Instructions for how to rebuild a beach:

Step 1: Remove houses.

Step 2: Add sand.

Step 3: Let nature take over.

That's the successful formula followed in Pacifica, which this summer celebrates the birth of a new shoreline and estuary on the edge of Pacifica State Beach, also known as Linda Mar Beach -- one of the most-loved summer playgrounds of the Bay Area.

Four acres of new beach replace the former site of two houses and and 100 tons of rubble. Two acres of wetlands thrive on what was once mud and dry land. Wild animals and plants are arriving. So are surfers, sun-bathers and other beach-lovers.

``We're working hand-in-hand with nature, not controlling nature,'' said Pacifica Mayor Jim Vreeland, a surfer and environmentalist who has made the project a major goal of his incumbency.

At a time when coastal property values are stratospheric, ``it's the opposite of most development trends,'' said Bernard Halloran of the Pacifica Land Trust, which worked with the town to purchase and restore the land.

``This is a wonderful and very rare instance when a piece of private property has been bought and restored back to its natural state,'' he said.

For decades, people tried to control this tiny stretch of coastline. To save two homes from flooding and erosion, artificial materials were poured onto the sand. San Pedro Creek was straightened, channeled and deepened.

But the solution was temporary. While sea walls, boulders, jetties and breakwaters may stop or slow erosion of a beach in the short term, they can accelerate erosion in the long term.

It was also messy, unsightly and hostile to wild plants and animals.

Frustrated, local beach-lovers stepped in. The Pacifica Land Trust, the city of Pacifica and the Coastal Conservancy raised money and bought the site in 2002 for $2.2 million.

The homes were torn down and hauled away. Concrete, rubble, asphalt, reinforcing steel and 250 tires were excavated. Utilities, phone cables and a high-voltage power line were rerouted.

Four thousand cubic yards of sand were delivered. Dunes were built. Grasses were planted. When the shoulders of the old channel were removed, the creek widened to create a new freshwater estuary.

It is part of a growing national trend to attempt a ``managed retreat'' on the coastlines, and structures are destroyed or moved rather than shielded with rock and concrete. In Capitola, two ocean-front houses were moved from Depot Hill; in Humboldt County, a house was moved from Big Lagoon.

The result is nothing short of a transformation.

Pacifica State Beach, which has had a thriving surf scene since the '40s, is now larger, safer and cleaner.

``Before, there was a lot of concrete riprap, which was hard to walk on and not very aesthetically pleasing. It created an artificial sea wall,'' said surfer Karen Cochran of the Pedro Point Surf Club. ``Now the beach is back to its original natural state.''

And San Pedro Creek, no longer channeled, is free to wander and collect in shallow pools.

Its water nourishes plants and animals. Wild grasses have taken root, offering cover. Great blue herons and other birds hunt for food in its quiet waters. Steelhead trout and the endangered red-legged frog are offered a better home.

The site is still young and growing. But its future looks bright.