Regardless of your opinion about the Columbia River Crossing project—the proposed $2.6-to-$3.6 billion bridge and interchange project on the stretch of I-5 connecting Portland, OR with Vancouver, WA—the following video is a great example of what is often called “social math.”

Most folks have a lot of trouble making sense of really big numbers.  We know that a billion is bigger than a million, but we don’t really grok how much money a billion dollars really is.  So take a look starting at about minute 1:20, where the video puts $3.6 billion in a context that’s concrete and easy to visualize:  nearly 46 tractor-trailers full of $1 bills.

That’s a lot of singles.  The rest of the video is worth a look too, of course.

Moving past the awesome visuals, there’s an important point in play here:  namely, that the costs of transportation megaprojects have become so enormous that it’s really hard for us to make any sense of them.  You can argue the benefits of the CRC all day long, but the bottom line is that the costs are really, really huge.  Yet in a way, they’re so big that people just can’t pay attention to them—we get lost in the zeros, and just hope that someone else is keeping track of them.  But failing to appreciate the costs creates massive blind spots in our thinking—blind spots that make it easy for us to ignore alternatives that might not satisfy everybody’s dreams, but still meet at least some of our aspirations—though at a much lower cost.

That’s why social math can be so helpful: without illustrations like this, it’s easy to forget that a few billion dollars is a heck of a lot of money to spend on a few miles of road.