Rainwater harvesting is very important in all aspects of water use including in the agriculture sector, domestic water use as well as commercial and industrial water use. There are various ways of harvesting rainwater with rooftop water harvesting being the most common way. Enhancement of self-sufficiency as well as provision for water in the future when the common source of water is unavailable is done by harvesting rainwater. Rainwater harvesting helps reduce the cost of purchasing water for various uses as well as promoting environmental conservation. Gutters are important in rainwater harvesting as they collect the rainwater and direct it to a collection point.
Collecting rainwater is mostly done into rainwater tanks which can be made of different materials. Plastic, concrete, fiberglass, aluminium metal, and stainless steel which should be resistant to rust and other chemical reaction are some of the main materials used in the making of rainwater tanks. Durability and affordability are some of the major factors that have an influence on the choice of a rainwater tank to be used. The most durable water tanks are usually the concrete tanks although they are less preferred to plastic tanks. Tanks used in rainwater harvesting are either placed on the ground surface or can be placed underground. Underground water tanks usually require that the water be pumped from the tanks since they cannot be fitted with a valve or a water tap.
Rainwater tanks should be covered at all times leaving just a small hole where the pipe discharging water can pass through so as to avoid unwanted materials from dropping into the water. Plastic rainwater tanks are used in many places since they come in different sizes, and volume and also one can find them almost everywhere. Plastic rainwater tanks should be placed on a concrete surface so as to avoid algae growth. The plastic rainwater tanks if possible should be placed in a place where they are not exposed to the solar since they a greatly affected by solar radiation which reduces their durability. Other rainwater tanks made of other materials used should be well fitted to avoid contaminants getting into the water more so if the rainwater collected is for human consumption.
Rainwater collected from rooftops for human consumption should always be sterilized through various means. This is because there are so many contaminants that settle on the rooftop and ones it rains they usually find themselves into the water. Chlorination and filtration are some of the ways of removing contaminants. Chlorination is usually preferred since it is not a costly method and it is also effective in sterilization. Loads of contaminants usually settle on the rooftop hence it is important to ensure that water is not harvested during the first rain so that the contaminants cannot find their way into the rainwater tank.