The largest employer of its time in the Diablo Valley came to Concord three years after it incorporated, in 1905. The Cowell Lime and Cement Company built its town of Cowell that year and put men to work quarrying rock from the ridge on the east side of Ygnacio Valley. They carried the rock in the company’s narrow gauge railroad’s dump cars to the crusher from where it went into the roasting kiln and became cement.
Carloads of sacked cement left Cowell daily on the company’s standard gauge Bay Point and Clayton Railroad. At Bay Point, nine miles from the plant, the cars went on their way to customers over the Southern Pacific, Western Pacific, or Santa Fe railroads.
As early as 1910 farmers threatened to sue over the air pollution which coated their vines and orchards with a fine cement dust. The cement company built a 235 foot high smoke stack in 1934 in an effort to dissipate the dust into the atmosphere where it wouldn’t fall on a populated area.
Labor negotiations in 1947, in which the company was requested to pay five or six dollars a day, closed the plant.
Cowell Historical Society