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Dam Safety and Risk MAP/Flood Mapping Studies Fact Sheet Series

Cover photo for the document: Dam Safety and Risk MAP/Flood Mapping Studies Fact Sheet Series

The Dam Safety Fact Sheets below were developed by FEMA Region IV and provide information on risk communication and the residual risk of dams in Risk MAP, dam considerations in flood mapping studies, and dam safety awareness.

Dam Considerations in Flood Mapping Studies: Whether for flood control, water supply, or recreation, dams play an important role in serving the community and managing a natural resource, but there are hazards and risks to consider when large volumes of water are stored. Sharing information about dams during a flood mapping study can help stakeholders obtain a more complete picture of the risks within a floodplain. 

Considering the Residual Risk from Dams in Flood Risk Products: During a flood mapping project, to properly assess and communicate a complete view of the flood risk both upstream and downstream of a dam, it is critical to consider the effects of dams and their associated residual risk. Many large reservoirs are operated with outflow controls that include gates to regulate the flow through outlet structures. Dam outlet control structures can affect flow rates downstream regardless of the dam’s purpose. Even when dams perform as they are designed, there will always be a level of flood risk remaining, or “residual risk.” 

Risk Communication for Dams in Risk MAP: Risk communication can help increase knowledge, understanding, and awareness of dams and the risks they pose. While dams can serve many purposes, such as flood risk reduction, hydropower generation, water supply, and recreation, many people in communities near dams are unprepared to deal with the impacts of a dam failure or dam-related flooding. It is important to be aware that risk can come from many modes of failure, or even from conditions in which the dam has not failed at all.

Dam Safety Awareness: Increased awareness of dams and the risks they pose is an important part of dam risk management. Hazards from dams can be triggered by severe weather events, improper operation of the dam, or regular or emergency releases of water downstream.

SizePublication Date
Icon for file of type application/pdfDam Considerations in Flood Mapping Studies
1.50MNovember 28, 2018
Icon for file of type application/pdfConsidering the Residual Risk from Dams in Flood Risk Products
2.14MNovember 28, 2018
Icon for file of type application/pdfRisk Communication for Dams in Risk MAP
1.39MNovember 28, 2018
Icon for file of type application/pdfDam Safety Awareness
3.49MNovember 28, 2018