Retail food trade wastewater

Compliance, savings and sustainability go hand in hand

Removing solids, oils and grease from your wastewater at the source helps reduce the number of blockages and overflows on your property, in our system and in the environment. Whether your business is a restaurant, café, commercial kitchen or takeaway, we can help you to save water, save money and do the right thing by our waterways.


Using sinks, toilets, drains and grease traps as garbage bins might seem an easy option, but they’re not rubbish bins.

Never put food scraps or waste oil into a sink or grease trap.

The Don’t even SINK about it campaign was created in partnership with Restaurant & Catering Australia (R&CA)The aim is to help businesses like yours not only understand our wastewater requirements, but add to your bottom line by saving water and managing waste more sustainably.

Check out our 5 practical Don't even sink about it fact sheets. They were developed especially for retail food businesses like yours. They'll help you understand and minimise the impacts of your retail food trade wastewater.

Check out our retail food trade fact sheets

Fact sheet What you'll learn

How the wastewater system works

The waste from a food business has a much higher concentration of fat, oil and grease than your average home and there’s a lot more of it. Find out how we deal with it, and what you can do to help.

Managing waste in your food business

Solid waste like food scraps should go in the bin, and liquid waste like cooking oils should be recycled. It's easy to adopt sustainable practices in your food business.

Saving water in your food business

Save money by managing water efficiently and contribute to a sustainable environment. Follow these practical tips for creating a better life for you, your staff and Greater Sydney.

Pre-treatment equipment: Everything you ever wanted to know about grease traps

What you put into the sink can end up in our oceans and rivers. Find out what you can do to help prevent solids from blocking your plumbing and our wastewater system (sewer), and disrupting treatment processes.

What commercial business customers need to know

What are your obligations, and what services do we offer? Find out about our agreement with you, our services, fees and charges.


An in-floor bucket trap may be one of your requirements.

Your business requirements

Retail food businesses (and any other business using a grease trap to discharge wastewater) must have a connection agreement. So before you start operating your business and installing your pre-treatment, go to Sydney Water Tap in and apply to discharge trade wastewater into the wastewater system. Simply follow the steps in the approval to discharge commercial trade wastewater process.

Before we can give our approval, your business will have to meet our requirements, which will probably include:

  • an approved grease trap installed by a licensed plumber and properly maintained 
  • in-floor and in-sink waste bucket traps in all prep sinks and floor wastes in all food-preparation areas
  • a boundary trap with a gravity connection to our wastewater system
  • a backflow containment device at the property boundary or directly after the water meter
  • a tap within 5 metres of any pre-treatment equipment (such as a grease trap) with a backflow prevention device on the inlet side of the tap.

You must not pour waste oil down the drain or into your grease trap. Instead, collect any waste oil from deep frying or barbecues and store it in sealed containers in properly bunded areas and have an oil recycler collect it. If you have a grease trap, you must use an approved Wastesafe transporter to clean it (pump it out) at the frequency we set.

Find out more from these fact sheets: What commercial business customers need to know. and Pre-treatment equipment: Everything you ever wanted to know about grease traps.


Protect waterways, and add to your bottom line

All wastewater enters our system as biosolids, recycled water or treated wastewater. We're equipped to handle it. But discharging solid materials and grease in your trade wastewater has consequences. It has the potential to damage your property’s plumbing and our wastewater system. Blockages smell bad, cause overflows and are expensive to fix. Wastewater overflows have a huge impact on our waterways.

By managing your resources and disposing of waste responsibly, you can help protect Greater Sydney’s waterways – and maybe even add to your bottom line. You can do it. See our Saving water in your food business fact sheet.


Tips for managing waste

  • Be creative with your menu. Develop dishes that use all your ingredients. Nose-to-tail and shoot-to-root cooking means less goes to waste.
  • Don’t throw away leftover ingredients you’ve already prepped. See if local charity organisations would welcome them to provide meals for people in need.
  • Try pickling or fermenting leftover prepped vegetables instead of throwing them away.
  • Compost your vegetable scraps.
  • Support local suppliers by purchasing local, seasonal ingredients. They’ll be fresh and tasty, and you’ll be minimising the environmental impact of transport.
  • Feature sustainable proteins on your menu. For example, use third-party verified products, or hormone-free meat from a local farmer.
  • Promote the doggy bag. You’ll have less waste for you to deal with and you won’t have to throw as much food away. Supply compostable, biodegradable or reusable containers, and encourage customers to bring their own.

