Water pollution is much worse than solid waste in that it cannot be geographically contained. In other words, you get a whole lake of water with mild contamination instead of a small stack of soil with high contamination.
To decompose a cup of coffee (120ml), 1,800 liter of water is required. Complex technicality set aside, this means your cup of coffee includes 1.8 grams of substances to be decomposed by the microorganisms in water. If you use kitchen towels to absorb the remnant of coffee, you contaminate a couple of paper sheets. But if you throw it into the sewer, you contaminate as much as 1.8 tons of water. A simple story indeed.
Then why do garburators (garbage disposal) matter here? Garburators let you dump solid wastes into the water! A spoonful of spaghetti can be disposed of in solid form and occupy a tiny part of a landfill, if you dump it in the garbage can. But if you flush it down your kitchen sink using the garburator, it will contaminate some tons of water in no time.
When I first arrived in Canada, I was surprised by people’s indifference to this problem. A part of the reason would be Canada’s plenty water resources. I met a very well-educated lady in her 30s who held positive views about environmental protection. While talking on the topic of environment, I found out that she had never thought of garburators as a polluting device. It took me quite a while to make her see the point. Perhaps this is only natural, because most of us do not question the way we live our lives.
There are disputes about this matter, sewage versus landfill for food waste. The best solution for food waste is composting. But if you have to choose between sewage and landfill, I would suggest landfill. My primary reasoning is the scarcity of water resources. Even worse, the vast majority of water resources – be it seawater or fresh water – is common goods, which means nobody is given the ultimate responsibility to protect them. That is why we have several “trash islands” floating around in the high seas.
Stop using garburators. There are alternatives. You begin making changes.