Water Always Wins

In 2005, one of Weissmann’s grad students, Amy Lansdale Kephart, went through ten thousand well logs and discovered another paleo valley near Modesto. She built a 3-D map with the data and modeled how water would flow through it and how useful it could be for water storage. The Modesto paleo valley is about 0.4 to 1 mile wide and 10 to 98 feet thick. She found it could influence groundwater flow, attracting water into it or pushing water out of it, for around 12.4 miles on either side of the valley and for hundreds of feet in depth. A student of Fogg’s, Casey Meirovitz, found a third paleo valley near Sacramento in 2017. Then, in 2019, Fogg’s student Steven Maples showed that it could accommodate almost sixty times more water than surrounding lands. “It’s a shame that we still don’t know where the rest of them are in California,” says Fogg in his mild way. “This should be a priority.”