Case Study
GREP — Gawler Rail
Electrification Project
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GREP electrified corridor — Adelaide rail station (2020)
Project Overview
The Gawler Rail Electrification Project (GREP) converted approximately 12 kilometres of the Gawler passenger rail line from diesel to electric traction, representing South Australia's most significant rail infrastructure upgrade in decades. Delivered by an alliance comprising ACCIONA, Lendlease, and the Department for Infrastructure and Transport, the project encompassed overhead wiring system installation, substation construction, platform modifications, structural upgrades to bridges and retaining walls, and complete signalling system renewals.
Jerome served as Construction Verifier, providing independent oversight and compliance verification across all civil, structural, rail, and electrical work packages. The verification role sat outside the Alliance delivery structure, reporting directly to DIT as the asset owner. This independence was critical for ensuring that construction outputs met design requirements, Australian Standards, and DIT's operational specifications before handover to the rail operations team.
The multi-contractor environment required managing verification interfaces across ACCIONA's civil works, Lendlease's structural packages, Siemens' signalling and electrical systems, and Tonkin's design coordination. Jerome's verification scope covered hold points, witness points, material certifications, welding inspections, concrete placement records, and as-built survey compliance across more than 40 discrete construction activities.
2021-2022 — CSR Works Interfaces & Handovers
42km Combined Services Route Coordination
On GREP I was in charge of the Combined Services Route (CSR) works interfaces and handovers across the full 42km Gawler line corridor.
- Electrical and communication conduits + pits installed by multiple subcontractors along 42km of rail corridor
- Interfaces managed across multiple road intersections, bridges, and train stations
- Coordinated handovers to SIEMENS for cable installation, connection and commissioning to switchboards and rail track equipment per their design
- Independent verification across civil, structural, rail, and electrical works to confirm design requirement compliance
Scope of Work
JCY delivered independent construction verification services encompassing:
- Design requirement compliance verification across civil, structural, rail, and electrical disciplines
- Hold point and witness point inspections per approved inspection and test plans (ITPs)
- Multi-contractor interface management between ACCIONA, Lendlease, Siemens, and Tonkin
- Construction quality auditing against project-specific quality management plans
- Review of material certifications, concrete batch records, and steel mill certificates
- Welding inspection coordination and verification of NDT results for structural steel connections
- As-built survey compliance verification for track geometry, platform levels, and overhead wiring clearances
- Non-conformance report (NCR) tracking, assessment, and close-out verification
- Verification reporting to DIT on construction progress, quality trends, and risk areas
- Pre-commissioning checks and verification sign-off for energisation and operational handover
Key Challenges & Solutions
Multi-Discipline Coordination
The GREP Alliance involved civil earthworks, structural concrete and steel, overhead wiring, signalling, and track works occurring simultaneously across multiple sites. Verification activities had to span every discipline without creating bottlenecks. Jerome implemented a risk-based verification programme that allocated inspection intensity by criticality: full hold-point verification for safety-critical elements such as overhead wiring clearances and structural connections, with statistical sampling for lower-risk repetitive works like cable tray installations.
Live Rail Environment
Significant portions of the work occurred within the existing rail corridor during operational hours, with construction windows limited to weekend possession periods. Verification inspections had to be completed within the same compressed possession windows as construction activities. Jerome pre-staged verification documentation and checklist packages before each possession, enabling rapid on-site sign-off and reducing the risk of possession overruns that would impact Monday morning passenger services.
Independent Reporting Integrity
Maintaining genuine independence within an alliance delivery model required clear separation between the verifier role and the delivery team's commercial and programme pressures. Jerome established structured reporting pathways directly to DIT's project director, with transparent NCR escalation protocols that ensured non-conformances were documented and resolved regardless of programme impact. This approach identified three critical structural detailing issues that were rectified before they reached operational service.
Technical Details
Verification Scope
- Overhead wiring system clearance verification
- Substation structural and electrical commissioning checks
- Platform modification compliance (DDA and operational requirements)
- Bridge strengthening and retaining wall verification
- Signalling cable routing and termination inspections
Deliverables
- Verification compliance reports per construction activity
- NCR register with root cause analysis and close-out tracking
- Risk-based inspection programme documentation
- Pre-commissioning verification sign-off packages
- Monthly verification status reports to DIT project director
Project Partners
Project Gallery
On-the-ground photography from this project.
Need a Similar Capability on Your Next Project?
JCY provides independent construction verification for rail, road, and infrastructure projects where quality assurance and design compliance are non-negotiable.