not sell booze on board, or any other contraband that someone might like to consume? Yo ho ho!

Nightclub Splav Given that you’re already running an illegal bar, why not scale it up radically? Bring in a gypsy band, some techno DJs, or the fiercely popular “turbo-folk” ethnic divas! And — given that mere oil drums can only support so much dance floor — why not grab an entire dead barge or outdated river ferry, and just nail that hulk into place on the riverbank? You’ll have to settle that feat with the local cops somehow — but hey, cops are husky young guys; cops love boozy, miniskirted Belgrade party girls!

Deluxe Restaurant Splav Since everybody’s partying on the river anyway — life sure feels easier there, much less constrained somehow — why not feed them, too? The view of the Blue Danube is hard to beat, the air is cooler, ships have galleys — and if they don’t, you can always carve out a kitchen with a blowtorch.

Nouveau Riche Splav The urge to show up the neighbors is as old as mankind, so why not a big, gaudy, two-story splav with aluminum siding and maybe the tasteful stylings of a fake Chinese pagoda? Given that there are so many splavovi,

Splavovi are inexpensive houseboats that float along the Sava and Danube. This drydocked one still has the oil drums.

a host of handymen are in business making them, and they’re looking less spontaneous and more like a houseboat industry.

Over the past few years, Europe has been learning a lot about climate change. The summers are much hotter (that’s good for splavovi, because the river is cooler than anyplace else in town). The winters are milder (also good for splavovi, because they are flimsy, lightweight, and poorly insulated). The droughts are longer (not too bad, as splavovi can squat in the river mud if need be) and the rains are sharp, sudden, deep, and sometimes catastrophic. The flood of 2006 took a toll on splavovi.

So the trend is clear: both rivers’ shores will end up with huge, wet margins of uninsurable, semi-habitable, climate-change slums — the new urban river marshes. Such a severe situation will take a lot of painful adaptation. Unless you’re halfway there already.

A river isn’t a toy for city dwellers. A city is a toy for a river.

Bruce Sterling ( bruces@well.com) is a science fiction writer and part-time design professor.

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