A blue water background texture and splash with droplets forming a crown shape. Shallow depth of field.

Smarts ways to (re)use or treat grey water at home

The key thing to remember about grey water is not to reuse kitchen water as grey water, because it has biological contaminants in it that can be tricky to reuse – especially if you aren’t treating the kitchen water to any great degree. It should be noted that many of the products we use at home include additives and chemicals that aren’t natural and can potentially be harmful to the environment. But what you can very easily and cost effectively do at home is redirect your shower or bath water into a rudimentary sand filter – as one way of cutting out some waterborne contaminants – and this water can then be reused in your garden.

That said, if you are a keen gardener and have your own compost heap, you can pour dirty kitchen water onto the compost heap as it aids the decomposition and keeps the compost moist, and through the decomposition process this water won’t add any contaminants to vegetables, for example. Vegetables, like tomatoes for example, love the phosphate in dishwashing liquid and it acts like an added fertiliser which can actually aid growth in such vegetables. However, before doing this it is also important to understand how your vegetables will react to, or appreciate, certain products and what their makeup is.

Another very easy tip is to keep a bucket handy under your shower to capture the cold water those first few seconds while you wait for the water to run hot. This is clean water and can be used to water plants or vegetables, or even flush the toilet.

And if you are serious about reusing as much water as you can at home, look at switching to natural cleaning products – products that natural biodegrade – as this will ensure the water you’re reusing won’t leave chemical petrochemical compounds in the garden. You will therefore be making cleaning products in the grey water more biodegradable, and therefore less harmful to the environment and more reusable.

Being water conscious is not just a fad! The reality is that we live in a very water stressed country. As such, to ensure that whatever you do can be maintained, it’s best to start with the easy things and until such changes become a natural part of your home and lifestyle.

Flow control in water-efficient buildings

Generally, when we talk about flow control and water efficiency for the inside of buildings – be it homes or commercial – the focus falls on sanitary fittings and fixtures, where the objective is to reduce the water requirement, but still achieve the same aim and without diminishing the quality of the function (for instance, flushing toilets, running water for washing hands, washing up and/or drinkable water). Some options here may include:

Flow restrictor or low flow fittings for taps: can either be retrospectively screwed onto a tap spout, for example, or other fittings can be integrated into the tap line to restrict flow. The amount of water changes from 12 litres a minute to as low as 2 litres a minute. It’s important to note though that with better quality taps the function or experience will not be diminished, as they bubble the water out which creates the feeling of the same amount of pressure, but with less water flow – and less water wastage.

Similarly, water saving shower heads available in the market can change the water levels from 22 litres a minute to 6 litres a minute, whilst still ensuring the user does not have a diminished shower experience and can wash normally – just using water a lot more efficiently. Further to this, the right shower head can also reduce the amount of hot water needed – because you are using a lower volume of water – and therefore you’re also using less energy to reheat the replacement water, which is an added energy efficiency benefit as well.

Then, most commercial office spaces – and most spaces in fact – are starting to use dual flush toilets, though it’s important to educate occupants/users properly on how to use it. When using the dual flush option, it is also important to size the bowl of the toilet to flush and clear at the reduced rate for the system to be as effective as possible.

Finally, there’s the low flow or waterless urinal. These urinals only need about a litre of water to rinse them when they’re being cleaned. It’s important not to use any products or chemicals like bleach for cleaning, because the urinal works on the principal of enzyme cleaning. The enzymes consume the biological matter in the urine, and provided you don’t mix and match your cleaning products there is no smell – and it is a water efficient way of disposing of urine.

On the outside of the building, it’s important to consider irrigation – irrigation consumes vast amounts of water per annum. New irrigation controls include moisture control sensors, and/or rain sensors, which means the irrigation systems will only deliver water when needed. With this, water wise planting should also be taken into consideration. While many indigenous plants are water resilient, due to the extreme changes we have been experiencing in both weather and rainfall patterns, businesses and landscapers alike should be looking at xeriscaping gardens, where such plants don’t require irrigation and can survive on just natural rainfall – making them low maintenance.

Article courtesy of Alison Groves WSP Africa

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