Completed: March 2023.
Funding: Federal Emergency Management Agency.
Committee Overlap: Mapping & Engineering Standards.
Floodways are a tool that may be provided to communities by FEMA to assist in the community’s floodplain management. Communities are routinely provided floodways that include a surcharge without information on the impact of the surcharge. This packet is intended to provide information to communities so that they can make an informed decision regarding a floodway surcharge standard that meets their community’s acceptable level of risk and possibly improve the resiliency of their community.
The information provided herein is intended to improve community understanding of the possible impacts of floodway surcharge. Materials enclosed in this packet include a short summary sheet that clearly defines a floodway, floodway surcharge, and the impacts of floodway surcharge and a graphical representation of how floodway surcharge is developed that can be used in PowerPoints slides.
The materials also include some best practices that can be implemented to minimize increases in risk to existing development.
An Introduction to Floodway Surcharge: An Outreach Packet (2023)
Understanding Floodway Surcharge Graphic [Powerpoint]
Related projects:
2D Modeling Guidance - 2025
Impacts of Floodway Surcharge - 2024
Floodway Encroachment Standard: Minimizing Cumulative Adverse Impact - 2013