31-03-2017, 12:24 PM
Rainwater harvesting is a technique for collecting and storing rainwater in reservoirs or natural tanks, or infiltration of surface water into subsurface aquifers (before it is lost as surface runoff). One method of collecting rainwater is harvesting on the roof. With the harvest on the roof, most surfaces - tiles, metal sheets, plastic, but not grass or palm leaf - can be used to intercept the flow of rainwater and provide a home with high quality drinking water And storage throughout the year. Other uses include water for gardens, livestock, and irrigation, etc.
Rainwater harvesting provides an independent water supply during regional water restrictions and in developed countries is often used to supplement the main supply. Provides water when there is a drought, can help mitigate low-lying flood and reduces demand in wells that can allow groundwater levels to be sustained. It also helps in the availability of potable water since rainwater is substantially free of salinity and other salts. The application of rainwater harvesting in the urban water system provides a substantial benefit to both water supply and wastewater subsystems by reducing the need for clean water in the water distribution system, less rainwater Generated in the sewage system.
There has been a large body of work focused on the development of Life Cycle Assessment and Life Cycle Assessment methodologies to assess the level of environmental impacts and the money that can be saved by implementing rainwater harvesting systems. More development and knowledge is required to understand the benefits that rainwater harvesting can provide to agriculture. Many countries, especially those with an arid environment, use rainwater harvesting as a cheap and reliable source of clean water. To improve irrigation in arid environments, soil ridges are built in order to trap and prevent rainwater from running down hills and slopes. Even in periods of low precipitation, enough water is collected to grow crops. Water can be collected from roofs, dams and ponds can be built to maintain large amounts of rainwater so that even on days where there is little or no rainfall, there is enough available to irrigate crops.
