98% of the water can be safely discharged overboard
For over 37 years, Qua-vac has been supplying wastewater treatment systems to shipping company Scylla for their river cruise ships—whether for brand-new vessels or for refurbishments of existing ones, also known as refits.
The Scylla fleet now consists of 43 ships that excel in technology, design, and quality. Since May 2025, the MS Riviera Radiance has been part of this fleet—a stunning hotel cruiser built for the Rhine and Danube rivers. The Riviera Radiance accommodates 182 guests, featuring 4 luxurious suites, 8 elegant junior suites, and 79 comfortable double cabins. The spacious cabins with large windows create a comfortable atmosphere and ensure an unforgettable river cruise experience.
Sustainable wastewater treatment
We’re proud to have contributed to the Riviera Radiance. In collaboration with our long term-partner Klimaatservice Holland, we installed an sustainable wastewater treatment system from the Evac portfolio. This includes the Evac MBR (Membrane BioReactor), quiet and water-saving vacuum toilets, and a compact grease separator for the bistro—all designed to treat wastewater efficiently and in an eco friendly way.
MBR Installation
The MBR is an advanced biological system that purifies wastewater (suitable for any type of vessel, from yachts to cruise ships)—including black water from toilets and grey water from showers, sinks, and washing machines. Even kitchen wastewater is treated, thanks to the installed grease separator. All wastewater is purified without the need for further post-treatment.
We also supplied Evac Optima 5 vacuum toilets—quiet vacuum toilets that use very little water (just 0.5 to 1.2 liters per flush). For the bistro, we provided a compact grease separator to ensure efficient and eco-friendly operations there as well. All products are specially designed for the maritime sector, easy to use and maintain, and built with sustainability in mind.
Modular System
The system is modular, with the vacuum tank and mixing tank separated from the MBR tank. In collaboration with Klimaatservice Holland, we ensure that the tanks are installed efficiently and in a space-saving manner within the vessel’s hull. The necessary flanges for the fittings are welded directly onto the tanks, allowing for easier installation and eliminating the need for further processing of the stainless steel tanks. Nearly all water can be safely discharged overboard
The MBR naturally purifies wastewater through membrane filtration. The result? Water of such high quality that 98% of the treated water can be safely discharged overboard—fully compliant with the strict Rhine navigation regulations and MEPC.227(64) standards.
Together with Klimaatservice Holland, we are committed to providing custom solutions and dedicated service to ensure every Scylla river cruiser is not only comfortable but also cleaner, greener, and more sustainable.
