The incident, in which a teenage female experienced an electric shock while walking along George Street, happened on 10 June 2018. Two bystanders who attempted to assist her also received shocks.

The report was commissioned by Mr Staples and was completed by experienced and independent safety investigator John Guselli. His report makes five key recommendations, all of which will be adopted.

Mr Staples apologised for the distress experienced by those directly impacted by or who witnessed the event.

“This was a highly distressing incident and I would like to apologise to the young lady and her family and all of those who were impacted by the event,” Mr Staples said.

“Safety is our number one priority and these events are totally unacceptable, which is why I commissioned the independent investigation.”

Mr Staples said the investigation examined how and why the incident occurred, the processes followed by various parties following the incident and the adequacy of the safety processes of those organisations involved.

The report concludes the incident was caused by an electric cable being compressed between the lid of a traffic signal pit and its supporting frame. The compression caused the insulation around the wire to be worn away, presenting an opportunity for the exposed wire to energise the pit lid. The report finds it is likely this situation may have existed since February 2018.

Although the last recorded access to the pit was made in February by a sub-contractor working on the light rail project, the investigation concluded it was possible another party had accessed the pit since that time.

Rain in the days before the incident created an environment which allowed the electrical current flow to energise the pit lid.

Other key findings of the report include:

Although the medical, police and maintenance responses were timely and effective, a breakdown in communications meant the serious nature of the incident and response actions taken at the scene were not known or communicated across the cluster until almost 24 hours later.

A lack of understanding of the significance of the incident influenced the response to the individuals impacted, which did not match the serious nature of the incident.

Communication between the transport cluster and the family was unsatisfactory.

Due to the complexity of site and asset ownership arrangements, there was some initial confusion about which agency had control of the site and therefore who should lead the response.

The pit is not of a standard design at 300mm deep, compared to the usual 600mm. The design of the pit is likely to have contributed to the incident.

Two suspected homeless people potentially received an electric shock at the same location a week earlier, although this was not reported at the time.

RMS traffic signalling maintenance activities could benefit from independent scrutiny.

In response to the incident the transport cluster has already taken a number of immediate safety actions, including detailed inspections of all electrical pits along George Street with no issues found.

The pit in question will be modified to conform to the typical pit design found across the rest of the city.

The recommendations focus on strengthening independent checks within RMS traffic signalling maintenance systems and consideration of extra support for safety assurance by the Secretary if required.

Safety incident escalation procedures within the transport cluster will be reviewed, ensuring that accountable managers are appointed as customer liaison and support in the event of a similar occurrence in the future, and the advice of an external expert to measure the effectiveness of any incident response exercises conducted in the future.

“While the circumstances are very unfortunate, we will learn from the incident and ensure that we do better in the future,” said Mr Staples.

“The investigation has helped to highlight areas of improvement for the transport cluster as a whole and I will make it my priority to implement the recommendations and drive the changes necessary.”

John Guselli’s investigation report is available here (PDF, 1.61 MB).