USGS Streamgage 10150500
Spanish Fork at Castilla, UT
Spanish Fork at Castilla, UT is USGS streamgage 10150500 in Utah, monitoring river discharge in hydrologic subbasin 16020202. It drains a watershed of about 652 square miles. Discharge records at this site go back to 1890. Typical flow runs near 411.3 cfs in July and 201.2 cfs in April, with the higher of the two arriving in July. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.
View live conditions & forecast →
Gauge details
- State
- Utah
- Drainage area
- 652 sq mi
- Gauge elevation
- 4,870 ft
- Subbasin (HUC-8)
- 16020202
- Coordinates
- 40.04968, -111.54797
- USGS site number
- 10150500
- Records begin
- 1890-05-01 (136 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Spanish Fork at Castilla, UT. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.
| Date | Low p10 | Expected p50 | High p90 | Range |
|---|---|---|---|---|
| 226 | 253 | 269 | ||
| 197 | 245 | 279 | ||
| 152 | 217 | 263 | ||
| 135 | 202 | 253 | ||
| 120 | 190 | 244 | ||
| 117 | 185 | 238 | ||
| 110 | 180 | 235 | ||
| 113 | 181 | 235 | ||
| 114 | 181 | 234 | ||
| 118 | 183 | 237 | ||
| 110 | 178 | 233 | ||
| 102 | 171 | 228 | ||
| 97.7 | 169 | 227 | ||
| 69 | 155 | 235 |
All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 107 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.
| Month | Low p10 | Typical p50 | High p90 | Range |
|---|---|---|---|---|
| January | 51.4 | 79.3 | 136.2 | |
| February | 60 | 88.6 | 146.9 | |
| March | 74.2 | 116.6 | 231.4 | |
| April | 99.1 | 201.2 | 521.4 | |
| May | 212.4 | 424.1 | 966.7 | |
| June | 253.3 | 445.7 | 620.6 | |
| July | 271.2 | 411.3 | 538.2 | |
| August | 199.6 | 342.1 | 479.1 | |
| September | 115.4 | 204.9 | 314.2 | |
| October | 53.5 | 91.1 | 169.7 | |
| November | 54.2 | 79.9 | 142.6 | |
| December | 51.1 | 77.4 | 136.9 |
All values in cubic feet per second (cfs).
Common questions
- When does Spanish Fork at Castilla, UT normally run highest?
- June, on the long-term record. The median daily flow that month is about 445.7 cfs, against 77.4 cfs in December, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Spanish Fork at Castilla, UT?
- It depends on the month. In January, half of days historically fall near 79.3 cfs, with the middle 80% of days between 51.4 and 136.2 cfs. The month-by-month table on this page gives the full range.
- How long has Spanish Fork at Castilla, UT been measured?
- Discharge records at USGS site 10150500 begin in 1890, about 136 years, covering roughly 9,130 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Spanish Fork at Castilla, UT?
- Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
- Where is Spanish Fork at Castilla, UT?
- The gauge sits at 40.04968, -111.54797, in Utah, in hydrologic subbasin 16020202, at an elevation of about 4,870 feet, draining roughly 652 square miles.
- Can I use Spanish Fork at Castilla, UT data for flood or safety decisions?
- No. Rivermatics provides estimates, not guarantees, and the readings and forecasts here may be delayed, inaccurate, or wrong. Do not use them for navigation or for any safety, rescue, or emergency decision. Check the National Weather Service and USGS directly, and use your own judgment.