March 21, 2013 – CALIFORNIA– Overnight, a sinkhole swallowed a pond on Mark Korb’s property in Newcastle, Calif. When he went to bed Saturday night, the pond was there. On Sunday, March 17 it was gone. How does that happen? While northern California is nowhere near as prone to sinkholes as Florida (see USGS sinkhole map), one clue might be the fact that the pond was man-made. While sinkholes don’t need a human trigger; changes in drainage due to construction or agricultural irrigation have been known to activate mass outbreaks of sinkholes in Florida, and other parts of the country. As The Christian Science Monitor reported earlier this month after a Florida man was swallowed in his bed by a sinkhole, “Drought followed by heavy rains can also instigate sinkholes as heavy, water-logged earth presses down on limestone caves suddenly devoid of buoyant water. The two previous deaths attributed…