The biggest recorded flood to date in Gympie was in 1893 which peaked at 25.45 metres. In 1979, Bill Mulholland wrote about ‘the great flood’ of 1893 as “a legend that will persist into the future until, perchance, some day there occurs a still greater flood”. There hasn’t been (yet). In 1898, Gympie’s second biggest flood peaked at 22.00 metres and in 1999, Gympie and surrounds experienced it’s third biggest flood peaking at 21.95 metres which surpassed other great floods of 1955 and 1992 of 21.44 and 21.4 metres respectively.
Many of our greatest floods come from the drenching and torrential rains that travel south from the cyclones. The Mary River catchment covers an area of over 7000 square kilometres. The headwaters of the Mary are located in high rainfall areas around Maleny, Mapleton and down to Kenilworth. Heavy rainfall in these headwaters areas is likely to cause major flooding in the Mary River at Gympie. In Gympie, most floods, (nearly 80%), have occurred between December and April.
The Bureau of Meteorology operates a flood warning system for the Mary River based on a rainfall and river height observations. In consultation with the local council, the Bureau issues predictions of flood heights for the Mary River at Gympie whenever it is expected to exceed 12 metres on the gauge boards adjacent to Kidd Bridge. The objective is to provide between 21 to 27 hours warning for Gympie.
Minor, Moderate and Major Flooding
At each flood warning river height station, the severity of flooding is described as minor, moderate or major according to the effects caused in the local area.
In Gympie, moderate flood levels exceed 12 meters and major flood level exceeds 17metres. Today we look at some of the photos and stories from our major floods.
Read more about the Flood Warning System for the Mary River (Bureau of Meteorology) here – this link contains data on river height stations and the flood levels for first report height, minor, moderate and major flood levels as well as a summary of the flood gauge heights for the most significant floods in the region.