A couple years ago, I finally caught up to the reality that lining trash bins with plastic bags is not only a relatively useless endeavor, but also harmful to the environment. It contributes to the acute recycling contamination problem which almost single-handedly kills the entire recycling economy. It also results in a HUGE amount of plastic ending up in landfills or our water.

Do people really care about having a pristine looking garbage can? Am I missing something...its a garbage can right? A garbage may very well look or smell a bit like...garbage. Furthermore, if you really care about smells and cleanliness, throwing everything you can in the compost bin and quick rinsing your dirty recyclable food containers will keep your bins pristine without any plastic liners involved.

Lets look at some 'back of the envelope' calculations to appreciate the magnitude of using plastic liner bags.

  • If every household used 2 plastic liner bags a week (one for recycling and one for trash), that's 104 liner bags per year.
  • Each liner bag is approximately 8 square feet of plastic material (2' x 2', 2 sides)
  • A box of 140 liner bags approximately costs $20, or about $15 a year
  • There are 2.6 million households in the bay area

If every household in the bay area used 2 plastic liner bags a week....

  • Roughly 9 million pounds of soft plastic waste created
  • (104 * 8 sq ft * 2.6 million) = over 2 billion sq ft, or over 77 sq miles

So SF Bay Area households can cover San Francisco entirely in a thin layer of plastic liner bag every 7 months. Of course these quick calculations may be a factor for 2 or more off in either direction (hopefully many households do not use plastic liners, but I did not include business/commercial plastic bag liner waste which may be a worse offender).

So the benefit of this huge environmental cost is to keep our garbage bins clean? Seems like a bad deal. Not to mention if you took that $15/year in plastic bags and threw it in a (historically, inflation adjusted) CAGR 7% US index fund, you end up with over $3000 extra in your pocket over 40 years: enough for an extra vacation or two in your lifetime.

Hopefully we can appreciate the many reasons to stop using plastic liners entirely or, if that's not possible due to roommates, try reusing them several times before tossing them out (you can easily get 5+ uses out of each plastic liner).