In this article, we have published an article on Rainwater Harvesting methods, Its History, importance, Application, Current status in India and conclusion.
What is Rainwater harvesting?
The accumulation and storage of rainwater to reuse at the site and not allowing to runoff is known as rainwater harvesting. We can collect it in many places like a river, roof, etc. and redirected to well, borewell, shaft, a reservoir with percolation, aquifer, etc.
We use it for watering of gardens, drinking for livestock, irrigation, domestic use with proper treatment. It is one of the oldest and simplest methods of supply of self-supply of water for households.
History of Rainwater harvesting
Rainwater harvesting can be tracked to the Neolithic age, where the construction and use of waterproof receptacles to store rainwater were built on the floors of the houses and village location near the Mediterranean sea in the west, Arabian desert in the south and Mesopotamia in the east. By 4000 BC, cisterns were an essential part of managing the water requirement in the houses.
There are many examples like the Greek Island of Crete, which had such large cisterns for rainwater harvesting from 2600 BC to 1100 BC. Rainwater harvesting was frequent in the Roman Empire, and it expanded with the expansion of the empire. The Venice depended on rainwater harvesting.
Fresh approaches are being discovered for the rain harvesting like RainSaucer, which is like an upside-down umbrella. Here the rainwater is being collected straight from the sky. This reduces contamination and makes rain saucer potential applications for potable water in developing countries.
The GroasisWaterboxx, a Dutch Invention, is also useful for growing trees by using the harvested and stored rainwater and dew.
They build check Dams across the streams to enhance the percolation of surface water into the subsoil strata. The percolation of water within the water-impounded area of the check dams is often artificially enhanced much fold by loosening the subsoil strata and overburden using ANFO explosives as utilised in open-cast mining. Thus, local aquifers are often recharged quickly using the surface water fully to be used within the season.
One of the primary purposes of rainwater harvesting is to use locally available rainwater to meet the water requirements throughout the year without the massive need for capital expenditure.
Good quality water resource, closer to populated areas, is becoming scarce and dear for the consumers. To solar and wind energy, rainwater is a primary natural resource of any land. The vast area is being covered by solar PV panels per annum altogether parts of the planet.
Solar panels also can be used for harvesting most of the rainwater falling on them, and drinking quality water, free from bacteria and suspended matter, are often generated by simple filtration and disinfection processes as rainwater is low in salinity. Recently cost-effective Rainwater collection within the already dug wells found to be highly active within the bringing spring water level up in India.
Advantages of Rainwater Harvesting
Rainwater harvesting provides the independent water system during regional water restrictions, and in developed countries, it is usually won’t to supplement the most supply.
It includes water when a drought occurs, can help mitigate flooding of low-lying areas, and reduces demand on wells, which can enable groundwater levels to be sustained. It also helps within the availability of potable water, as rainwater is substantially freed from salinity and other salts.
An enormous body of work has focused on the development of life cycle assessment and its costing methodologies to assess the level of environmental impacts and money that can be saved by implementing rainwater harvesting systems
Rainwater harvesting provides an independent water system during water restrictions. In areas where clean water is expensive or difficult to return by, rainwater harvesting may be a critical source of unpolluted water.
In developed countries, rainwater is usually harvested to a supplemental source of water instead of the primary cause. Still, the harvesting of rainwater also can decrease a household’s water costs or overall usage levels. Rainwater is safe to drink.
When drought occurs, rainwater harvested in past months is often used. If rain is scarce but also unpredictable, the utilisation of a rainwater harvesting system is often critical to capturing the rain when it falls. Many countries, with arid environments, use rainwater harvesting as an inexpensive and reliable source of unpolluted water.
To reinforce irrigation in desert environments, ridges of soil are constructed to trap and stop rainwater from running downhills. Even during low rainfall, they collect enough water for crops to grow. Water is often collected from roofs and tanks are usually constructed to carry enormous quantities of rainwater.
Application or Use of Rain Water Harvesting
Regarding Urban agriculture, rainwater harvesting in urban areas reduces the impact of runoff and flooding. The mixture of urban ‘green’ rooftops with rainwater catchments is found to scale back building temperatures by quite 1.3 degrees Celsius.
