Scotland-based clean water technology company
RSE has opened its first North American office in the
Global Water Center, located at 247 W. Freshwater Way in Milwaukee.
Three RSE employees are currently working in the Global Water Center, which is a 98,000-square-foot building dedicated to freshwater innovations.
The Milwaukee office will allow RSE to focus on its “acquisition-focused” North American growth strategy, according to an announcement from the company.
"Whether working alone or in partnership, our tested technologies already address key challenges in the global water sector," said
Stephen Slessor, CEO of RSE. “This can be anything from rural communities in need of efficient and cost-effective treatment options, to restoring vibrancy to natural sanctuaries in the heart of large urban centers like Chicago."
RSE’s North American team will primarily focus on supplying the company’s biological and nature-based treatment technologies. This includes its modular Moving Bed Biofilm Reactors (m-MBBR), which are prefabricated units for wastewater treatment. Flexible for new sites or retrofitted treatment plants, m-MBBR can meet rural demand at lower installation and operational costs.
RSE’s strategic partnership and investment in Forres-based Biomatrix Water Solutions (Biomatrix) will also be instrumental as it deploys the company’s floating ecosystem solutions throughout the U.S. market.
Made from both recycled and natural components and described by the company as a “living laboratory," these ecosystems integrate natural processes to improve water quality and biodiversity in polluted freshwater bodies.
RSE’s American expansion follows a period of significant growth in the U.K. Launching as a startup in 1982, it now employs more than 2,000 people across 17 offices nationwide and, more recently, it has increased revenue from $71 million in 2019 to $419 million in 2025.