The map now began to fluctuate in a way that at first was visually jarring and difficult to follow. But as time went by Saskia understood that this was a collage that someone had assembled from aerial imagery. It was a mixture of satellite and drone photography showing the “reservoir” and its environs as they had actually looked over the last few decades. Early on, the coverage was spotty—they only had images at intervals of weeks or months, so the change from one to the next was jarring—but soon enough （as years went by and satellite coverage became ubiquitous） it smoothed out to the point where you could watch it like a movie. And what the movie showed was the reservoir throbbing like a living thing, an organic blob under a biologist’s microscope. Sometimes it shrank to nothing and all you saw was trees. But then in the aftermath of a heavy rain it would form puddles in the low places that would grow explosively over a few hours or days to fill the neat boundaries circumscribed by the levees. Every so often it would break out and become an even larger body of water with houses projecting from its surface. As years went by, some of those houses disappeared. T.R. wanted them to notice that. He led the swarm toward the edge of one such neighborhood and let them see how a swath of homes had been lost to the floodwaters of Hurricane Harvey. “A hundred and twenty-five billion,” T.R. said. “That was the price tag for Harvey. Second only to Katrina, which was a hundred and sixty-one. So that’s what kind of money we’re talking. Damages on the order of one or two hundred billion, inflicted on this city suddenly and at unpredictable times.”
He ran the simulation forward over a couple of decades, then back, then forward again. Saskia sensed he must have his finger on a scroll bar in some UI, racking it up and down across the years. This made obvious something that might have gone unnoticed if they’d watched it more slowly, which was that the neighborhood
was moving vertically upward—actually gaining altitude, here and there, in fits and starts. More precisely, the level of the ground itself stayed the same but the houses were rising into the air, new foundations being slipped under them. “We see the rise of the house-jacking industry,” T.R. remarked. “Here are its fruits.”
And he shut off the AR visuals and took the flock on a slow flyby of a suburban street that was on the front line of the struggle against rising water. There were a number of vacant lots, currently sporting brown puddles of floodwater shaped like the floor plans of houses that had once stood there. All the houses that hadn’t been torn down were now standing proud of the water. Some were on high foundation walls of reinforced concrete, enclosing garages or storage space, currently filled with water but, it could be guessed, easy to hose out and dehumidify when the waters receded. Others—and these looked newer and nicer—stood above the water on reinforced concrete stilts, connected to the ground by ramps or stairs of welded aluminum.
“You can just imagine how expensive this is,” T.R. remarked, pausing the swarm for a moment so that they could look at a house that had been caught in the middle of the house-jacking process when the current round of flooding had struck. The contractors had left it high and dry on stacks of crisscrossed railroad ties and evacuated their equipment. An open skiff was bumping against its front porch on the end of a rope. A man came to the window of an upper bedroom, drawn by the noise of the drone swarm, and peered back at them. He was an ordinary-looking man in his fifties, shirtless in the heat, a strap angling across his pudgy torso from a long weapon slung across his back.
“Screwed” was T.R.’s verdict, “because thirty years ago, before Harvey, he bought a nice home here in this nice new development, and it all seemed like a great idea.” He took the swarm higher, effectively zooming out to remind them of just how many houses and neighborhoods were going through the same transition. “He did not understand—none of these people did—that this is stochastic land on the edge of a stochastic reservoir. They didn’t understand it because those are statistical concepts. People can’t
think statistically. People are hardwired to think in terms of narratives. This guy’s narrative was: the little missus and I want to settle down and raise a family, here’s a house we like in a neighborhood full of folks like us, they can’t all be wrong, let’s take out a thirty-year mortgage on this thing. And now he’s probably taking out a reverse mortgage or a HELOC to pay the house-jackers so he can have a prayer of being able to sell the thing. Multiply his story times all the houses you can see from here and you get an idea of what kind of money we’re talking. Now, we gotta recharge.”