The wastewater treatment plant at Aarle-Rixtel is the first plant in the Netherlands equipped with a full-scale fine screen installation. At the start of the treatment process, this system removes cellulose fibres (mainly originating from toilet paper) from wastewater. Processing capacity must be increased to cope with the growing supply of wastewater. In addition, the Water Framework Directive may impose stricter requirements on effluent in the future. For this project Iv-Water has conducted a variants study based on Total Cost of Ownership, and has drawn up a design and specifications.