The Folsom Powerhouse
Prepared by: Daniel A. Bell, Associate State Archaeologist

View of Old Entrance Road to the Powerhouse     View of the Powerhouse from top of forebay

Interior view of Powerhouse, looking north     View of the north face of the Powerhouse and blacksmith shop from the top of forebay     View of office, blacksmith shop, and garage


The Folsom Powerhouse is listed on the National Register of Historic Places (1981) as being significant in the areas of engineering and industry on the national level. It has been said that it represented a momentous advance in the science of generating and transmitting electricity. In 1895 the facility brought high-voltage alternating current over long distance transmission lines for the first time. It is also a National Historic Civil Engineering Landmark (1975), a National Historic Mechanical Engineering Landmark (1976) and is designated as California Registered Historical Landmark No. 633 (1958).

Historic Setting
The Folsom Powerhouse, located on the west bank of the American River, may have seen more than one American or Canadian fur trapper in the 1830s and 1840s. While habitat for fur-bearing animals best suited for the fur trade was farther up stream, the gently sloping, thinly wooded terrain for the Folsom Powerhouse environs made it preferable for transportation by foot traffic and pack animals. There is no evidence that this was an often- used campsite by trappers, but it is likely that many passed this way.

The Gold Rush, as it did in so many other places in California, changed this dramatically. There is no documentation found so far that verifies gold mining at this particular location as early as 1848. However, it has been established that miners were working all along the stretch of the American River by late summer of that year. In 1849, the mining camp of Negro Bar was formed on the river terrace, just downstream from where the powerhouse is today. A few of the town's buildings may have been located this far up-river, but no features or historical documentation clearly indicates their presence. There are placer mining features within the powerhouse project area that pre-date the hydroelectric plant's construction; but so far, no evidence has been found indicating whether they date as far back as the period when Negro Bar was in existence (1849-1854). Placer gold mining in this general area of the American River was a continuous activity for more than 50 years after James Marshall's discovery.

In 1856 the first railroad West of the Mississippi, was established between Sacramento and the new town of Folsom. The California Central Railroad's (CCRR) track skirted the site of the future powerhouse on the east, roughly following the route of present-day Riley Street and Leidesdorff Street. A substantial railroad trestle crossed the American River at about where the Rainbow Bridge is today. The Sacramento Valley Railroad (SVRR) endeavored to create a rail link between the rapidly growing river city and the gold mining towns of the central foothills. The SVRR built shops (substantial buildings made of brick) and a rail yard in Folsom, also near the present location of the powerhouse. Keeping up with the region's expanding economy and population, the CCRR constructed a rail line between Folsom and Lincoln, just west of Auburn, in 1861. The Central Pacific Railroad acquired the CCRR, and removed its tracks between Folsom and Roseville in 1868.

Powerhouse History
Gold mining had created the town of Folsom, and indirectly lead to the construction of the Folsom Powerhouse. The man who first sought to harness the American River for generating power for industrial purposes came to California in 1850 following the lure of gold. By the early 1860s, Horatio Gates Livermore had gained control of the Natoma Water and Mining Company, a firm that had built a network of dams, ditches, and reservoirs that supplied water to the numerous gold mines in the American River area. Looking beyond the immediate service to these mines, Livermore hoped to apply waterpower to operating a sawmill and other industries in and around Folsom. In the mid 1860s, he started construction on a dam to provide a holding pond for the logs cut in the higher foothills, and sent down the river. This task was more formidable than he had anticipated, since labor costs would be so expensive for quarrying the stone and building the dam and system of canals and ditches. The Natoma Company (Livermore) start built. By the late 1880s, a settlement was finally reached, and state officials agreed to provide prisoners for the dam construction.

