California Coast & Ocean

These days he sits on his front porch looking at the grand, empty houses for sale around him. The possibility of a flood is only one of the spooks in his life. With the Central Valley property market having swung from boom to slump, as elsewhere, he has lost hope of a quick profit on his home.

"We were hoping to put our kids through college with the profit (from the house). It didn't turn out that way. These are a bunch of white elephants now," he laughed wryly.

Guinan said he had been aware the Delta was prone to flooding, but when it came to discussing the final details with the sales agent, the discussion went like this: "That's just one of those things. Don't worry, there's only a hundred pages to sign. Just sign this page and move along. That doesn't mean anything. Just keep signing. Sign your life away." Guinan laughed again, throwing his hands up. "I was aware of it. But life is a risk. It's like driving to the Bay Area every day. You take a risk."

He remembers seeing the giant 1997 flood in the Delta on television. More than 30 levees were breached after heavy winter rains and a substantial snowmelt in the Sierra. Thousands of acres of farmland and hundreds of homes were inundated, with the worst flooding along a 15-mile stretch of the San Joaquin River, north of where it intersects with Interstate Highway 5. Nine people died. But it was television, Guinan said. It didn't hit home that this could happen to him.

"It's foolish actually," he said. "I haven't seen the flood, only heard about it. If I'd seen it, I would be more apt to say, 'Forget it.' I wouldn't move out here."

Wanting to get into a new home as cheaply as possible, he didn't buy flood insurance. And because Mossdale is officially outside of the Delta flood-zone map, he is not required to. But that could change. The Federal Emergency Management Agency (FEMA) is redrawing the flood-zone map, which in some places is 25 years out of date. City and county officials are scrambling to provide proof that their levees meet the so-called federal 100-year standard. If they don't, the areas behind those levees will be brought within the official flood zone, and homeowners with federally backed mortgages (most mortgages are federally insured, by Freddie Mac or Fannie Mae) will be required by federal rules to buy flood insurance. At Mossdale Landing, the age of the levees and the new FEMA requirement for better-engineered levees casts doubt on the community's future.

The City of Lathrop, which approved the Mossdale development, is working on a submission to provide proof to FEMA that its levees are up to scratch. FEMA spokesman Frank Mansell said the agency expects to present local authorities with the preliminary version of an updated flood zone map this autumn.

Often home buyers who are told their homes are behind a levee built to a standard known as the "100-year levee" feel comforted, thinking the levee was built to withstand floods for at least a hundred years. In fact, the standard means that in any year there is a one-in-a-hundred chance of a flood big enough to breach the levee. FEMA described the 1997 flood as a "typical" 100-year flood, according to the Stockton Record. Re-envisioning the Delta says that taking into account all residual risks (such as the once-in-200- and once-in-300-year floods), there is a 26 percent chance that over the life of a 30-year mortgage a house protected by a 100-year levee will be inundated by a flood.