Flood Plain Management
LifesaverThe Iowa Department of Natural Resources regulates construction on all flood plains and floodways in the state to protect life and property; and to promote the orderly development and wise use of Iowa's flood plains.

Flood Plain Development Permits
Permits are required for most work on the floodplains of streams and rivers throughout the State.  Visit our floodplain permitting page to learn more about the permitting process, checklists for project design, and instructions on our new online application system called PERMT.

Dam Safety
The Iowa DNR is responsible for the state's dam safety program. DNR staff review and approve the construction of new dams, maintain an inventory of existing dams that meet minimum size criteria and periodically inspect certain dams. Currently there are approximately 3,800 dams on the state's dam inventory. 

Flood Plain Development Regulations
Iowa Administrative Code contains several chapters that regulate development in Iowa's flood plains.  The regulations contain the minimum standards for projects located in Iowa's flood plains must meet. 

National Flood Insurance Program
The DNR works with communities and counties to develop and administer local floodplain management programs, coordinates the National Flood Insurance Program, and assists the Federal Emergency Management Agency and the Iowa Emergency Management Division in responding to flood disasters.

If you have questions about the DNR Floodplain and Dam Safety Section or the permitting process, please email floodplain-help@dnr.iowa.gov or you can call (866) 849-0321.  Please note that due to Covid19, you can only leave a message on this phone line at this time. 

Floodplain Mapping
The DNR, along with the Iowa Flood Center and other partners, is creating new, comprehensive, accurate floodplain maps for Iowa cities and counties. Starting in 2011, many Iowans will know if their property is at risk from flooding for the first time, as many Iowa communities have never had accurate floodplain maps.