Chestle Pill Outfall Design

There are a number of existing outfalls throughout the ASEA project area. We need to raise the height of the outfalls, in-line with the new flood defences. In many cases, in order to support the increased height, we need to widen the outfalls, to support the extra load.

At Chestle Pill Outfall, the existing outfall structure would not have supported the additional load from the increased height. To overcome this, we looked at ways of reducing the weight of the existing earth over the outfall. We identified the best way to do this was to replace some of the existing earth over the structure with lightweight high strength modular cells. This network of cells has a 95% void ratio – being much lighter in weight than the ground they will replace but still robust enough to support the same load. It is also recyclable at the end of its service life.