A new tool for sustainable water infrastructure in New Zealand

AECOM has partnered with Christchurch City Council (CCC) in New Zealand to create the 3 Waters Emissions Estimation Tool (3WEET), a user-friendly tool that enables the estimation of emissions associated with the design and construction of water assets.

Working with clients like CCC, AECOM has led the development of various tools like 3WEET by understanding industry needs, fostering interdisciplinary collaboration, engaging stakeholders, conducting New Zealand-specific research, and working closely with users to apply the tool's results.

3WEET has been specifically developed for the delivery of three waters projects to support CCC's commitment to carbon neutrality by 2045 and assists in efficiently reporting against the metrics and targets as part of the recommended Taskforce on Climate-related Financial Disclosures (TCFD) framework.

With a focus on water infrastructure renewals, 3WEET incorporates local details and data to provide project-specific outputs that highlight the primary emissions contributors.

Once fully developed, 3WEET will be made available online for anyone to use at no cost to allow consistent decision-making across three waters projects in New Zealand.

**Measuring and reporting on greenhouse gas emissions **

In response to the increasingly evident impacts of climate change, it has become crucial to measure greenhouse gas emissions throughout the entire lifecycle of a project. 3WEET facilitates this process, measuring and reporting on a project's emissions broken down by scopes: material manufacture, transportation to the site, installation, and ongoing impacts such as energy loss due to pipe friction. The tool also takes into account any carbon sequestration resulting from planted areas within the project.

3WEET offers an initial estimate or benchmark of carbon emissions, providing an opportunity to explore alternatives that minimise project emissions. Users can conduct design case comparisons to quantify the impact of different installation methodologies and materials, as well as compare nature-based solutions with traditional piped networks.

As the project progresses from design to construction and material procurement, 3WEET enables the comparison of emissions from different suppliers and their products by incorporating third-party verified Environmental Product Declarations (EPDs). In response to CCC's request, the tool will also include the capability to generate cost estimates, assisting with the automatic generation of a schedule of quantities with sufficient information for cost estimators.