The extraordinary structure will house a varied collection of plants originating from many countries and divided into suitable habitats. When complete early next year, the glass structure will cover 3,0002 metres and will appear to rise from the surrounding lake casting an impressive reflection in the water.

Typically, a Marley Plumbing and Drainage rainwater harvesting system works on the principle of gathering, storing and re-using rainwater which otherwise would have been wasted by flowing directly to a drainage system. In an age of floods and hosepipe bans, rainwater harvesting enables water to be reused for non potable applications such as toilet flushing and garden irrigation. 

In the case of the Wisley project Marley was called upon to design a bespoke solution to meet their exacting irrigation requirements. The system was based around a storage tank volume of 54m³ constructed from three layers of a Waterloc cells.  Two submersible pumps are housed in separate service chambers, with the inlet water from the glasshouse roof being filtered through a bank of three self cleaning filter units.

The Glasshouse will use the stored water as an irrigation source with any unused water fed back to the lake. In the event of a sudden downpour or pump failure water will overflow to the lake weir chamber and discharge to the river. 

The Bicentenary Glasshouse is split into three main planting zones: dry temperate, moist temperate and tropical climates. In addition, the facility houses a teaching garden that brings together a range of ornamental plants, fruit and vegetables to highlight plant diversity.

Marley Plumbing and Drainage’s rainwater harvesting system not only demonstrates an environmental awareness at Wisley but also provides reusable water to nurture the thousands of incredible plants that are housed beneath the glass.