Water? In MY upper mantle?

[Rynn]

Interesting. How might this excess water be bright to the surface for use? (I'm thinking some of this could be transferred off Earth to Space Colonies, specifically)

That is really unlikely to be a good, or viable, idea. Firstly because the gravity well of Earth means that it will take a ridiculous amount of energy to get a significant amount of water off of it. Far easier (and still a daunting tasks) to redirect water comets. Secondly I doubt that sucking out subterranean water in substantial amounts wouldn't have any effect on tectonic stability. There would likely be very undesirable side effects.