High Quality Content by WIKIPEDIA articles! Yan Yean Reservoir is the oldest water supply for the city of Melbourne, Australia. It is built on the Plenty River a tributary of the Yarra River, 30 km north of the city. A 9.5 metre embankment holds back 30,000 megalitres (30 million cubic metres) of water. Work began in 1853 at the height of the gold rush, and it took four years to construct at a cost of Pds. 750,000. The reservoir is managed by Melbourne Water as part of the water supply system for Melbourne. At the time of its construction in 1857 it was the largest artificial reservoir in the world. It was designed by James Blackburn, an English and former London sanitary inspector who was transported to Tasmania as a convict following charges of embezzlement. After being pardoned he came to Melbourne in 1849.