Big Sioux River at Akron, IA
River level and flood forecast · Plymouth County
Normal5.8 ftas of Mon 2 PM
The river is 10.2 ft below flood stage (16 ft).
Flow: 890 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 | 20 ft |
| Moderate flood stage | 18 ft |
| Flood stage | 16 ft |
| Action stage | 14 ft |
| Record crest (June 22, 2024) | 27.35 ft |
What floods at each level
From the National Weather Service, highest first.
- 26 ftThe western portions of Akron will be flooded with water reaching as far as the city park and baseball field to the downtown area, especially if water is able to come in through the storm drains.
- 25 ftThe lowest levees in Akron will begin to be overtopped if not sandbagged, resulting in more significant flooding in the western edges of Akron.
- 23.25 ftLevee gates at Riverside in Sioux City will be closed.
- 23 ftMuch of Highway 48 will be flooded on both sides of the bridge. Water begins to enter the northwest portions of Akron if levee protection fails, potentially flooding a couple of structures near the intersection of Hwy 48 and Hwy 12. Highway 50 near Westfield will be flooded, and the bridge east of Jefferson will be overtopped.
- 22 ftThe lower portions of the railroad tracks in Akron begin to flood if levee protection fails.
- 20 ftHighway 48/Big Sioux River Rd just west of Akron begins to flood as does the parking lot at the boat ramp in Akron begins to flood.
- 19.5 ftA few farm houses may begin flooding.
- 17 ftAbout 6500 acres of farm land are flooded.
- 16 ftSeveral farm levees are overtopped with significant flooding of agricultural lands.
- 15 ftSome rural roads on the South Dakota side of the river begin to flood.
- 12 ftSome very minor flooding of the lowest lying areas along the river begins.
Highest crests on record
- 27.35 ft — June 22, 2024
- 25.46 ft — June 18, 2014
- 23.94 ft — March 16, 2019
- 23.45 ft — June 23, 2018
- 23.38 ft — April 26, 2001
Recent crests: 11.49 ft (July 7, 2025) · 27.35 ft (June 22, 2024) · 17.97 ft (April 14, 2023) · 14.03 ft (June 1, 2022) · 11.45 ft (August 30, 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 (AKRI4); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.