The building of the Charlestown Navy Yard dry dock between 1827 and 1834 included the construction of the Engine House, also known as Building 22. Completed in 1833, the Engine House was the first major Charlestown Navy Yard building designed by Boston architect Alexander Parris. He also designed Quincy Market in downtown Boston and the Charlestown Navy Yard’s ropewalk and Building 24, the location of current restoration staff for USS Constitution.The Engine House, constructed with granite from Quincy, MA, contained the wells, the pendulum steam engine that powered the pumps, and the boiler room. These mechanisms, along with a large, brick-lined reservoir, were integral in discharging the water from the dock (depicted below). During a pump test recorded in September 1832, the pumps removed 637,500 gallons of water from the dock in one hour. At the time, the whole dock could be pumped out in 6 hours. The culvert connecting from the head of the dry dock to the Engine House (the red lines running from the dock to the building in the above image) was sealed in 1976. The USS Constitution Museum, which currently occupies the building, opened to the public that same year. The pendulum steam engine (shown above) and pumps were used until 1905, when the system was replaced with electric-powered pumps in nearby Building 123 on Pier 4. Today, modern diesel-powered pumps located at the foot of the dry dock can drain approximately 4.8 million gallons of water to empty the dock. After Constitution entered dry dock on May 18-19, 2015, it took about 9 hours to drain the dock completely.
– M. M. Desy & K. Monea