The Dishwasher Debate answers the question "Should dishwashers discharge to the sewer via a GRU?"

On 25th July, WRc hosted a highly anticipated event titled "The Dishwasher Debate" at their training centre in Swindon. The discussion brought together leaders from water companies, dishwasher manufacturers, industry bodies, and catering industry consultants to discuss and debate the connectivity between commercial dishwashers and Grease Recovery Units (GRUs) in commercial kitchens. The central question was whether dishwashers should be connected to a grease management system, such as a GRU.

The debate aimed to explore different perspectives and reach a consensus on managing fats, oils, and grease (FOG) discharge from commercial dishwashers.

The event was a continuation of the discussions held during the European FOG Summit in 2022. Water companies, represented by United Utilities, and industry representatives at the forefront of FOG production and disposal, represented by the Foodservice Equipment Association (FEA), convened separately to formulate their position statements.

The debate was opened by Matt Hart (Operations Director, WRc), who noted how the landscape has changed over the last 15 years, with everyone in the water industry now trying to do the right thing and everyone outside of the water industry having a low toleration and high expectation of accountable companies.

"Today is a special day”, said Matt, "It is exciting when like-minded changemakers join forces to discuss two critical position statements."

Water company and foodservice industry position statements

Tony Griffiths from United Utilities presented the water companies' position statement, supported by Water UK. It outlines that if a dishwasher unit is used solely for sanitisation purposes, it should be connected downstream of the Grease Recovery Unit (GRU). If the dishwasher is intended for washing, it must be connected upstream of the correctly sized and configured GRU.

The position statement will be published on the Water UK website and utilised by water companies to guide foodservice establishments (FSEs).

Andy Threlfall, Technical and Policy Director at the FEA, shared the perspective of the foodservice equipment industry. A survey of approximately 200 FEA members revealed a mixed response on connecting dishwashers to grease management systems. A significant portion of members (less than 20%) needed a grease management system and cited reasons such as cost, space constraints, and reliance on chemical-based solutions.

Panel discussion: "The Dishwasher Debate"

A panel discussion followed, featuring experts from different fields to evaluate the statement: "A dishwasher should be connected directly to a GRU." Key points raised during the discussion included the need for collaboration, clarity, education and minimum standards. Thames Water's representative emphasised the importance of educating FSEs about the consequences of non-compliance and stated that they would - as a last resort - prosecute non-compliant establishments without a grease trap connected to the wastewater network.

Interactive poll: the attendees weigh in

• Poll results indicated that the majority of attendees believed that dishwashers should be connected to a GRU.
• The main purposes of the position statements were identified as (ranked in order) providing clarity, awareness, guidance, understanding, education, perspective, and information.
• The attendees' collective opinion showed strong support (89%) for connecting dishwashers used as a washer (rather than purely as a sanitiser) to a grease management system.

Peter Henley, Principal Consultant (Wastewater Infrastructure) at WRc, summarised the event's key takeaways. He noted that all speakers and attendees were committed to effectively addressing the challenges faced by FOG in wastewater. 

The consensus among participants was that minimum standards were necessary and could be achieved through collaboration and education, ultimately leading to greater clarity in FOG management.

In conclusion, the debate successfully focussed on the issue and collectively achieved the desired consistency, as water industry representatives generally agreed that dishwashers should be connected to a GRU at the relative point of use. The event fostered constructive discussions and showcased the participants' dedication to finding effective solutions for FOG discharge in commercial kitchens.