http://news.sciencemag.org/earth/2013/10/live-chat-saving-earth%E2%80%99s-water-supply
The Science magazine website says this chat will be archived.
More info:
Join biogeochemist Emily Bernhardt of Duke University and environmental engineer David Cwiertny of the University of Iowa on Thursday, 17 October, at 3 p.m. EDT on this page for a live video chat where we address these questions and take yours. Be sure to leave your queries for our guests in the comment box below.