HUD website on executive order 11988
HUD’s regulations in 24 CFR Part 55 outline HUD’s procedures for complying with EO 11988. Part 55 applies to all HUD actions that could be harmed or cause harm if located in a floodplain, including but not limited to proposed acquisition, construction, demolition, improvement, disposition, and financing actions under any HUD program. The purpose of Part 55 is not in most cases to prohibit actions in a floodplain, but to provide the method for HUD projects to comply with EO 11988 and avoid unnecessary impacts. Includes a Coastal zone management worksheet and a flowchart that outlines the steps needed to comply with part 55.
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Federal register text of the EO - View Link
FEMA's page -
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