Have you ever hesitated before pouring rancid milk down the sink, wondering if it’s the right thing to do? What about expired tomato passata, leftover paint water, or pungent oil from a tuna can?
It’s important to consider the consequences of disposing of everyday items down the plughole. Not only can they clog or damage pipes, but they can also pose health hazards and harm the environment. Additionally, they increase the burden on wastewater treatment plants.
Understanding the Destination
All indoor wastewater, including water from toilets, sinks, bathtubs, and showers, travels through the sewer system. These pipes connect within our homes and lead to municipal sewers buried beneath streets or yards, eventually reaching wastewater treatment plants. These plants use bacteria to break down organic matter in the wastewater.
The organic load, measured as “chemical oxygen demand,” increases with every additional item poured down the drain, from milk to tuna oil. This higher load necessitates more aeration and larger tanks, making wastewater treatment more complex and costly.
The Dangers of Milk
Pouring milk down the sink can lead to blockages in sewer pipes. Dairy products and items containing fat, oil, or grease can solidify and combine with other waste, forming obstructions called “fatbergs.” Sydney Water spent A$12 million in nine months dealing with over 11,000 pipe blockages.
Clogged sewers not only inconvenience water utilities but also release untreated sewage into the environment. To prevent this, Sydney Water recommends diluting old milk with water and using it to water plants or disposing of it in the garbage.
Expired sauces, dips, and gravy can be composted or absorbed with paper towels and thrown in the trash. Avoid pouring concentrated cleaning liquids like bleach down the sink, as they can harm plumbing systems and pose health risks.
Proper Disposal of Chemicals
Instead of pouring paint or cleaning water down the drain, consider using disposable brushes or properly storing them. Hazardous household chemicals should be taken to Household Chemical Cleanout events for safe disposal.
Industries have established collection schemes for items like paint, ensuring proper recycling and treatment. It’s crucial to adopt safer disposal methods and not use sinks as waste disposal points.
A Collective Responsibility
Every action contributes to the overall health of our plumbing infrastructure, public health, and environment. By composting, attending chemical cleanout events, and recycling hazardous materials, households can make a significant impact in protecting waterways and ecosystems.
Faisal Hai, Professor and Head of School of Civil, Mining, Environmental and Architectural Engineering, University of Wollongong
This article is republished from The Conversation under a Creative Commons license. Read the original article.
