Auxiliary Spillways

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Learn more about the importance of spillway design criteria at DamFailures.org

“An auxiliary spillway is infrequently used and may be a secondary spillway (augmenting a service spillway discharge capacity). During operation there could be some degree of structural damage or erosion to the auxiliary spillway due to releases up to and including the maximum design discharge. Auxiliary spillways may be less robust, erosion-resistant structures consisting of some cast-in-place reinforced concrete, riprap channel protection and/or unarmored excavated channels”.

Life Cycle of Auxiliary Spillways

• Design and Construction of Auxiliary Spillways
• O&M of Auxiliary Spillways

Examples

Learn more about the importance of spillway design criteria at DamFailures.org

Best Practices Resources

Selecting and Accommodating Inflow Design Floods for Dams (FEMA P-94) (Federal Emergency Management Agency)

Technical Release 210-60: Earth Dams and Reservoirs (Natural Resources Conservation Service)

National Engineering Handbook: Chapter 21 - Design Hydrographs (Natural Resources Conservation Service)

National Engineering Handbook: Chapter 50 - Earth Spillway Design (Natural Resources Conservation Service)

Hydraulic Design of Spillways (EM 1110-2-1603) (U.S. Army Corps of Engineers)

Design Standards No. 14: Appurtenant Structures for Dams (Ch. 3: General Spillway Design Considerations) (Bureau of Reclamation)

Design of Small Dams (Bureau of Reclamation)

Engineering Guidelines for the Evaluation of Hydropower Projects: Chapter 2- Selecting and Accommodating Inflow Design Floods for Dams (Federal Energy Regulatory Commission)

Trainings

On-Demand Webinar: Introduction to Addressing Inadequate Conveyance Capacity at Dams

On-Demand Webinar: Inspection and Assessment of Spillways

On-Demand Webinar: Inlet and Outlet Hydraulics for Spillways and Outlet Structures

Citations:

Revision ID: 4854
Revision Date: 12/02/2022