This week, Governor Jerry Brown’s controversial water project is back in the public eye. State officials are launching a marathon series of hearings for the “twin tunnels,” as they’re known, that will ultimately decide the fate of the project. What are the Delta water tunnels? They’re two, 30-mile water tunnels that would be built in the Sacramento-San Joaquin Delta, east of the San Francisco Bay Area. Each tunnel would be 40 feet in diameter, larger than the tunnels that carry BART trains under San Francisco Bay. The project, dubbed “California WaterFix,” would be buried 150 feet below ground.