About Storm Watch

Source

Readings come from the Databricks view partners.sac_county.sac_flood_fact_vw. The app copies the full view into a local snapshot every hour. The Refresh data button reloads that snapshot on demand; it does not poll the gauges. If a refresh fails, the previous snapshot stays in place and a notice appears at the top of the page.

Snapshot

Last successful refresh

Nov 12, 2026, 2:40 PM PT

Readings in snapshot

81,805

Sites

Arcade@EMD (City) (Oct 5, 2026 to Nov 12, 2026); East Drain Canal (City) (Oct 5, 2026 to Nov 12, 2026); Magpie@Raley (City) (Oct 5, 2026 to Nov 12, 2026); Marysville Blvd (City) (Oct 5, 2026 to Nov 12, 2026); Morrison Creek (City) (Oct 3, 2026 to Nov 12, 2026); Morrison Creek at Sump 89 (City) (Oct 5, 2026 to Nov 12, 2026); NEMDC (City) (Oct 5, 2026 to Nov 12, 2026)

Measures

• Water depth (feet): how deep the water is above the channel bottom, as reported by the source. Elevation (feet NAVD88) is the sensor's water-surface reading and stays available in tables and downloads. Sites with no channel bottom set show elevation instead.
• Below sensor range: each sensor has a physical minimum it can report. At that minimum the depth is not measured; it is only known to be between 0 and the sensor's maximum possible depth (0.30 ft at Morrison Creek). Charts shade this band.
• Rain increment (inches): rain recorded since the previous reading (sensor class 10). Hourly, daily and 24-hour totals are sums of these values.
• Rain accumulation (inches): the gauge's running total (sensor class 11). It matches the sum of increments since data began.

Watch indicators

The site list highlights a few simple conditions so changing sites are easy to spot. They are descriptive, not flood stages or alert levels, because no such thresholds are defined in the source.

• Raining: rain recorded in the hour before the site's latest report.
• Rising or falling: the water level compared with the last reading at or before three hours earlier. Up 0.1 ft or more is rising, down 0.1 ft or more is falling, anything in between is steady. Water level sensors may report mainly when the level changes, so a long gap between level reports usually means no meaningful change. When the creek is below the sensor's range, the change reads “No measurable change”.
• Large jump: the source flagged a water level change of more than 0.5 ft since the previous report in the last three hours.
• No recent report: no sensor at the site has reported for longer than three times its usual reporting interval (never less than 2 or more than 12 hours). Any sensor counts, so a quiet water level sensor alone does not trigger it.
• Battery: OK at 12 V or more, low below 12 V, very low below 10 V, the lower limit noted for the Contrail system. The 12 V line is a working value for this app.
• Rain totals over 1, 24 and 72 hours add up Rain Increment readings only.

Limitations

• Some panels on the Home and Live pages still show sample data and are tagged "Sample data" until City systems are connected. Weather comes from the National Weather Service; rainfall, stream gauges and storm requests come from City data.
• Readings flagged AN appear when a water level changed by more than 0.5 ft from the previous report. The source does not document the data quality codes, so these are marked as large changes, not as errors.
• Values are provisional and have not been reviewed by the data owner.
• Readings arrive at irregular intervals; gaps are not interpolated.
• No flood stage or alert thresholds are defined in the source, so none are shown.
• All times are shown in Pacific time. Downloads use UTC.

Accessibility

This app targets WCAG 2.1 AA. To report an accessibility barrier or request the data in another format, contact the Data & Analytics Team. A team mailbox is pending.