Rillito HUC8 15050302
A 2,385 km² sub-basin of the Lower Colorado region in AZ. Drought coverage is from the US Drought Monitor (map of 2026-09-01); streamflow classes place each USGS gauge's latest reading against its own day-of-year record.
Health score
62
Moderate
Drought index
23
Abnormally dry
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
80%
of 10 reporting
Median flow
51%
p10 of record
Water assets
2,059
60 springs · 1,450 wells
USGS gauges (10)
- CIENEGA CREEK NEAR SONOITA, AZ.094845500 cfsp6 · much below normal
- TANQUE VERDE CREEK AT TUCSON, AZ.094845000 cfsp10 · below normal
- BARREL CANYON NEAR SONOITA, AZ094845800 cfsp10 · below normal
- RINCON CREEK NEAR TUCSON, AZ.094850000 cfsp10 · below normal
- PANTANO WASH AT BROADWAY BLVD. AT TUCSON, AZ.094854500 cfsp10 · below normal
- RILLITO CREEK AT DODGE BOULEVARD, AT TUCSON, AZ094857000 cfsp10 · below normal
- BRAWLEY WASH NEAR THREE POINTS, AZ.094870000 cfsp10 · below normal
- PANTANO WASH NEAR VAIL, AZ.094846000 cfsp14 · below normal
- SANTA CRUZ RIVER AT CORTARO, AZ0948650032 cfsp42 · normal
- SABINO CREEK NEAR TUCSON, AZ0948400063 cfsp96 · much above normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 23 | 0 | 8/10 | p10 |
Top water assets
- 70Lower Rose Canyonreservoir
- 67Agua Verde Creekriver
- 67Cienega Creekriver
- 67Cienega Creekriver
- 67Cienega Creekriver
- 67Rillito Riverriver
- 67Cienega Creekriver
- 67Tanque Verde Washriver
- 67Agua Verde Creekriver
- 67Sabino Creekriver