I had expected the use of plastic bags to decline with the new 5-cent a bag tax in Washington, D.C., but the change came exceedingly fast. In the first month the tax was enacted, plastic base use dropped 87%. According to the Washington Post:

In its first assessment of how the new law is working, the D.C. Office of Tax and Revenue estimated that food and grocery establishments gave out about 3 million bags in January. Before the bag tax took effect Jan. 1, the Office of the Chief Financial Officer had said that about 22.5 million bags were being issued each month in 2009.

I actually noticed a dramatic behavioral difference when I was in Denver, which has no plastic bag tax. Grocery store clerks do not routinely ask, as they do here, "Do you want a bag?" Instead, they just pull one out. The result: people use a lot more bags.

In D.C., the money collected is being used to clean up the Anacostia, which empties into the Potomac River. This is a no-brainer incentive for positive consumer behavior, especially when the cost is so minimal and easy to avoid. Imagine if a simple act like this went national? 

- Samuel Fromartz