CPW Hercules Department

California Powder Works was well capitalized and a strong competitor to Giant Powder. It continued research and development of new dynamite formulations, marketed under the Hercules trade name. Sales expanded under the direction of General Manager Joseph Powning. 

By 1879, however, explosions in the San Francisco factories made obvious the need to move production away from the expanding settlements. 

In 1878, the men of California Powder Works looked farther north and east in Contra Costa – the “opposite coast”, across the bay from San Francisco – for a new factory site. They found an ideal site just east of the town of Pinole, at the mouth of the valley of Refugio Creek. 

In 1878, not far from where the Ohlone had met the Spanards seeking their empire, the landowners of Pinole met the men of California Powder Works, seeking land for their dynamite factory. Just thirty years after Dr. Tennant had arrived in Pinole, new enterprises had been born in San Francisco to produce the new high explosives. Indeed, these men were inventing the very idea of an industrial organization based on scientific innovation, capital investment, and branded products. 

The California Powder Works purchased a 44.94-acre portion of Rancho El Pinole from the Martinez heirs in 1879. Subsequent purchases increased the site to about 3,000 acres, extending two miles up Refugio Valley.

Their new factory for Hercules dynamite would soon occupy the bayfront land in the Refugio Valley. The site was centered on a station of the Northern Railway, a line constructed in 1878 by two of the Central Pacific’s Big Four to connect Oakland with Martinez and beyond to Tracy. The railroad station was named Powning in honor of the general manager of California Powder Works. 

Upon Powning’s retirement in 1894, the station was renamed Hercules. The name of the product had become the name of the place.