Reimagining dam safety management

As the owner of most of the state’s large supply dams, WaterNSW gives the highest priority to the ongoing safety of its dams to protect people, property, and the environment from the harmful effects of failure or mis-operation of its dams and reservoirs.

Delivering Operational Excellence is one of the corporate strategic priorities, given that WaterNSW is the largest bulk water supplier in Australia. This drives the business to focus on excelling in the delivery of its core operations, by being a simpler, more efficient, and responsive business to better service the needs of its customers, community, and stakeholders.

As a learning organisation, WaterNSW is constantly scanning for good practice from other dam owners across the world, as well as other major hazard industries including aircraft, railway and nuclear. The benchmarking effort has enabled the business to define its desired state in areas such as management systems and processes, technology applications, advanced analytics, and data science.

The changes to dam safety regulations in NSW provided a burning platform that has inspired the business’ transformation drive. As such, WaterNSW is driven to actively contribute to the development and implementation of leading-edge industry practice. SAFETY MANAGEMENT SYSTEM

WaterNSW has implemented some foundational elements that underpin its capability uplift in dam safety management. This includes the development and implementation of a Dam Safety Management System (DSMS) that conforms with the ISO 55001 Standard. This DSMS provides a framework for dam safety management activities, decision making and supporting processes.

DATA MANAGEMENT

At the heart of the dam safety activities is a robust surveillance program which is WaterNSW’s front line of defence for the safe operation of its dams and reservoirs. The primary objective of surveillance is to detect anomalies, and attract the attention of the responsible person in a timely manner to enable prevention measures to be taken to protect lives, property, and environment.

The key criteria for effective surveillance data, that enables engineering judgement and effective decision making regarding the safety status of the dam, are data variety, volume, and velocity. Thus, WaterNSW views data as the bedrock of a risk-informed, data-driven decision support system for dam safety.

Hence WaterNSW built DamGuard, a bespoke mobile and cloud webbased data management solution. This replaced the traditional data capturing process of using handwritten surveillance sheets to mobile capture and storage of data in real or near real-time from both manual and SCADA information.

This information is stored in a data lake. The system has automated quality assurance, provides dashboards, and alerts for rapid assessment, and includes an analytical workbench for deeper modelling analysis.

DamGuard has accelerated the data collection process and frees up Dam Safety staff to spend more time on analysis and decision making. DamGuard was awarded an iTnews Benchmark Award in 2020 in the IoT category.

SEEKING DEEPER INSIGHTS THROUGH APPLICATION OF DATA SCIENCE

WaterNSW is now looking to maximise the value of the data in DamGuard. One area of initial focus is the development of new types of

alarms which have a justifiable basis in dam safety risk, and are categorised in a way that dam safety engineers know the importance or urgency of each alarm and thus the priority with which they should act.

A Behavioural Alarm Discovery Project is underway that will identify a hierarchy of defensible alarms based on a data-scientific analysis of the historical record of surveillance data collected daily in DamGuard.

The Data Science approach will enable the extraction of knowledge from the large amounts of data through the application of advanced techniques including data mining, clustering/ classification, data modelling, machine learning and regression. In addition, a data scientific approach is expected to provide a more consistent, transparent and accurate assessment of conditions in all dams.

CAPTURING THE RIGHT DATA

In parallel with the development and implementation of DamGuard and its additional capabilities, the monitoring data to be captured must be designed or re-designed to consider potential failure modes associated with the higher levels of risk. They should be able to identify any abnormal behaviour which could lead to potential reduction of safety.

A Risk-Based Surveillance Method (RBSM) was developed and is now being applied across the portfolio to review the suitability of the current monitoring system and determine the optimum variety of critical information and instruments required. In some instances, additional instruments and sensors are needed. This is opening opportunities to adapt new technologies or modernise the system.

The RBSM evaluation has been completed at three dam sites. This has resulted in a program of works to implement a comprehensive monitoring system, including the supply and installation of new instruments, and the retrofit and upgrade of existing monitoring equipment.

The monitoring sensors are telemetry based so that monitoring data is fed back automatically to WaterNSW’s SCADA centralised data platform. The Geodetic Survey Monitoring networks at these sites have been automated. The automated survey networks have been commissioned. The benefits from the near real-time monitoring, that includes improved warning time and less site presence by staff, have been instantly realised.

EMBRACING NEW TECHNOLOGIES

Extensive new developments in dam instrumentation have emerged on the dam monitoring market. Many of these developments are spin-offs of developments in other commercially viable fields of technology. The main advantage of some of these instrumentation methods is that they can be applied or installed in existing dams with relatively limited installation work.

One example of this is the evaluation of a satellite-based Interferometric Synthetic Aperture Radar (InSAR) technique at WaterNSW. The reliability and consistency of the InSAR methods has been found to be suitable for use in the long-term monitoring of dam deformations. This is now being considered for wider application across the portfolio. EVIDENCE BASED DECISION MAKING

After all the expense and hard work of putting in place monitoring systems for a dam, then collecting data and information (including automated methods for some or all the instruments), and then storing and managing the collected data and information, the payoff comes in being able to assess the condition, performance, and behaviour of the dam accurately and confidently.

Furthermore, there is an urgent need to transition from the traditional reactive analysis to proactive evaluation using AI technologies, where an emerging threat to dam safety can be identified before it initiates, allowing more time to intervene.

In this case, the actual measured performance of dams will be compared to predicted values from Behavioural Analytical Models that are currently being developed. This promotes increased understanding of the dam in question. The effective and timely presentation of this information to dam safety engineers will enable quality insights and intelligence to be obtained that informs the safety evaluation and safety decisions.

Bill Gates said in his book, Business @ The Speed of Thought, “The most meaningful way to differentiate your company is to do an outstanding job with information. How you gather, manage, and use information will determine whether you will win or lose”. WaterNSW will continue striving to use data and information to make better safety decisions in near realtime.