Did you know there was once a massive granite reservoir in Beacon Hill?
Long before the Wachusett and Quabbin Reservoirs that now supply water to Boston, the city’s original municipal water supply was Lake Cochituate, a reservoir in Metro-west. Due to Beacon Hill’s high elevation, the city selected the site behind the recently completed Massachusetts State House, to store and distribute water to the city. The site was too steep, so it had to be graded. Therefore, the top of Beacon Hill, where the beacon had long been standing, needed to be lowered to accommodate the reservoir. The soil was dug by hand and hauled by cart down to fill the old Mill Dam in the Bulfinch Triangle area. The reservoir, which opened in 1849, was unique in its approach. The design of the structure needed to minimize its footprint and reflect well on its surroundings in the prestigious location. In lieu of earthen bermed walls, as was the convention in most period distribution reservoirs, the design chose to create a watertight tank within a masonry structure. This made the structure the first elevated storage tank constructed in New England. Sheet lead was used to make the reservoir watertight (which likely led to a lot of health issues (hindsight is 20/20). By 1870, the poor water pressure made the Boston Waterworks build the Roxbury Standpipe, which relegated the Beacon Hill Reservoir to being an emergency water source for use only in case of fire or accident to the pumping-mains. In 1883, Boston Water Works sold the structure to the Commonwealth, who demolished it for the addition to the State House.