Water. Under its browning hills and suburban pavements, Fremont bubbles with water. Few know the story as well as Joyce Blueford, who has just helped bring a creek back to life.

Blueford's creek is Mission Creek. It rises from a spring on Mount Allison, meanders through the Mission San Jose district and feeds Lake Elizabeth in Central Park. Flowing year-round, it signifies the role water has played in every phase of the natural and human history of the southeastern slopes of the East Bay.

Water is the unbroken link from the giant animals of the Ice Age, which left one of the richest fossil beds in California in the gravel beds under what is now Interstate 680, to the Ohlone, the Spanish, the Mexicans, the farms and towns that followed the Gold Rush, and finally the urban consumers who rely on dams hidden in the hills.

Blueford has played a part in restoring just a small piece of what once was a network of a dozen creeks flowing from Mission Peak toward the bay. The healed portion of Mission Creek runs only a half-mile -- from Driscoll Boulevard to Palm Avenue behind Hopkins Middle School and Mission San Jose High School.

But for Blueford, a sedimentary geologist and science educator, the microcosm opens up large possibilities for residents to experience the environment as it was before development transformed it by covering it up, cutting it into pieces, diverting it into channels and sometimes just blocking it behind fences.

"Our bureaucracy doesn't make us see how important water is -- they kind of hide it," Blueford said.

Looking at a map or taking a drive around Fremont, it takes some effort to find nature's pulse under the suburban flatness. What trails, streams and wetlands exist tend to be sliced by the city's grid. This is by design, for taming streams to make it safe for people to build houses has been part of the reality of Fremont since the city was incorporated. Fremont was to be the ultimate planned city.

"There was a gigantic flood in the '50s, just before incorporation," said Bob Wieckowski, board chairman at the Tri-City Ecology Center, an environmental group in southern Alameda County. "Huge floods -- Mission Creek overflowed, Alameda Creek overflowed, Coyote Creek. Eisenhower was president. The Army Corps of Engineers had lots of money.

"How are we going to solve this problem? Cement it -- cement everything. "

The restored portion of Mission Creek puts the riparian environment in full view for the first time since the creek system was turned into a ditch system.

On Saturday, the groups involved in the restoration will celebrate the project with an open house. Exhibits on the path along the creek will tell the story of the cleanup and the creek's rebounding ecosystem. The restoration was a joint effort by Blueford's group, the nonprofit Math/Science Nucleus, along with the Alameda County Flood Control and Water Conservation District, the City of Fremont, the Union Sanitary District, the Fremont Unified School District, Tri-City Ecology and the Mission San Jose High Green Club.

The project cost $1.4 million. The state Department of Water Resources provided the funding, along with the city and the flood-control and sanitary districts.

Fremont is a city of more than 200,000 with a strong stance toward economic development. Blueford sees the project as a demonstration of residents' growing sensitivity toward the environment.

"I think a lot of people are getting sick of this pro-growth, pro-growth, " she said. "There's no place else to grow."

Wieckowski said he hopes the project will inspire a push to restore creeks throughout the city. He said the city government could take the next step by identifying sites for trails and wetlands rehabilitation, then taking their ideas to the county agencies that control the creek system.

"Fremont's done a wonderful job protecting the hills," he said. "I want to take our waterways and make them a vibrant part of our city."

The main task of the restoration was to realign the stream from a flood- control channel to a natural meander. Decades of heavy rains had gouged the bed. Plus, a sewage pipeline was dangerously exposed, and a 10-foot waterfall created a hazard for kids playing in the creek.

Animal, bird and insect life couldn't get a foothold because the stream lacked protected pools. Eucalyptus trees introduced by pioneers hogged space that normally would be filled with native trees like oaks and sycamores.

Engineers slowed the stream by creating terraces and protected the banks by placing logs made of coconut-husk fibers and root structures of previously cut trees.

Of the 160 eucalyptus trees in the stream, 60 were removed, and the clearing created a flood plain terrace, which today blooms with newly seeded native flowers like lupine, clover and California poppy. Native trees and shrubs had been planted in the new meadow, which in time will resemble the familiar multistoried environment of any unmolested stream in the Bay Area: oaks above, willows below.

The restoration site ends at Palm Avenue, where access to the stream is blocked by a fence. The fence keeps hikers and bikers away from the backyards of pricey neighborhood homes. Dominated by oaks, the stream bed beyond the fence looks unchanged by development. Parts of the environment are much older than the homes surrounding it: one oak is 300 years old, predating the founding of Mission San Jose upstream by about 100 years.

Blueford compared the oak-shaded spot to the restoration area. "This is what this looked like in the '50s," she said as she looked through the fence. "They wiped out the oaks -- ridiculous."

