Avoid wastewater overflows

Wherever you see a wastewater overflow, remember that it's sewage. Please be sure to stay away and stay safe, and follow any instructions we provide.

Stay clear of wastewater overflows and obey our warning signs. It's the most important thing you can do to stay safe.

• Don't swim or go fishing in an affected waterway.
• Don't drink water from an affected waterway.
• Pay special attention to children and pets.
• Keep away from machinery, hoses and other equipment we're using to clean up.
• Keep away from overflowing access chambers or maintenance holes.

Wastewater comes from sinks, showers and toilets. It's transported through our wastewater pipes for treatment. Overflows can happen wherever there are wastewater pipes: in bushland, in waterways, in parks, on the street or in your own backyard. They're usually caused by a blockage in the pipes or heavy rainfall, or both.

Something is blocking the pipes

This is often called a dry weather overflow or choke. A partial or complete blockage of a wastewater pipe will reduce its capacity. If the blockage is severe enough, wastewater will back up and eventually overflow.

• The most common cause of blockages are tree roots that find their way into the pipes.
• Blockages are also caused by things like wet wipes, facial tissues and hygiene products flushed in toilets (anything other than pee, poo and paper), and fats, oils and grease poured into sinks.

Wastewater pipes are designed to allow for extra flow during wet weather. However, during very heavy rain this may not be enough. Extra water can enter the wastewater system through cracked pipes, faulty joints between pipes, around the lids of maintenance holes, and by direct connection of stormwater pipes.

Avoid areas impacted by a wastewater overflow and keep children and pets away from them. Stay outside barricades, well away from overflows, vehicles and heavy equipment.

Reasons why you should keep your distance:

• Wastewater contains harmful microorganisms such as bacteria, viruses and protozoa. These can cause illnesses like gastroenteritis if you have direct contact with wastewater or surfaces contaminated by wastewater.
• There may be additional danger from heavy equipment and moving vehicles while we do essential repairs.
• Wastewater that overflows into the environment can also harm sensitive species of flora and fauna.

Once we've removed our warning signs and barricades, you'll know the area is safe.

We use NATA-accredited labs to sample and test waterways. We test throughout the clean-up, and we continue cleaning until the lab results prove that the site has been effectively cleaned. This can take longer in bushland or natural areas. Our clean-up efforts are regulated by the NSW Environmental Protection Authority (EPA) and NSW Health.

Once we've physically cleaned the site, and contaminated surfaces are dry and exposed to sunlight, dangerous levels of microorganisms will be gone. The area will be safe to enjoy again.

Our strict overflow management process

We follow a strict process that's been agreed by regulators to manage wastewater overflow incidents:

1. The wastewater overflow is reported to us.
   
2. A technician goes to the site to verify wastewater overflow and assess the impact on both community safety and the environment.
3. We install containment immediately to stop the overflow from travelling further. We also put up signs and barricades to keep the community informed and safe.
4. The choke crew clears the blockage in the pipe using a high-pressure water jetter.
5. The clean-up crew removes all wastewater solids and contained liquids. It then cleans up the impacted area.
6. Signs and barricades won't be removed until we've completed important checks. The clean-up leader walks the site to verify the clean-up is complete. Then an environmental specialist takes water samples for laboratory assessment. Their lab sample confirms the site is back to its pre-overflow condition.
7. The wastewater overflow is resolved and the site is back to normal.