Gold made Calaveras County, but it was water that made the mines. When gold seekers crowded into Murphys and the surrounding area in 1848 they soon discovered the importance of a reliable water supply. The Union Water Co. was formed in 1852 by the combination of companies already working to tap Angels Creek and the Mill Creek watershed. By 1854 the company had extended its reach to the North Fork of the Stanislaus River. Four years later it went into the high country to build Union Reservoir and improve its water supply through the long dry season. Also in 1858, the Union Water Co. acquired the Calaveras County Water Co., which had built a roughly parallel ditch from a North Fork diversion at McKays Point to Hunters Reservoir and then on to the mines. It was a better route and survived into the late twentieth century as the Upper Utica Canal.
In the late 1880s the Union Water Co. passed into the hands of the Utica Gold Mining Co. which already owned some of the richest mines in Calaveras County. The mining company expanded storage on the upper watershed by creating Lake Alpine in 1889-1892 and Utica Reservoir in 1903-1906. Its final reservoir was at Spicer Meadow, which was completed in 1929.
The Utica Company put its water to work running the heavy machinery of industrial mining. The first penstocks from what is now the Angels Forebay were run to the mines at Angels Camp in 1890 where the pressure of falling water was harnessed to operate air compressors, hoists and the stamp mills that processed the ore. It was also the dawn of the hydroelectric age. In 1895 the company set up a small power plant in Angels Camp and a thousand-foot transmission line to run electric lights in one of its mines. Other experimental plants followed, and in 1899 the Utica Powerhouse was built east of Murphys. When the Utica Mine closed in 1918, an air compressor assembly in Angels Camp was converted into a “temporary” electric generator. It served until a new Angels Powerhouse was constructed in 1940-1941.