8 USGS Streamgages
Santa Cruz River flows and levels
Santa Cruz River is gauged at 8 USGS streamgages in Arizona, each tracked by Rivermatics. The mainstem runs about 187 miles (301 km) from headwaters to outlet. It drains roughly 4,872 square miles at its outlet. The gauged reach falls about 2,734 feet, from 4,633 feet down to 1,899. Rivermatics issues a daily machine-learned 14-day flow outlook for every one of them.
Gauges on this river, upstream to downstream
Ordered by drainage area, which is how far down the river each gauge sits. April and July figures are long-term median daily flows for that month from the USGS record — historical normals, not a forecast and not today's reading.
| Gauge | State | Drainage sq mi | Elevation ft | April p50 cfs | July p50 cfs | Forecast |
|---|---|---|---|---|---|---|
| Santa Cruz River near Lochiel, AZ | AZ | 82 | 4,633 | 0.3 | 0.2 | 14-day |
| Santa Cruz River near Nogales, AZ | AZ | 533 | 3,705 | 1.8 | 1.5 | 14-day |
| Santa Cruz River at Tubac, AZ | AZ | 1,210 | 3,166 | 10.5 | 8.8 | 14-day |
| Santa Cruz River at Continental, AZ | AZ | 1,682 | 2,807 | 0 | 0 | 14-day |
| Santa Cruz River at Tucson, AZ | AZ | 2,222 | 2,323 | 0 | 0.5 | 14-day |
| Santa Cruz River at Cortaro, AZ | AZ | 3,503 | 2,124 | 38.3 | 40.5 | 14-day |
| Santa Cruz River at Trico Road, near Marana, AZ | AZ | 3,641 | 1,899 | 15.6 | 13.4 | 14-day |
| Santa Cruz River at Silverlake Rd, at Tucson, AZ | AZ | — | 2,328 | 0 | 0 | 14-day |
Typical flow by month at Santa Cruz River at Silverlake Rd, at Tucson, AZ
The furthest-downstream gauge on this river, so the fullest flow it carries here. Long-term daily discharge percentiles from the USGS record (up to 4 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 | — | 0.1 | — | |
| February | — | 0.1 | — | |
| March | — | 0 | — | |
| April | — | 0 | — | |
| May | — | 0 | — | |
| June | — | 0 | — | |
| July | — | 0 | — | |
| August | — | 0 | — | |
| September | — | 0 | — | |
| October | — | 0 | — | |
| November | — | 0 | — | |
| December | — | 0 | — |
All values in cubic feet per second (cfs).
Common questions
- When does the Santa Cruz River run highest?
- January, on the long-term record at Santa Cruz River at Silverlake Rd, at Tucson, AZ — the furthest-downstream gauge Rivermatics tracks on this river. Median daily flow there is about 0.1 cfs that month, against 0 cfs in March, the lowest. Upstream gauges peak on their own schedule; the table on this page gives April and July for each.
- How many gauges are on the Santa Cruz River?
- Rivermatics tracks 8 USGS streamgages on the Santa Cruz River, across Arizona. Each has its own page with the site's full flow record and monthly normals. The river may carry other gauges that publish neither daily values nor discharge statistics; those are not tracked here.
- Is there a flow forecast for the Santa Cruz River?
- Yes, at 8 of the 8 gauges. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on each basin's observed flows, weather and snowpack, and issues a daily 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 each gauge's live screen.
- Can I use Santa Cruz River 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.