What is Rain Water Harvesting & How it Works?
The industry is one of the biggest consumers of water in India. It is estimated that the Indian industry consumes around 500 million cubic meters of water annually. Estimates from the World Bank show that 13% of the total freshwater withdrawal in the country is by the industry. Further on, the demand for water has been growing steadily at a rate of 4.2% per annum. From 67 billion cubic metres in 1999, the industrial water demand is expected to rise up to 228 billion cubic metres by 2025.
This increase in demand also comes on a backdrop of growing water scarcity in India. Data suggests that in the near future cities such as Delhi will effectively run out of groundwater. By 2030, around 40% of India’s population could be deprived of access to water if the crisis is not prevented. The industry is generally located outside the city and is connected to the city’s piping network. In cities such as Banglore, the industry also pays one of the highest water tariffs, at close to Rs 72 a kilo-liter.
As an industrialist, you are fighting a battle for water on two fronts. The availability and the cost of procurement for water.
A rainwater harvesting system could help you win on both these fronts with a significant margin.
The rainwater harvesting system captures rainwater from large surfaces or catchment areas such as roofs and directs it to a holding tank. The harvested rainwater is then filtered and used for application.
Components of rainwater harvesting system
Catchment area
The catchment area of the rainwater harvesting system is the area where runoff of the rainwater is collected. It could be a rooftop, open ground, natural slope, or any other surface large enough to collect a considerable amount of rainwater. The catchment area could be as small as a few square meters or even as large as several square kilometres.
Inovar offers customized rainwater harvesting systems that function efficiently under the toughest space constraints to significantly improve the availability of water for your plant.
The catchment area should be cleaned regularly to improve water collection. If it is a rooftop, it should be cleaned of dirt and bird dropping or other material that could impact the quality or flow of water. If the catchment area is open ground, it should be regularly cleaned of foliage.
Filtration and flush
Filtration and flush devices remove common contaminants such as grit, dirt and foilage that is carried by the rainwater from the catchment area. The Filtration of these elements is important as they could contaminate the entire water in the storage tank if not filtered. Natural materials such as gravel, sand, as well as various fibers are widely used as filter media in the rainwater harvesting system. The filtration system is also useful when rainfall occurs after a long time because the first flow of rainwater often carries a lot of dirt within its flow.
Conveyance component
The conveyance component of the rainwater harvesting system works to convey the runoff through pipes gully, or channel flow to a specified storage facility.
Storage component
The rainwater runoff from the catchment area is stored in a facility designed as per the requirements and space constraints of your particular facility. Storage components could be as diverse storage tanks or reservoirs, underground cisterns, or near-surface aquifers. The storage tanks must be fitted with tight covers to prevent mosquito breeding and agal growth. Measures must also be taken to prevent contamination of the stored water.
Factors that impact rainwater harvesting system cost and design
Quantity and quality of rainfall
Indian monsoon has a very unpredictable pattern. When designing a rainwater harvesting system, studying the rainfall data of a particular place is required. 10 years of rainfall data is generally considered for the study. Additionally, the rainfall pattern of an area is also important. If the area has a short spell of rainfall and long dryer seasons, rainwater harvesting is an urgent necessity. However, this also means that the rainwater harvesting system must be robust and highly efficient. Such regions call for bigger storage tanks and larger pipes to effectively convey and store water.
Characteristics of the catchment area
The quantity and quality of the water collected by the rainwater harvesting system is determined to a large extent by the nature of the catchment area. Catchment areas with a smoother surface will enable a larger amount of water to be collected within a short time. Similarly, bamboo rooftops yield poor quality water as compared to other materials such as galvanized corrugated iron, aluminium, or cement.
The expert team at Inovar works closely with clients to understand their constraints. We know requirements to design a customized and cost-effective rainwater harvesting system.
Inovar is a technology-focused company that offers end-to-end water treatment solutions for facilities of any size. Our services include feasibility studies, engineering design, manufacturing, and installation. Additionally, all of our products are supported by Annual Maintenance Contracts to further reduce the maintenance costs of your rainwater harvesting system.
To explore our rainwater harvesting solution in detail, download the brochure