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SW2015.03 USGS Flood-Inundation Map Development and Documentation Standards

Introduction and Purpose

The U.S. Geological Survey (USGS) is a leader in flood-inundation modeling and mapping. Flood-inundation maps (FIMs) show inundation extent, and in some cases inundation depth, for a wide range of streamflows and are distinguished from Federal Emergency Management Agency Flood Insurance Rate Maps in that they show inundation extent for specified water stages at an existing streamgage rather than annual exceedance probability flood flows.

Because of the range of data, approaches, and modeling tools available for the creation of inundation maps, the USGS National Flood Inundation Mapping (FIM) Program (URL: http://water.usgs.gov/osw/flood_inundation/ [link or image removed]) [link or image removed] coordinates the USGS FIM activities. Through the FIM Program, USGS has developed and enhanced several methods for inundation map creation and display. The FIM Program also developed and maintains the USGS interactive webbased FIM mapper, and provides resources and tools for USGS offices and partners to develop inundation maps.

The purpose of this policy memorandum is to establish minimum standards for FIMs included in the USGS FIM database and displayed through the USGS FIM mapper. The USGS [link or image removed] Flood Inundation Mapping Science tool box [link or image removed] contains additional information and tools.



It is the policy of the USGS to publish only those flood inundation maps that meet USGS standards.  These standards are consistent with those of USGS Integrated Water Resources Science and Services (IWRSS) partners. FIM standards are described below. The USGS will only host FIMs that meet standards and reflect the current hydraulic conditions of the mapped river reach.


USGS FIM Standards and Documentation Requirements

In general, inundation maps should be developed and documented using guidelines described in the report NOAA Partnered Guidelines for the Development of Advanced [link or image removed] Hydrologic Prediction Service Flood Inundation Mapping [link or image removed]. [link or image removed]  The NOAA guidelines Quality Assurance/Quality Control checklist (Appendix B) is available in Microsoft Excel format in the [link or image removed]USGS FIM Toolbox [link or image removed]. [link or image removed] Additional modeling and mapping tools and a list of qualified modelers and reviewers are also available in the Toolbox.

Section 3.2.2., Section 3.5., and Appendix D in the NOAA Guidelines are superseded by the USGS Report Templates and Mapping Application Submission Guidance and Templates listed in the USGS FIM toolbox. Sections 2.4.1(reach length), 3.3.1 (levee modeling), and 3.3.2 (structure depiction) should be considered but require interpretation and may be applied at the discretion of the local project team following good professional practices. Exceptions from and clarifications to the NOAA guidelines are described below.  

Optional information and Services

The USGS FIM mapper allows for the spatial display of flood-loss estimation data generated with FEMA’s Hazus model. These data are optional but if they are created with local community inputs, can provide very valuable information to planners and first responders.

More information on how the services function can be found in the USGS FIM webpage. Documentation and submission templates are listed in the USGS FIM Toolbox.


FIM Submission Procedures

In order to submit a flood inundation map library to the USGS FIM Program, the modeling, mapping and documentation report must follow the USGS Fundamental Science Practices requirements in [link or image removed] Survey Manual Chapter 502.3 [link or image removed]. [link or image removed]

Prepare map library files using the submission guidelines in the [link or image removed] USGS FIM Toolbox [link or image removed] for posting in the peer-review mapper. Please use the peer-review mapper to assist the reviewers and document the review process. Additional step-by-step processes are available in the submission guidance.

Submit files following the submission guidelines to the USGS National FIM Program Coordinator. Beginning in FY15, the USGS Water Mission Area will support the posting and maintenance of the FIM libraries and mappers.


For any questions and/or comments, please contact Marie Peppler at mpeppler@usgs.gov or 703-648-5314.





Robert R. Mason, Jr.

Chief, Office of Surface Water


Distribution:  GS-W All