HDS Australia has recently designed and project managed the construction of the Community Wastewater Management System for the town of Mallala. Prior to 2014, the town sanitation was poor with a high percentage of ageing or failed septic tanks and very limited re-use of variable quality water, resulting in a public health risk and wasted resource.
The new system was designed by HDS Australia and includes wastewater collection by gravity drain, transfer by rising main to a biological wastewater treatment plant and return of the treated water for controlled re-use in the town’s recreation areas, including the community oval.
The infrastructure includes 6.5km of gravity drain serving 320 connections, 5km of directionally drilled rising mains and irrigation mains and a 12ML storage pond. The wastewater treatment plant, with a capacity of 180kL per day, consists of biological treatment with tertiary disinfection to achieve the desired re-use quality at minimum operational and maintenance cost.
The two main contractors, SADB for the civil works and EWS for the treatment plant, were managed by HDS Australia as Project Superintendent. Property connections to the new system will commence in April 2015, approximately 14 months after project start-up.