I have been enjoying a good service of the system I installed in 2006 using essentially the same technique Brandon shared with us in his classic article. No major issues, that is, until now.

Yesterday, I noticed a significant reduction of pressure in one zone, and subsequently identified a leak in the pipe route. I dug out that section, and was really shocked to see that severe cossion has been going on. Within a length of about a foot, there were 3 holes, each approximately 1 millimeter in diameter. There were also other marks of corrosion on the outer wall of the pipe, but most of them have not corroded all the way through yet, except for the 3 holes. I went to google for the corrosion resistnce of the PVC, and found no clue.

This section of pipe is at the edge of the lawn, adjacent to an asphaltic driveway. It also happened to be in a spot where the snow would pile up everytime I had to shovel the snow off the driveway. And I do get quite a bit of snow here in Connecticut.

I started to wonder about two possible causes for the corrosion: (1) perhaps the chemicals from the asphalt is corrosive to the PVC, and (2) perhaps the de-icing salt that I sometimes put on the driveway had pile up together with the snow and leached down into the soil around the PVC pipe, causing it to corrode. Before now, I always thougth that PVC is resistant to all of these chemicals. But obviously not … Or, could it be some kind of insects in the soil that had been nibbling on the pipe? Bizare indeed!

I hope this is a localized problem … coz if not, the whole system I put in at the expense of a ton of sweat could be in an advanced stage of deteriation leading to a complete failure!

Can anybody share some knowledge on this aspect? It will be greatly appreciated, for obvious reasons! And I suppose all of you out there reading this would be interested to know too!