Now if you are in a housing developement that is prone to pinhole leaks like I am.The best thing to do is either have plumbing replaced or call Ace Duraflo,look up on internet.We had many leaks over the years destroying ceiling where they happened.We finally got tired of it and called in ace .What they do is set up their machine(outside compressor) and blow a abrasive thru the pipes then when that is done they blow a epoxy that coats the inside of the pipes and prevents further leaks.We chose that method because of the time it takes and the lesser amount of damage to the house.Only takes 2 days.Then they have gen contractors that repair any of the holes they needed to make,as part of the job.
I don't know what it is about the water in your area, but it tears up copper pipes. My brother in law lives in Vienna and had numerous major leaks that did considerable damage. He ended up making so many insurance claims that he was cancelled by his insurance company and had one heck of a time finding anyone that would insure the house. The only insurance he could get excluded all claims from water damage for a period of time that I think was five years. The newspapers have done numerous stories on the problems with corroded pipes in the area around DC. I will mention to him the solution you found.