"SACRAMENTO, Calif. — Most of the salmon caught in California come from hatcheries in the Sacramento Valley, yet it turns out not much is known about these fish even though they are bred by hand."

"Investigators were looking at how a small, seemingly insignificant leak at one of the country's biggest oil refineries quickly unraveled into an intense fire that sent acrid black smoke into the sky and hundreds of people to hospitals with health complaints."

"Thousands of East Bay residents were ordered to stay in their homes with the windows and doors closed Monday night after a series of explosions and fires tore through Chevron's Richmond refinery."

"State and federal leaders on Wednesday reaffirmed their commitment to build a giant pair of tunnels to divert the Sacramento River out of the Delta."

"Damage done to wildlife and the environment by illegal marijuana growers is causing great concern, especially for officials with the state Department of Fish and Game."

"FRESNO, Calif. — California Gov. Jerry Brown is set to reignite the state's water wars when he makes the long-awaited announcement next week about plans to build a massive twin tunnel system to carry water from the Sacramento-San Joaquin River Delta to farmland and cities."

"CALEXICO, CALIF. — As the relentless wind stirs up piles of dust and dirt and creates a gigantic funnel of haze in the vast, sweltering Imperial Valley, children like Marco Cisneros battle to breathe."

"Pacific Gas and Electric Co. suggested to managers before the San Bruno pipeline explosion that downgrading more than 2,300 natural-gas leaks - and potentially not fixing them - would save the company nearly $5 million, according to an internal document obtained by The Chronicle."

"LOS ANGELES -- US nuclear regulators published an update on California's troubled San Onofre power plant Thursday, sparking an expert warning that the problem is more serious than first thought."

"LOS ANGELES - The future of the troubled San Onofre nuclear power plant could balance on an inescapable question: Is it worth the money to fix it?"