Sarah Goldhagen taught architectural history and theory for 10 years at Harvard. She and her husband are now raising two kids in Newton. She writes at home. She's done a classic book on the great architect Louis Kahn, and she's working on another that will try to define, once and for all, the nature of modernism.

At the moment, though, she's obsessed with a less exciting kind of architecture.

Her interest is infrastructure.

Yes, the very word puts people to sleep.
But wait. Goldhagen says to think of it as a detective story.

A bridge collapses in Minnesota. A steam pipe explodes in New York. Water in some cities is found to contain lead. A utility line blows here in Boston. A beam cracks under the Tobin Bridge. Lower Beacon Hill and Back Bay houses are at risk of sinking. Schools have boarded-up windows but don't have books.

It's like an Agatha Christie mystery. Slowly, the detective begins to realize that maybe, just maybe, all these scattered events are linked. There's a pattern here. A common criminal.

Our infrastructure isn't the work of a criminal, but it's a kind of crime. Much of it is a disaster waiting to happen, or already happening. "These are not discrete events," says Goldhagen.

What, exactly, is infrastructure? For Goldhagen, it's everything we build that is meant to serve the public: highways, streets, bridges, tunnels, sidewalks, transit systems, utilities of all kinds, parks, soccer fields, even public schools and colleges.

She says we need to think of it all as one integrated whole, and then ask who's taking care of it. No one, it turns out....