About FlowIowa
FlowIowa is a live, animated map of every USGS river gauge in Iowa, plus the Mississippi, Missouri and Big Sioux rivers along its borders. At a glance it shows which rivers are running high, which are low, and where water is moving.
How to read the map
Each river is coloured by how its flow right now compares with the same calendar day across that gauge's history, often decades of records. So "high" means high for mid-October, not high compared with a spring flood.
- Amber to fire: running low, below most years for the date
- Calm teal: about normal
- Electric blue to white: running high
- Magenta pulses: at or above National Weather Service flood stage
Light pulses travel downstream faster as flow rises. Click any gauge for its river level, flow, flood stages and, where available, the National Weather Service forecast. Press space or the play button to replay the past week.
Three maps
- Flow: river levels, flow, flood stages, water temperature and, at about a dozen gauges, nitrate.
- Grow: soil temperature and soil moisture from Iowa State University's soil stations, with U.S. Drought Monitor areas.
- Blow: wind, air temperature, humidity and rainfall from Iowa's airport weather stations, with extra rain gauges from the ISU soil stations.
Past events replays the biggest Iowa floods and droughts on record, including 1993 and 2008, on the same map.
Where the data comes from
- River levels, flow, water temperature, nitrate and long-term daily statistics: U.S. Geological Survey
- Flood stages and river forecasts: NOAA National Weather Service
- Soil, airport weather and rainfall: Iowa Environmental Mesonet, Iowa State University
- Drought areas: U.S. Drought Monitor
- River network: NHDPlus, via the U.S. EPA
The map refreshes about every hour. Most readings are provisional: the agencies that publish them review and sometimes revise them later.
Not for emergencies
FlowIowa is an independent project and isn't affiliated with any of the agencies above. It's built for understanding and curiosity, not for safety decisions. During a flood, follow the National Weather Service and your local emergency officials.
Contact
Questions, ideas or a reading that looks wrong? Email [email protected].