report on rain water harvesting for 7th class
Answers
Rainwater harvesting is a viable option to supplement city water for non-potable human uses, such as irrigation. The overall efficiency of a rainwater harvesting system to supplement city water increases as area increases. The system would be highly effective in high commercial regions where there are warehouses and large buildings. These areas also contain less lawn area, so that the water can be used for uses beyond irrigation. In order to display the potential of the rainwater harvesting project for a heavy commercial area, Ontario, CA was chosen as a sample site. Ontario is an area with many commercial facilities, when all of the roof area is considered with the average annual rainfall at 16 inches, a total of 2,200 acre-feet per year of water can be collected, this can meet the demands of 10,000 people. In fact, the Toyota facility located in Ontario has a roof area of 380,000 square feet. When taking into consideration the average rainfall, this building has the ability to collect 3 million gallons of water. This single facility can not only meet the needs of the small patches of lawn surrounding the building, but can supply enough water for 41 people at 200 gpcpd or the water can be used to recharge groundwater levels.
The simplicity of the model and the low overall cost to install the system makes rainwater harvesting easily translatable for use in developing regions. The rainwater harvesting project was specifically chosen because of its potential to be used to help those in developing regions who do not have easy access to clean and local water sources. The water quality data shows that the water is clean for non-consumption purposes; although, a simple filtration system may have the ability to take the water into the potable range. The water collected from the harvesting system is actually cleaner than many water sources found in developing regions. In developing regions with a growing industry sector, water sources are often contaminated by outflow of waste from the facilities as many countries do not have stringent outflow laws. In areas with high populations, waterways used for drinking water are overdrawn and are used for purposes such as the cleaning of clothes and bathing. Rainwater harvesting can prevent the need to travel far distances to obtain water and can help the overall health and growth of communities.