Karl Zimmerer is group managing director and cofounder of Glanua, a leading provider of water, wastewater and environmental engineering solutions across Ireland and Britain.
The company, whose headquarters is in Galway, delivers the full project life cycle, from concept, design and construction through to commissioning, operation and maintenance, helping utility, industrial and pharmaceutical-sector clients protect vital water resources and meet their environmental and sustainability goals.
Working with clients including Uisce Éireann, Thames Water, Yorkshire Water, United Utilities, and industrial companies in food and dairy, beverage, life science and pharma, and data centre sectors, Glanua describes itself as committed to delivering sustainable water infrastructure that supports communities, economic development, environmental compliance and the transition to a low-carbon future.
Describe your business model and what makes your business unique
We provide a complete end-to-end service for water, wastewater and environmental infrastructure. We design it, build it, commission it and, where required, operate and maintain it for our clients. Rather than managing multiple contractors, our clients have one partner responsible for the entire life cycle of the project.
READ MORE
Whether it’s delivering a new water supply for a data centre, upgrading a wastewater treatment plant to protect the environment or providing the infrastructure needed to support new housing development, we take responsibility for the entire solution. That’s our differentiator. Because we both build and operate infrastructure, we design with the end user in mind, creating solutions that are more efficient, more sustainable and deliver better long-term value.
What are your annual revenues and profits?
Glanua is forecasting revenues to exceed €200 million this year, representing strong year-on-year growth, supported by an order book approaching €900 million over the next few years, which provides a strong platform for sustainable growth. Today we employ more than 650 people across Ireland, Britain and Europe and have built a strong platform for future expansion.
[ Denis Brosnan-chaired Glanua back in the black following €3m reorganisationOpens in new window ]
The business has grown through a combination of organic growth and strategic acquisitions, strengthening our capabilities in operations and maintenance, bioresources and anaerobic digestion.
What is your greatest business achievement to date?
I’m proud that we’ve built a business trusted to deliver some of Ireland’s most important water infrastructure. Earning the confidence of Uisce Éireann to upgrade Leixlip and Ballymore Eustace, Ireland’s two largest water treatment plants, is something we’ve worked incredibly hard to achieve.
I’m equally proud of the people behind that success. Delivering projects like the Kerry Central regional water treatment plant, which was shortlisted for World Water Project of the Year, is only possible because of the exceptional team we’ve built. Seeing graduates who joined us in our early years now leading projects of that scale and taking on senior leadership roles within the businesses, is something I’m very proud of.
How will your market look in three years and where would you like your business to be?
The water and environmental infrastructure market will face intensifying pressure from climate change, regulatory tightening and ageing infrastructure – creating enormous opportunity for innovative specialist partners. In three years I want Glanua to be the delivery partner of choice for key clients and sectors across Ireland, the UK and, selectively, across Europe, with revenues approaching €500 million, deeper digital capability, off-site fabrication, and recognition as the sector’s most innovative engineering group.
What impact have the US tariffs had on your business? How has this affected your view of the United States as a place in which to invest?
The impact of US tariffs on our business was felt more during 2025, particularly through increased uncertainty in the market. We saw some clients postpone or defer capital investment decisions while they assessed the potential implications of tariffs and broader economic conditions.
The tariffs have not changed our view of the US as an attractive market. If anything, they have reinforced our belief that there is significant demand for innovative, flexible and sustainable infrastructure solutions. The US continues to invest heavily in water, wastewater and environmental infrastructure and we see strong alignment between those market needs and Glanua’s capabilities.
