 The dam was completed in September 1940 . When built it was the longest concrete gravity dam in Australia , and also the second highest after the Burrinjuck Dam in New South Wales . As of 1997 of the 90 large concrete and masonry gravity dams in Australia the Canning Dam is still the fifth highest and the sixth longest . It is the largest concrete dam in Western Australia in terms of length of crest and volume of concrete . 
 The dam was completed in September 1940 . When built it was the longest concrete gravity dam in Australia , and also the second highest after the Burrinjuck Dam in New South Wales . As of 1997 of the 90 large concrete and masonry gravity dams in Australia the Canning Dam <a href='drop_aux' title='1'><mark>is</mark></a>still the fifth highest and the sixth longest . It <a href='drop_aux' title='2'><mark>is</mark></a>the largest concrete dam in Western Australia in terms of length of crest and volume of concrete . 
Da dam was completed in September 1940 . When built it was the longest concrete gravity dam in Australia , and also the second highest after the Burrinjuck Dam in New South Wales . As of 1997 of the 90 bigass concrete and masonry gravity dams in Australia the Canning Dam still the fifth highest and the sixth longest . It tdalargest concrete dam in Western Australia in terms of length of crest and volume of concrete .