Sewaco has developed a range of open and closed top rectangular and polytower structures suitable for containment of modular plastic media. The design of each containment shell ensures adequate ventilation of the media pack. Shells can be single skin internally clad or double skin externally clad with an internal impervious membrane for maximum protection of the structural elements. A wide choice of finished colours is available to meet local planning requirements. All structures are formed from materials that are aesthetically pleasing and suitable for recycling at the end of their operational life.