2022 – Towards industry guidelines on reservoir evacuation for Australian dams

Marius Jonker -Aurecon Australasia Pty Ltd, Glen Hobbs – Glen Hobbs & Associates, Frank Nitzsche – GHD Pty Ltd, David Law – Entura

Several publications over the past three decades deal with the requirements for emergency evacuation of storages to intervene during a safety incident.

All dams are equipped with bottom outlet works for various purposes. There is however no uniform approach for designing and assessing the adequacy of the outlet capacity. The commonly used guidelines for sizing outlets for emergency evacuation predate contemporary risk frameworks for managing dam safety. A fresh approach is required that is aligned with modern dam safety practices.

This paper presents an approach that is aligned with Australian practices and is being considered for inclusion in the new ANCOLD Guidelines on Outlet Works. This paper also presents guidance on using some existing international guidelines for sizing outlet works in the context of Australian practices, as aligned with ANCOLD consequence categories and risk frameworks.

Guidance is provided on typical facilities for increasing the capacity for existing dams with insufficient outlet capacity.