Here is the rainfall within 128 Km of the Mount Stapylton radar near Brisbane. The first map is for the 24 hours up until 9:00 AM, Thursday the 30th of March, 2017. The second map is for the following 23.5 hours. Combined they give a good idea of where the rainfall from ex-tropical cyclone Bettie ended up as it passed over Brisbane.
Looking at the map, Brisbane proper got of lightly. Regions near the city center copped as much as 200 mm, but other regions only got about 100 mm (including where I live). In contrast, areas near Caboolture copped 300 to 400 mm, as did the head waters of the Logan River (the area in the triangle formed by Greenbanks, Beaudesert and Boonah). That is the likely cause of the Logan River setting a record flood. Worst was the Gold Coast, with the area centered on Murwillumbah, which has copped more than 400 mm of rain, with some receiving as much as 500 mm. Small bickies compared to Proserpines 1 meter of rainfall in 24 hours, but still a lot. Indeed, a very lot for rivers with short catchments to handle.
For more information, the ABC has a good round up.