Following the Yan Yean and Toorourrong schemes, the Maroondah Dam scheme was the third water supply source for Melbourne. The Maroondah Aqueduct was built in 1886–1881 to supply water to the Preston Reservoir from a diversion weir on the Watts River. The level of the aqueduct was determined by the site of the proposed Maroondah Reservoir, preparatory work for which was undertaken in 1915–1919. Construction commenced in October 1920 and was completed in 1927. During that period, the capacity of the Maroondah Aqueduct was increased.
