Considerations for Addressing Floodplain Management for Dam Rehabilitation or Removal Projects

ABSTRACT ONLY - Modifications in the floodplain are subject to various local, state, and federal regulations. Dam rehabilitation or removal projects are subject to these regulations because they are physically located in floodplains and impact the hydrologic and hydraulic performance of the stream system. Dam modification or removal projects may alter the extent and timing of flood flows and the flood elevations both upstream and downstream of the structures. Focusing only on the federal regulations related to floodplain management and the impacts of dam rehabilitation or removal projects, three areas of regulations apply: National Flood Insurance Program (NFIP) regulations; Executive Order 11988; National Environmental Policy Act (NEPA).

This presentation will summarize the composite floodplain management requirements of the three aforementioned areas of regulations as they relate for dam rehabilitation or dam removal projects. The summary may be helpful as a checklist best initiated during project planning and updated through design and then construction to incrementally address the floodplain management impacts of a dam rehabilitation or dam removal project.