- More than 47,000 properties in 22 cities and five counties
- 1 Million people
- More than $10 billion worth of buildings and land
- 11 hospitals
- 60+ schools and colleges
- 814 miles of public roads
- 14 wastewater treatment plants
- 9 water treatment plants
- Drinking water resources|
- Outdoor recreation
Our Main District is responsible for an integrated flood protection system that significantly reduces flood risk to property owners across five counties including riverfront communities along the Great Miami River and its tributaries.The system includes five dry dams, storage basins, 55 miles of levees, and preserved thousands of acres of floodplain. Together, the dams have stored floodwaters more than 2,100 times since construction was completed in 1922. The Miami Conservancy District's flood protection system is known around the U.S. and the world.
If a property is protected by dams, storage basins, and levees, it is considered fully protected. If a property is protected by dams and storage basins (no levees in your community), it is considered partially protected, and receive less benefit. Properties that flooded in 1913 and are now protected by the Miami Conservancy District flood protection system pay an annual assessment calculated using several factors including property tax values established by the county auditor. Full & Partial Protection Maps by County:
Integrated Flood Protection System
The integrated system for dams, levee systems, storage basins, floodplains, and improved channels, work together to deliver a systems-based solution to prevent catastrophic flooding. The flood protection system is designed to manage a storm the size of the Great Flood of 1913 (9-11 inches of rain in three days across the 4,000-square-mile watershed) PLUS an additional 40 percent.
The dams are regulated by the Ohio Department of Natural Resources (ODNR) and inspected regularly.
Levee Accreditation
When the Federal Emergency Management Agency (FEMA) updates floodplain mapping, levees must be reaccredited so the updated maps continue to recognize the levees as providing flood protection to the communities. As the levee owner, the Miami Conservancy District must provide sufficient information to demonstrate that the levee complies with all accreditation requirements. The information and documentation submitted to FEMA must be certified by a professional engineer.
FEMA staff notified MCD in 2020 that it was completing updated hydrologic and hydraulic analyses of the Great Miami River in Montgomery County. The updated analyses could lead to remapping and a requirement to reaccredit levees in Huber Heights, Dayton, Moraine, West Carrollton, and Miamisburg. Data was collected in 2023 and 2024 for submittal to FEMA in 2025 to accredit the levees.
