There are two types of dams and reservoirs. Industrial water retention dams and reservoirs are used for storing solids and the water associated with the particular industrial process such as tailings, slime and other similar industrial materials. The second type is conventional dams and reservoirs.
Dam Classifications
Dams and reservoirs are further classified by the downstream environment zones.
- Class I - Contains 10 or more permanent dwellings or any public building.
- Class II - Contains one to nine permanent dwellings or one or more campgrounds with permanent water, sewer and electrical services or one or more industrial buildings.
- Class III - Everything else.
Spillway design standards are based on the downstream environment zones. If development increases downstream from a permitted dam, the department’s staff will make a judgment regarding whether or not the new development warrants changing the dam’s downstream hazard classification zone to a higher class during the renewal or construction application process.
Dam Information
The department and others provide information about dams in Missouri. The type and amount of information available depends on the dam's height.
- Dams less than 25 feet in height are unregulated in Missouri. These dams are generally not accounted for and detailed information is not available.
- Dams greater than 25 feet in height, but less than 35 feet in height are unregulated in Missouri. However, these dams are accounted for and information is collected for the National Inventory of Dams. The inventory provides information about the dam's name and location, purpose, type and size.
- Non-agricultural and non-federal dams 35 feet or greater in height are regulated in Missouri. These dams require a permit for construction and operation. Information about these dams can be found in the National Inventory of Dams. For information about obtaining the required permits, visit Dam and Reservoir Safety Permits.
Basic and locational information about regulated and unregulated dams in Missouri is also available in the department's Geosciences Technical Resource Assessment Tool (GeoSTRAT) ArcGIS web application.