SAN FRANCISCO (KPIX 5) — It appears California has come out of the drought, with a fury.

Atmospheric rivers, more commonly known as Pineapple Express storms, fueled by Hawaiian tropical waters, have pounded the Bay Area, and the state, with rain.

But this is not new. Over 100 years ago California was in the same boat, literally. The rain started to fall just before Christmas, and it didn’t let up for over 40 days. The Central Valley became a lake.

It was 1862. Leland Stanford was sworn in as California’s 8th governor. But he wouldn’t start his term in Sacramento because California’s capitol city, along with much of the state, was ten feet under water.

Geography Professor and Berkeley Researcher Dr. Lynn Ingram described the flood as ‘a major catastrophe.”

“You couldn’t walk around the streets. It was just people scrambling with row boats and little houses floating away and furniture and cows,” explained Ingram. “[Atmospheric rivers] can carry up to ten Mississippi rivers worth of water vapor from the tropics. It’s like a fire hose.”

So the question is, could it happen again? The answer: yes.

Geographic data indicates California has a mega flood about every 100 to 200 years. So the Golden State is overdue, long overdue for a big storm.

In 2011, the USGS, along with other agencies, constructed its ‘ARkStorm’ model. It showed potential projected losses of over $700 billion.

Even more troubling is the possibility that 25 percent of all structures in the state could be comprised. Millions of residents could lose their homes.

It is a possibility that Ecologist John Bourgeois knows much about. Bourgeois, the executive project manager of the South Bay Pond Restoration Project is also a Louisiana native, so he has seen firsthand what mass water damage can do to a region.

Coastal flooding can easily damage outdated levee system and safe travel, even clean drinking water quickly becomes a distant memory. Bourgeois says awareness and planning have been the key focus of his agency, and others, statewide.

“Being from Louisiana I know personally how much New Orleans has changed since Katrina because people have left and it has come back, but it’s not exactly the same and we do risk that here in Silicon Valley. If you look at what is at risk here, it’s not just the infrastructure, it’s also our high tech businesses,” explained Bourgeois. “In the SF Bay Area there are over 350,000 people that live in the 100 year flood plain. And I am sure the vast majority of them don’t realize that they are living in an area that is at risk.”