Meet Principal Hydrogeologist – John Sweeney

John Sweeney

As a Principal Hydrogeologist in Tetra Tech’s groundwater team, John Sweeney provides technical advice for our clients and groundwater projects across Australia and the Asia Pacific region.

His hydrogeology expertise and project management skills are called on daily to support infrastructure and mining projects, whilst also navigating complex land contamination projects. Here, John shares insights about his work in water management solutions

Q: It is World Water Day this week, what are some of the biggest challenges professionals in your field are trying to address?

A changing climate is one of the key challenges facing all aspects of the environment. Historically, groundwater has provided a reliable alternative water supply to Australian industries and communities during periods of drought. However, in a drying climate we are expecting less groundwater to be available in coming years, which will lead to increased competition between extractive groundwater users and the ecosystems that also rely on groundwater.

Understanding how to manage these competing priorities will be one of the biggest challenges for hydrogeologists and other water experts over the next decade.

Q: As a Hydrogeologist, tell us a bit more about your area of expertise and what you focus on?

My work has increasingly focussed on assessing the potential impacts of major infrastructure or mining projects on groundwater and then working with our clients to minimise these impacts. Our team collects data from the field that we use to predict the effects that a development might have on different parts of the environment that rely on groundwater, such as wetlands, springs, rivers and areas of native vegetation.

I work with our clients and their design teams to ensure that these projects can be constructed and operated in a way that minimises impacts to other groundwater users and the ecosystems that depend on groundwater.

Q: What are some of the projects you are working on?

One of the great things about working at Tetra Tech Coffey is having the opportunity to work on a diverse range of projects that makes every day interesting. As a groundwater specialist I support a range of different projects, from tunnelling projects in Sydney, renewable energy projects across Victoria and Tasmania, and mining projects throughout the Asia Pacific region.

I’m also excited to be leading our work within the water sector in Australia. Water utilities are facing some big challenges associated with increasing water demand from a growing population, reduced water availability in a drying climate, and community pressure to manage water equitably to benefit both the ecosystems and traditional owners that have previously been overlooked. It’s great to represent our multidisciplinary teams of engineers and scientists to help address these challenges.

Q: Are we leveraging any scientific technologies or new approaches to addressing the issues?

It’s exciting to see the rapidly growing suite of digital tools that are becoming available to address old problems in new and more efficient ways.

We’re currently developing technology that uses machine learning to analyse remote sensing data to assess the health of areas of groundwater dependent native vegetation that may be at risk of impact from changes to groundwater level or quality. Innovations such as this allow us to be on the front foot so that our clients can achieve better environmental outcomes.

Q: What do you enjoy about working at Tetra Tech Coffey?

For me it’s being able to connect with and build networks with likeminded professionals. We have an impressive network of specialists across the country and globally who all love to work collaboratively to tackle challenging problems. This has obvious benefits for our clients and projects, but it has provided me with opportunities to work with and learn from some of the best scientists and engineers around the world. In 2022 I was invited to participate in Tetra Tech’s annual meeting in the USA, which brought together our leaders from across the globe. It was a great example of Tetra Tech bringing together and supporting its emerging leaders and technical experts as part of their corporate professional development program.

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