For the past year or so, steel shipping containers have been piling up on every vacant commercial lot in every town in America, offered for sale or lease. What's up? Is there a new, better way to ship and deliver bulk cargo? Or has there been a decrease in shipping due to the worldwide recession? Could shipping containers provide a low-cost housing alternative?

—Brent McGregor

Past year? Buddy, empty shipping containers have been piling up for decades. Not just in the lot across the street, incidentally, but also on the ocean floor, which accepts thousands of the steel boxes annually—they fall off boats in bad weather, etc. This has risen to the level of a capital-P problem, with the National Oceanic and Atmospheric Atmospheric Administration publishing a 2014 study of the containers' effects on aquatic ecosystems. Short answer? Not great.

But that's a question for another day. Back on land, the reasons for the glut of intermodal cargo containers, as they're called, are neither mysterious nor particularly complicated. Take the relationship between the U.S. and China. The relative strength of the American dollar, paired with the weakness of the Chinese economy, means we're currently buying a lot more stuff from them than they are from us. So a ship laden with iPhones crosses the Pacific to the Port of Los Angeles, unloads, and ... then what? It either takes the empties back, or it leaves them behind. Extrapolate this over the vast, intricate web of various international economic relationships—and consider that moving those empties around the globe accounts for 5-8 percent of shippers' operating costs, maybe $20 billion a year all told—and you're looking at a whole lot of accumulated empty containers. As I say, it's been a problem for a while: Back in 2001, for instance, the Chicago City Council passed an ordinance limiting the height to which empty containers could be stacked—they were becoming an eyesore.

Before we go on, though, let's pause for a brief appreciation of containers. Prior to their invention, things were basically thrown onto boats willy-nilly, which as you can imagine wasn't ideal for business—for one, it took forever to load a ship that way. In 1956, a North Carolina trucking-company owner named Malcom McLean started moving cargo in stackable containers (wheelless trailers, essentially) that could be transferred straight from truck to boat. It made so much sense that a mere five years later, the federal government announced it'd give subsidies only to ships configured to carry such boxes. International sizing standards soon emerged, resulting in the Lego-like multicolored stacks of 8-foot-wide containers, mainly in lengths of 20 or 40 feet, seen on cargo ships today. This was such a boon for efficiency that within 20 years the cost of shipping from North America to Asia dropped by half; The Economist has argued that containerized shipping has been more important to globalization than 50 years of trade agreements. (As ever with globalization, not all benefits have been equally distributed: The ease with which American cotton could be shipped to China and shipped back in the form of T-shirts helped sink the U.S. textile industry.)

OK, yay for American ingenuity and all that. But what the hell do we do with all the empty ones? You're not the first to suggest they could be used as dwellings; this is one of those trendy ideas that the media marvels over every few years, and it's been tried here and there. Containers could house the homeless, the thinking goes, or provide temporary lodging in the wake of natural disasters.

There's a catch or two, though, as pointed out in a 2011 article at the architecture website ArchDaily. Designed to stand up to all sorts of weather, shipping containers come coated with some pretty toxic stuff—think lead-based paint—that has to be stripped off before they're inhabitable, and their plywood floors contain things like arsenic to keep pests away. "The average container eventually produces nearly a thousand pounds of hazardous waste before it can be used as a structure," ArchDaily notes. "All of this, coupled with the fossil fuels required to move the container into place with heavy machinery, contribute significantly to its ecological footprint." However unsexy, it's often greener and cheaper to just build a new wood-framed structure than to repurpose a container.

Housing aside, another proposed solution to the empty-container problem is the "gray box": Moving away from the current practice of companies owning, painting, and labeling their own containers, and toward a more fluid, coordinated system where everybody draws from a collective pool, the boxes reassigned as needed. Will this happen? Not immediately. Any comprehensive fix will be a heavy lift, trying to get all the shippers, regulators, et al. in sync, meaning you'll have to put up with the eyesore a while longer, I'm afraid. But hey, better in your front yard than banging into the Great Coral Reef, right? CW

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