Global climate change will amplify existing risks, as well as create new risks for natural and human systems. Recent climate changes have already had widespread impacts on human and natural systems. Dams provide a range of economic, environmental and social benefits including irrigation, flood control, water supply, hydroelectric power, recreation and wildlife habitat and play an important role in human settlement. Adapting into the effects of climate change is vitally important for future management of dams. This paper uses the recent drought and floods in Victoria to illustrate the importance of considering the effects of climate change in design, operations, maintenance and emergency management of dams.
Now showing 1-12 of 59 2982:
While structures such as a dam walls, pipelines, gas storage tanks, and nuclear facilities are vulnerable to the shaking from earthquakes, they are even more susceptible to differential movement on faults passing beneath their foundations.
In the past, the probability of surface rupture of a fault was calculated by making some simplistic assumptions about the distribution of earthquake magnitudes. Improved databases of earthquake ground faulting now allow the probability of surface rupture to be estimated in a more realistic fashion. Computing software that uses a Monte Carlo approach has been developed to allow the effect of various scenario choices on rupture probability to be investigated.
Using this software, it is found that the most significant influence on rupture probability is the long-term fault slip-rate. Other assumptions about the faulting style, maximum magnitude and conversion parameters have only a moderate influence on the results.
There have been several instances in recent history in Australia of surface faulting due to earthquakes, but there has been only limited damage to infrastructure due to the remoteness of these earthquakes. The software that has been developed will allow a considered assessment and comparison of the hazard and risk due to both ground shaking from earthquakes and from surface rupture.
The As Low As Reasonably Practicable (ALARP) principle was established in the Australian Dams
community in the ANCOLD Guidelines on Risk Assessment in 1994. Since that time, dam owners have been focused on reducing their societal risk to below the ANCOLD Limit of Tolerability (LoT) through dam safety upgrades and are now considering how to justify an ALARP position. This paper presents a framework that provides a systematic approach to assembling the inputs, applying a process and documenting the outcomes of an ALARP assessment. It is a pragmatic approach that aligns with the safety case, which is a legislated requirement for Major Hazard Facilities in Victoria.
The framework has been applied to two dams in Melbourne Water’s portfolio with differing societal risk, size, uses and criticality to the water supply system. It has highlighted the importance of dam safety governance, documentation of procedures, defensible technical analysis and an ongoing engagement with leading industry practice, in demonstrating risks are ALARP.
On 1 July 2017, the Water Supply (Safety and Reliability) Act 2008 (Qld) was amended to improve the way referable dam owners manage dam safety and integration of dam safety with disaster management. While each dam and emergency event differs, and each state has different dam safety and disaster management legislation, it is important that communication strategies are effectively delivered to empower dam owners and emergency practitioners to improve warning capability for affected communities. The paper provides an overview of the intent of the amended legislation, key concepts, what makes an effective emergency action plan and a performance analysis of the emergency action planning regulatory program. Lessons learnt from the analysis are provided.
This paper will explore the differences in pore pressures resulting from saturated and unsaturated seepage (pore pressure) analysis. It will also evaluate some conventional recommendations, such as the inclusion of essential components of the embankment dam and omission of inessential components. In addition, the identification of inessential components will be discussed.
Finally, pore pressures obtained from these analyses will be compared to monitoring data in order to identify the most appropriate seepage (pore pressure) model.
In conclusion, advantages and disadvantages of each method will be discussed and recommendations will be provided in order to gain the most appropriate results.
The results of this paper can be used for designing new embankment dams or safety reviews of existing dams, particularly when there is lack of reliable monitoring data.
New technology and outputs from flood forecasting systems can raise issues for dam safety managers in how they use uncertain information to make critical dam safety decisions. In particular, making operational decisions around pre-releases based on forecast inflow presents challenges. In this case dam safety risk needs to be weighed up with other risks such as increasing downstream flooding, or being able to supply water into the future. The process of developing a flood forecasting system should be a close collaboration between the developers and the users. This ensures that outputs provide meaningful information that can be used to support operational decision-making in a flood or emergency response situation.