Middle San Joaquin-Lower Chowchilla HUC8 18040001
A 9,130 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
65
Moderate
Drought index
25
Abnormally dry
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
60%
of 5 reporting
Median flow
39%
p23 of record
Water assets
5,339
6 springs · 4,621 wells
USGS gauges (6)
- SALT SLOUGH A HWY 165 NR STEVINSON CA1126110028 cfsp9 · much below normal
- MUD SLOUGH NR GUSTINE CA112629005 cfsp19 · below normal
- SAN JOAQUIN R A FREMONT FORD BRIDGE CA1126150051 cfsp23 · below normal
- SAN JOAQUIN R AB MERCED R NR NEWMAN CA1127340072 cfsp31 · normal
- SAN JOAQUIN R BL FRIANT CA11251000379 cfsp70 · normal
- SAN JOAQUIN R NR MENDOTA CA11254000153 cfsno long-term record
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 25 | 0 | 3/5 | p23 |
Top water assets
- 67Oliver Creekriver
- 67De Long Creekriver
- 67West Fork Chowchilla Riverriver
- 67East Fork Chowchilla Riverriver
- 67Oliver Creekriver
- 67Little Panoche Detentionreservoir
- 67B.F. Sisk Damreservoir
- 67Los Banos Creek Detention Damreservoir
- 67Buchanan Damreservoir
- 67Mariposa Creekriver