Where the water stands right now against the four official thresholds:
| Flood stage | Level (ft) | What it means |
|---|---|---|
| Major flood stage | 12.5 | extensive inundation and significant evacuations — a serious event |
| Moderate flood stage | 11.5 | some buildings and roads inundated; evacuations possible |
| Minor flood stage | 9.5 | low-lying roads and fields near the river start to flood |
| Action stage | 8 | water is approaching flood level — time to pay attention |
The National Weather Service has no historic crest list on file for this gauge.
The marker is this gauge; nearby gauges load live and are clickable.
The live reading at the top of this page answers that: the gauge is compared against its official NWS flood stages every 15 minutes. Minor flooding at this gauge begins at 9.5 ft. Blue means normal, yellow is action stage, orange minor, red moderate and dark red major flooding.
major flood stage 12.5 ft, moderate flood stage 11.5 ft, minor flood stage 9.5 ft, action stage 8 ft. These are official National Weather Service thresholds set specifically for this gauge, not generic values.
From the NOAA National Water Prediction Service, the official U.S. river gauge network — a U.S. government work in the public domain. Live stage is refreshed every 15 minutes; flood thresholds and historic crests are refreshed monthly. For life-safety decisions follow NWS Rapid City and local emergency management.