The flooding of rivers following heavy rainfall is the most common form of flooding in Australia.
Most rivers and creeks within Victoria have been allocated Flood Class Levels.
These flood class levels, that is:
are used by the Bureau of Meteorology to categorise flood events and to broadly describe the impact.
Properties located near rivers and creeks may experience flooding due to heavy rainfall. This rainfall may have occurred upstream, but eventually the runoff enters the river/creek and arrives downstream. The extent of damage depends upon the maximum height that the river/creek peaks at.
Minor flooding causes inconvenience. Low lying areas next to watercourses are inundated that may require the removal/relocation of stock and equipment.
Some roads may be closed and low level bridges submerged.
Moderate flooding, in addition to the above, may impact homes, industrial areas, but this depends upon the river/creek. Additional roads to those affected by a minor flood may be affected.
The area of inundation can be substantial in rural areas.
Major flooding causes inundation of extensive rural areas and appreciable urban areas.
Properties and towns are likely to be isolated and major traffic routes likely to be closed. Evacuations may be required.
Flood class levels
Barwon River (at Geelong):
- Minor Flood Level = 2.3 metres
- Moderate Flood Level = 3.1 metres
- Major Flood Level = 4.3 metres
Moorabool River (at Batesford Bridge):
- Minor Flood Level = 2.7 metres
- Moderate Flood Level = 4 metres
- Major Flood Level = 4.9 metres