The December 1934 floods in Melbourne

In Victoria, many of the heaviest rainfall events occur when a depression develops over the State within an existing moist airmass. The area around Melbourne experiences its heaviest falls when such an event occurs just to the east or southeast of Melbourne, producing strong south to southwesterly winds. Just such an event took place at the end of November 1934.

The spring of 1934 had been very wet, with frequent heavy rain and storms, when on 29 November an active cold front crossed Victoria, relieving sultry conditions. Quoting the 1974 Victorian Yearbook: “Some hours after the front, barometers fell rapidly as a depression developed in Bass Strait. The south-west wind strengthened overnight and in Melbourne blew with gale force for most of Friday 30 November.” Torrential rain began falling in central Victoria and Gippsland on Thursday night, and continued throughout Friday. In Melbourne, 140mm fell in the 48 hours ended 1 December, but rainfall was much heavier in the hills east of Melbourne - which comprises the catchment area for the Yarra River - and over South Gippsland. In these areas totals exceeded 350mm within 48 hours, isolating towns through numerous landslides, submerged roads, and washed-out bridges. Heavy rain also fell in northeastern Victoria, and cold air accompanying the storm resulted in heavy - and quite unseasonable - snowfalls on the higher mountains.

The Yarra River, swollen by the torrents of water falling over its catchment, broke its banks, as did other metropolitan creeks and rivers. Many suburban areas were inundated, forcing residents to evacuate. In areas such as Moonee Ponds, in Melbourne’s west, such evacuations were not uncommon at that time; but in the eastern suburbs the flooding was easily the worst in the 20th century, and evacuations were necessary from some areas previously regarded as flood-free. Disastrous flooding was widespread over the Yarra Valley, South Gippsland, and the Latrobe River District, with major stock, crops and property losses. The damage was exacerbated by the gale force winds that accompanied the rain, causing heavy livestock losses through exposure, as well as much property damage. Very many trees were uprooted by the combination of high winds and sodden ground. In all, at least 36 deaths were attributed to the flood, and in Melbourne some 400 houses and factories were flooded.

The remainder of that summer, and also autumn 1935, was noteworthy for several other unusually heavy rain events in Victoria, a departure from the otherwise generally dry decade of the 1930s.