By Kritika Wadhwa,
There is nothing more essential than clean drinking water, yet a global water crisis means people are struggling to access the quantity and quality of water even for their basic needs.
Water scarcity already affects every continent. Water usage grew globally at more than twice the rate of population increase in the last century, and an increasing number of regions are reaching the limit at which water services can be sustain-ably delivered.
Rapid industrialization and disposing chemical waste into water bodies leads to pollution of rivers, lake and water-bodies. This is a global problem and needs a speedy solution. The supply of fresh water on this planet cannot be increased. So an alternative method must be sought for. One such method is harvesting rainwater.
What is Rainwater Harvesting?
Rainwater harvesting is the technique of storing rainwater during the monsoon/ rainy season for the purpose of using it during periods of water scarcity. Rainwater harvesting is best described as the method by which rain water is accumulated and stored with the intention of reusing it during the dry season or when there is a drought for basic household requirements.
‘Rainwater Harvesting’ is an easy and economical way to deal with this crisis. As people are becoming more and more environment responsible , rain water harvesting is gaining popularity leading to Eco – conservation and constructive use of natural resources.
The question of water security is at present a major issue in many parts of the world. One way to deal with this crisis is to adopt rainwater harvesting.
How rainwater harvesting solves water shortage problems?
Harvesting and collection of rainwater is a proper way that can be used to address the problem of the water crisis in various parts of the world. This simple water conservation method can be used to put forward a remarkable solution in areas where there is enough rainfall but not enough supply of groundwater.
When architects are designing a new home or a building structure, it is important that they think of implementing rainwater harvesting methods. It will enable the building to reduce reliability on other natural resources for water and in the long run, there will be energy savings, water savings, and resource savings.
Advantages of Rainwater Harvesting
In most plans, the harvested water is redirected to storage tanks, cisterns or reservoirs. The water is usually stored for later use. The roof of buildings is the best way to harvest rainwater. There are numerous advantages in doing so.
- EASY TO RUN AND MAINTAIN
The systems used for water collection is based on simple techniques that are very easy to maintain. The overall expenses used in setting up harvesting methods are much cheaper compared to other purifying or pumping means.
- DECREASES LOAD ON GROUNDWATER
Another important advantage is that it reduces demand for potable ground water. It is important especially in areas with low water levels or arid regions.
- REDUCES EXPENSES
Water that has been stored from harvesting can be used for several non-drinking purposes as well. It will immediately reduce oneʼs utility bills. It is ideal for both residential and commercial properties.
- SERVES MANY PURPOSES
Harvesting leads to collection of large amounts of water. Most rooftops provide the necessary platform for collecting water. Rainwater is usually free from harmful chemicals, which makes it ideal for irrigation purposes, car washing, gardening, etc.
Techniques of Rainwater Harvesting
The two main techniques of rainwater harvesting are:
Surface Runoff Harvesting : In urban area rainwater flows away as surface runoff. This runoff could be caught and used for recharging aquifers by adopting appropriate methods.
Roof Top Rrainwater Harvesting : It is a system of catching rainwater where it falls. In rooftop harvesting, the roof becomes the catchments, and the rainwater is collected from the roof of the house/building. It can either be stored in a tank or diverted to artificial recharge system. This method is less expensive and very effective and if implemented properly helps in enhancing the ground water level of the area.
There could be different methods besides the above two but these are most commonly employed.
Success of rainwater harvesting in India
- Ralegaon Siddhi, Maharashtra (Less than 300 mm) : Irrigation has increased from 80 – 1,200 acres, producing three crops a year worth Rs. 60 lakhs. The girls and boys of the village have won state-level competitions by learning swimming in this village pond. Hundreds of people visit everyday to see the miracle.
- Gandhigram, Kachchh, Gujarat (340 mm) : During 2001, although the village received only 165 mm rainfall, the reservoirs were brimming with water. Gandhigram topped in groundnut production in Mandvi district in 2002. The village is now planning a cooperative for processing and marketing agricultural products.
- Alwar, Rajasthan (Average Annual Rainfall – Less than 450 mm) : Arvari, a stream has been made a river. A forest has been created. 1058 villages have been made drought and flood free. Government has changed records of Alwar as a “Dark Zone” (water-deficit zone) to a “White Zone”. Water is available for drinking and irrigation after three years of no rains.
Future of Rainwater Harvesting
Global warming is taking its toll on the climate pattern across the world. Rains have become unpredictable in nature with some regions suffering with usual than longer dry spells, while some region are hit by incessant rain. Rain hit regions are unable to utilize or control the excess water, that leads to flood-like situation. Rainwater harvesting can help overcome the problem of flood, while also helping in storing excess water that can help in providing water to the water scarce region.
This technique of water management can help in overcoming major water-related problems, that are not only plaguing the world right now but can have a severe impact on the global population and environment in the future.