Something I learned from fixing things

Sewer Repair
Your savings? They are gone now.

Recently our sewer pipe broke, and it’s going to cost us 10 grand to fix it. Our yard is a mess with an excavation eight feet deep and 80 feet in length. But that isn’t the important thing.

The important thing is that in the last 5 years, most of the houses on the block have had to have this repair done. All the houses were built about 50 years ago. Buried clay tile only lasts about 40 to 60 years.

If you build a lot of something, they will all start to break at about the same time.

I’ve spent a lifetime fixing things. Cars, bicycles, photographic equipment, computers, and more. When something breaks, people turn around and look at me. From this I’ve learned that systems and objects have a “service life”. That is, you can expect them to last about n years before they need repair or replacement. If you have 100 of them, and plot how long they worked until failing, a failure curve will emerge.  Most of them will fail at approximately n years and a few will fail before and after.

The big picture

Crude MTBF concept sketch
Crude MTBF concept sketch (click to embiggen)

If you build a bunch of houses, most of them will need new sewer pipes around the same time. The same goes for roofs, furnaces, sinks, etc. Each of these systems has a Mean Time Between Failure (MTBF) curve. When you look at that curve, you know about how long it takes the system in question to wear out or at least need maintenance.

Ideally, you should use this information to plan ahead. Because fixing them is gonna be real expensive.

This also applies, broadly, to roads, bridges, tunnels, train tracks, schools, water mains and sewers, and much more. Now suppose you cut way back on maintenance and replacement? What would the result be?

Right: the roads, bridges, pipes, and whatnot will all start failing at once. It’ll be like an invasion, with foreign saboteurs dynamiting your vital infrastructure. Only in this case, the saboteur is named “Entropy” and you were supposed to be staying ahead of him all along. It is doubtful that actual terrorists could do as much damage on as wide a scale.

But maybe you were distracted by fighting wars you didn’t need to fight, propping up financial firms that were too big to fail, and just generally pretending that Entropy didn’t exist. Eventually you won’t be able to deny it anymore, and by that time the economy will be suffering because the infrastructure that supports it will be in shambles. It didn’t take much foresight to know Entropy was coming. All our experience in everyday life tells us about him.  Our leaders would be morons to pretend otherwise, and we’d be morons to keep voting for them.

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