Why does it take so long for biodegradable landfill waste to decompose?

The average landfill is expected to take 100 years to decompose the biodegradable waste that is dumped into it. In a lifetime, this means one person could contribute up to 40 pounds of trash or more if they live in an urban area. But why does it take so long for biodegradable landfill waste to decompose? Read on and explore some key factors that may be at play.

Different types of trash accumulate in landfills. Each piece of garbage decomposes on its own time, so even if a part of landfill waste has actually decomposed, it does not show.

Moreover, the world’s growing population means landfills are getting fuller than ever. The absence of oxygen and UV rays needed to decompose biodegradable waste makes it even harder for all these things to break down.

Landfills are too full.

In our homes, it is only natural for us to collect more trash when there are more of us living there. This is also the case in our landfills today. There is just too much junk in the landfills, waiting to decompose. 

Because our trash keeps piling up, landfills are now left with minimal or even zero space for air to get in. Although there is such a thing as anaerobic decomposition, or decomposing garbage without the help of oxygen, this process is slower and could even hamper the entire degrading phase itself. 

Modern landfills are also highly compact. This only means that not only are they deprived of oxygen, but also of dirt. Both oxygen and bacteria are needed for an effective decomposition facility. In the absence of the two, even the most biodegradable waste could take a while to break down.

Some biodegradable wastes have been processed.

This reality also contributes to why a high percentage of biodegradable wastes take longer to decompose. A natural product only stays biodegradable if it stays in its original form. Unfortunately,  modern times require most organic items to be processed so they last longer, making it almost impossible to recycle and completely decompose them.

Petroleum, for example, would have been easily decomposed to crude oil after use. But because it is formed into plastic, it becomes non-biodegradable. This happens to other organic materials, too. 

Once processed, microbes and enzymes no longer recognize the elemental composition of these once easy-to-decompose wastes. This adds to the struggle of overflowing landfills, as trash keeps accumulating without getting decomposed.

People think they are choosing the lesser evil when they turn away from plastic and use paper, for example, not knowing that there is also a huge possibility that paper will stay in its form even after 50 years. 

Research shows that newspapers in landfills stay readable after 40 years, and some steaks still have meat on their bones after 20 years. Such discoveries only show that even biodegradable waste is still a problem, together with plastic and other trash that does not decompose at all.

Modern design and technology could improve the decomposition process in landfills.

An increasing number of landfills are slowly trying to modernize their systems to be more conducive to faster waste decomposition. They now inject water, microbes, and oxygen to aid the process and help speed up biodegradation.

It would be ideal if all landfills would soon follow suit. However, the cost it takes to advance the system makes it improbable for many places. It is a highly expensive upgrade, along with other developments such as separating food scraps from other wastes.

The solution is still waste reduction.

Using less plastic cannot completely solve our problem of waste disposal and landfill shortage. Even paper ends up in landfills and cannot decompose as fast as we expect it to. 

The best way to ensure we’re not adding to garbage issues is to totally reduce the waste we produce. There are a lot of things we can do to help address the growing pains of accumulated waste:

• Reuse as much as you can. Instead of choosing paper cups over plastic, step it up by always bringing a reusable tumbler. Glass and metal tumblers are great choices and will last long, too.
• Recycle your waste. Recycling a part of your trash will help give more space in landfills to accelerate the decomposition there. You can start with the small things, like trying to recycle paper waste.
• Look into creating your own compost pit at home. A big part of the trash we produce everyday could do well in a compost. Food scraps, fruits and vegetable peels, and dried leaves are better off in a pit than the landfill. Don’t have a backyard? You can try making a makeshift pit using a trash bin. Just follow the usual instructions of building one like you would outside.

Common questions about biodegradable landfill waste 

How long does it take for a landfill to decompose?

On the average, biodegradable landfills are expected to completely decompose in between two to six weeks. This varies depending on the amount of waste in the landfill, whether or not air gets in, and if wastes are properly segregated.

Will a biodegradable polymer degrade in a landfill?

Yes, there is such a thing as biodegradable polymers, also referred to as bioplastics. Although tagged biodegradable, they do not degrade as fast. They will only degrade properly when exposed to sunlight, as UV rays break down its molecular particles and decompose them.

Do biodegradable cups break down in landfill?

It all depends on how these cups were processed. If made solely of paper, there’s a high chance they break down. However, it should also be noted that the decomposition process also depends on the landfill condition. In the absence of moisture and bacteria, even a thin sheet of paper would take longer to degrade.

There are a lot of things that need to improve for biodegradable waste to decompose faster in landfills. Making sure oxygen and bacteria are both present in the facility, separating trash by type, and having bigger landfills to avoid overcrowding spaces would all help landfills be more effective at decomposing.