Excavation & Trenching SWMS

Trench collapse kills faster than almost any other construction hazard — a cubic metre of soil weighs over one tonne and burial beyond chest depth is usually fatal within minutes. The WHS Regulation 2025 classifies work in or near a trench deeper than 1.5 metres as high risk construction work requiring a SWMS. This template covers excavation planning, underground service identification, ground support systems, and exclusion zone management mapped to the binding Excavation Work Code of Practice effective 1 July 2026.

Legal Requirements

regulation

WHS Regulation 2025 Part 4.4 — High Risk Construction Work

hrcw category

Work in or near a trench deeper than 1.5 metres

code of practice

Excavation Work (binding 1 July 2026 under Section 26A)

section 26a binding

Yes — effective 1 July 2026. Non-compliance is admissible as evidence of breach.

hrwl required

Not specifically required but EWP/crane licences may apply for associated plant

Hazards

Hazard	Consequence	Likelihood
Trench wall collapse or cave-in	Death by crushing or suffocation	Likely
Underground service strike — gas, electrical, water, comms	Electrocution, explosion, flooding	Possible
Groundwater ingress and flooding	Drowning, trench wall destabilisation	Possible
Mobile plant operating near trench edge	Edge collapse, worker crush	Possible
Worker struck by excavated material or spoil pile collapse	Fractures, burial	Possible
Exposure to contaminated soil or ground gases	Chemical burns, respiratory illness, asphyxiation	Unlikely

Controls (Hierarchy of Controls)

Eliminate the need for workers to enter trenches by using trenchless construction methods where feasible

Obtain Dial Before You Dig (DBYD) plans and verify service locations with non-destructive methods before breaking ground

Install shoring, trench shields, or benching/battering systems for all trenches exceeding 1.5 metres depth

Establish exclusion zones preventing mobile plant from operating within the zone of influence of the trench wall

Install dewatering systems and monitor groundwater levels continuously during excavation

Maintain spoil piles at least 1 metre from trench edges

Provide safe means of entry and exit — ladders within 9 metres travel distance

Conduct geotechnical assessment for excavations exceeding 3 metres or in unstable ground conditions

Recent Prosecutions

Rahme Civil Pty Ltd$400,000 + $50,000 costs

Unsupported trench wall collapsed onto worker. No shoring installed despite depth exceeding 1.5 metres and unstable clay soil. Worker suffered crush injuries.

2024 — SafeWork NSW v Rahme Civil Pty Ltd [2024]

Keks Projects Pty Ltd$180,000

Workers entered deep excavation with no edge protection, no safe access/egress, and no shoring. Multiple workers exposed to collapse risk.

2024 — SafeWork NSW v Keks Projects Pty Ltd [2024]

What Your SWMS Must Include

✓Geotechnical assessment or competent person soil classification for excavations exceeding 1.5 metres

✓DBYD service location plans and non-destructive verification records

✓Ground support system design — shoring, battering, or benching specifications

✓Exclusion zone distances for mobile plant relative to trench depth

✓Emergency rescue procedure for trench collapse including contact details for rescue services

Need a compliant Excavation SWMS?

Our WHS consultants develop site-specific excavation SWMS with geotechnical input and ground support specifications that satisfy regulator expectations.