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 2026-10-13); streamflow classes place each USGS gauge's latest reading against its own day-of-year record.
Health score
61
Moderate
Drought index
100
Moderate
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
100%
of 1 reporting
Median flow
49%
p11 of record
Water assets
4,911
16 springs · 24 wells
USGS gauges (1)
- MF SAN JOAQUIN R NR MAMMOTH LAKES CA112240005 cfsp11 · below normal
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-10-19 | 100 | 0 | 1/1 | p11 |
| 2026-10-18 | 100 | 0 | 1/1 | p11 |
| 2026-10-17 | 100 | 0 | 1/1 | p17 |
| 2026-10-16 | 100 | 0 | 1/1 | p20 |
| 2026-10-15 | 100 | 0 | 1/1 | p19 |
| 2026-10-14 | 100 | 0 | 0/1 | p28 |
| 2026-10-13 | 100 | 0 | 0/1 | p27 |
| 2026-10-12 | 100 | 0 | 0/1 | p28 |
| 2026-10-11 | 100 | 0 | 1/1 | p22 |
| 2026-10-10 | 100 | 0 | 1/1 | p22 |
| 2026-10-09 | 100 | 0 | 1/1 | p18 |
| 2026-10-08 | 100 | 0 | 1/1 | p19 |
| 2026-10-07 | 100 | 0 | 1/1 | p18 |
| 2026-10-06 | 100 | 0 | 1/1 | p17 |
Top water assets
- 69Senger Creekriver
- 69South Fork San Joaquin Riverriver
- 69South Fork San Joaquin Riverriver
- 69Piute Creekriver
- 69Four Forks Creekriver
- 69Daulton Creekriver
- 69Purple Creekriver
- 69Potter Creekriver
- 69East Fork Chiquito Creekriver
- 69Boulder Creekriver