A past client of our company recently contacted us to share some data with us. In 2011 the client started experimenting with rainwater harvesting, collecting rainwater of 150sqm of roof on the one side of his house. The client became convinced that it is a viable option and contacted our company to come and install one of our Deluxe rainwater harvesting systems. At that point in time the client had already procured some components and tanks.
They have also done a few upgrades. To extend the life of the cartridge filters they have installed a sand filter prior to the cartridge filters. They also installed pump cover after they replaced the pressure tank with a Global water solutions pressure tank and pressure controller. They have also installed a graywater system to flush all the toilets thus furthering reducing their consumption of the rainwater
Use Rainwater exhibited at the Lifestyle EXPO at Hutchinson Park in Amanzimtoti. For the exhibit they have built a small rainwater harvesting unit to explain to, and educate the public how small household rainwater systems work.
It was a great attraction for many visitors, many of them inquiring about installing their own rainwater harvesting systems.
Use-Rainwater designed and installed a potable rainwater harvesting system for a tennis academy in Durban. The design required a 40000l rainwater harvesting system instead of installing a 15000l soak pit as was required by the Durban Metro.Tennis Plus is the first Tennis academy in South Africa that has built a private indoor tennis court. The court is covered by approximately 660sqm of corrugated roof.
One of our domestic clients recently indicated to us that he had harvested 163 000 litres of water over a 12 month period. His house is situated in Durban and we installed a small deluxe system with two 5000l water tanks recovering water of a 150 square meter roof.
It was calculated that he had saved approximately R4500 in water and sewerage charges over this period. By utilising the rainwater he had reduced his monthly consumption and because the EThekwini Metro has a sliding tariff for water (rate per litre of water is higher if you use more), his net water cost reduced significantly.
During the past year there were 2 major water interruptions in his area and in both instances his household had water available in the tanks over those periods
System installation cost was R29000 – thus a straight-line payback of 6.4 years. If you have take into consideration that water price increase will be 3% higher than inflation in the next 10 years the system will pay it back over approximately 5.8 years.
This DELUXE system will harvest rainwater offf a 200sqm roof and recover 200000 liters of water per annum that can be converted into potable water, effectively substituting municipal water with urified rainwater.
The system can be installed for between R49 000 and R55000 and consist of the following:
1. 2 - 5000l vertical rainwater tanks installed. (Customer to supply solid base) These tanks will be interconnected
a. Tanks will have overflows installed and are insect and rodent proof.
b. Tank level meter so you can always see the water level in the tank.
c. Low disturbance inflow into the tank. The bio-layer that forms inside the tank should not be disturbed by incoming water and we have designed a system that will not disturb the bio-layer resulting in cleaner naturally purified water.
2. Modifications and changes to the gutters to accommodate filter collectors. We will connect your gutters with 80mm piping.
3. Two - WISY RS raincollectors connected to the gutter downpipes to screen out any debris that is on the roof thus preventing it from entering the tanks. The screen also act as insect proofing for the rainwater tanks.
See this video of how the raincollector works
4. 1 - Independent first flush systems for the roof sections that will divert the first amount of rainwater from the roof and prevent it from going into the tanks. This water contains dust, bird dropping etc. and you do not want it to flow into the tanks
5. 1 - 220V high pressure booster pump with a pressure cut off and float switches – all which will be correctly sized for your household requirements. The system will deliver an average water pressure of 3.5 bar to your houses' water supply.
a. Note - customer must supply 220V external plug connection at installation point.
6. 1 –frame mounted filtration system which will consist of
a. 1 - Stainelss steel frame 1.2 x 0,65 and 0.9m high
b. 2 – 20inch – pleated cartridge filters
c. 1 – 20 inch Activated carbon and KDF media filter
d. 1 correctly sized UV light sterilizer that will kill all bacteria in the water.
e. Gauges, valves and drain valves
f. Blue PVC pressure pipe
g. Water meter and accessories
i. Frame will be covered with clear polycarbonate sheeting to protect it from the elements.
7. 1- Backflow valve and connection to the municipal supply (Max 4m of piping)
a. This system is a legal requirement when a rainwater harvesting system is connected to the municipal supply
i. It prevents rainwater from flowing back into the municipal supply and at all times maintains a physical air gap between the two types of water.
8. The system will be connected and commissioned where after pressure and water quality will be checked. Included in the cost will be one detailed water sample analysis by an accredited laboratory in Cape Town. This will ensure that you have peace of mind that your system is working and the quality of water meets drinking water requirements.
9. We will inspect and monitor the performance of your system every six months in the first year of installation.