Does copper rust in the presence of water?

No. In the olden days wooden ships were coated with copper metal to prevent wood borers and increase speed.

Well, if copper rusted in the presence of water, we'd have some seriously colorful plumbing! But no, copper doesn't rust. Instead, it likes to get its groove on and develops a lovely greenish patina called copper oxide. So, while it may not rust, copper certainly knows how to accessorize!