![Rich Pedroncelli FILE - A ship moves through the Sacramento-San Joaquin River Delta near Bethel Island, Calif., March 12, 2008. California Gov. Gavin Newsom's administration now says it will cost more than $20 billion to build a giant tunnel so the state can catch more water when it rains and store it to better prepare for longer droughts caused by climate change. (AP Photo/Rich Pedroncelli, File)](https://mapi.associatedpress.com/v2/items/4adff8842c584c3ea161e6b524d882f2/preview/preview.jpg?s=680x)
FILE - A ship moves through the Sacramento-San Joaquin River Delta near Bethel Island, Calif., March 12, 2008. California Gov. Gavin Newsom's administration now says it will cost more than $20 billion to build a giant tunnel so the state can catch more water when it rains and store it to better prepare for longer droughts caused by climate change. (AP Photo/Rich Pedroncelli, File)
![Rich Pedroncelli FILE – A sign opposing a plan to build a giant tunnel to ship water to Southern California is displayed near Freeport, California, May 2, 2016. California Gov. Gavin Newsom's administration now says it will cost more than $20 billion to build a giant tunnel so the state can catch more water when it rains and store it to better prepare for longer droughts caused by climate change. (AP Photo/Rich Pedroncelli, File)](https://mapi.associatedpress.com/v2/items/627fe67e55564c6d861978ff270bdc78/preview/preview.jpg?s=680x)
FILE – A sign opposing a plan to build a giant tunnel to ship water to Southern California is displayed near Freeport, California, May 2, 2016. California Gov. Gavin Newsom's administration now says it will cost more than $20 billion to build a giant tunnel so the state can catch more water when it rains and store it to better prepare for longer droughts caused by climate change. (AP Photo/Rich Pedroncelli, File)