SafeWork SA is issuing a safety alert about the hazards and risks associated with excavation work after two separate incidents have occurred resulting in workers being trapped when trenches have collapsed.


On 6 July 2021, a worker was injured after a trench collapsed while removing earth around and under existing services to allow the installation of an electrical conduit.

The worker was engulfed up to waist high by the earth for approximately 30 minutes requiring emergency services to respond. The worker received serious injuries to his spine and internal organs.

A second incident occurred on 12 July 2021 when a worker was injured after a trench collapsed while using a jack hammer.

The worker was engulfed up to shoulder height by earth for approximately 30 minutes. The worker received injuries resulting in bruising and muscle strains.

Controlling the risk

According to SafeWork SA data, 40 files have been opened since 1 July 2021 associated with incidents involving excavation work.
Of the 40 files:

  • 13 relate to exposure to open trenches
  • 4 relate to inadequate shoring of trenches
  • 3 relate to the collapse of trenches.

SafeWork SA Executive Director, Martyn Campbell said, ‘ground collapse is one of the primary risks which need to be controlled in excavation work as it can happen quickly and without warning, giving workers virtually no time to escape’.

SafeWork SA has developed new guidance information on preventing trench collapse to help manage the risks of  ground collapse, associated with excavation work.

Upcoming compliance audits

Commencing in September 2021, Inspectors will be undertaking a state wide campaign on High Risk Construction Work (HRCW)’, said Mr Campbell.

HRCW includes construction work that is carried out in or near a shaft or trench with an excavated depth greater than 1.5 metres.

The Safe work method statement compliance program 2020 audit report recommended a greater representation of civil construction to be audited.