Northern Transmission Project

We lead the development and implementation of the project’s environmental approvals strategy, coordinating the South Australian impact assessment process with Commonwealth environmental assessment requirements.

This includes defining the scope and sequencing of approvals activities, identifying information requirements and establishing the relationship between statutory assessment, technical investigations and design development.

Our role has included establishing approvals strategies, developing placeholder Assessment Requirements to guide investigations while statutory requirements are being prepared by DHUD, coordinating environmental referrals and assessment documentation, and managing multidisciplinary technical studies. This approach maintains programme momentum, with study scopes reviewed against statutory requirements once issued.

By establishing these requirements early, we help the project team understand the work needed to progress assessment, anticipate dependencies and incorporate approvals activities into the wider project programme.

We developed the constraints mapping and corridor identification assessment for the Northern Transmission Project. Our work established a structured methodology for identifying potential transmission corridors across a broad study area.
The assessment combined desktop research, government spatial datasets, regional planning information, aerial photography, site observations and multidisciplinary project workshops. We classified constraints into two tiers according to their environmental sensitivity, safety implications, approval complexity and potential effects on engineering and construction.

Tier 1 constraints: avoid as far as practicable

We identified and mapped constraints requiring the highest priority for avoidance, including:

• High-risk Commonwealth land, including sensitive defence and national security facilities.
• Ramsar wetlands.
• Airports and airstrips.
• Waterbody and gully crossings requiring transmission spans greater than 800 metres.
• Slopes of 30 degrees or greater.
• High bushfire risk zones.
• Existing or approved energy generation and storage development footprints.

Tier 2 constraints: minimise interactions and impacts

We also identified and mapped constraints requiring impact minimisation and further consideration during corridor development. These included:

• Threatened ecological communities, protected flora and fauna, native vegetation, conservation areas and nationally important wetlands.
• Vegetation heritage agreements, environmental offset sites and significant roadside and railside areas.
• Registered Aboriginal heritage sites and listed non-Aboriginal heritage.
• Productive and sensitive land uses, residential and farm infrastructure, townships, tourism assets and recreation trails.
• Landscape protection areas, character preservation districts and land management agreements.

We established an approximately one-kilometre hexagonal GIS grid across the study area to organise and analyse constraints consistently. Cells intersecting Tier 1 constraints were flagged, while Tier 2 features were counted within each cell to map the concentration of overlapping constraints.

We separately mapped opportunities, including existing transmission easements and infrastructure corridors identified through regional planning. These layers were overlaid with the constraints mapping to examine potential pathways and opportunities to utilise existing infrastructure or disturbance.

Using this spatial analysis, aerial photography, technical knowledge and field observations, we identified and refined potential corridors. We assessed their interactions with Tier 1 and Tier 2 constraints, alignment with mapped opportunities and estimated length. Constraint measures were normalised by corridor area to allow comparison between options of different widths.

We documented the methodology, data sources, assumptions, comparative analysis and limitations into a Corridor Identification Report, including requirements for incorporating further stakeholder input and specialist investigations.

We developed the multi-criteria analysis methodology and delivered the project’s MCA Outcomes Report. Our work combined spatial evidence, technical information and stakeholder priorities within a structured framework for comparing transmission corridor options.

The methodology incorporated quantitative measures and qualitative judgement, supported by documented criteria, regional weightings, scoring procedures and sensitivity testing.

We structured the assessment around three regions: Greater Adelaide, Mid North, and Upper Spencer Gulf and Flinders. Each region had its own weighting process to reflect local priorities and circumstances.

The workshop programme involved representatives from 33 organisations, including councils, landscape boards, regional development organisations, community associations, tourism and heritage groups, conservation organisations, agriculture and industry.

We incorporated stakeholder input into the assessment criteria, performance measures, regional weightings and corridor scoring. Supporting material included maps, quantitative information and photographs, supplemented by discussion with project specialists.

