Guidance for Flood Risk Analysis and Mapping: Floodplain Boundary Standards (FBS) [open pdf - 959KB]
From the Overview: "This document provides guidance for the implementation of Floodplain Boundary Standards (FBS), and the preparation for and performance of audits of compliance as part of the Risk MAP [Mapping, Assessment, and Planning] program. The reliability of the floodplain boundary delineation is quantified by comparing the computed flood elevation to the ground elevation at the mapped floodplain boundary."
Guidance Document 49
U.S. Federal Emergency Management Agency: https://www.fema.gov/