Grease Trap & Floor Drain Cleaning Guide

How Do You Keep Kitchen Drains and Grease Traps Clean? Clear floor-drain grates of debris every day, brush the channels with detergent weekly, dose drains with an enzyme treatment weekly, and book a licensed grease-trap pump-out at the interval your council or water authority sets. Drains and grease traps are the parts of a commercial kitchen most likely to be neglected and most likely to cause a pest or odour problem. Getting the routine right protects food safety, keeps the kitchen usable, and keeps you on the right side of trade-waste rules. Why Drains and Grease Traps Matter for Food Safety Floor drains and grease traps are magnets for pests and a common source of odour. Food debris and grease feed a biofilm — a slimy microbial layer — that lines drain walls and trap chambers. That biofilm attracts cockroaches, drain flies and rodents, and every one of those pests can carry contamination onto food-contact surfaces. The Food Standards Code requires food premises to be kept clean and free of pests. Drains are explicitly in scope because a blocked or filthy drain can back up wastewater onto the floor, creating a direct contamination and slip hazard. A grease trap that is never pumped will eventually overflow, sending fats and food solids into the sewer and breaching your trade-waste agreement. Daily and Weekly Drain Cleaning Routines Most drain problems are prevented by small, consistent tasks rather than occasional deep cleans. Build the following into your daily and weekly cleaning schedule. Daily: Clear visible food debris from floor-drain grates and scrape it into the bin, not down the drain. Daily: Flush drains with hot water at close-down to carry residue through. Weekly: Lift the drain grates and scrub the channels and grate undersides with a stiff brush and detergent. Weekly: Apply an enzyme or bio-active drain treatment to break down the biofilm that harbours flies and odour. Monthly: Check that grates sit flush and are not cracked or missing, which lets pests and debris in. Do not rely on caustic drain cleaners as a routine. They damage pipework over time and do little against established biofilm — enzyme products digest the organic layer that chemical cleaners simply push along. What Are the Grease Trap Pump-Out Rules? Most councils and water authorities require licensed grease-trap pump-outs at set intervals, commonly every 1 to 3 months, with the exact frequency based on trap size and how much grease your kitchen produces. Your trade-waste agreement or approval will state the required interval. Some authorities move to a performance-based schedule where the trap must be pumped before the fat, oil and grease layer exceeds a set proportion of the trap's depth. A grease trap works by slowing wastewater so fats float to the top and solids sink, allowing cleaner water to pass to the sewer. When the accumulated layer gets too thick, that separation fails and grease escapes downstream — which is exactly what causes fines and blockages. Only a licensed liquid-waste contractor may pump out and dispose of the contents, and they must give you a disposal receipt. Controlling Odour and Pests Around Drains Persistent bad smells or small flies hovering near a drain almost always mean biofilm has built up inside it. The fix is mechanical plus biological: physically brush the drain, then dose it with an enzyme treatment weekly so the biofilm cannot re-establish. Identify the affected drain by checking where flies gather or odour is strongest. Remove the grate and scrub the channel walls and the underside of the grate. Pour an enzyme drain treatment in at close-down so it can work overnight without being flushed away. Repeat weekly and monitor whether fly activity drops. Because drains sit at the intersection of cleaning and pest control, they belong in both plans. Our cleaning features let you schedule drain tasks and capture proof, and the guides library has practical hygiene explainers for the whole kitchen. Keeping Records for Council and Trade Waste Keep every pump-out certificate and disposal receipt, and log your daily and weekly drain tasks. If a trade-waste officer visits, or a blockage triggers questions, dated records show you have managed the system responsibly. Store pump-out due dates so a lapse never catches you out, and hold the contractor's paperwork alongside your other corrective-action records. What Should Never Go Down a Kitchen Drain? Most drain and grease-trap problems are caused by what goes into them, so prevention starts at the sink and the bin. Fats, oils and grease are the biggest culprits. When poured down a drain warm, they travel a short distance, cool, solidify and cling to pipe walls, gradually narrowing the pipe until it blocks. Scrape and bin solid fat and used oil instead — used cooking oil should go to a licensed oil-recycling collector, not the drain. Fats, oils and grease — bin or recycle; never pour down the sink. Food scraps and coffee grounds — scrape into the bin; use sink strainers to catch the rest. Starchy waste like rice and pasta — it swells and forms sticky masses that clog pipes. Wipes, gloves and packaging — these snag and build blockages quickly. Fit strainer baskets to every sink and empty them regularly. Training the team on what belongs in the bin rather than the drain does more to protect your plumbing than any cleaning product, and it slows how fast the grease trap fills between pump-outs. How Does a Grease Trap Actually Work? Knowing how the trap works makes it obvious why maintenance matters. Wastewater from your sinks and dishwasher flows into the trap, where its speed slows dramatically. That slowdown lets physics do the separating: fats, oils and grease are lighter than water and float to the top, while heavier food solids sink to the bottom. The relatively clean water in the middle passes out to the sewer. Over days and weeks, the floating grease layer thickens and the solids layer deepens. When either grows too large, the clear