How we measure your trade waste

We do this to:

• make sure we are charging you the correct amount for your trade waste. We also consider what kind of business you are in this calculation. 
• understand how much trade waste is released into our sewer network currently, and predict future releases so we can protect treatment plant processes 
• manage the capacity of our sewers. 

How we measure trade waste volumes 

Lots of different businesses discharge their trade waste into our sewer network. There are a few different methods we use to measure trade waste volumes. The type of method we use to establish trade waste volumes depends on:

• each business’ activities 
• each business’ water usage 
• the likely volume of trade waste the business is going to discharge to sewer.  

How we measure trade waste 

We’ll use one of the following methods to measure your trade waste volume. 

Factored potable water meter 

To measure your trade waste using this method, we apply a trade waste factor to your potable water amount. This means we measure the amount of potable water that is discharged to sewer as trade waste. 

To do this, we do a water balance test at the site. We’ll typically use this method if your business discharges less than 25 kilolitres per day to sewer and you have low alternative water usage.  Even if we use this method, we might still ask for a flow meter reading.

Agreed volume 

Agreed volume means we agree on the amount of trade waste your business is likely to discharge to the sewer annually or as required. 

We use this method if trade waste volumes can’t be linked to a flowmeter, or potable water usage, like during groundwater remediation activities or contaminated storm water discharges.  

Electromagnetic flow meter

If you discharge more than 25 kilolitres per day,  you will be required to instal a flow measuring device on the pipe that carries the trade waste to the sewer. This is the most accurate method for measuring trade waste flows (and loads, where applicable). Learn more on our electromagnetic flow meters page.  

If you think the method being used to measure your trade waste volume is inappropriate, call 9313 8366, email trade.waste@gww.com.au or speak to your site's assigned representative.