The Brown administration’s plan to dig giant water tunnels under the Delta looks financially precarious, like a bus hanging out over a cliff. It’s economic benefits have been seriously challenged and there is no agreement yet whether the people who stand to profit are willing to pay for it. State water contractors in the San Joaquin Valley and southern California who want this pricey project, called the Bay Delta Conservation Plan or BDCP, are promising economic benefits based on a supposed threat that, without the tunnels, future water exports will plummet.
A central problem for tunnel promoters is that if their predictions are wrong about sinking water exports – if future water deliveries through existing Delta channels continue as they are today, and especially if they improve, the economic value of the tunnels would evaporate. Several sources consulted for this report believe that water exports could be improved in the near future, with new fish screens that are in current testing, plus some modifications of through-Delta channels. That, combined with new storage south of the Delta to take excess water in wet years, could either make tunnels unnecessary or reduce their size.
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