Dr Moyes questions the justification for Tillegra Dam
Back in November 2006, the NSW Government announced that Hunter Water would construct a new dam at Tillegra as an integral part to secure the water future of the Lower Hunter region for the next 60 years. Subject to receiving the necessary approvals, the proposed 450 billion litre dam is to be built in the upper Williams Valley (north of Dungog) at an estimated cost of $477 million, up from the original cost of $300 million. The new Tillegra Dam is expected to be supplying water to the Lower Hunter by 2013.
Earlier this month, an independent analysis into water supplies to the Hunter Valley has found that there is a one-in-a-million chance of current water supplies being low enough to justify building a proposed dam.
The Institute for Sustainable Futures (ISF) in the University of Technology Sydney released “An Independent Review of the Need for Tillegra Dam” Report which found the NSW Government prevented IPART, the independent economic regulator for NSW, from examining whether the proposed dam was needed or not.
According to Professor Stuart White, Director of ISF, the results of the study overwhelmingly demonstrate that the proposed Tillegra Dam is an expensive, unnecessary and wasteful approach by the government to securing the region’s future water needs. Professor White believes that the region is in no immediate danger of water shortages.
He sated: “The NSW Government has stated that Tillegra Dam is necessary to drought proof the Hunter, however the reasons given for the dam are unsupported by the evidence and are unsound. In fact, if water conservation initiatives are expanded to similar levels to Sydney’s it will be 2050 before any new supply options need even be considered. The region is in no immediate danger of water shortages, so there is plenty of time for a full and open process to create a sustainable, urban water strategy that also includes genuine community consultation.”
There are four reasons that have been given by the NSW Government and Hunter Water Corporation for building the Tillegra Dam.
1. Supply for the Central Coast. In the year after the dam’s announcement, the Gosford-Wyong joint water authority on the Central Coast was given $80 million federal grant to augment their existing water supply system with a new pipeline from Mardi to Mangrove. This means that the region can satisfy its own water supply needs for the next 40 years.
2. Climate Change. Hunter Water has stated that long-term climate change is a key reason for building the dam. Without regional climate analysis, it has assumed there will be a 10 percent reduction in rainfall. Applied simplistically, this assumption translates to a reduction in run-off of approximately 25 percent.
However, region-specific modelling, conducted by the NSW Government, predicts that in the Hunter Region, climate change will see slight increases in both rainfall and run-off and that these factors are likely to more than offset an expected increase in evaporation. This prediction is confirmed in the most recent regional climate change modelling by the University of Newcastle which found no significant change in rainfall or runoff in the Hunter in their forecasts to 2080.
3. Drought security in the Lower Hunter. The current water supply in the Lower Hunter has been shown to have high levels of drought security. Hunter Water estimates that there is only a one in a million chance of supplies falling to critical levels in any given year. Analysis by SKM Consulting Engineers also shows that the existing demand system will retain high levels of drought security with increased levels of demand. Since the early 1980s, there have been no water restrictions imposed on consumers in the Lower Hunter and drought security is at 30 year high due to decreased consumption and increased storage volumes.
4. Long-term supply for the Lower Hunter. The Institute for Sustainable Futures report found that water consumption in the Lower Hunter in 2007/08 was the lowest recorded for 40 years, at 67 GL, and the five-year average was 70 GL per year, which is trending downwards from earlier decades.
The review also found that Hunter Water has unnecessarily reduced its estimate of available supply for the existing supply system from 90 GL to 67 GL per year. Water demand forecasts by Hunter Water Corporation appear overestimated and more realistic projections show that with demand management, water consumption in the Lower Hunter could remain well below 90 GL per year until 2050. Supply capacity and drought security for the Lower Hunter has been increasing for several decades.
Rev the Hon. Dr Gordon Moyes said, “The contents of the report shows further evidence that Lower Hunter is far from an emergency situation with regards to either long term water supply or drought security. This is a clear signal to the NSW Government to revoke its plans to build Tillegra Dam. This is an opportunity for the NSW Government to genuinely consult and involve the community and stakeholders on urban water strategy in the Lower Hunter”.
Dr Moyes commented, “The announcement of Tillegra Dam was not based on water resource planning but for political reasons. The NSW Government wishes to secure electorate votes both in the Central Coast and Hunter region.” The NSW Government announced its intention to build the project on November 13, 2006 five days after former NSW Aboriginal Affairs minister Milton Orkopoulos was charged with 30 child sex and drugs offences.
Furthermore, IPART estimated that for an average quarterly bill there will be an increase of approximately $30. Hunter Water Corporation has announced on its website that new costs take effect as of July 2009. In January 2009, the Newcastle Herald reported that approximately 13,000 Hunter Water ratepayers are on payment plans. This staggering figure reflects the financial hardship experienced by families and pensioners in the region.
Dr Moyes concluded, “With the connection of the Central Coast’s two main dams by a large pipeline coupled by the rational reasoning outlined by the ISF Report, there is no need for the construction of Tillegra Dam.”
Reference: An Independent Review of Supply-Demand Planning in the Lower Hunter and the Need for Tillegra Dam, Institute of Sustainable Futures, The University of Technology Sydney, August 2009.