Much had changed, however, while the delays held up the project. Livermore had died, and his vision of providing waterpower for infant industries in Folsom had to be revised. His two sons (Horatio P. and Charles E.) pressed ahead with the dam construction and the sawmill project. However, instead of building a system providing water for an industrial network driven by water wheels, the Livermores had embraced a new technology in their plans - hydroelectric power, that is, electrical generators powered by water turbines. Emerging from its experimental stages, the electrical power industry was trying to gain a foothold in manufacturing and transportation. A few electrical power plants had been successful on a limited basis in Germany and New York in the late 1880s and early 1890s; however, nothing had been attempted that was on the scale of the Livermore's endeavoring. They sought to construct a canal 9,500 feet long providing water power to four of the largest electrical generators that had been built up the stone dam across the American River, and the bulkhead and headgates for the canal, and the canal itself were finished in 1893. Folsom State Prison was the first to benefit from the dam when it put its own hydroelectric powerhouse into operation, also in 1893. Within two years, the Natoma Company's main powerhouse complex was completed, and was ready to transmit power to Sacramento. It consisted of four 750-kilowatt electrical generators (also called "dynamos"), each more than eight feet high, weighing more than 57,000 pounds. They were manufactured by the General Electric Company, and to quote a contemporary account: "these are without doubt the largest three-phase dynamos yet constructed..." (Journal of Electricity, vol. 1, No. 3, Sept. 1895). Driving these generators were four McCormick dual turbines with a capacity of 1260 horsepower for each pair, which in turn were driven by water surging through four eight-foot- diameter penstocks. The generators have been altered a little over the years, and the governors for the turbines were replaced early in this century. However, the basic equipment is still in place, and was in operation until the hydroelectric plant shut down in 1952.

The Livermore brothers, in partnership with Albert Gallatin (president of the Huntington, Hopkins Hardware Company) formed the Folsom Water Power Company, controlling the dam and the canal, which supplied water to the Sacramento Electric Power and Light Company, also owned by the Livermores and Gallatin. The latter firm operated the power plant at Folsom, the substation in Sacramento, and the streetcar lines in that city. On July 13, 1895, with only two generators in actual operation, electricity was successfully transmitted over uninsulated copper wires the full 22 miles to Sacramento. Newspapers in Sacramento and San Francisco covered this event in detail on their front pages the next day. Sacramento celebrated this technological breakthrough with a "Grand Electric Carnival" on September 9, 1895, stringing electric lights along its downtown streets, and decorating the State Capitol with thousands of bulbs. The whole affair caught the attention of the entire state, and even the nation.

While hopes were high for the future of electric power, the Sacramento Electric Power and Light Company had its problems with this new technology. One of the generators ran out of control in 1901, shattering the armature, and the sand, silt, and small gravel that washed into the penstocks from the forebay wore down and damaged the turbine blades on a regular basis.

Despite these setbacks, the Livermores and Gallatin remained confident that electrical power had a solid future. Demand for more electricity continued to grow in the Sacramento Area. Responding to this, they built another, smaller powerhouse in 1897, just below the main powerhouse at the mouth of the tailrace, to take advantage of the 25-foot difference in elevation. This power plant had only one 750-kilowatt generator, powered by a unique continuous rope drive from the turbine.

The success of hydroelectric power development and the expanding popularity of electricity for lighting and for industry and public transportation soon outstripped the capacity of the Folsom Plant. Within a few years after the second powerhouse was built at the Folsom complex, businessmen, investors, and engineers were constructing hydroelectric plants (with more powerful generators) that harnessed water from the Feather River down to the Tuolumne River for rapidly expanding distribution networks providing current to homes and factories in the San Francisco Bay Area.

By the early 1900s, the Folsom Powerhouse was on the brink of becoming an obsolete plant. The unpredictability of the American River water flows continued to plague the Folsom Powerhouse to the point that power transmission to Sacramento began to be interrupted on an intermittent basis. The Livermores were forced to buy electricity from the new Colgate hydroelectric plant on the Yuba River, which was owned by the San Francisco-based California Gas and Electric Company. By 1902-1903, that company had acquired the Folsom Powerhouse, along with several other power plants in the foothills. In 1906, this firm was reorganized to form the Pacific Gas and Electric Company, and from that time on, the Folsom Powerhouse remained in the control of P.G.&E.

