With the main rainfall season over and at the beginning of our summer season, the Nelson Mandela Bay dam levels are critically low at just over 12%. Hopefully most households and businesses have already installed a water tank for backup supply and to collect rainwater.
With little rainfall expected over the next couple of months, we need to look at how we can save the water we currently have.
By re-using the water we already have, we lower the need for “new” water dramatically.
In my view, to flush toilets with clean potable water is the sin of the century. Why go through all the trouble and cost to clean the water from our dams, pump it to reservoirs, distribute it through kilometers of plumbing to businesses and houses, loosing loads of it along the way through leaks, just to get flushed away down the toilet.
Yes, it is hygienic and domesticated, but wasting 9-12l of clean drinkable water on every flush is a big waste of our scares water resource. What if we can re-use our shower, bath and laundry water to flush the toilets with?
We use the same water twice!
What if this can be a permanent solution and not only a temporary solution during droughts? You collect rainwater, shower with the rainwater, the greywater gets collected, and then used to flush the toilet. Same water used twice. If rainwater is used to do the laundry, this also can be collected, cleaned and re-used to do the laundry again.
Same water used over and over again.
If you have re-used greywater before, you will know that it is not so easy. Greywater can get foul and stinky very quickly and that is the main reason why people use it only on a temporary basis, or simply fall back on old habits by using clean water again.
Let’s have a quick technical look at greywater:
Definition of Grey Water
Grey water is defined as wastewater from:
- Baths
- Showers
- Hand basins
- Laundry machines
Under no circumstances may water be taken from toilets, bidets, or any dishwashing sources at all.
Properties of Greywater
Greywater has a remarkably high Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD) and therefore depletes the water of any oxygen in a very short time span. This creates ideal conditions for anaerobic bacteria to breed and produce methane and hydrogen sulphide as a by-product of their metabolism. This is the reason for the typical grey water smell that can occur as well as the production of sludge.
It is therefore advisable not to use raw/untreated greywater. It needs to undergo some cleaning before it can be used again.
A sustainable solution for recycling water
Green Overall has spent a lot of time in developing a greywater cleaning system that is both functional and cost effective. The aim is to develop and install a greywater system that is sustainable and not only a temporary solution.
We have two systems available:
1. Greywater for irrigation purposes:
This system collects greywater and spray it out on the garden. Some cleaning happens to prevent bad smells.
2. Greywater for re-use
With this system, greywater is cleaned to clear odourless water again. The cleaned greywater is non potable and can safely be re-used for toilet flushing, laundry, topping up the pool etc.
Cost of the system
Cost of the system will be determined by the difficulty of the installation. As most installations are retro fit, we need to do a site visit before quoting the customer.
Points we need to look at:
How accessible is the current greywater outlet points.
Sometimes the outlet points are underground or to low down to be able to collect greywater.
Space and position of the greywater system.
Depending on the type of greywater system, we require space for the tank/tanks and pump/pumps. Electrical supply and plumbing back into the house need to be considered.
Size of the greywater system
How much greywater is produced and needed to be cleaned. This will determine the tank sizes to be used.
Cost for an irrigation greywater system is around R8000 – R12,000.
Cost of the greywater re-used system is around R25,000 upwards.
Size of the system
The Green Overall greywater systems are scalable. From 260l/day to 20,000l/day system.
For more information of to request a booking for a quote, please use the below contact details.
admin@greenoverall.co.za
Frans@greenoverall.co.za
087 086 3020
