The prospect of installing rain water tanks or rain barrels for home rainwater harvesting is exciting but do not rush the process. There are professional installers but simple rainwater harvesting systems can be installed with a minimum of DIY skills.
Here are some tips:
Here is a simple online calculator that you can use to calculate your rainwater harvesting potential
Or use the method below:
Collection area (roof size):
To calculate your roof runoff, 1 millimetre of rain on 1m² will deliver 1 litre of water into your water tank. As a rough guide:
The size of your residence and your household needs should determine the size of the rainwater tank you choose. There are a range of products available in different shapes, sizes and materials. Generally, rain water tanks can be classed as:
In South Africa, water tanks can be found made from fibreglass, stainless steel, galvanised steel, concrete and polyethylene (‘plastic’ or ‘poly’ water tanks). We recommend polyethylene water tanks because of their ease of transport and installation, relatively low cost vs good longevity. Always choose a well-known brand such as JoJo Tanks – JoJo water tanks are guaranteed for 5 years, are rotational-moulded (no seams to split and crack), are available in an array of sizes and colours and are lined with an FDA-approved food-grade black inner lining to keep stored water safer and fresher for longer and inhibit algae growth.
Most simple rainwater harvesting systems require the rain barrel or rainwater tank to be placed at the lowest point, under the eaves to collect rainwater from the gutters and downspout using gravity. A simple leaf separator can be bought or made – this is attached to the top of the downspout to separate water from leaves and other debris that may be in the gutter. Another sieve or fine net may be place over the entrance of the hole that enters the rain tank to further remove finer debris. Some rainwater tanks, such as the JoJo 750 litre Slimline rainwater tank, are supplied with a stainless steel sieve as well as a tap/faucet at the bottom of the tank.
More sophisticated rainwater harvesting systems using small pumps allow the rain water tank to be situated away from the building, out of site or underground water tanks may be an option too (the JoJo 6000 litre underground tanks are popular in South Africa). Ensure that the water tanks are placed on a firm, level surface or water tank stand. The larger the water tank, the more critical the base strength. A concrete base is recommended or a certified water tank stand such as those supplied by JoJo Tanks is even better.
Most people start off installing a rain barrel or rainwater tank to supplement garden irrigation – very little filtering is needed for this purpose; a fine sieve will remove most debris. Rainwater is much better for plants than chemical-laden municipal water. If the rainwater from the rainwater tank is to be used for household use, the rainwater should be free of coarse particles and should be appropriately filtered to ensure it does not clog up washing machines, shower heads, etc. If the rainwater is to be used for drinking, ensure that you filter and/or purify the rainwater first (rain is pure before it reaches your roof but it may have collected contaminants from your gutters).
Rainwater harvesting is very rewarding – it not only decreases dependence on Mains water supplies but it saves money on water bills, ensures emergency water supplies during water supply outages and is good for the environment by reducing stormwater runoff in urban areas.
JoJo’s superior polyethylene plastic water tanks and steel water tank stands make JoJo Tanks the leaders in plastic water tank technology and the quality, affordability and 5-year guarantee on these water tanks make JoJo products one of the best choices in South Africa. JoJo’s water tanks and chemical tanks come standard with a number of features that are often lacking on cheaper/inferior plastic tanks made by other companies in South Africa.
We are authorised JoJo Tanks dealers in South Africa and dispatch orders directly from JoJo Tank depots to save on transport costs. Full range of JoJo Tanks products and JoJo water tanks for sale. CONTACT US for a quote on the right JoJo water tank or other JoJo product for you. Special discounts are available on multiple orders of chemical tanks and water tanks and to our commercial and government customers. We can usually delivery tanks and tank stands free of charge to business/commercial addresses in South Africa.
SPECIAL ON MULTIPLE ORDERS OF 10000 LITRE, 15000 LITRE & 20000 LITRE JOJO WATER TANKS AND CHEMICAL TANKS…CONTACT US FOR A FREE QUOTE!
(15000 litre and 20000 litre JoJo vertical water tanks & chemical tanks are available on order directly from JoJo Tanks’ main factory)