Where the water stands right now against the four official thresholds:
| Flood stage | Level (ft) | What it means |
|---|---|---|
| Major flood stage | 6 | extensive inundation and significant evacuations — a serious event |
| Moderate flood stage | 4 | some buildings and roads inundated; evacuations possible |
| Minor flood stage | 2 | low-lying roads and fields near the river start to flood |
| Action stage | 1 | 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 2 ft. Blue means normal, yellow is action stage, orange minor, red moderate and dark red major flooding.
major flood stage 6 ft, moderate flood stage 4 ft, minor flood stage 2 ft, action stage 1 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.