Santa Margarita HUC8 18070302
A 1,919 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
61
Moderate
Drought index
56
Abnormally dry
Area in D2+
0%
0% exceptional (D4)
Gauges below normal
67%
of 12 reporting
Median flow
97%
p10 of record
Water assets
3,041
32 springs · 2,828 wells
USGS gauges (13)
- SANDIA C NR FALLBROOK CA110443500 cfsp0 · much below normal
- TEMECULA C NR AGUANGA CA110424000 cfsp10 · below normal
- WARM SPRINGS C NR MURRIETA CA110428000 cfsp10 · below normal
- SANTA GERTRUDIS C NR TEMECULA CA110429000 cfsp10 · below normal
- DE LUZ C NR DE LUZ CA110448000 cfsp10 · below normal
- FALLBROOK C NR FALLBROOK CA110453000 cfsp10 · below normal
- ONEILL LK SPILL CH NR FALLBROOK CA110457000 cfsp10 · below normal
- SANTA MARGARITA R A YSIDORA CA110460000 cfsp10 · below normal
- RAINBOW C NR FALLBROOK CA110442500 cfsp31 · normal
- SANTA MARGARITA R NR TEMECULA CA110440005 cfsp79 · above normal
- SANTA MARGARITA R A FPUD SUMP NR FALLBROOK CA1104430012 cfsp84 · above normal
- ONEILL LAKE OUTLET CH NR FALLBROOK CA1104560025 cfsp90 · much above normal
- MURRIETA C A TEMECULA CA11043000no readingno long-term record
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 56 | 0 | 8/12 | p10 |
Top water assets
- 67Cahuilla Creekriver
- 67Cahuilla Creekriver
- 67Temecula Creekriver
- 67Chihuahua Creekriver
- 67Cahuilla Creekriver
- 67Wilson Creekriver
- 67Temecula Creekriver
- 67Wilson Creekriver
- 67Arroyo Seco Creekriver
- 67Cahuilla Creekriver