Freshwater in California’s San Joaquin Valley is on the brink of disappearing. While Governor Jerry Brown’s proposal for a peripheral canal is reigniting centuries-old battles over water rights, environmentalists and billionaires are all vying for control over California’s water supply.

In the final episode of our three-part series, Emerson Rosenthal gets his inner Erin Brockovich on as he investigates a water war that could potentially destroy access to drinking water for millions of people. Welcome to California, ground zero of America’s water crisis.