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Four Boys Find Buried Teeth, Help Unravel Untold Tale

  • May 3, 2012

By Cindy Simons

Last month’s column was about the construction of Chabot Dam and Anthony Chabot, the “Water King” who created the Contra Costa Water Company. Stories of the rich and powerful are often recorded, but the history of laborers and the less powerful are often lost. Sometimes, a determined researcher uncovers those lost stories. This month’s column is about the Chinese laborers who built the dam, and some of the difficulties and tragedies resulting from its construction.

In 1963, four San Leandro boys—David and John Salsedo, Edmond Caldira, and Joe Sgroe—were hiking along San Leandro Creek below the dam. They came across bones, pottery, square nails, and teeth.

Unnerved, they found the park director and told him what they had seen. He escorted them back to the area, where they found more relics, a few of which they took home with them. They then wrote to the state archaeologist, who told them that the teeth were those of a pig, “As you know, the Chinese always ate pigs and still do,” he wrote back to them. The discovery was written up in the newspaper, but apparently didn’t attract much interest.

Fast forward almost two decades.

“Deep in the canyon carved by San Leandro Creek below Lake Chabot, a nineteenth-century Chinese labor camp lay buried and forgotten.  In June 1980, this sleeping, century-old camp awoke to the twentieth-century roar of earth-moving tractors.  The tractor drivers, contracted by the East Bay Municipal Utility District, scattered bowls, pots, and pipes as they rumbled through the old campsite to improve the dam’s spillway.”

This quote is from The Chinese Laborers of Lake Chabot: A History of Their Contributions to the Construction of Lake Chabot Dam, 1874-1892 by Jacqueline Beggs.

After retiring from the East Bay Regional Park District, she researched and wrote this fascinating history of the construction of the Lake Chabot dam. It was published by the Alameda County Historical Society in 2010.

A park ranger recognized the historical significance of these artifacts, and contacted California State University Hayward (CSU East Bay today).  Professor George Miller of the Anthropology Department also realized the significance. He registered the site and then organized an archaeological excavation of the Chinese labor camp.

He called the site Yema-Po, Chinese for “wild horse slope”. 

Why “wild horses”?

The earth-filled dam at San Leandro Creek was created with layers of compacted clay. Several hundred wild horses were tied together and driven back and forth over each foot layer of clay, compacting it into a hard wall.

The poor horses would become caked with clay. At first, they were driven through water to clean them off at the end of the day. But soon their hides were coming off with the clay, and the caking clay had to be left on the miserable animals.

Archaeological Excavation Reveals Life at the Dam Site

The artifacts found in Miller’s archaeological dig provided clues about the life of laborers who had been all but forgotten.

Work began on the dam in 1874; by 1875 there were 500 Chinese men living in a camp by the creek below the dam site, and 100 white men living on the hilltop, where there was also a stable for 180 horses and mules, a wheelwright shop where carts were made, a blacksmith shop, and offices.

Miller and his students uncovered more than 60,000 artifacts in the area of the Chinese camp, where at the peak of construction as many as 800 men may have lived.

Now the remnants of that camp life are preserved at the C. E. Smith Museum at Cal State East Bay, although a few items found by the San Leandro boys were donated to the San Leandro History Museum (currently closed because of budget cuts, but occasionally open for special events funded by grants).

Ceramic soupspoons and wine cups with Chinese characters, blue-flowered rice bowls, black-brown temmoku soy pots, and ginger jars reveal the familiar eating materials that men an ocean away from home had brought with them.

The men wore loose pants and long tunics typical of the dress worn by farmers in China. They played traditional Chinese games such as mah-jongg and pai-gow.

Opium pipes and boxes reveal one means of escape from the reality of their hard life. Rusting pieces of metal tools, railroad tracks, metal linings from sluice boxes, a pickaxe, many shovels, numerous horseshoes, and pieces of a plow were among items discovered. There were no women at the camp, and the men did their own housekeeping.

Torrential Rains and a Breach of the Dam

In the fall of 1874, torrential rains started to wash away the sides of the first canal that was diverting the creek from the dam construction. Workers quickly built a wooden flume on piles to carry water over the washed-out rock channel where they were building the dam.  But the rain kept coming. Soon even the flume was overpowered.

Then, disaster.

The dam was breached. About 21,200 cubic yards of the compacted-clay dam debris was washed downstream. Arrowhead Marsh at the mouth of San Leandro Creek in San Leandro Bay may have been created when this massive amount of earth and clay washed downstream.  The distinctive arrowhead-shaped spit of land is not visible in an 1855 map, but shows up in an 1895 map of the area.

Work Continues

After the washout, weary workers, sloshing seven days a week through the mud and rain, lined the redesigned spillway with masonry and repaired the damage to the dam. They continued to heap and compact clay and earth to build it up even higher. Men continued to clear vegetation from the land in the valley where the lake would rise. When the dam core was high enough, Chabot supervised the construction of ditches and flumes from high up Grass Valley Creek, to use waterpower to sluice dirt and gravel down to the dam site. Hoses with nozzles at the dam site washed the dirt down the front and back of the puddle wall. This gigantic blanket of earth widened and strengthened the dam core.

Since the lower road through the valley would be covered by the water rising behind the dam, Chabot had the men construct a high road along the canyon rim.  This road is still the basis for the Lake Chabot road we use today. Finally, hundreds of trees were planted, especially eucalyptus, although many of those eucalyptus are now being replaced with native trees.


The project included the construction of three tunnels. The Chinese workers began construction of Tunnel No. 3, a secondary spillway, in 1888. This tunnel was blasted 1,438 feet through the rock hill and is ten feet wide by ten feet high, lined throughout with stone that the workers quarried from the banks of one of the creeks.

On September 16, 1889, four Chinese workmen were dynamiting outside the tunnel when an explosion killed all four. 

The four men who gave their lives in the construction of Lake Chabot dam were mentioned briefly and callously in the newspapers of the time. A century later, the Alameda County Historical Society dedicated a plaque to the four laborers, Ah Bing, Kim Yuen, Toy Sing, and Lock Sing, and it was placed near the outlet of Tunnel No. 3 in 1997. A new plaque replaced the old one in 2009.

By 1875, the dam was mostly completed.  The number of Chinese workers at the site began to diminish as various dam projects were completed over the next seven years.  By 1892, there were about 150 workers when the final hydraulic fill for the main body of the dam was recorded. That may have been the last year that workmen lived on the water company grounds.

What happened to those hundreds of men when the dam project ended? 

Again, history has been silent. But thanks to Jacqueline Beggs, George Miller, and four observant  San Leandro kids out for a hike, we know something about their lives at the dam site. Next time you take a walk at Lake Chabot Park, look for the plaque dedicated to the four men who died in its construction, and think of the lives of the hundreds of laborers who worked for years doing the hard and often miserable work of creating a reservoir for thirsty Oakland and San Leandro.

"The Chinese Laborers of Lake Chabot" by Jacqueline Beggs is available at the San Leandro Public Library.


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