Delivering safe water at scale: SCADA and PLC modernisation

Opportunity

The Australian Drinking Water Guidelines (ADWG) require Critical Control Points (CCPs) within water supply schemes to be closely monitored to ensure the delivery of safe drinking water. These CCPs include treatment processes such as chlorination, UV disinfection, filtration, and reverse osmosis. In Western Australia, Water Corporation is responsible for monitoring these processes and reporting performance against critical ranges as directed by the Department of Health.

To strengthen compliance and improve operational reliability, Water Corporation initiated a program to upgrade chlorination control systems at critical water treatment sites across Western Australia.

SAGE Automation was engaged to upgrade 55 water treatment plants to the latest Chlorination Version 5 PLC code and SCADA standards. The project involved modernising legacy treatment plant control systems, aligning them with current Water Corporation standards, and improving monitoring capabilities for key treatment processes.

The scope included both partial upgrades, where existing control code was modified to meet the new standards, and full upgrades, where systems were completely upgraded to the Water Corporation Chlorination V05 standard.

Solution

Delivering this many upgrades across the state needed a well‑coordinated approach, as there were a number of technical and logistical challenges.

Maintaining a continuous water supply during system cutovers

Because these assets supply drinking water to populated areas and towns, shutdown windows were extremely limited. This required detailed planning, risk management strategies, and clearly defined rollback procedures to ensure uninterrupted water services.

Challenges presented in the project:   

• Limited shutdown windows to avoid disruption to the drinking water supply

• Integration with existing infrastructure and legacy control systems
• Coordinating engineering resources and commissioning activities across multiple regional locations
• Ensuring compliance with Water Corporation standards and the Australian Drinking Water Guidelines. 

As a member of Water Corporation’s Operational Technology Panel, SAGE brought extensive experience with the organisation’s control systems, standards, and operational environment.  

Successful delivery required: 

• Close collaboration with Water Corporation project teams and regional stakeholders

• Detailed planning of cutover and commissioning activities to maintain a continuous water supply

• Alignment with Water Corporation’s electrical and SCADA design standards

• Local Western Australian engineering team experienced in water sector delivery

• Dedicated technical leadership overseeing design and control systems engineering teams.  

To support the delivery, SAGE also partnered with MEEC (for all electrical installations) and West Water for the installation of inlet and outlet flow meters and chlorine vacuum manifold pressure transmitters. 

All modernisation work was delivered by the SAGE Automation Perth Engineering and Project Delivery team, efficiently coordinated across the state. 

The scope of delivery included:

• PLC and SCADA software development  

• Electrical and control system design documentation

• Factory acceptance testing of control systems

• Detailed Commissioning and Cut-Over Planning  

• On-site commissioning and validation

• Full project management including scheduling, subcontractor coordination, Stakeholder management and Risk Management.

Outcome

SAGE successfully upgraded 55 critical water treatment sites across Western Australia, delivering improved monitoring and reliability of chlorination systems.

The upgrades enable Water Corporation to maintain accurate monitoring of critical control points and ensure compliance with the Australian Drinking Water Guidelines.

Most importantly, all system upgrades were completed without interruption to the water supply, supporting Water Corporation's ongoing delivery of safe drinking water to communities across Western Australia throughout the project. 

Project highlights

• 55 water treatment sites successfully upgraded

• Alignment with the latest Version 5 PLC chlorination standards

• Enhanced monitoring of critical control points

• No lost-time injuries recorded

• No disruption to the water supply during any site cutover

• No water quality incidents related to the scope of works. 

Water Corporation now benefits from modern control systems and hardware that support long-term operational reliability and improved monitoring capabilities.