St. Vrain HUC8 10190005
A 2,539 km² sub-basin of the Missouri region in CO. 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
34
Stressed
Drought index
385
Extreme
Area in D2+
100%
0% exceptional (D4)
Gauges below normal
83%
of 6 reporting
Median flow
13%
p9 of record
Water assets
2,858
182 springs · 1,521 wells
USGS gauges (7)
- ST VRAIN CR BLW BOULDER CR AT HWY 119 NR LONGMONT0673052516 cfsp3 · much below normal
- BOULDER CREEK AT MOUTH NEAR LONGMONT, CO067305000 cfsp4 · much below normal
- BOULDER CREEK AT NORTH 75TH ST. NEAR BOULDER, CO0673020029 cfsp8 · much below normal
- FOURMILE CANYON CREEK NEAR SUNSHINE, CO067301600 cfsp10 · below normal
- FOURMILE CREEK AT ORODELL, CO067275000 cfsp11 · below normal
- LEFT HAND CREEK AT HOVER ROAD NEAR LONGMONT, CO067249703 cfsp31 · normal
- FOURMILE CREEK AT LOGAN MILL ROAD NEAR CRISMAN, CO067274100 cfsno long-term record
Recent conditions
| Date | DSCI | D2+ % | Gauges low | Flow pct |
|---|---|---|---|---|
| 2026-09-07 | 385 | 100 | 5/6 | p9 |
Top water assets
- 78Harrison Res — South Platte Riverwell
- 76Sandstone Ridge Ditch — South Platte Riverwell
- 76Mayer Well 1-14378 — Groundwater: South Platte Riverwell
- 76Nishimoto Well 1-15398 — Groundwater: South Platte Riverwell
- 76Yamaguchi Well 3-13988R — Groundwater: South Platte Riverwell
- 76Nishimoto Well 3-5503F — Groundwater: South Platte Riverwell
- 76Mayer Well 1-2881-F — Groundwater: South Platte Riverwell
- 73Nishimoto Well 4-12016 — Groundwater: South Platte Riverwell
- 73Nishimoto Well 3-12015 — Groundwater: South Platte Riverwell
- 73Mayer Well 2-13777 — Groundwater: South Platte Riverwell