A Tesla Battery Plant in Tucson? Show me the water!

If you saw the recent news about Tesla Motors, you'll know they're considering locations for a new mega-plant for lithium-ion batteries somewhere in the US Southwest. It looks like Tucson, Arizona is a candidate!

This prospect is definitely a mixture of pros and cons. Tucson would obviously benefit economically from the construction and operation of a facility like this one. I also mostly trust Tesla and the quite progressive City of Tucson to approach the project in an environmentally responsible manner.

My main concern is the water. Electronics manufacturing is a notoriously thirsty business, and worse, the water has to be insanely super-pure, with absolutely no trace impurities. At some electronics plants, that means using water otherwise slated for drinking water -- and in the deserts of Arizona, that is a very precious commodity indeed.

This certainly can be done sustainably -- Intel operates a large plant near Phoenix, and returns 60-90% of its water to the aquifer, purified. But it's not cheap. The equipment may run to the hundreds of millions, plus operating costs, so a relatively young company like Tesla may have to think very hard about whether they're capable of committing to protecting Tucson's water resources. Given their raison d'etre, it seems like the sort of thing they would want to do -- but until there are very detailed plans on paper, I hope the City of Tucson proceeds with a reasonable amount of caution.