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.
