The Coliban Region Water Corporation is seeking submissions for major upgrades to its Bridgewater Water Treatment Plant located 40 km north west of Bendigo in the Loddon Shire, Victoria.
The scope includes the design, supply, and commissioning of a new UV disinfection plant and chlorination tanks.
The Bridgwater Water Treatment Plant serves the townships of Inglewood and Bridgewater, including the residents as well as commercial and industrial customers. The raw water from the Loddon River is treated to create a supply of drinking water.
The plant takes in the raw water and stores it in two settling ponds which can hold a combined total of 20 ML. The facility treats 2.5 ML of water a day, clarifying, filtering, correcting the pH, and disinfecting it. If required, blue green algae is removed by a carbon filter. In 2009, faced with falling quality of the raw water, Coliban Region Water Corporation upgraded the plant, and constructed a desalination plant.
The current upgrade works will address a series of issues in relation to the condition and performance of the water treatment plant, in order to meet the new proposed Health Based Targets to be incorporated in the Australian Drinking Water Guidelines.
The successful contractor will undertake a variety of works around the site, including installing a new 20 kL chlorine contact tank, complete with internal baffles to provide a chlorine contact time of 15 mg/L.min, and a tank inlet free chlorine analyser for sampling the water supplied to the chlorine contact tank.
The chlorine tank section of the work will include pipework, bypass and isolation valves, as well as a reinforced concrete pad upon which the tank will sit. The contractor will replace some of the existing filtered water and blended water pipework as part of the works, and also provide an overflow pipe from the tank, to be connected to the existing clear water storage tank overflow pipework.
The winning contractor will also design, supply, commission and test a new UV disinfection plant, including UV reactors, electrical and control panels, UV lamp cleaning equipment, cleaning and sampling valves, and the associated instrumentation, control equipment, connections to existing and new control systems, etc.
They will be responsible for ensuring the UV reactor designs are certified against the US EPA Ultraviolet Disinfection Guidance Manual, as well as training Coliban Water staff in the sue and maintenance of the UV equipment.
Additionally, the project will require an air-conditioned building mounted on a concrete slab, which will house the UV disinfection system.
According to the Coliban Region Water Corporation, the UV plant will become the primary disinfection barrier, while the chlorine treatment will provide secondary disinfection.
Other tasks the contractor will undertake include replacing treatment plant bypass connections, installing a new floating offtake in the raw water basin, improving the clarifier and filter sections of the treatment plant, and installing a new Powdered Activated Carbon (PAC) dosing system used to provide coagulation aid, including the containing building, a PAC batch tank mixer, a manual bag unloader, a new electrical cabinet with local control panel, etc. All the new equipment will also have to be integrated into the plant’s existing PLC and SCADA system.