Rain water harvesting is the collection of water from structures such as roofs and storing it in storage vessels for domestic purposes. It can be purified to convert it into drinking water, used for daily applications and even utilized in large scale industries.

With increase in global temperature (which causes a fall on water tables), population growth and rapid climatic changes, the levels of potable water remain scarce in many parts of the world. Rainwater harvesting systems should be considered as an alternative for the continuous supply of water to households and even businesses. This method is economical, sustainable and safe if collected and stored in a proper manner.

Importance of Rainwater Harvesting Systems

There are many reasons as to why Rainwater harvesting is important. One of the main reasons is collected rain water will come in handy in times of water shortage and scarcity of rainfall.

A great number of people living in urban centers depend on bottled water which is neither cost effective nor dependable. This method can be a permanent solution to the problem of water crisis.

Rain water harvesting also provides us with a renewable natural source of water.

Benefits of Rainwater Harvesting Systems

  • It serves as an excellent back-up source of water in case of water shortage
  • Rain water is free and relatively clean
  • You will have control over your water supply
  • Water collected can be used for future purposes
  • It reduces water bills
  • Reduces demand for ground water
  • Reduces the chances of floods and soil erosion


Uses of Rainwater Harvesting Systems

  • Home consumption i.e. cooking, drinking, washing vegetables etc.
  • Domestic use i.e. agricultural purposes, washing vehicles, clothes, equipment, filling pools and many more
  • For industrial processing

Methods of Rainwater Harvesting Systems

  • Surface runoff method

Surface runoff method is used mainly in the urban areas where the rainwater flows away as the surface runoff.

This runoff is then collected and stored in ponds, tanks and reservoirs built specifically for this purpose.





  • Rooftop harvesting

Roof top harvesting can be executed in individual homes or in schools. To achieve this, gutters are installed on roofs (roofs will act as water catchment areas) so that the flow of rain water is directed in a particular direction for storage or for a defined purpose.

This method is effective and highly economic. However, roofs require high maintenance practices to control pathogens or bacteria that can accumulate in the gutters.






  • Dams

Dams are special barriers designed to trap water. When it rains, the water can accumulate directly in them or installing drainage systems that will ensure excess water will flow into them.






  • Underground tanks

Underground tanks are constructed by digging and creating space underground which is the cemented to reduce water leakages. Rain water is then directed into the tank using pipes after the top is sealed.









Disadvantages of Rainwater Harvesting Systems

  • Dependent on rainfall
  • The harvesting systems require regular maintenance
  • Amount of water collected depends on the water storage capacity