Rainwater Harvesting Using Rainwater to Meet Rising Demands
A specialty chemicals manufacturer uses a simple, yet effective rainwater harvesting system at its Mysore factory in India.
It needs no reiteration that with an increase in urbanisation and growth of population, there is an increased requirement of water. This makes wastewater management crucial for sustainability. In India, per capita water availability is on the decline, mainly due to an increasing demand for water from a rapidly-increasing population.
Moreover, with the rivers drying up, groundwater is depleting and canals are getting polluted. Other factors influencing/causing water shortage include massive industrialisation, increase in construction or infrastructure development and depletion of natural resources due to changing climate.
There is a dire need of reform in water management systems and for the revival of traditional systems. The ever-growing population and the water stress are calling for new approaches for water planning and management to avoid escalation of conflicts and to reverse environmental degradation.
The concept of water harvesting is not new for India. The system of collecting rainwater and conserving it for future needs has traditionally been practiced in the country. The traditional systems harnessed appropriate technology for rainwater harvesting and also for water management, where conservation of water was the prime concern. Traditional water harvesting systems were Bawaries, step wells, jhiries, lakes, tanks etc. These were the water storage bodies for domestic and irrigation purposes. People were themselves responsible for the maintenance of water sources and optimal use of water that could fulfil their needs. Broadly there are two ways of harvesting rainwater:
- Surface runoff harvesting: In urban areas, rainwater flows away as surface runoff. This runoff can be caught and used for recharging aquifers by adopting appropriate methods.
- Roof-top rainwater harvesting: It is a system of catching rainwater where it falls. In rooftop harvesting, the roof becomes the catchment, 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 augmenting the ground water level of the area.