Toronto Water Supervisory Control and Data Acquisition (SCADA) System Security: Results of the Follow-Up of Previous Audit Recommendations

Toronto Water uses this system to manage and control critical infrastructure equipment and processes used in the treatment and distribution of water. Recognizing the need to protect critical water assets, the Auditor General initiated an audit of the SCADA system in 2019 and expedited the follow-up review of the audit recommendations in 2021. The 2019 audit was the Office's first critical infrastructure audit of the City's Operational Technology (OT) systems. The objective of the 2021 follow-up review was to assess the adequacy of controls in place to address potential threats to the SCADA network, systems and applications, and to review actions taken by management since the 2019 audit. The Auditor General made 11 confidential recommendations in the 2019 SCADA audit. Given the importance of critical infrastructure systems and evolving cybersecurity threats, the Auditor General re-tested the controls to verify the implementation of recommendations. At the November 2021 Audit Committee, we provided our public report and a high-level confidential presentation on the implementation status of the recommendations. During our follow-up review, we determined that seven recommendations are fully implemented. An overview of the results is contained in Attachment 1. The details of management actions on each confidential recommendation are presented separately to this report in Confidential Attachment 1.