Victorian Climate Initiative Water Corporation Perspective Jolyon - PowerPoint PPT Presentation

Victorian Climate Initiative Water Corporation Perspective Jolyon Taylor Senior Water Resources Engineer www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

Gippsland Water’s Region www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

VicCI and Guidelines • How does a Water Corporation use VicCI findings? • A major use is the 5 yearly Urban Water Strategy (UWS). • For this, DELWP summarised the VicCI outcomes into a set of Guidelines, with ten clear recommendations. www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

Water Supply - Level of Service • Urban Water Corporation primary function is meeting customer service obligations. • One level of service (LOS) criteria is reliability of supply, now and into the future, i.e. how often is supply restricted, for how long, and to what degree? • How reliable should a water system be? • Water Corporations are given freedom to determine acceptable LOS in consultation with customers. • This forms a key step in the UWS development. • Gippsland Water’s target is 95% reliability, or water restrictions on average once every 20 years. www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

LOS and Climate • How do we know if our systems will meet this target, now and into the future? • We could look at historic performance, BUT … things are changing. • Climate • New climate baseline. • Possible step climate change. • Ongoing gradual climate change. • Infrastructure and entitlement changes. • Changing demand levels. • We need a water model. www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

Water Model What should we use for Inflows inflows? Infrastructure Rules River Demand (downstream uses) www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

Inflow Scenarios • The most significant use of the VicCI findings is in developing appropriate inflow scenarios to model. • Using the 10 recommendations in the Guidelines, we can: • Adjust historic streamflow records to reflect a range of possible climate scenarios. • Current climate. • 3 gradual future climate scenarios (low, medium, high). • Step climate change. • While retaining the value of the natural variability inherent in our historic flow records. • This ensures we consider the impacts of both climate variability and climate change. www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

Water model results • Running our model for the historic record period but with adjusted inflows, we can test our systems for reliability. • Did customers get restricted? If so… • How often? • How severe? • For how long? • Did the system meet the target LOS? • Might it fail to meet target LOS in the future? • Do we need to do something and when? www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

Example System Forecast www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater

Gippsland Water would like to acknowledge the significant and important work undertaken by the VicCI team. The ongoing review of climatic and hydrologic scientific developments, and their translation into useful guidance, helps water corporations meet their customer obligations. Thankyou. www.gippswater.com.au | facebook.com/gippslandwater | twitter.com/gippswater