Rainwater harvesting is the process of collecting rainwater and putting it to good use. There are different ways in which this task can be accomplished.

Rainwater harvesting refers to the trapping and storing of rainwater so that it can be used at a later stage as the need arises. As the rain falls, water is directed to a suitable collection point.

It can also mean collecting rainwater before it penetrates the ground and becomes underground water. Harvesting mainly entails gathering something from its natural source.

Rainwater harvesting, from the common definition of harvesting, is a process that involves collecting rainwater and increasing its value by eliminating impurities or directing it to places where its use is highly required.

It’s a practice that has been around for many a year. The only difference is that better methods have been developed to make the process successful. New technologies have come into play, making the process easier and more efficient.

There are many ways in which rainwater can be harvested. Some of these methods are very effective and can assist in the collection of a substantial amount of water even for commercial activities while others are only suitable for harvesting water meant for domestic use. Every system has its merits and demerits. These are the common methods of rainwater harvesting:

Surface Water Collection Systems: Surface water is simply water that accumulates on the ground’s surface. When rainwater falls on the surface of the earth, it usually flows down slopes as it moves towards a point of depression where the moving water can collect. Surface water collection systems enable the collection of ground surface rainwater before it flows to other locations. Examples of such systems include rivers, ponds, and wells. Drainage pipes can be used to direct water into these systems. Water can then be fetched from these sources and then used for other purposes.

Rooftop system: These can also be used to harvest rainwater. They can be used to direct rainwater that falls on the roof of a building into containers or tanks. These tanks are usually elevated so that when the tap is opened, water flows at a high pressure. This method of rainwater harvesting is good because the accumulated water is mostly clean and usually requires no further treatment to make it fit for human use.

Underground Tanks: These are also ideal for collecting rainwater. They are constructed by digging into the ground and creating a space which is then cemented to reduce water infiltration. The top is also sealed and water is obtained through pipes directed into the tank. To get water out, pumps are used. Underground tanks are wonderful for harvesting rainwater because the rate of evaporation is reduced since they are located underground where sunlight does not really penetrate.

Rainsaucer: Sometimes one can decide to collect rainwater directly as it falls from the sky by using a rain-saucer. These look like upside down umbrellas or big funnels. Some are usually attached to a pipe so that the collected water is directed elsewhere. Some people also do a little improvisation by placing the collecting container underground with only the rain-saucer above the ground. It is a simple method yet effective.

Trenches: This is another great way to harvest rainwater for irrigation. When it rains, the water is directed to the farm using trenches. It is one of the traditional methods of rainwater harvesting that is still very much in use today.

Rain Barrels: These are also used for rainwater harvesting. They are specifically designed for this purpose and can be purchased from JB Rock. Rain barrels are used for harvesting rainwater that falls on rooftops.

Domestic Use: Rainwater harvesting is beneficial because it provides a source of water for domestic use. The collected water can be used for house cleaning purposes, flushing toilets, washing laundry and for cooking. When treated, rainwater is good for drinking. It is an easy way of obtaining water for use in the home.

Industrial Use: Industries can also harvest rainwater for use in some of their processes. Rainwater meant for industrial use is normally harvested in large scale. Such companies can construct their own dams or have underground tanks to store rainwater.

Supplementary Water Source: Many areas experience water shortages during summer due to lack of rain and because of the high rate of evaporation. It can be difficult to get a reliable source of water during these periods. Those who sell water may also increase their prices because of the high demand and short supply. Harvesting rainwater is therefore seen as a way of preparing for the sunny days when water is scarce.

Cost Effective: We basically harvest rainwater for free because it is naturally occurring. If you store enough water during the rainy season, you may never have to pay for water services again because you’ll have enough supply to last you through the summer. This saves you money by cutting down your monthly expenditure on water bills.

Reliable Flow of Harvested Water: Even though harvesting of rainwater depends on rainfall, once stored, the supply of the available quantity is guaranteed. You could have an uninterrupted flow of water from the place of storage if the amount harvested has not been exhausted. The same cannot be said when you depend on an outside source to supply your water. There is also the benefit of locational suitability because the source of water is in your place of stay.

Mitigates/Reduces The Impacts of Floods: Harvesting rainwater plays a key role in mitigating or reducing the impacts of floods. When rainwater is directed to farms through trenches or collected in dams, its movement is controlled. This prevents the accumulation of water in one area, something that often causes flooding. Rivers can also overflow and cause flooding in the adjacent areas. The negative impacts of floods are too many and costly. Harvesting rainwater is, therefore, an effective way of reducing the impacts of this natural disaster.

Building and Construction: Collected rainwater can be used for building and construction. The process of building a house requires a lot of water. Harvesting rainwater would thus avail water for this activity.

Helps In Preventing Water Pollution: Rainwater flowing on the ground surface can carry with it a lot of impurities and toxic substances. When it drains into water bodies, it pollutes them because of these impurities. Harvesting rainwater, therefore, prevents pollution of water bodies.

Irrigation: Rainwater is good for farming because once harvested, it can be used for irrigation especially during the summer. One can, therefore, have a thriving farm and realize a bumper harvest.

Saves Potable Water: Instead of using clean and treated water for other purposes such as washing and in the toilet, rainwater can be used. This saves potable water which would then be used for drinking and cooking only.