WT10-25/26 Expression of Interest Wetalla Electrical Renewal Project Early Contractor Involvement

Summary and scope

The Wetalla Water Reclamation Facility which treats wastewater generated by Toowoomba and surrounding regional towns needs a functioning and sustainable treatment process to produce an environmentally safe effluent product for reuse or discharge as appropriate.The individual parts that support this treatment process include a Preliminary Treatment Area, Reactor Tank Process, Clarification, Disinfection, Return Activated Sludge, Aerobic Digestion, Sludge Handling and Effluent Re-use and Discharge.Each of these processes are supported by large mechanical plant that are powered through one of two main switchboards; Main Switchboard (MSB) – A and MSB-B. These main switchboards in turn feed smaller Motor Control Centres (MCCs) including the Disinfection MCC, AWTP MCC and Biosolids MCC. MSB-A is fed by a 11kV/415V transformer which is located outside Switch room A and MSB-B is fed by a 11kV/415V transformer which is located outside Switch room B. These two transformers are fed from a TRC owned 11kV RMU.Some of the critical electrical assets supporting the Wetalla Water Reclamation Facility have reached the end of their service life, are exhibiting signs of deterioration, or no longer comply with current regulatory standards—necessitating intervention.Due to the complex interdependencies between systems, compatibility requirements, operational site constraints, and the need for cost-effective delivery, a holistic project-based approach is essential in addressing asset renewals that prioritises strong coordination and risk mitigation.