| PROJECTS |
Retention pond upgraded with
TERRAFORCE BLOCKS During the drought of 2017, the Cape Peninsula Universit y of Technolog y (CPUT) Bellville campus began irrigating its green spaces with recycled water from an on-site attenuation pond. The pond was subsequently found to be losing water and, in compliance with the City of Cape Town’s by-laws for stormwater management, it was upgraded and extended in August 2020. Westcoa st Ret a i n i ng Sy stem s , a Terraforce-recommended contractor, was appointed by main contractor Ruwacon to build a 420m retaining wall around the pond’s circumference using the Terraforce L12 interlocking retaining wall blocks. The project was begun by demolishing the existing inlet and outlet structures and the size and depth of the pond were extended. In add it ion to Terraforce retaining structures, gabions were built for erosion protection. New stormwater inlets were installed and a new outlet was built to control stormwater outflows. Hannes Mostert of Westcoast Retaining Systems says the blocks were installed on a
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PRECAST | ISSUE THREE | 2021
750 x 300mm, 25MPa concrete foundation, with drainpipes running behind the entire length of the wall. “All the blocks were concrete-filled for extra stability and in some places, the wall had to be built higher to protect some tree roots on the edge of the pond,” he says. With an enlarged capacity, the pond is now better equipped to deal with flooding and droughts. (Above and right): The revamped attenuation pond lined with Terraforce L12 interlocking retaining wall blocks. (Below): The new outlet.
