In earlier days, the infant settlement of
Cape Town had been supplied with water from
Table Mountain by way of canals or
"grachts" (such as Buitengracht, Kaizergracht and Heerengracht - now major streets). When these canals had to be covered due to public health concerns, the elders of the city agreed on the need to build a dam up on the Table Mountain slope above the growing city, to store water from the mountain's springs. This water would otherwise have flowed directly into the sea - a shameful waste in the eyes of the city's administrators. By the late 1860s, Cape Town was also facing severe water restrictions, partly due to its expanding population. The dam's actual construction was part of a huge expansion of infrastructure that was begun by the government of the country's first Prime Minister
John Molteno (after whom it was later named), who appointed the Cape's first water engineer Mr John Gamble, as well as the mayor
David Graaff. Soon after the dam was opened, the first power-plant in South Africa, the
Graaff Electric Lighting Works (named after the Mayor), was constructed next to the reservoir. The dam was intended to hold over 50,000,000 gallons of water, in sandy porous clay which presented an engineering challenge from the outset. The solution, only implemented years later, involved a mixture of excavation and masonry-supported embankments. ==History==