R.A. Ayre and T. L. McGrath
The regulatory environment of Queensland’s water resources has changed significantly within the last few years as a consequence of the passing of the Water Act 2000. SunWater, as the owner of referable dams and the operator of water infrastructure, is required to observe the provisions of the new Act.
SunWater has undertaken dam failure analyses of a number of its dams in accordance with the new guidelines prepared by the Department of Natural Resources and Mines. The results of these assessments are being used as part of a portfolio risk assessment of its assets to help prioritise refurbishment activities. Aspects within the guidelines relate to various ANCOLD publications, with a focus on the consequence of failure for determining incremental hazard categories and appropriate design standards for spillway adequacy.
SunWater also operates its schemes under the provisions of Interim Resource Operation Licenses (IROLs). As part of Government’s water planning process, SunWater is required to submit proposed water management arrangements for its schemes. SunWater develops these arrangements, which include operation, water trading, and monitoring rules, to meet its business objectives and the objectives of government. With government approval, these proposed arrangements will translate to the provisions of Resource Operation Licenses when the Resource Operation Planning (ROP) process is completed.
This paper describes SunWater’s experience and approach to meeting regulatory requirements in the above areas.
— OR —
Now showing 1-12 of 31 2966:
J.H. Green, P.E. Weinmann, G.A. Kuczera, R. J. Nathan and E.M. Laurenson
Assigning an Annual Exceedance Probability (AEP) to the Probable Maximum Precipitation (PMP), and subsequently to the PMP Design Flood, is an integral part of the risk assessment process for large dams. Laurenson and Kuczera (1998) conducted a review of existing PMP risk estimation practices in Australia and concluded that, in the absence of any better information, the work by Kennedy and Hart (1984) provided the most appropriate estimates to adopt but with the proviso that the method should be viewed as interim pending the outcomes of ongoing research.
This paper gives an overview of a joint research project that is working towards obtaining credible estimates of exceedance probabilities of extreme rainfalls using the concept of storm arrival probability and storm transposition probability. It also outlines the work to be carried out over the next 12 months that will culminate in the combining of the outcomes of the two components and the application to test catchments. Finally, the paper discusses desirable follow-up action to promote the adoption of the research results by practitioners.
H. Morrison, J. Leckie, P. Richardson, R Paton
Awoonga Dam is a 40 metre high concrete faced rockfill dam on the Boyne River near Gladstone in Central Queensland. The dam supplies domestic and industrial water to the Gladstone region and the Callide Power Station. Stage 1 will increase FSL by 10 metres to EL 40, which increases storage capacity from 289,000 ML to 777,000 ML. To provide for future industrial growth in the region, the dam design facilitates future raising up to a nominated FSL of EL 62, in a number of stages.
The project consists of:
Significant savings were realised by adopting the alliances project delivery method, resulting in completion 5 months ahead of program and more than 10% under budget.
This paper details development of the project under the alliance and outlines some of the lessons learnt.
G.W. Ashman, C.M. Hamilton and N.J. Hall
Consideration of the need to accommodate environmental flows in the operation of major dams is a relatively new requirement in South Australia. Recognition of environmental water requirements has been promoted through the COAG water industry reforms and the State Water Resources Act. The South Australian Water Corporation is working with other Government agencies on environmental flow projects that will potentially involve three of the Corporation’s large dams. This presentation will summarise the work done to date on establishing environmental flow releases from these storages. The presentation will give the SA Water perspective on the regulatory, environmental, social and operational aspects of the environmental flow issue.
Richard R. Davidson, Shane McGrath, Adrian Bowden, Andrew Reynolds
Goulburn-Murray Water (G-MW) manages thirteen major dams for the State of Victoria. As part of its Dam Improvement Program (DIP), five priority dams were identified for detailed safety and performance evaluation. Over the last three years, the design reviews have been completed and a series of dam safety issues have been identified which pose societal and financial risk. Substantial financial resources will be required to be applied over a considerable period to bring these dams into compliance with established international and Australian standards. Which of these dam safety issues should be addressed first? In what sequence and with what urgency should the actions be implemented? Can cost-effective interim targets be set? How can the remaining eight
dams, which could also pose societal and financial risk, be prioritised for future detailed investigation? To answer these questions a quantitative risk assessment approach was used. The approach utilised expert engineering and consequence panels and included input to and review of the process and outcomes by a stakeholder reference panel reporting directly to the Board of G-MW. The implementation of a strategic risk management process has now begun to progressively and systematically reduce the dam safety risk across the entire dams portfolio. This process recognises that available funding for risk reduction measures is very limited, so the highest risks are reduced in an incremental fashion to achieve interim risk targets and eventually meet contemporary dam safety standards.
Pieter van Breda, Alison White, and Greg Carmody
Site works on the $150 million Warragamba Dam Auxiliary Spillway project commenced in March 1999 and were completed in June 2002. Successful interaction with the local community, to achieve an equitable outcome, has been a feature of the communications strategy for the project.
The Auxiliary Spillway is located close to the village of Warragamba, a township of approximately 2,000 residents. The closest residence is about 200 metres from the site. The EIS and subsequent planning documents identified key localised environmental impacts that the project would impose. The main concern of local residents, including a local action group, was the impact on their amenity during construction of the Auxiliary Spillway, particularly in relation to noise, vibration, dust and traffic.
The conditions of approval for the project included a range of communication activities, of which the formation of a Community Liaison Committee (CLC) with an independent Chairperson was a key component. When the membership of the CLC was established the Sydney Catchment Authority (SCA) and chairperson agreed that it needed to fully represent the local community – and therefore included community representatives from Warragamba and two nearby villages, the Chamber of Commerce, the local action group, the local school, local council, the dam owner (SCA) and the project manager (AWT P/L).
The establishment of the CLC has proven to be very successful. It has been the voice of the community, with responsibility to act on behalf of the community and to keep them informed of progress on the project. When issues arose during the construction, the CLC were briefed on the particular matter. The CLC was instrumental in resolving these community issues and has allowed this $150 million civil project to proceed without community attributed delays.