Principal Spillways

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Also known as “Service Spillways” according to the United States Bureau of Reclamation: “A service spillway provides continuous, or frequent regulated, or staged releases (controlled) or unregulated (uncontrolled) releases from a reservoir without significant damage to the dam, dike, or appurtenant structures due to releases up to and including the maximum design discharge. Service spillways are typically very robust, erosion-resistant structures consisting of mostly cast-in-place reinforced concrete and riprap channel protection”.

In many cases, these spillways include closed conduits and function as both a service spillway and outlet works.

Life Cycle of Principal Spillways

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

Best Practices Resources

Design Standards No. 14: Appurtenant Structures for Dams (Ch. 3: General Spillway Design Considerations), USBR

Citations:

Revision ID: 7137
Revision Date: 07/11/2023