge in hydrologic subbasin 15050301. It drains a watershed of about 922 square miles. Discharge records at this site go back to 1990. Typical flow runs near 0 cfs in July and 0 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- Arizona
- Drainage area
- 922 sq mi
- Gauge elevation
- 2,246 ft
- Subbasin (HUC-8)
- 15050301
- Coordinates
- 32.30276, -111.01138
- USGS site number
- 09486055
- Records begin
- 1990-07-07 (36 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 31 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 | 0 | 0 | 5.2 | |
| February | 0 | 0 | 20.1 | |
| March | 0 | 0 | 9.2 | |
| April | 0 | 0 | 3.1 | |
| May | 0 | 0 | 0 | |
| June | 0 | 0 | 1.3 | |
| July | 0 | 0 | 56 | |
| August | 0 | 0 | 40.6 | |
| September | 0 | 0 | 15.1 | |
| October | 0 | 0 | 0.5 | |
| November | 0 | 0 | 0.1 | |
| December | 0 | 0 | 2.1 |
All values in cubic feet per second (cfs).
Common questions
- When does Rillito Creek at La Cholla Blvd near Tucson, AZ normally run highest?
- January, on the long-term record. The median daily flow that month is about 0 cfs, against 0 cfs in January, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Rillito Creek at La Cholla Blvd near Tucson, AZ?
- It depends on the month. In January, half of days historically fall near 0 cfs, with the middle 80% of days between 0 and 5.2 cfs. The month-by-month table on this page gives the full range.
- How long has Rillito Creek at La Cholla Blvd near Tucson, AZ been measured?
- Discharge records at USGS site 09486055 begin in 1990, about 36 years, covering roughly 9,124 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is Rillito Creek at La Cholla Blvd near Tucson, AZ?
- The gauge sits at 32.30276, -111.01138, in Arizona, in hydrologic subbasin 15050301, at an elevation of about 2,246 feet, draining roughly 922 square miles.
- Can I use Rillito Creek at La Cholla Blvd near Tucson, AZ 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.