California officials Tuesday released a detailed environmental blueprint for Gov. Jerry Brown’s controversial Delta tunnels project, saying the $15.5 billion plan “minimizes potential effects” on endangered fish species whose populations have dwindled following decades of water pumping. The Department of Water Resources unveiled its so-called “biological assessment” for the proposed tunnels, which are designed to re-engineer the plumbing of the battered Sacramento-San Joaquin Delta in order to improve reliability of water deliveries to the San Joaquin Valley and Southern California.