Can anyone make a case that we ought to ban plastic bags? I mean a serious case -- one that totes up their benefits as well as their costs?
I know that this isn't it:
Many city officials and environmental groups want to eliminate plastic bags altogether since they take up valuable landfill space, are harmful to creeks and litter public areas. City leaders estimate 1,000 tons of plastic bags are placed into our landfills just from Austin.
. . .
One local environmental group, Bag the Bags, estimates Austinites use more than 100 million plastic bags every single year.
They take up valuable landfill space? I'm not so sure landfill space is all that valuable. But let's suppose that it is. Why would you start with plastic bags? 1,000 tons sounds like a lot (assuming it's not an exaggeration), but Austin collected 135,000 tons of garbage in FY 2007. Plastic bags comprised just 0.74% of our garbage by weight, and probably less by bulk, since you can compact them down to nothing. And why would paper bags -- the obvious substitute -- take up any less space? We'd probably need more space, since paper bags tend to be bigger than necessary, meaning extra wasted material.
Harmful to creeks? Yes, they are. Just off the top of my head, here are some other things that we don't want in creeks: paint, batteries, ammonia, deodorant, plastic bottles, plastic straws, plastic forks, soda cans, tin foil, tin hats, granola bar wrappers, the little plastic cups that Jello pudding comes in . . . . and a gazillion other things. All end up in creeks sometimes. We wouldn't even think about banning them just for that, though. We'd only think about a ban if too many of them were ending up in creeks, and the problem couldn't be controlled more cheaply (say, through periodic community clean ups), and they weren't too useful. In other words, we'd insist on a cost-benefit analysis. Where's the one for plastic bags? Maybe bags end up in creeks more often then other stuff (what about bottles and cans?), but that is because they are ubiquitous. They are ubiquitous because they are so useful.
Litter public areas? So does all the other litter that litterers litter with. See previous point. (Some people actually use plastic bags to carry away their litter, something you can't say about the more respectable trash.)
I've heard the petroleum argument, too. It supposedly takes 430,000 gallons of oil to make 100 million plastic bags. Let's see, roughly 700,000 Austinites using roughly 100 million pb's per year, indirectly consuming 430,000 gallons of oil per year . . . that works out to an average of about 0.6 gallons per year per Austinite. For my car, that's the equivalent of 15 miles per year (city driving). I hereby pledge to drive 1.25 fewer miles per month if I can keep the bags. (Maybe I'll stay home from work tomorrow as a sign of good faith.)
Now I could see how paper bags might be better for fighting global warming. Using lots of paper bags would increase the demand for trees, which would cause more trees to be planted, which would absorb more carbon dioxide from the atmosphere. But environmental groups say paper bags take a lot more energy to make (which actually seems plausible).
Whatever the costs, we also have to consider the utility of pb's. You can carry things with them. Even wet things. They're stronger than paper bags, you can get them in the right size, they are more elastic than paper and resist punctures better. You can wad them up in a plastic-bag holder until you need them again, which makes it easy to use them multiple times. And you can put stinky diapers in them, perhaps their best and highest use. (No, we don't use cloth diapers. I can assure you that the disutility to me of using cloth diapers wildly exceeds the externalities I cause by using disposable diapers.) One creative soul even makes dresses out of them (but wants to ban them).
If there is a good case for banning the bag -- one that balances real costs against real benefits -- I'd be interested in hearing it.
