Rocla® device simplifies flow regulation in sedimentation pond

Five Rocla® Water Level Controllers are playing a key role in a program to improve the quality of Adelaide water sourced from the Mount Lofty Ranges.

The devices are being used to regulate flows in a sedimentation basin on Cox Creek in the Piccadilly Valley. The basin will remove nutrients and sediment, improving water quality in downstream watercourses and the Happy Valley reservoir.

Rocla also supplied concrete pipes and twin-cell headwalls for the sedimentation basin, as well as precast panels, 3600mm high by 1200mm wide, with cast-in bases to create a segregation wall in the centre of the pond to lengthen the flow path and improve settlement efficiency.

The pond is part of the Cox Creek Nutrient Mitigation Program, which will help decrease the cost of treating drinking water and improve water quality for aquatic ecosystems.

Cox Creek is a tributary of the Onkaparinga River, which is a major source of Adelaide’s drinking water. Although the creek has a small sub-catchment, it is responsible for a disproportionate amount of nutrients and sediments.

SA Water is collaborating with the Adelaide & Mount Lofty Ranges Natural Resources Management Board and the Environment Protection Authority to reduce pollutant loads into Happy Valley reservoir.

SA Water is delivering two major components of the program – the sedimentation pond and a wetland in the Woodhouse Scout Activity Centre.

The civil works were designed by Australian Water Environments and are being constructed by Bardavcol.

The Rocla® Water Level Controller is a simple weir system for controlling water level in upstream wetlands and ponds. The device consists of a concrete shaft with an adjustable internal weir made up of separate sections, each 150mm deep, that can be added or removed at any time to adjust the water level.

Geoff Fisher, of Australian Water Environments, said the Rocla® device provided a flexible and simple means of flow regulation, removing the need for large and complicated equipment.