EL NINO STORMS BLAMED FOR ERODING COASTAL BLUFFS.

Byline: Associated Press 

Slowly but surely, rain and waves are eating away at the California coast, and this winter's El Nino storms are speeding up the shoreline's eastward retreat, geologists say.

The good news is that, come summer, the sand will return to most beaches scoured down to bare rock by storm-driven surf.

But the news is bad for the many Californians who have built homes atop bluffs to enjoy the spectacular Pacific Ocean view.

``Beaches come and go, and usually they return,'' said Monty Hampton of the U.S. Geological Survey in Menlo Park. ``But when you erode the cliffs, they're gone forever. And it would be difficult if not impossible to engineer against that.''

A recent study by researchers at the University of California, Santa Cruz, found the coastline retreating an average of four inches a year - and that can accelerate to 5 or 10 feet during an El Nino year, Hampton said.

Stunned residents from Humboldt County in the north to San Diego in the south are learning California's geology lessons the hard way as soaking rain combines with the surf to erode coastal cliffs.

On Sunday, 50 homeowners from the Big Lagoon area of Trinidad on the north coast - where 11 cliff-top houses are in danger of sliding into the ocean - met to issue a plea for help. Rita Lakin fled her home after watching a 50-foot stretch of her yard drop into the ocean, and others fear their property will follow.

``The Big Lagoon homeowners are at a loss to know what to do,'' the group said in a statement.

South of San Francisco in Pacifica, television cameras have shown the world the inexorable collapse of a stretch of bluff under nine evacuated homes.

With tears in her eyes, Sylvia DeWitt left one of those homes while city emergency workers sawed off a room in a last-ditch effort to save the rest of the house.

``You can't understand how it feels,'' she said, fighting back sobs.

In Del Mar, just north of San Diego, an El Nino-fueled storm and a rising tide claimed two coastal luxury homes last week.

Southern California may have more bad news ahead, Hampton warns.

For most of the coast, sand washed off the beaches by waves usually is deposited in sand bars just offshore, and when the storms relent smaller waves carry it right back to shore in a matter of months.

But off the Southern California coastline lie deep underwater canyons.

``If it gets into one of these canyons, it's gone forever,'' Hampton said.

Only recently have geologists begun to map the eastward movement of the California coast, relying mostly on old sea charts and century-old photographs.

USGS geologist Dave Richmond is conducting an intense study of the Santa Cruz coastline.

``We're looking at these natural processes that have been operating at the present sea level for 6,000 years,'' Richmond said. ``Where they become a hazard is when you build homes or roads here.''

One example of a documented change is Ano Nuevo State Reserve, a coastal park north of Santa Cruz famous for its elephant seal tours.

Ano Nuevo used to be a triangular point of land, according to centuries-old charts. But erosion took away the land behind the point, creating an island where the seals now flourish.