Monona-Harrison Ditch near Turin, IA
River level and flood forecast · Monona County
Normal4.8 ftas of Mon 3 PM
The river is 18.2 ft below flood stage (23 ft).
Flow: 141 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Sun, Dec 31, 6 PM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 28 ft |
| Moderate flood stage | 25 ft |
| Flood stage | 23 ft |
| Action stage | 21 ft |
| Record crest (March 15, 2019) | 26.12 ft |
What floods at each level
From the National Weather Service, highest first.
- 29.5 ftWater reaches the bottom of the bridge at the gage site.
- 28 ftWidespread flooding of agricultural community would occur across the entire basin in which the Monona-Harrison Ditch as well as the Little Sioux River run. Both water channels run parallel with one another across most of Monona County and the northwest corner of Harrison County before joining the Missouri River.
- 25 ftWater overtops the levee system causing flooding of only surrounding agricultural fields and may overrun part of County HWY E54.
- 23 ftWater overtops the natural banks indicative of minor flooding but remains within the levee.
Highest crests on record
- 26.12 ft — March 15, 2019
- 24.8 ft — June 18, 1984
- 22.94 ft — March 18, 1986
- 22.61 ft — June 22, 1996
- 21.9 ft — March 19, 1978
Recent crests: 7.99 ft (August 6, 2025) · 20.26 ft (June 27, 2024) · 15.02 ft (February 28, 2023) · 5.77 ft (December 16, 2022) · 8.42 ft (March 24, 2021)
Up and down the river, and nearby
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (TRNI4); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.