Space is the first thing that decides how a grease trap installation goes, and this Marsden tenancy had very little of it. A commercial food service operator wanted to open a new kitchen, yet the only viable tank location was occupied by a rear platform step. The site also fell under Logan City Council, which meant trade waste metering formed part of the approval.
Therefore, the operator brought in Citi Industries to handle the grease trap installation as a do and charge job. Rather than force the tank into an awkward spot, the team reshaped the rear of the property to suit it.
Project Overview
At its core, this was a below ground grease trap installation paired with a complete commercial kitchen plumbing fit-out. However, the survey plan and the council metering requirement shaped almost every decision on site. Consequently, planning the tank position came before any tool touched the concrete.
The crew set a 1,000-litre tank with a Class D lid, vented the system out the side wall, and ran new drainage to each fixture. Alongside that, the internal works brought water, waste, and a new hot water supply into the kitchen.
Key scope items included:
- 1,000-litre below ground grease trap fitted with a Class D vehicular traffic lid
- Full concrete scanning, cutting, removal, and reinstatement across the work zone
- Rear platform step demolished so the tank could sit within the surveyed boundary
- Trade waste drainage set out to the hydraulic plan
- Tank and trade waste vents taken to atmosphere along the side of the building
- Internal trade waste line connecting every kitchen fixture
- One RPZD backflow valve on the nearest hosetap
- Two bucket traps positioned in the commercial kitchen
- One trade waste water meter, installed at Logan City Council’s request
- Pedestrian barricading kept up across the affected area
Challenges
Every commercial kitchen carries fats, oils, and food solids into its wastewater. Left untreated, that mix sets hard inside sewer pipes and chokes the line. For this reason, Logan City Council trade waste approvals call for a sized grease trap and metered discharge before a kitchen connects.
Beyond the usual compliance steps, the layout fought back. The rear platform step sat exactly where the tank needed to go. As a result, the team demolished it and rebuilt the ground level to take the new unit. The boundary line added a second limit, since the survey plan left only a narrow window for the tank to sit legally.
Vehicle access across the rear meant the lid had to bear traffic loads, so a Class D rating was non-negotiable. Meanwhile, scanning the slab beforehand revealed where existing services ran, which kept the cutting safe.
Key constraints on this project:
- Rear platform step had to come out before the below ground grease trap could be placed
- Survey plan confined the tank to a tight position inside the property boundary
- A vehicle-accessible rear required a Class D lid rated for traffic loads
- Logan City Council mandated a trade waste water meter on the discharge line
- Slab scanning preceded all cutting to avoid striking hidden services
Solutions
Citi Industries worked the job in a deliberate order, starting with the groundworks that unlocked everything else. Each stage below builds on the one before it.
Reshaping the Rear and Setting the Tank
To begin, the crew stripped out the rear platform step and graded the ground for the new unit. With the area clear, they scanned and cut the slab, then dug to depth. A grease trap is a buried chamber that intercepts fats and oils, holding them back while clean water continues to the sewer.
Next, the 1,000-litre tank went in with its Class D lid, seated precisely inside the surveyed boundary. Once bedded, the team poured fresh concrete to close the surface. For sites with similar access headaches, our range of below ground grease traps suits tight footprints.
Drainage and Side-Wall Venting
With the tank in place, attention turned to the pipework. The crew laid the trade waste drainage to the hydraulic plan, carrying flow from the kitchen, through the trap, and on to the sewer. Both the tank and the waste line then vented up the side of the building to the atmosphere.
Venting matters because trapped gas builds pressure and pushes odour back indoors. Under Queensland regulated plumbing work requirements, open venting is part of a compliant system. Subsequently, the internal line was extended to pick up every fixture in the kitchen.
Metering, Backflow Protection and Bucket Traps
Because Logan City Council required volumetric data, the team fitted a trade waste water meter on the discharge. This device records how much trade waste leaves the premises, which informs the council’s charges. In turn, the operator gains a transparent record of usage.
The crew also added an RPZD backflow valve at the closest hosetap. This guard stops dirty water siphoning back into the drinking supply. On top of that, two bucket traps were dropped into the kitchen to catch solids at floor level, easing the trap’s workload between pump-outs.
Bringing the Kitchen to Life
Finally, the internal fit-out tied everything together. The team roughed in cold and hot water, completed the sanitary plumbing, and mounted a hand basin with a base basin mixer plus a sink mixer. A wall-mounted Stiebel Eltron three-phase instantaneous unit now heats water on demand for the kitchen.
An instantaneous heater skips the storage tank, so hot water arrives only when a tap calls for it. Our commercial plumbing services take a fit-out from bare rough-in through to a working, tested kitchen.
Final Outcome
What started as a blocked, awkward rear corner ended as a compliant, working plumbing system. Citi Industries wrapped the Marsden job in December 2025, clearing the site without disrupting neighbouring units. As a result, the kitchen now discharges legally, and the council has the metering it asked for.
- Tank seated cleanly inside the property boundary after the platform step came out
- Class D lid matched to a rear that takes vehicle loads
- Trade waste water meter live and reporting to Logan City Council
- Backflow valve, two bucket traps, and a three-phase hot water supply all commissioned
Since the build followed plumbing compliance and standards Australia, the operator holds a system that will pass inspection and last. The reinstated slab leaves no sign of how tight the job really was.
Final Thoughts
A kitchen’s compliance does not end on opening day. The trade waste system has to keep metering, keep flowing, and keep odour out long after the first service. Yet a rushed install tends to surface its faults early, whether through a failed audit or a slow drain.
Citi Industries treats the first install as the one that should last. Because of that, operators sidestep the callbacks and re-inspections that plague corner-cutting jobs. The team reads the survey, works to plan, and satisfies council conditions before signing off.
So whether you are opening a fresh kitchen or untangling a non-compliant one, talk to the team. We can book a trade waste site assessment and hand over the paperwork that keeps the council happy.
Call Citi Industries on 1300 002 484 to discuss your project.
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