We structured the MCA around 15 sub-criteria grouped under five themes:

• Environment and land: biophysical environment, surface water, greenhouse gas emissions and land use.
• Social sustainability: Aboriginal heritage, tourism and non-Aboriginal heritage, business and economic effects, health and amenity.
• Technical performance: engineering constructability, operation and maintenance.
• Strategic fit: renewable energy transition, network connection capacity, and security and reliability of supply.
• Cost: whole-of-life cost.

Corridor options were assessed on a five-point scale against the agreed criteria. The process incorporated anonymous stakeholder scoring, with median scores used as the primary basis for analysis to reduce the influence of outlying responses.

We compiled and analysed the scoring data, applied regional weightings and documented the assumptions and evidence supporting the assessment.

We undertook sensitivity analysis across 16 alternative weighting scenarios. These included increasing the emphasis on individual themes, removing themes, assigning full weighting to a single theme and testing an equal balance between strategic fit and cost.

We also compared median and mean scoring methods and examined the influence of different regional weighting sets on corridor performance.

Our reporting documented the assessment framework, stakeholder participation, scoring methodology, sensitivity testing and data limitations. We identified where further investigation, technical assessment and stakeholder engagement would be required as corridor planning progressed.

We manage the environmental regulator interface, coordinating discussions on approval pathways, assessment scope, technical requirements and the information needed to support statutory decision-making.

This includes preparing for regulatory discussions, bringing relevant specialists into the process and coordinating responses to questions and feedback. We help translate regulatory expectations into clear actions for consultants and the wider project team.

Through this engagement, we identify issues requiring early resolution and maintain alignment between the assessment programme and the requirements of the relevant authorities.

We also support project leadership with advice on regulatory risk, assessment dependencies and the implications of changes to project scope or timing.

We work with ElectraNet’s engagement and land teams to ensure environmental assessment and consultation inform one another.

Our role includes supporting public consultation, explaining environmental constraints and assessment processes, and helping technical teams respond to issues raised by communities and stakeholders.

We coordinate the consideration of feedback within corridor investigations and technical assessment scopes. This helps ensure that relevant concerns are carried into the work needed to assess alternatives, refine the project and develop mitigation measures.

We develop technical scopes and procurement requirements for approvals consultants and specialist investigations, helping ElectraNet secure support suited to the project’s complexity and programme.Our contribution includes defining work packages,

larifying deliverables and interfaces, and supporting the evaluation and management of consultant inputs. We coordinate technical reviews and data quality checks so that information can be used consistently across assessment, design and project reporting.

We also help manage programme, budget and consultant dependencies within the environmental workstream, providing project leadership with visibility of emerging issues and the actions needed to address them.

We work with engineering and project teams to translate environmental constraints and assessment findings into practical design considerations.

This includes informing corridor refinement, identifying areas requiring further investigation and incorporating environmental requirements into technical scopes and contract documentation.

Our approach considers how commitments made during assessment will be implemented later. By connecting proposed mitigation with design, procurement and delivery responsibilities, we help establish a practical foundation for future environmental management and compliance.

We support the development of sustainability management plans and assessment scopes aligned with Infrastructure Sustainability Council principles and project objectives.

Our focus is on identifying relevant sustainability provisions early and incorporating them into technical investigations, design inputs and procurement requirements. This allows information collected for environmental assessment to also support sustainability planning and future evidence requirements.

The approach helps identify opportunities, clarify responsibilities and reduce the need to revisit completed studies as sustainability requirements develop.

Our contribution extends across strategy, technical assessment, regulatory coordination and project governance.

We provide a consistent environmental interface between ElectraNet’s leadership, specialist consultants, engineering teams and engagement functions. This helps connect decisions across disciplines and gives the project team clear advice on environmental risks, information needs and approval dependencies.

Through this integrated role, we are helping establish the evidence, processes and responsibilities needed to progress a complex transmission project through assessment and towards delivery.