The government's swine flu website went online today, and was promptly swamped with demand. This is not the first time such a thing has happened, but could it have been avoided?

The problem is that few systems can cope with huge spikes in traffic. The Department of Health says its swine flu site was set up to handle 4m hits an hour (96m hits a day). If the whole UK population visited the site over the course of a few days, there would not be any problem. But as it turned out, the site got 2,600 hits a second, or 9.3m hits an hour. It didn't actually crash, the department said, but BT — which is hosting the site — quadrupled the capacity by 5.30pm to maintain the service.

The problem of traffic spikes is not restricted to computers. If there's a crash that closes a busy motorway, hundreds of drivers reach for their mobile phones at the same time and the service can't cope. Electricity suppliers watch the TV schedules closely for probable spikes in demand when millions of people simultaneously get out of their seats to put the kettle on.In the computer world, there's a name for these spikes: it's called the Slashdot effect, after a "news for nerds" site. Someone posting a web address on Slashdot can send hundreds of thousands of people to a website at the same time, knocking it over. On Twitter, the same thing can happen when someone with a large following — such as Stephen Fry — posts a link.

There are, of course, ways to avoid the problem. But these require effort and forethought – and money. It's reasonable to ask whether the department did a good job of predicting demand. But whether it should behave like a commercial company webcasting, for example, a live show by Madonna at the taxpayer's expense is another matter.