Sustainability

Reducing our carbon footprint, avoiding waste and leaving a positive social and cultural legacy for Tāmaki Makaurau are the key elements of City Rail Link’s aims for sustainability excellence. These aims inform all aspects of the project, from design, through construction and operation.

The project's sustainability performance is externally verified with the ISC, using their Infrastructure Sustainability rating tool, which has been adapted in partnership with mana whenua to respond to Aotearoa's unique cultural context.

In 2022, Link Alliance submitted an application with ISC for a Design rating verification of the main contract (C3), including the tunnel, three stations and western line connections. CRL Ltd was awarded a 'Leading' As Built rating - the highest rating achievable - for C1 works at Waitematā Station (Britomart) at the lower end of Queen Street. The C1 rating recognised the hard work and commitment of C1 contractor Downer Soletanche Bachy Joint Venture.

CRL Ltd’s Sustainability Strategy has five key focus areas:

• Reducing resource consumption

• Zero waste to landfill

• Social outcomes

• Mana whenua outcomes

• Governance and reporting.

A summary of progress across each of these areas is provided, using examples to illustrate how the project is working to create a new paradigm for delivering infrastructure sustainably.

Reducing resource consumption: energy, materials and water

Building the CRL comes with a significant up-front carbon 'cost', both in energy-related greenhouse gas (GHG) emissions and the embodied carbon of the materials used during construction. Water is also required, both during construction and operation of the CRL.

The project aims to use the least amount of resources possible during construction and over the infrastructure's 100-year lifespan through efficient design and construction methodologies.

To track the project's success, an estimate called a Base Case has been created for each construction package. This measures the total amount of energy, materials and water that would be used to build and operate the CRL if business-as-usual occurred without sustainability interventions.

A Detailed Design, which includes initiatives to reduce resource consumption, is then developed. Comparison between the Detailed Design and the Base Case then enables the project to quantify improvements in resource use.

Contract 1 (C1) and Contract 2 (C2) have been completed with significant savings achieved and Contract 3 (C3) is on track for significant resource savings.

• C1 was awarded an Infrastructure Sustainability 'Leading' As Built rating – the highest possible.

• C2 was awarded an Infrastructure Sustainability 'Excellent' As Built rating.

Construction is well underway for C3 where the Link Alliance sustainability team have finalised Base Cases and Detailed Designs for each element, with an Infrastructure Sustainability 'Leading' Design rating currently being verified. Link Alliance continues to identify, implement, and measure progress to minimise resource use.