Upper San Joaquin HUC8 18040006
A 4,244 km² sub-basin of the California region in CA. 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
80
Healthy
Drought index
100
Moderate
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
0%
of 1 reporting
Median flow
61%
p32 of record
Water assets
4,911
16 springs · 24 wells
USGS gauges (1)
- MF SAN JOAQUIN R NR MAMMOTH LAKES CA112240009 cfsp32 · normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 100 | 0 | 0/1 | p32 |
Top water assets
- 69Four Forks Creekriver
- 69South Fork San Joaquin Riverriver
- 69Purple Creekriver
- 69Potter Creekriver
- 69East Fork Chiquito Creekriver
- 69Piute Creekriver
- 69Senger Creekriver
- 69Daulton Creekriver
- 69South Fork San Joaquin Riverriver
- 69Boulder Creekriver