Although surpassed in capacity and efficiency by newer, larger power plants in the P.G.&E. system, the Folsom Powerhouse still was capable of supplying electricity at a reasonable cost. The company continued to update its operation, and installed new governors in 1906, with new transformers on the second floor. In 1916, Sacramento County built a concrete bridge over the mouth of the forebay for the Leidsdorff Street connection to Greenback Lane, across the river to Orangevale. Construction of the bridge probably lead to installation of the iron pipe railings and electric lights around the forebay for public safety.

P.G.&E. drawings indicate that several substantial changes occurred at the Folsom Powerhouse in 1918, or just thereafter. Four large transformers and three large oil switches were installed just north of the main powerhouse. The one-story, long rectangular building up the hill to the west of the powerhouse was probably constructed not long after the transformers went in. It provided office space for the plant manager, a machine shop/blacksmith shop, and an automobile garage for the powerhouse. The lower powerhouse underwent substantial changes, too. Its original generator was removed and taken to another power plant in the P.G.&E. system. After considering abandoning this facility altogether, the company decided to install a new generator. A new storage building was also built at the south end of the main powerhouse. Finally, there was extensive landscaping put in around the office/shop building in an attempt to beautify the grounds at the powerhouse.

The improvements made to its facilities and the upgrading of its transformers expanded the capacity of the powerhouse sufficiently making it a productive operation for the needs of the twentieth century. While the continued growth in hydroelectric power up to World War II stimulated innovations and improvements in the technology of the electrical power industry, the operation at the Folsom plant continued through the late 1920s and the Great Depression of the 1930s using the same basic machinery of an earlier age. Why the Folsom Powerhouse was retained in the P.G.&E. system is a subject of speculation at this point. Wood bearings and other early technology made the facility increasingly outdated and difficult to operate. The fact that the four original generators and turbines were still running after forty years of operation was evidence of their quality engineering and design. Officials at P.G.&E. no doubt recognized this, and kept the plant running because it could produce needed power that could serve a local market, or be readily integrated into a larger power grid.

The lower powerhouse had problems from its beginnings, and even after a new generator was installed in 1923, replacing the 1897 dynamo, that facility only operated for a short time after being restarted. So despite the investment, this plant was finally shut down in 1924, and was never reactivated.

The historic importance of the main powerhouse, however, was recognized by P.G.&E.'s managers fairly early in this century. A promotional publication of 1911 referred to the power plant as the "Old powerhouse in Folsom," projecting the notion that the company had been a pioneer in the hydroelectric power industry with years of experience behind it. There was also an advantage to be gained from the impressive brick structure that housed the power plant. It presented an image of importance and stability that reflected well on this relatively new company that was expanding in a young industry. As the years passed, P.G.&E. developed the public relations theme of "progress," promoting its contribution to the expansion of electrical power in California at a lower cost to the consumer. Just before the Folsom Powerhouse ceased operation in 1952, the company produced a film recounting its own history and the history of electrical power development in California. The narrator of the film was an "old timer" who knew the industry.

The Department of Parks and Recreation acquired the Folsom Powerhouse project area, along with about half of a mile of the canal, as a donation from P.G.&E. in 1958. The property was in good condition when it was brought into the State Park System, and restoration projects for the buildings were not programmed. Minor site development was done to accommodate park visitors. In the late 1960s or early 1970s, interpretive panels and displays depicting the history of the Folsom Powerhouse were installed in the garage at the north end of the office/shop building. Not long after this, the wood-frame trash screen at the mouth of the forebay under the east side of the concrete bridge was reconstructed. Starting around 1980, district and unit staff undertook more vigorous maintenance and restoration activities, repairing facilities damaged by repeated acts of vandalism and years without proper maintenance. Between 1987 and 1990, three major preservation projects were completed on the lower powerhouse, the main powerhouse, and the office/shop building. The state park volunteers on the Board of the Friends of the Folsom Powerhouse Association were instrumental in acquiring funds for the office/shop project, and the Association funded and planned the rehabilitation of the small visitors' center in the garage.

Reference material prepared by:
Staff, Northern Service Center
Staff, American River District
Frank Lortie, former State Historian II, Inland Region Headquarters
Gary Reinoehl, former Associate Archaeologist, Inland Region Headquarters