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Kitchen deep cleaning - drainage
Every commercial kitchen sends fat, oil and grease towards its drains. Warm and liquid on the way down, it cools and sets in the pipes - and what it sets into is blockages, back-ups, bad smells and a compliance problem.
The short answer
Fats, oils and grease - FOG - leave a kitchen warm and liquid, then cool and solidify inside the drainage, narrowing and eventually blocking pipes. The results are drain back-ups, foul smells, hygiene risk and expensive emergency clearance - and discharging matter that blocks or damages the public sewer can breach the law. Controlling FOG at source is cheaper and safer than dealing with what it does downstream.
What FOG does
The problem with fats, oils and grease is a change of state. Cooking sends them into the drain warm and flowing, so they seem to disappear - but as they travel and cool, they congeal and stick to the inside of the pipes. Layer builds on layer, the bore narrows, and food debris and other waste catch on the greasy lining until the flow is choked.
Left unchecked this is what forms the notorious drain blockages, and on a larger scale the fatbergs that clog public sewers. It is a slow, invisible process happening inside pipes nobody looks at - which is exactly why it is usually discovered only when something backs up.
Cost one
The most direct cost is the blockage itself. A choked drain backs up - into gullies, sinks, or worse, across the kitchen floor - and clearing it becomes an emergency, because a kitchen with a backed-up drain cannot safely operate. Emergency drainage work, at short notice and out of hours, is dear, and a severe blockage can mean closing until it is cleared.
Recurring blockages compound the cost. A drainage system lined with hardened grease will block again and again until the underlying FOG is dealt with, turning what looks like a one-off call-out into a running expense and a repeated interruption to trading.
Cost two
Grease-laden drains smell. Decomposing fat and trapped food debris produce foul odours that drift back up through gullies and sinks into the kitchen and sometimes the dining area - unpleasant for staff and customers and a poor look for an operation that trades on cleanliness. A drain problem is not confined to the pipe; it announces itself.
It is a hygiene issue as well as an unpleasant one. Standing waste and back-ups attract pests and create contamination risk, both of which bear directly on a food hygiene inspection. A drainage problem that started as grease can end up costing marks on the rating and attention from an environmental health officer.
Cost three
FOG is also a compliance matter. It is an offence to discharge into a public sewer anything that could damage it or interfere with the free flow of its contents - and hardened grease that blocks the sewer is exactly that. Water and sewerage companies can, and increasingly do, require food businesses to manage their grease and can pursue those whose discharge causes blockages.
So a kitchen that lets FOG run to the sewer is not just risking its own drains but potentially breaching its duty not to misuse the public system. Grease management is, in that sense, a compliance obligation as much as a maintenance one.
Controlling it
The cheap and effective place to deal with FOG is at source, before it enters the drainage. Good practice keeps grease out of the drain in the first place: scraping and wiping greasy pans and plates before washing, straining and properly disposing of used cooking oil rather than pouring it away, and fitting and maintaining grease traps or interceptors to catch what remains before it reaches the sewer.
A grease trap only works if it is emptied and maintained on a schedule - a neglected one simply passes grease through or overflows. Combined with good kitchen habits, it turns FOG from an invisible, accumulating liability into a managed, contained waste stream - which is far cheaper than the blockages, smells and compliance problems it otherwise causes downstream.
Questions
They go in warm and liquid, then cool and set solid inside the pipes, narrowing and blocking them. Food debris catches on the greasy lining until the flow is choked - causing back-ups, smells and hygiene problems.
Fats, oils and grease - the cooking by-products that solidify in drainage and cause blockages, including the fatbergs that clog public sewers.
It can breach the law. It is an offence to discharge into a public sewer anything that could damage it or interfere with the free flow of its contents, and hardened grease that blocks the sewer does exactly that.
Emergency drain clearance and possible closure, recurring blockages until the grease is controlled, foul smells and hygiene risk that can cost hygiene-rating marks, and potential action from your water and sewerage company.
At source: scrape and wipe greasy items before washing, strain and properly dispose of used cooking oil, and fit and maintain grease traps to catch what remains before it reaches the sewer.
Yes. A grease trap only works if it is emptied and maintained on a schedule. A neglected one passes grease through or overflows, defeating the point.
Our deep cleans reach the greasy areas where drain problems start - part of keeping FOG under control.
