|Index & Notes|
Other SeeSnake run north east of Multiple Time Clusters
Going a few more blocks north and several blocks east, you can see the other nearby SeeSnake run, also on the same kind of main - and this one we saved with anode retrofit. Recalling that the green dots are very shallow pits - the main had been there for 70 years and most of the pits went barely 20% in - we knew that th nine breaks it had suffered - three more than the other SeeSnake'd main we'd just replaced - were just about all the break it had in it! They'd already popped, except this bunch of red dots down here may still stage a break or two - but we can take that, better than we can take four hundred thousand dollars of replacement to avoid two breaks. So we retrofitted in 2013.
I'm afraid this does show how my little chart of cluster rules of thumb is still pretty lame, compared to having inspection data. It's a set of rules for guessing the future from the gross effects of defects; but the inspection data gives you the defects themselves, removing most of the guessing.
© Roy Brander, P.Eng 2016