Waste Treatment Plant Koolong

Fulton Hogan were awarded the contract for the upgrade of the waste water treatment 
plant at Koorlong near Mildura by Lower Murray Water. The existing process at the WWTP comprises a chemically assisted sedimentation process 
(CAS) before irrigation of on-site tree lots with primary effluent. The existing plant has a 
design Average Dry Weather Flow (ADWF) capacity of 3.3 ML/day. The WWTP will treat 
after the upgrade an average dry weather flow of 11.85 ML/d. The peak wet weather flow 
for treatment is 400 L/s.

The upgrade includes:

• Supply and install new D450 influent electromagnetic flow meter and associated pit.
• Construct new inlet works including Receival chamber, automatic band screen, automatic 
screen bypass channel with coarse screen, screenings washpactor and vortex-style grit 
removal.
• Construct 4 sequencing batch reactors (SBR) with integral flow splitter.
• Supply and install end pivot type decanters for the SBRs.
• Design and construct diffused air aeration system complete with blowers and necessary controls.
• Construct new decant balance tank.
• Design and construct a new channel style low pressure UV disinfection system.
• Construct new magnesium hydroxide liquid (MHL) storage and dosing system.
• Construct new phosphoric acid storage and dosing system.
• Gertzel Engineering Surveyors are supplying all surveying services for the upgrade.