By rights, the 100 remaining eucalyptus should have been taken out to make way for more native species. They not only crowd out native plants but also drive them away with chemicals they emit. But some remain as a concession to a people-engineered environment. The tall trees provide a screen for nearby homes. They also serve as roosts for some 200 turkey vultures, which have been displaced from upstream areas by development in the hills.

"We as a group decided that eucalyptus aren't bad, especially when we learned that turkey vultures didn't have a place to go," Blueford said. "We felt we owed it to them."

Other forms of wildlife are discovering the stream. "We counted 10 nesting pairs of mallards," Blueford said.

The creek itself is reasonably healthy, according to a chemical analysis by members of the Mission San Jose High Green Club. It appears to be in condition for a full restoration in 10 to 15 years, when the native trees are re-established.

"Hopefully, we'll get back to the natural, native environment," said Norman Howell, the club's adviser.

A page on Blueford's Web site -- www.msnucleus.org/watersheds/index.html -- tells the story of the restoration and details the watershed's geology and natural history. The site features lesson plans designed for students in first and second grades. It describes every animal, plant and microorganism found in the creek.

The site includes an animated story, "Through a Frog's Eyes," written by Mission San Jose High students April Yang and Frances Kwong. The story imagines the restoration as told by an amphibian named Little Pacifica Frog.

Little Pacifica questions her grandma on how the creek was changed so that it was no longer the healthiest place for animals.

The grandma explains as human figures stride across green lawns:

"Many suns ago, there appeared some colorful giants. They built homes and grew orchards. They didn't think about the creek critters and what we needed to survive. Many creek critters left for wetter areas.

"The giants' selfish use of the water and paving of the ground with concrete and asphalt caused erosion."

People came to Mission Creek long before there were freeways and subdivisions. They came for the same reason animals did: it was a choice spot.

For the Ohlone, the creek was a waterway from the bay to their village in the foothills, called Oroysom. It was also a place to hunt and drink.

In 1776, Anza, the explorer of Alta California, camped nearby at what is now Alameda Creek and noted its deep pools and groves of sycamores, cottonwoods and oaks. About 20 years later, Spanish explorers looking for a place for a new mission noted the "perennial stream through the land" and were impressed that the Ohlone had built a reservoir.

In 1797, the Spanish built their mission, one of the richest in the chain. Free-flowing streams watered their livestock and supported crops and orchards. Warm water came from nearby Warm Springs, a source that seismic action later squeezed dry.

After America's military defeat of Mexico and the Gold Rush, the pioneers moved in, among them explorer John C. Fremont.

The Mission San Jose Water Co. began selling water to Oakland and San Francisco in 1878. Juan Gallegos built a huge winery, using the water to irrigate miles of vines. Railroad tycoon Leland Stanford had a fancy home with mud baths.

The pioneers built towns and farms to grow food for San Francisco. The valley was much like the Salinas Valley is today, but only one produce farm remains in Fremont.

In the history of Fremont, rocks and water go together. As a geologist and a science teacher, Blueford can tell both sides of the story.

In the Pleistocene era, 1.3 million years ago, water that seeped from the twisted layers of sandstone forming the hills supported an Africa-like ecosystem dominated by large vertebrates, such as horses, sloths, camels, sabertooth cats, wolves and a four-pronged antelope. There were fowl, a musk ox-like animal, a giant mouse and a 14-foot-tall bear named after Fremont's Irvington district. Fossils have been found as young as 11,500 years old.

From 1944 to the 1950s, paleontologists removed more than 150,000 pieces from the fossil beds known as the Irvington Gravels. The state later built I- 680 over the gravel pit that yielded the fossils, a quarter-mile south of the intersection of Osgood Road and Washington Boulevard. The occasional fossil fragment gets loosened by floods.

"No doubt, there are washings that come down from the creeks," said Phil E. Gordon, a retired teacher and son of the late paleontologist Wesley Gordon. "I have heard rumors that there are some pieces of bone that somehow end up in science classrooms."

He said 54 animals were described in the Irvington beds. The theory is that the heart of the environment was a river that flowed from where Hollister is today and emptied into the ocean near the Farallones. The bay was a plain and the Golden Gate a canyon.

"That river came through and had some extensive backwashes where floating dead animals would get caught in slower water," Gordon said.

Geological changes gradually pushed the river north and the giant mammals could no longer survive in the East Bay.

Where to go

The Mission Creek restoration celebration is 9:30 a.m.-3:30 p.m. Saturday at Mission Creek trail between Palm Avenue and Driscoll Boulevard. (510) 790- 6284; www.msnuceus.org.