I have seen books from the 1920s that recommended chemicals you could add to your water to prevent the water from eroding the lead. Water is a great solvent for almost anything, and so if you are not careful water will pick up whatever is in the pipes.

I'm not going to look up those chemicals - I doubt that they would pass modern safety standards. If you maintain a water supply that has lead anywhere you should figure out what modern chemicals to use to prevent lead (or whatever your pipes are made of) from being eroded. I hope the people who maintain water supplies already know about this though.