We maintain the highest safety standards while focusing on quality workmanship and timely delivery.

Bunbury wastewater treatment plant upgrade

Works were required at Bunbury WWTP to increase the treatment capacity to a value of 13ML/D to cater for the WWTP inflows. GO was selected as head contractor to carry out works including a dewatering upgrade with gravity drainage deck building, sludge treatment upgrading, dewatering centrifuge, polymer storage, a batching and dosing system and the aeration and sequencing batch reactor upgrade. New LV switchboards, a LV switchroom and blower room building with tilt-up panels, a process air upgrade, reuse filtrations system, HV power supply and electrical instrumentation and SCADA systems were all installed during the project.

Hahndorf wastewater treatment plant Inlet works

GO delivered this ECI project for the concept design, design reports and construction costing followed by an AS4300 Design and Construct contract. With tie-ins to the existing plant, GO built a new inlet chamber – raised to improve hydraulics, inlet fine screens with a coarse screen bypass channel and incorporated a grit removal system, screenings and grit handling equipment. A flow splitter box with flow measurement and control was installed, along with a Return Activated Sludge pumping station with mechanical ventilation for corrosion prevention and foul air management. Operational impact was minimised by constructing a unique temporary concrete chamber within the oxidation ditch, allowing new isolation valves to be installed without interrupting plant flows.

Bird in Hand wastewater

GO was a 50% shareholder in the GOLD Joint Venture to deliver the Bird in Hand Wastewater Treatment Plant for SA Water.

The project was delivered through Early Contractor Involvement (ECI) followed by a fixed lump sum contract for the Design and Construction of the 12.5 ML/day Wastewater Treatment Plant and Reuse Pipeline. GO personnel took responsibility for design management as well as the detailed design and construction of all buildings mechanical and electrical works, which included:

  • Buildings for blowers, chemical dosing, sludge handling, switchboards and amenities
  • Inlet works incorporating inlet screens, and grit vortex system
  • Two activated sludge reactors, aeration systems and clarifiers
  • RAS, WAS and Reuse pumping stations
  • Tertiary treatment facilities incorporating Disc Filtration and UV Disinfection
  • Sludge facilities including thickener, centrifuge and digester with energy recovery
  • Chemical storage and dosing facilities
  • HV power supply including new transformer
  • Switchboards and SCADA control systems
  • Testing and Commissioning

This was SA Waters' first ECI project and construction was completed six months ahead of schedule while keeping the existing plant operational throughout. The team added value by offering a sludge digester in lieu of lagoons, providing a technically superior solution within the original budget and avoiding the need for a flare stack.

Glenelg wastewater treatment plant sedimentation tank refurbishment

The sedimentation tanks and mechanical equipment at the Glenelg WWTP were severely deteriorated, and the objective of this project was to rehabilitate them to ensure ongoing serviceability and reliability. The work involved condition assessments, 400m2 of concrete remediation, 2500m2 of concrete protective coating and replacement of sludge scraper chain systems. The quantity of concrete repair required almost doubled during the project and new concrete repair products and methods allowed the work to be completed on schedule with a higher quality finish. The client also congratulated GO on the excellent collaboration with other contractors on site.

“The installation in Tank 4&5 was amongst the best I have ever seen in 25+ years of involvement with the Polychem product.” 
Nigel Ayres  supplier of the scraper system

Denmark wastewater treatment plant upgrade

This was a detailed design and construct contract for a 1.20ML/day upgrade of Water Corporations Denmark WWTP in southern WA. Work consisted of new inlet works, incorporating fine screens and grit removal, 1.2MLD oxidation ditch with surface aerators and submersible mixer, a tanker receival pump station, odour collection and treatment facilities, chemical dosing facilities for Alum, Magnesium Hydroxide, Polymer and Hypochlorite and an operations building to accommodate electrical, control and SCADA systems. The construction program was challenged by high rainfall, design changes to the oxidation ditch and an unidentified HV cable running through the site. Despite this the project was completed on schedule and is consistently producing water to specification.

Christies Beach sludge dewatering plant, odour control plant & HV power supply

The Christies Beach WWTP Upgrade Project involved GO delivering one of the critical packages; a new HV power supply for the site as well as dewatering and odour control facilities. Work also included screening of primary sludge using a rotary strain press, sludge transfer, storage and loading conveyor systems, Polymer Dosing Systems and odour control plant including Chemical Scrubber and Activated Carbon Scrubbers. Close communication with both the client and plant operators allowed this project to be completed safely under an accelerated construction schedule.

Rottnest Island wastewater treatment plant upgrade

This project for the Rottnest Island Authority required the conversion of an existing aerobic digester into a Membrane Bioreactor (MBR) plant. GO's contract was for the design and construction of earthworks, process building including a control room, biological reactor and aeration systems, ultra-filtration membrane filters, chemical dosing and UV disinfection systems, pumping systems, electrical and control systems. The site is on an island off the coast of Perth, so construction required meticulous planning for the transport of equipment and the management of construction resources. The client subsequently awarded GO contracts for other work on the island unrelated to the treatment plant.

Gordon Rd WWTP & Halls Head WWTP Inlet Works

This project involved the design and construction of new inlet works at two of Water Corporations wastewater treatment plants near Mandurah, WA. Both sites included new inlet screening channels in a duty/standby arrangement containing Centre-flow band screens. Miniwashers were installed below the band screens, connected by discharge chutes to clean and dewater captured screenings. A Spirotainer of 10 m3 capacity was provided for screenings storage. The Halls Head site didn’t have a facility for grit removal, so a cross-flow type grit tank was constructed downstream of the new screening channels. The two contracts were undertaken concurrently and completed ahead of schedule.

“The project has been linked in and commissioning is taking place. Well done to GO and Project Team. Safe, under budget and ahead of schedule!”
George Golowyn Principal Project Manager, Water Corporation