What is a floodplain?
A floodplain is an area adjacent to a river, creek, lake, stream or other waterways that is subject to flooding when there is a significant run-off event.
The technical definition of a floodplain as it pertains to the development process can be found in Ada County Ordinance 835.
What do I need to know if my property is in a floodplain?
- Any development within the Floodplain will require a Floodplain Development Permit.
If you are considering development within a Floodplain, please view the entire Flood Hazard Overlay District Ordinance. The floodplain Submittal Checklist along with a Master Application includes everything you need to submit an application. Please feel free to contact the Ada County Engineer at (208) 287-7925 with any questions you may have.
Where can I get more information:
- View our Frequently Asked Questions (FAQs)
- View our Flood Hazard Overlay District Ordinance: Ordinance 835
- Download our Master Application and Submittal Checklist
- Contact FEMA
- Find a registered Professional Engineer licensed in Idaho
Development Services
Ada County Courthouse
200 W. Front St., Boise, ID 83702
Phone: (208) 287-7900, FAX (208) 287-7909