How long might it take for swirling water to wear a hole in a standard copper water line? 3/4 inch, I think.

About 2 years ago, the City here had to drive through our front yard, crash down the fence (ground was frozen) and do extensive work on a mainline sewer pipe which had just been discovered to run through our back yard. Of course, the lawn hasn't recovered and new fence color is not a match for the old.

In the Spring the City came back to repair the curbside water shut off valve which they had discovered to be non-operational. They ripped out the curb, some of the street and lots of lawn. They dug down the 10-plus feet needed to repair the curb stop.

A week ago we had a water leak at the shut off valve area. Since turning off the valve stopped the flow of water, the City determined that the repair was our problem. Thanks to a storm drain only 3 feet away we avoided turning the neighborhood into a skating rink.

Our contractor moved all the snow (72 inches this year) and dug down and repaired the problem. Of course a pumper truck and much commotion were involved.

The problem! Our copper line was kinked, ie, squashed nearly by half in one place and had some pretty good dents in a few others. All this just inches from the curb stop that the city had repaired. A kinked line causes the water to swirl rather than flow smoothly and the pencil-lead size hole that occured was caused by this swirling water. A vortex.

I contend that they did this damage when they were working on their side of the line. Now I need to file a claim and get the City to pay for the repairs, well over $5,000 and then more for complete rebuilding of the front lawn.

Yes, I saved the pipe and no, I am not letting them "hold it".

Can you give me any advise or suggest information I could include with the claim?

Well, the physical evidence should remedy this situation but it seems that this is a case that should be resolved by your insurance company with the city. Your homeowners insurance should cover this type of situation, no? If so, they are much better situated to get it resolved with the city than you. They very likely have local adjusters that will come out and take the information they need. What would typically happen (from my experience as a contractor) is that the insurance company would pay your claim but then file suit against the city or your contractor.

If you have to self-file the claim with the city then you should take the photographs of the damage and the description by the contractor of what they found.

The contractor that originally did the work should have an interest in helping you resolve this because as the city currently stands it was their work that was defective.

Hopefully your insurance company will help with this because otherwise you might need.... a lawyer.

To answer your question - you need all the statements of the people involved, you need records of all your expenses and any other documents - definitely the pipe needs to be kept, photographs of the work. To start I would go to the city and try to talk to someone about it. Sometimes... emphasize sometimes, local officials can be reasonable.

Thanks ami. I am planning on leaving the insurance company out of the deal if possible. Insurance companies are not very pliable about now, what with the settlements of Katrina in Mississippi and all the ice storm damage. The average time between claims is suppposedly about 13 years. This house hasn't been covered by them that long.

The original work, about 2 years ago, was done by the City, not a contractor. This week's work was done by the most reliable contractor in town and he is willing to speak for us. The City here is quite open to negotiations. I just wanted any little bit of additional facts I could round up. I guess I will get started with the paperwork tomorrow.

I would imagine that swirl boring of a copper pipe of any thickness would depend on the amount of water over a period of time and how fast the erosive 'swirl' is. Along with the the amount of bend or kink plus the condition or quality of the material (copper pipe).

This: http://www.eng-tips.com/viewthread.cfm?qid=16852 has a lot of interesting discussion in it. Mind the pop-over ad thingy.

Um what grabbed my eye was the 8 feb 02 post by wktaylor:

quote:

I investigated copper water-pipe "corrosion" problems [2-5 yr old typical] in an overseas Air Base Apartment complex. The pipe "pin-holed" within a couple of years of installation... and outer-bends in the pipes and elbows were especially vulnerable! We uncovered some interesting factors:

Which I think comes close to the time frame you speak of.

A lab test of the pipe would pin-point time of erosion of the material (grade of copper) plus how bent/constricted plus the average water flow.

Thanks David. This is really helpful.