Trade waste introduction

Generally any liquid waste generated from business, trade or manufacturing processes, other than domestic sewage, is defined as trade waste. Untreated trade waste that contains prohibited substances such as flammable liquids, grease, acids and solids may block the sewerage system, damage components, adversely affect the treatment process and increase costs to the community. Household waste, such as toilet waste and water from bathrooms, kitchens and laundries is referred to as domestic sewage and should not be confused with trade waste. 

There is a misconception that trade waste is always toxic and is only generated by industrial factories. In fact, trade waste includes wastewater generated by many processes including but not limited to air conditioning units, commercial kitchens, car washes, degreasing and processing operations, food outlets, laundromats, service stations, vehicle repair workshops, equipment hire centres and animal boarding kennels. Only waste that can be treated biologically through Council's treatment processes is allowed to be discharged to the sewer.

Oil and grease pose a particular problem. All owners of premises with trade waste grease arrestors must hold a current Trade Waste Approval to "Discharge to Sewer", which will outline cleaning requirements for grease arrestors and oily water separators. Arrestors must be cleaned out by licensed liquid waste transport operators.

Petroleum waste may cause dangerous gas build up in the sewer system. Acid and strong chemical waste corrodes sewerage components. Strong dye affects the colour of treated effluent. High levels of detergent such as those discharged from commercial laundries create heavy foam and cause nutrient problems.

Rain water and surface run-off from stormwater should never be diverted to the sewerage system as it adds volume which can cause sewage overflow during storm events while also increasing pumping and treatment costs. This results in higher costs to Council and increased rates to property owners.