Brisbane flood map, 1974

Brisbane flood map, 1974. Based on field inspection, aerial photographs as well as information made available from the Brisbane City Council, this map was prepared by the Survey Office and published in February 1974.  The extent of the Australia Day floods is shown as a red line, while according to various heights at the Port Office gauge, ‘areas of probable inundation’ were shaded blue, pink, yellow, green and plum. This information was obtained from an earlier flood map produced by the Bureau of Industry in 1933. The location of the massive tanker, the ‘Robert Miller’, is shown downstream of Kangaroo Point where it broke its moorings during the flood. According to the Survey Office, while the map was compiled from ‘the best information available’, it contained a clear warning for users: ‘no warranty is given to the correctness of the flood perimeter shown hereon.’ Lack of reliable contour information in 1933 as well as physical changes to the flood plain and channel since would all affect the possible extent of a flood. This was demonstrated in 1974 when Brisbane River invaded further than expected while other areas remained dry. A copy of this map could be purchased for $1. Collection of the Museum of Lands, Mapping and Surveying