What is trade effluent?
Some businesses need to apply to use our sewers for more than just domestic purposes. This is because they produce a lot of contaminated liquid waste that needs treating at our wastewater treatment works. This liquid waste is called trade effluent.
What it is
Trade effluent is any industrial liquid waste (other than surface water and domestic sewage) that’s discharged into a public sewer from business premises e.g. manufacturing, car washes, food processing etc. This liquid waste could be contaminated with: fats, oils and greases, chemicals, detergents, heavy metal rinses, solids, food wastes, soil and more.
What it isn’t
We don’t class it as trade effluent if it’s domestic sewage. This includes wastewater from kitchen sinks, showers, and toilets, and domestically-derived wastewater from hospitals, hotels, caravan sites, restaurants, or educational establishments.
Why do I need trade effluent consent?
Our responsibility
We have a legal responsibility to manage the effluent draining into the public sewer. Highly contaminated waste requires more intense treatment before we can release it into the environment. Your trade effluent license helps us protect our network and our region's water supply.
How is it measured?
Metering - A private sub-meter can be installed on pipework that supplies the trade effluent activities. This helps us quantify the volume of the wastewater being produced (by measuring the amount of clean water being used for the business processes). In some cases, we may stipulate that a discharge meter is required, usually for larger discharges. This measures the flow in the sewer pipe, before the effluent leaves the site.
Sampling - To understand the characteristics of the trade effluent a business is producing, we arrange a site visit to the premises once we've received an application from them. At this visit, we take samples of the wastewater and test it to determine the charging strengths COD & SS. These parameters will determine the unit rate charged by your retailer. This sampling will be ongoing to monitor your compliance with consent parameters and may form part of an annual review of charging strengths.
Charging
Charges are payable in addition to adjusted sewerage charges. Bills will be issued by your retailer who will also deal with any billing enquiries.