A domestic wastewater overflow is when black water (water that comes from your toilet and is contaminated with human waste) or grey water (water that comes from bathrooms, kitchens and laundries) overflows onto your property or into your home. There are a number of measures you can take to ensure any domestic wastewater overflows have minimal impact on your health and home.
The most common causes that we see of domestic wastewater overflows include;
1. Blocked sewerage main caused by tree roots or the build-up of foreign objects such as fats, wipes, toys and more
2. Inadequate maintenance of sewage systems
Any blockage in a sewerage main can cause wastewater to back flow up through the overflow relief gully and empty out in your backyard and around your home. An overflow relief gully is a drain that has a small removable grate and is usually located near a bathroom or laundry on the outside of your house. This gully connects the sewerage main to your internal house-hold plumbing, this is designed to ensure that if your sewerage main were to become blocked, wastewater will overflow out of the relief gully rather than back flow inside your home.
To ensure wastewater doesn't back-flow into your home, it is important that your overflow relief gully:
1. Is not covered by anything — landscaping, tiles or garden beds
2. The grate is in correct working order (not damaged and easily able to pop-off)
It is also important to keep a close eye on your sewerage tank and make sure that any garden or trees are not planted or growing close to the system. The general recommendation for service and maintenance of sewage systems is every 3 months for your aerobic treatment unit and every 2 to 3 years for your septic tank.