Hydrogeologist on Edwards Aquifer

City of Austin hydrogeologist David Johns speaks about the karst features of the Edwards Aquifer at the Green City Festival on October 13, 2007 at Austin City Hall. Others at the festival at booths on the plaza talk about the work they do to protect the environment.

This episode is part of ICONMEDIA.ORG's Texas Water 101 series that appears on ICONMEDIA.ORG's Austin community television show Austin News Real.