Rainwater harvesting with urban agriculture would be a viable thanking to helping meet the United Nations Sustainable Development Goals for cleaner and sustainable cities, health and wellbeing, and food and water security.
The technology is out there; however, it must be remodelled to use water more efficiently, especially in an urban setting. Kenya has already been successfully harvesting rainwater for bogs, laundry, and irrigation, and areas in Australia used to harvest rainwater for cooking and drinking.
Studies by Stout et al. researching the feasibility in India found RWH was most beneficial used for little scale irrigation, which provides income with the sales of produce, and overflow used for groundwater recharge
2. Domestic Use
In China, Argentina, and Brazil, people use rooftop rainwater harvesting to supply beverage, domestic Water, Water for livestock, Water for little irrigation, and how to replenish groundwater levels.
Gansu in China and semiarid northeast Brazil have the most essential rooftop rainwater harvesting projects happening. The rural population of Thailand, about 40%, utilises rainwater harvesting.
The Govt. promoted heavy rainwater harvesting within the 1950s. Within the 1990s, after government funding for the gathering tanks ran out, the private sector stepped in and provided several million tanks to non-public households, many of which still be used today this is often one among the most critical samples of self-supply of water worldwide.
Rainwater harvesting is mandatory for brand spanking new homes inbuilt New Mexico state capital Santa Fe, New Mexico.
Texas offers a nuisance tax exemption for the acquisition of rainwater harvesting equipment. In the UK, we often find water butts in domestic gardens and on allotments to gather rainwater, which is then won’t to water the garden.
3. Industry Use
Frankfurt Airport has the most critical rainwater harvesting system in Germany. The system helps save approximately 1 million cubic meters of water per annum. The value of the system was 1.5 million dm in 1993.
This technique collects water from roofs of the new terminal which has a neighbourhood of 26,800 square meters. It receives the water within the basement of the airport in six tanks with a storage capacity of 100 cubic meters. We primarily use the water for bathroom flushing, watering plants, and cleaning the air con system.
Rainwater harvesting was adopted at The Velodrome – The London Olympic Park – to extend the sustainability of the power. Despite this, it had been deemed that rainwater harvesting was a less efficient use of monetary resources to reach sustainability than the park’s blackwater recycling program.
Quality of Water Harvesting
Rainwater may have to be analysed properly and utilised in how appropriate to its safety. Within the Gansu, for instance, solar water disinfection is employed by boiling harvested rainwater in parabolic solar cookers before getting used to drinking.
While rainwater itself may be a clean source of water, often better than groundwater or water from rivers or lakes, the method of collection and storage often leaves the water polluted and non-potable.
Pre-filtration may be a common practice utilised in the industry to stay the system healthy and make sure it frees the water entering the tank from large sediments. Conceptually, a water system should match the standard of water with the top use.
However, in most of the developed world, high-quality potable water is employed for all end uses. Supplying rainwater that has skilled preliminary filtration measures for nonportable Water uses, like a toilet flushing, irrigation, and laundry, could also be a big part of a sustainable water management strategy.
Rainwater harvesting in India
The scheme was launched in 2001 and has been implemented altogether in rural areas of Tamil Nadu. Posters everywhere Tamil Nadu, including rural areas, create awareness about harvesting rainwater. TN Govt site. It gave excellent results within five years, and slowly every state took it as a task model. Since its implementation, Chennai had a 50% rise in water level in five years, and therefore the water quality significantly improved.
Karnataka: In Bangalore, adoption of rainwater harvesting is mandatory for each owner or the occupier of a building having the location area measuring Bangalore water system and Sewerage Board has started and constructed. The people of the Thar Desert have traditionally practiced rainwater harvesting in Rajasthan.
Maharashtra: Rainwater harvesting in Pune, at present, is compulsory for any new housing society to be registered. In Mumbai, Maharashtra, rainwater harvesting isn’t mandatory. The Mumbai council is getting to make rainwater harvesting necessary for large organisations.
Rainwater harvesting is an eco-friendly technique to save water. It also increases level of ground water. Effective use of this method help us to Save our earth. I hope you liked this informative post on Rainwater harvesting.