2027 Webinar: Understanding and Optimizing Riser and Outlet Structure Performance

Speakers: Amanda Hess, PE, GFT, Vice President, Geotechnical, Dams and Hydraulics

PDHs: This webinar is eligible for 2 PDH credits.

Understanding and Optimizing Riser and Outlet Structure Performance explores the role of riser and outlet structures in dam safety, reservoir operations, and regulatory compliance. This webinar examines the multiple purposes these structures serve—from normal releases and water supply to emergency drawdown—and the performance requirements they must meet under a range of operating conditions. Attendees will gain a practical understanding of the hydraulic controls governing riser and outlet behavior, including inlet, barrel, and outlet control, and how discharge is computed through these systems.

Building on these fundamentals, the webinar also acknowledges strategies to maximize the performance of both existing and proposed facilities. Topics include improving hydraulic efficiency through inlet modifications and evaluating the impacts of sliplining. The webinar will also address design considerations such as aeration and venting and terminal energy dissipation. 

Key Takeaways: 

1. What purposes do riser/outlet structures serve?

2. What requirements must riser/outlet structures meet?

3. What controls the hydraulics of riser/outlet structures?  How do you compute discharge through a riser/outlet structure?

4. How can you maximize existing and proposed facilities and ensure proper functioning

5. How can a riser structure design account for energy losses in the riser and outlet system and provide energy dissipation at the terminus?