WhAt is water harvesting ? Any advantages associated with water harvesting at community level. Write 2causes for failure for sustained availability of ground water ,?

Dear Student, A) The process by which rain water is collected and stored either to recharge the ground water or for use in the future is known as rainwater harvesting. The rainwater on the roofs of the buildings is collected through canals that drain the water into ground reservoirs. This stored water is later utilized. B) Advantages of rainwater harvesting : 1) it can be undertaken in any type of climate. the construction required is quite simple. rainwater is usually the purest form of water, so it can be used easily for domestic services. 2) They recharge the ground water. 3)They can be used for drinking and other domestic purpose. 4)Water can be used throughout the year. Reduce storm water discharges, urban floods and overloading of sewage treatment plants 5)Reduce seawater ingress in coastal areas. 6)They act as water for irrigation. C)A failure in the sustained supply of groundwater is due to the following reasons: 1. Few bacteria from the use of fertilisers or other sources can invade the groundwater making it unsuitable for supply to humans. 2. The use of fertilisers blocks the entry rainwater into the ground which decreases its level. 3. Overuse of groundwater in rural areas through pumps can cause a cut-off in the supply of groundwater in the urban areas. 4. Occurrence of groundwater is different in different places. So, at some places it s supply is more sustained than the other. Regards