Garburators (or garbage disposal unit) may seem harmless enough tucked away in your kitchen sink. Many people feel good about using their garburator. After all, they are saving food waste from the landfill. Right?! But how eco friendly is your garburator?
The cost of garburators
If we’re talking cold hard dollars, then a study a few years back showed that garburators cost Metro Vancouver $2 million a year! $2 million to clean out all the fats, oils, grease, and general gunk that gets chopped up and passed through garburators. Basically our sewage systems were designed to deal with…. well, sewage. When people start using garburators that adds a lot of extra stuff which blocks up the pipes. This means our sewage systems need a lot more maintenance. Hence the $2 million per year bill.
Environmental cost of using a garburator
But, what is the environmental cost of using your garburator? This really depends on what happens to your food waste if it isn’t put down the garburator, as well as what happens to the organics waste in your sewage. Lets think about the former first, as this is the part that we have control over.
If you compost at home, have a curbside collection or a convenient place to take your organics for composting then you should never need to use your garburator. Even if you consider fuel from pick-up vehicles and compostable/paper bags to store your food waste; you (and the environment) are always better to use home composting or local organics collection program for your food waste.
But what if you don’t have a local composting solution. It could be argued that putting your food waste down the garburator is better than it ending up in landfill. Organics that end up in the landfill will rot and putrefy under anaerobic conditions. This rotting creates methane gas; a powerful greenhouse gas. Rotting food in landfill is the second largest manmade source of methane. Therefore by composting food waste, we can eliminate these greenhouse gas emissions. But, by putting food waste down a garburator does not mean it will avoid the landfill. And that leads us nicely into thinking about what happens to organic waste in your sewage….
What happens to your garburator food waste?
Do you know what your city does with its sewage? No? Not many people really give it much thought. There are a few different things that may happen to your garburated food waste once its headed down your kitchen sink. Here are the four common ways to dispose of sewage sludge (in order of environmental preference):
- Land application
This means that the food waste (along with everything else that goes down your drain) is applied as a fertilizer to agricultural land.
Another alternative is for the sewage sludge (including the garburated food waste) to be burnt.
The third option (this isn’t the worst one!) is for the garburated food to be sent to landfill. So after all that energy wasted in your garburator, additional maintenance and load put on the local sewage system, it ends up in the landfill anyway. Where it will rot and putrify and produce harmful gases.
- Ocean dumping
Another, and arguably the worst, option is for the food waste to be dumped in the ocean. Just think about it. All of that garburated waste (along with everything else that goes down our drain) sent out through a long pipe and deposited in our oceans along with all those toxins and pathogens. Hmmmm, not what I would feel comfortable happening to my food waste.
I am not a sewage sludge expert, but needless to say, home composting is by far my preferred option!