The GMWC Septage Receiving Building was commissioned in 2019 where the treatment process initiates with preliminary treatment. Septic trucks offload septage, which then passes through a flow meter, rock trap and a grinder and is washed on a conveyor system that removes very heavy solids. The septage waste is pumped from the tank to the inlet chamber ahead the bar screens where it becomes a constituent of the wastewater to be treated.

Septage offload at the station is mostly from residential or commercial septic tank systems and less frequent from industrial processes, as indicated in their respective Approval to Operate issued by the NBDECC.