Digital Sewer Inspection

Last week, I was at the offices of a city’s sewer inspection team. I heard one of the employees say, “We are only allowed to use digital sewer inspection.”

“But how do you prove that it’s digital?” I asked.

“It’s on DVD,” he explained. “How could it not be digital?”

Lots of municipalities have this same digital requirement. And digital technology is awesome. Before you learn about how great digital video inspection is, let me explain that some “digital” inspections are imposters.

Twenty years ago, you may have had an incredible collection of 33 rpm record albums. You can take those records today, and burn them onto CD’s. You an even make them into MP3s and load them onto your iPod. But you’ll still hear them hiss and crackle, because the originals were never digital. Burning them to a digital medium doesn’t make the sound better.

You can make a photocopy of a photocopy of a photocopy of an original, and then scan that third generation copy to your computer. It’s in bits and bytes — digital, right? Well, not really. Digital doesn’t degrade no matter how many times you copy it, but analog – those paper photocopies — got fuzzier and fuzzier each time. Your computer “digital” version will be just as fuzzy as the final photocopied version.

So when you tell your boss that you met the city’s requirements and produced a digital sewer inspection, be sure that it is not a digital imposter — an analog CCTV signal that was sent 2000 feet to a truck with the fanciest of electronics. No matter what you do to that analog CCTV tape, it will always be analog.

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