Founded in 1872 by an act of Massachusetts General Court, the system was developed as a series of reservoirs to serve the growing city's residents and industry at the end of the 19th century.

While it maintains reserve drinking water supplies at the Ashley and the Whiting Street Reservoirs.

[3] The Water Works is entirely responsible for drinking water supplies, infrastructure, and watershed land conservancy, however it does not maintain sewage or stormwater treatment infrastructure or services, which fall under the responsibilities Department of Public Works.

[8] More than 99% of Holyoke's households are provided water by the Reservoir System, however some homes in the Smith's Ferry and Rock Valley areas remain supplied by private wells.

[9] Those in Rock Valley draw from the Barnes Aquifer and may however require additional home filtration due to trichloroethylene (TCE) contamination from industrial degreasers dumped in the area by General Electric during the 1950s; for this reason the City no longer maintains public wells there following the closure of the Pequot and Coronet Hills wells in 1988.