12/2013 – Storm water management, Decorwall block
Storm water management with attenuation Ponds: In SA, Municipal by-laws require that storm water run-off at new property developments are channeled into attenuation ponds to prevent erosion, flooding and blocking of storm water systems.
This detention pond, opposite Zevenwacht in Kuilsriver, South Africa, captures storm water runoff from the new buildings and parking in the area, where it is stored and potentially used for irrigation. The ponds release run-off into streams and storm water drainage pipes gradually, thereby alleviating sudden rises in water levels caused by rapid storm water run-off from paved surfaces/roofs in recently urbanized areas.

The blocks’ positive up-stand locking system also sped up construction, as concrete infill was not needed.

The blocks limit the space lost around the detention pond and create the largest pond possible in the space available
An interlocking, permeable retaining wall system, the new Decorwall block system by Decorton Retaining System, was selected to limit the space lost around the detention pond and to create the largest pond possible in the space available. The blocks’ positive up-stand locking system also sped up construction, as concrete infill was not needed
Installation proved extremely difficult due to the high water table in the existing ground. Construction had to be carried out in stages to divert the water away from the working site, by drying out small areas bit by bit, a process that took place until construction was possible above water level.
Engineer: Carshif Talip of Aurecon
Main Contractor: Colin Budge of Burger and Wallace Construction
Contractor: Decorton Retaining Systems