Decision framework for the 2020 Lower Hunter Water Plan

With growing uncertainty around water security, the NSW Lower Hunter regional plan for a secure, resilient and sustainable urban water supply in coming decades needed to take into account a range of uncertainties and variation in factors – such as population growth, climate change, and rapid technological advances – to remain adaptive. Not doing so incurred the risk of investing substantially in infrastructure that could be obsolete, inadequate or inappropriate under changing conditions.

In collaboration with DoI and Hunter Water, ISF designed a practical 'Multi-adaptive Planning Framework' framework to support decision-making on a portfolio of options. The framework considered planning for multiple objectives (such as resilient water services, healthy waterways and urban greening) under potential combinations of disruptors (such as technology advancements) and risks. It brought together several key planning concepts and provided justification for investing in a range of immediate actions, including local recycling schemes and water efficiency measures, while keeping potential options open for further investment to respond appropriately to future risks.

The framework separated risks into shocks (extreme events such as a sudden change in the rainfall patterns requiring a step-change in management approaches) and predictable trends of population and temperature increases, and suggested different processes for testing against them. This ensured that the proposed system was flexible and resilient under the various conditions. The outcome of this framework leads to:

an investment portfolio of actions and measures for the current iteration of the plan, and
a suite of future options to consider is the planning assumptions change and/or when one of the objectives is not met.

The decision framework makes it possible for the Lower Hunter region to make more astute investment decisions and to keep its options open, thereby avoiding building large, inflexible assets that are potentially unsuitable in a rapidly changing context. The approach presented in the framework has application in the wider water sector for systematically considering a wide range of uncertainties in the planning process and accommodating possible changes in the planning assumptions about the future.