Conservation of water that we get from rain has become a necessity both in village and town. The process of collection of water from the rain is called rainwater harvesting. We carry out rainwater harvesting in the following ways:-
1)Rooftop rainwater harvesting for consumption as well as for recharging of groundwater.
2)Rainwater harvesting of water collected on the ground around the building for recharge of groundwater table.
3)Collection of surface water that may run off by check dam and other devices for storage in surface ponds, dams etc.
Rooftop harvesting for reuse and groundwater improvement
1. Harvesting roof water for reuse
The rooftop water is collected on the roof which directly leads into the storage tank through pipes. A bypass system may also be provided so that the water from the initial rain during the rainy season can be used for groundwater improvement and only clean water is led into the storage tank for domestic use. We should also introduce a filter media before the storage to collect all the Debris that will otherwise fall into the storage tank.
2. Harvesting for groundwater improvement
For this purpose, the rainwater can be recharged through an old well or an existing hole so that it will recharge the groundwater. We should remember that any seepage deep into the ground will take time and hence water should be stored at least for a few hours in the well or tube well before it slowly percolates into the ground.
The rate of percolation depends on the bottom strata in the storage well. Hence, the good pit or bore should end in permeable strata for the purpose to be fulfilled for proper recharge of the groundwater.
If the rainwater is led into a well fitted with sand, it is very important that a filter made up of synthetic fibre should be placed above the soil in the well so that it does not clog with time by particles and debris. This filter should be taken out and cleaned before the start of every rainy season.
Benefits of the rainwater harvesting system
Rainwater harvesting has many different benefits but the main is that it is a sustainable water management practice that can be implemented by anyone on many different levels from a simple rain barrel to a comprehensive rainwater harvesting system that integrates with an irrigation system or with household plumbing.