Parramatta Dam - Engineering marvel of the world!

 

Lake Parramatta Dam was the first large dam built in Australia, only the 11th arch dam built in the world, and the only ashlar masonry arch dam built in Australia. ('Ashlar' means stones hewn to rectangular shapes). This engineering marvel is highly regarded by engineers around the world.  The Parramatta Dam is the second example in the history of the world of a dam built using mathematical calculations and a curving wall – the first dam built in this manner is only 1 year older than Parramatta Dam. Parramatta Dam is a masonry arch-walled dam across Hunts Creek. It was constructed of solid sandstone quarried from the creek. Each block was carefully dressed to accurate dimensions and laid in courses 0.6m high. The dam wall extended about 4m into the abutments on each bank. It was completed in 1856 to supply water for domestic purposes; and was operational until 1909. In 1920s and 1930s dam was a popular bathing and picnicking spot. Now the dam is used for Water storage.

The people of Parramatta had been asking for improved water supplies almost since the town was founded in 1788 – while the river originally was wonderfully clean, soon after settlement the surrounding trees were cleared and run-off and sewage pollution left the river dirty.  Wells provided some townspeople with water and a public well was built in June 1815, however most Parramatta residents relied on water carts for their water, which would deliver water from the Parramatta river to storage cisterns at the houses.  By the 1850’s the river was often polluted by sewage and the water was unpleasant, and a Committee of Water Commissioners was established to determine how to provide the town with good clean water.  Choosing Hunts Creek rather than Toongabbie Creek, in 1851 the Commissioners recommended constructing a dam and piping water to homes.  Percy Simpson’s design was chosen, builder of Oatlands House and the Great North Road, and now Parramatta is blessed with an engineering marvel, the arch wall dam on Hunts Creek, at beautiful Lake Parramatta.