  • Never pour used cooking oil into a sink or grease trap.
  • Scrape leftover food into the bin or compost, not into the sink.
  • Dry-wipe plates to remove leftover oils, meat juices and sauces instead of rinsing.
  • Use sink strainers to catch solid food waste when you’re preparing meals.
  • Wipe or sweep spills – don’t hose them into drains.
  • Avoid using bleach or caustic soda. Choose environmentally friendly products when you can and use as little as possible.

If used cooking oil enters our system, it can have major environmental consequences and block our pipes.

  • Collect cooking oil you can’t reuse in sealed containers and store it in a bunded area (an area where leaking oil can’t escape) ready for your oil recycler to collect and recycle off-site.
  • Have the right sized grease trap for the volume of waste oil your business produces, and never pour waste oil directly into the grease trap.
  • Find the balance between cooking great food, reusing cooking oil and saving on recycling. Deciding how often to change deep fryer oil depends on what sort of oil you use, how many hours it’s in use, how often you use it, what temperature it’s heated to, and how clean your equipment is.

  • Offer tap water rather than bottled water to customers to reduce plastic waste.
  • Use compostable, biodegradable or reusable containers for takeaway and encourage your suppliers to do the same. The food service industry uses tonnes of single-use containers in the supply chain that eventually end up in landfill.

  • Check fixtures and appliances for leaks. A hot water leak wastes both water and energy.
  • Understand your water and energy use. Watch for changes over time that might indicate a leak or that equipment needs maintenance.
  • If you need to pre-rinse plates and cutlery, use cold water from a water-efficient smart rinse valve.
  • Investigate water-saving equipment like waterless woks, and efficient dishwashers, ice makers and bottlewashers.
  • When it’s time to upgrade plumbing and fixtures, bigger isn’t always better. Get the right sized dishwashers and bottlewashers for the number of covers you serve, and only run them when they’re full.
  • Don’t use maximum water temperatures when washing up. A reduction of even a few degrees will save energy and money.

  • Place bins in the toilet to discourage patrons from flushing sanitary items, wet wipes and paper towels. Wet wipes alone cause about 75% of blockages.
  • Display posters letting customers and staff know what’s okay to flush down the toilet – and what’s not.
  • Display posters reminding customers and staff to turn off taps when they’ve finished washing their hands.
  • Learn how to protect your plumbing and help prevent overflows.

What's in your wastewater

Commercial trade wastewater from retail food businesses contains organic material that can cause odours and accelerate corrosion in our wastewater system. It also contains greasy waste, which can become solid and block our systems, causing wastewater to overflow into the environment or even backflow into your premises. By producing less waste and following the requirements of your connection agreement, you can minimise the impacts of your retail food trade wastewater.

Pollutants and impacts from food retail businesses

Source

Possible effects

Food solids
Trade wastewater contains food particles from plate leftovers and pot cleaning.

  • Blocked drainage within your premises, creating expensive plumbing bills
  • Damage to our pumps and extra load on the wastewater treatment processes, making it more costly to treat the wastewater
  • Blocked wastewater pipes, causing wastewater to back up and overflow

Fats, oils and grease
Trade wastewater from washing up includes food particles and sauce, gravy, salad dressing and meat juice residue.

  • Blocked drainage on your premises, creating expensive plumbing bills
  • Blocked wastewater pipes, causing wastewater to back up and overflow

Biochemical oxygen demand (BOD)
Trade wastewater contains small particles of food, gravy and sauce residues and sugars. This organic material is a readily accessible food source for micro-organisms present in the wastewater system (sewer).

  • Odours in your premises or in the wastewater system
  • Accelerated corrosion in our wastewater system, causing wastewater to leak into the environment and require costly repairs

Temperatures above 25 °C
High-temperature dishwashers release wastewater at high temperatures.

  • Accelerated corrosion in our wastewater system, causing wastewater to leak into the environment and require costly repairs
  • Barriers that stop your grease trap from working properly
  • Greasy wastewater entering our system, causing blockages because oil and grease aren't cool enough to separate in the grease trap

Find out more about saving water
See our water efficiency tips for business to learn how to monitor and manage your water use and check out our special offers from WaterFix Small Business and WaterFix Commercial.