Image Source: RNZ
The floods in Hawkes Bay and throughout the North Island took several lives and countless livelihoods. How can we rebuild in a way that protects us in the future?
After the floods an Esk Valley resident described a shocking scene to NewsHub illustrating the sheer force of the rushing flood waters. He witnessed a house with a rib-raft floor pop its foundations then go on to float 600 metres down the road like a barge.
This image made us think. When we rebuild in Hawkes Bay, Auckland, Coromandel and other areas hit by the floods – how can we change our homes to minimise the damage if this happens again?
Building for flood-prone areas
In Auckland alone there have been 36,000 insurance claims related to the floods, totaling well over $2.47 billion. This shows the scale of the rebuild and illustrates how important it is that we build and repair our homes thoughtfully.
There are several ways to protect new homes from flood waters when rebuilding (or when building a brand-new home). First it’s important to start with fully understand your home’s flood risk, then enlist the help of the right professionals (including architects and engineers) whose recommendations may include the following.
Elevate your home
Lifting your home off the ground may be the most effective option to protect it from floods. Alternatively, experts may also recommend building up the ground under your foundations by up to 1-2 metres to minimise floods risk.
Maximise run-off and drainage
When it comes to flooding it’s important that your home allows water to run around it, and does not force water up against any part of the structure. This will reduce water pressure against the building and may increase the likelihood that your home will stay in place.
Strip drains in front of exterior doors and garages may also help reduce floodwaters from entering your home.
Raise electricals
Floods often damage air conditioning units, switchboards, dryers, washing machines and other electrical units. Raising these off the ground as high as possible may help reduce damage.
Think about your building’s foundations
Talk to your engineer or architect about what type of foundation is best suited to flood-prone areas. They may recommend shifting the bearing of the foundation to deeper ground and will pay close attention to the type of ground you’re setting your foundation upon (i.e. liquefaction or expansive ground).
Installing a stronger foundation may also be a good idea. The QPOD flooring system, which uses eco-friendly 100% recycled plastic pods in a raft foundation or continuous foundation, is one example. The QPOD raft system provides a stiffer and stronger product than a conventional 100mm concrete slab on grade.
To help ensure your foundation is fit for purpose QPOD also offers engineering and foundation drafting services that are customised to your project.
Location
Considering the recent devastating flooding event in Hawke’s Bay, a contemplation arises: should we rebuild in the river valleys at all, given that these have historically served as the natural flow-paths of rivers? In our pursuit of progress, we must acknowledge the potential risks that come with inhabiting these areas, and consider the importance of adopting a more sustainable and resilient approach to construction.