of Lake Parramatta Dam. In the latter capacity he may have modified the dam design and recommended the use of specific mortars in the joints between the stones. In October 1858 he was appointed Engineer-in-Chief for Harbours and River Navigation in the Public Works Department which he directed until he retired in December 1888. During that time he carried out many important harbour and hydraulic works including the initial development of the Port of Newcastle. Other works included construction and excavation of breakwaters, basins and docks at Wollongong and Kiama; improvements at the mouth of the Clarence and Richmond Rivers; a harbour of refuge at Trial Bay; extensive wharfage in Sydney harbour, and enlargement of the Sutherland Dock at Cockatoo Island Dockyard. Moriarty was also significantly involved in devising the Upper Nepean Scheme for Sydney. Cecil West Darley (1842-1928) Cecil Darley became Principal Assistant Engineer Harbours & Rivers of the Public Works Department in 1881, under Moriarty. Under him "many of the water supply works in the Colony were constructed". Darley succeeded Moriarty as Engineer-in-Chief Harbours & Rivers in 1889 and became Chief Engineer PWD in 1896. In 1898 Moriarty recommended a raising of Lake Parramatta Dam. He is renowned for the thirteen thin arch dams built to his direction around the beginning of the 20th century and described by Wade. William Randle (Randall) William Randle was responsible for construction of the first steam railway in Australia (in Melbourne) and for building Fort Denison (sandstone masonry) in Sydney Harbour. He built the first railway in NSW from Sydney to Parramatta where he achieved outstanding progress using "modern methods" of shifting spoil in wagons on rails. His superior and innovative construction skills were again demonstrated in constructing Lake Parramatta Dam. The place is important in demonstrating aesthetic characteristics and/or a high degree of creative or technical achievement in New South Wales. Lake Parramatta Dam has state significance for its technical innovation and achievement because: It was one of the first arch dams ever built (the first in Australia, the 11th in the world). It was a very economical dam, requiring the minimum quantities of material, all available locally except the cements. While there is no conclusive evidence that the design had a theoretical basis, the fact that Percy Simpson, the first known person involved in the dam's design was also involved in the construction of high masonry walls on the Great