Great Miami River at Hamilton, OH
River level and flood forecast · Butler County
The river is 11.8 ft below flood stage (75 ft).
Forecast to hold near 63.2 ft through Sat, Oct 17, 8 AM.
Flow: 1,910 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Mon, Oct 12, 10:22 AM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 89.5 ft |
| Moderate flood stage | 82 ft |
| Flood stage | 75 ft |
| Action stage | 73 ft |
| Record crest (March 19, 1943) | 76.6 ft |
What floods at each level
From the National Weather Service, highest first.
- 90 ftWater would overtop levees on the south side of Hamilton. Water levels exceeding 90 feet would top all levees protecting the business district resulting in major flooding near the river channel through the entire city. Major flooding occurs, especially near New Miami and Ross, where homes and businesses along the river are suffering major inundation.
- 89 ftThis elevation is at the top of some levees protecting mainly the southern areas of Hamilton. In addition to major inundation of communities such as New Miami and near Ross, river stages above this level would inundate some areas of Hamilton south of Pershing Avenue along and near Neilan Boulevard. Widespread inundation occurs near Joyce Park and Joe Nuxhall Lane.
- 84 ftFlooding worsens in lowland areas in southern Butler County between State Route 128 and the Great Miami River. Flooding also worsens along the river near Ross. The City of Hamilton itself is protected from river flooding up to 89 feet for locations in the southern part of the city, with most of the city protected at stages up to 90 feet.
- 82 ftLowland areas in southern Butler County between State Route 128 and the Great Miami River become flooded. Flooding also occurs along the river near Ross. The City of Hamilton itself is protected from river levels up to 89 feet in the southern sections of the city, while most of the city is protected up to 90 feet.
- 77 ftLocations along the river mainly south of the City of Hamilton become flooded. Flooding continues to impact New Miami and Ross. Southern portions of the City of Hamilton are protected by flood walls up to 89 feet, with the majority of the city protected up to a stage of 90 feet.
- 75 ftLowland areas south of Hamilton to Ross continue to flood. Evacuations are possible near New Miami and near Ross. The City of Hamilton itself is protected from river levels up to 89 feet for locations in the southern part of the city, with most of the city protected at stages up to 90 feet.
- 74 ftLowland flooding begins about one mile north of High Street in Hamilton and near Ross, about five miles downstream. Low-lying homes near New Miami and other low-lying areas along the river channel are impacted. The City of Hamilton itself is protected from river levels up to 89 feet for locations in the southern part of the city, with most of the city protected at stages up to 90 feet.
Highest crests on record
- 76.6 ft — March 19, 1943
- 76.5 ft — February 26, 1929
- 76.33 ft — January 22, 1937
- 75.95 ft — January 27, 1952
- 75.84 ft — January 5, 2004
Recent crests: 73.53 ft (April 5, 2025) · 75.15 ft (March 19, 2008) · 72.87 ft (January 14, 2005) · 75.57 ft (January 6, 2005) · 75.84 ft (January 5, 2004)
Up and down the river, and nearby
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (HAMO1); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.