Local government officials are flipping their lids. Manhole covers--as well as other metal fixtures including parking meters and guardrails-- are disappearing from city streets at alarming rates. The reason is the rise in demand for scrap steel and aluminum, driven largely by a construction boom overseas.

China now represents about a third of the global steel market and accounts for virtually all of the growth in demand. And that growth is enormous. As a result, scrap steel prices have quadrupled over the past few years. Several U.S. cities have seen a hundred or more of their manholes stripped bare.

Public works officials are frustrated by the trend, noting that it costs them up to $100 to replace each manhole cover, while thieves are lucky to make even a few dollars from each sale. But that's proven to be enough of an incentive for drug addicts or others who are desperate for cash.

What's especially worrisome, says Bob Ellinger, sewer maintenance manager for Columbus, Ohio, is not just the replacement costs but the danger posed by "dark spots" that people or cyclists could easily fall into. It used to be that Columbus saw just a couple of covers go missing in a year--usually after an especially good party weekend at Ohio State University--but during one recent month alone, the city lost 46 storm water grates and sewer drain covers.

About 150 manhole covers also have gone missing in Chicago, while Pittsburgh has lost about 400 parking meters. John Cichowski, a columnist with the Record in Bergen County, New Jersey, has made something of a crusade out of the fact that 12,000 linear feet of heavy-duty aluminum guardrails have been ripped off from the sides of Paterson-area highways. The replacement cost is "just a drop in the bucket," he writes, "until it's our car that's dropping over an embankment because some drug addict recognized a different kind of value."

The problem gets far worse the closer you get to the source of the demand. Some 5,000 covers have been stolen in Shanghai since the beginning of 2004, with even more taken from the streets of Beijing and Calcutta. In both China and India, officials are experimenting with non-metal materials, but apparently even concrete models are being stolen by thieves eager to get at the metal framing rods.

Theft shouldn't be such a problem, say spokesmen for the recycling industry, because a licensed scrap dealer won't touch, say, a huge metal disk that has the city name clearly stamped on it. "If people are stealing them, they may be pawning them off as antiques," says David Krohne, of the Institute of Scrap Recycling Industries, "but no reputable dealer is going to touch them."

But not every dealer, of course, is so upstanding. Hundreds of manhole covers aren't suddenly disappearing because of a boom in the antiquities markets. There's clearly money to be made in metal, so scrap will find ready, if sometimes shady, buyers as it changes hands numerous times on its way from Columbus to China.

That's why city officials in many places are working with local media to publicize the problem. In Akron, public works staff met with reporters from all the local newspapers and broadcast outlets. "We feel that all the press that we got scared the people off," says Jim Hewitt, a sewer maintenance superintendent. "The problem has pretty much gone away."

Media coverage undoubtedly helped, but probably a bigger factor was a police sting that nabbed two men, including a metal dealer who wasn't keeping required records of transactions and had in his yard a couple dozen city water meters, believed to have been stolen from vacant houses.

In most such cases, thieves are forced to pay restitution and may receive probation. Given the extent of the problem, however, perhaps some judges will revive the sort of sentence that Paul Newman received in "Cool Hand Luke" for decapitating two rows of parking meters: a couple of years on a chain gang. That's assuming, of course, the steel links haven't been sold for scrap.