Flooding effects around Brisbane and what it does to buildings

Flooding effects around Brisbane

Learn about flooding around Brisbane and how it may affect buildings.

Flooding effects around Brisbane. QBIS.

Some periods of flooding around Brisbane.

Predominantly, severe flooding has occurred in 1887-1893, 1908, 1931, 1974 and more recently in 2011 & 2013.
Another type is localized flooding that occurs much more often and possibly on a number of occasions, within any time frame.

Localised flooding.

Photo below is an example of flooding in the latter category as indicated by different water shadow lines on the concrete stumps. The property is in the Nundah area, a low lying north east suburb of Brisbane and as you can see by the photo, it floods often from a nearby creek.

Potential causes of local flooding:

Inadequate street drainage (or blocking of drains).
Nearby creek.
Overland water runoff from neighbouring properties.
Surface water not being able to exit from the property quickly enough.
Trapping of water on a property due to fencing and/or other obstacles.
Fall of the land causing water to accumulate.
Low lying areas and/or gully.

Effects flooding has on properties, buildings and owners

Building movement.
Damage to furniture and stored items.
Limit or stop access to property.
Other damage to buildings.
Having to relocate until flooding recedes.

Flooding of any sort, can cause movement of buildings to varying degrees. This is often dependant upon period of time flooding has occurred also possibly type of soil.

Good example of localised flooding.

Multiple water marks on a concrete stump indicating frequent flooding.

It doesn’t matter too much what the cause may be, the main concern is that it may happen way too often and when least expected, so be aware and prepared!

How does flooding cause building movement?

Other than forces of water against buildings, the following may also cause movement.

Sometimes indirectly from saturation of land sub-soil even if the property has not been flooded directly.
Soil type.
Footing construction and depth.
Saturation of timber structure. Wetting allows timber to be more easily bent, especially when it has forces upon it.

Worth knowing about flooding effects around Brisbane.

Make sure your property has sufficient drainage
Keep your property clear of obtacles that may restrict water flow.
If at all possible, do not construct buildings in the pathway of natural overland water flow.
Inform local Council if their drains become blocked.
Notify local Council if a nearby creek flow is restricted.