Title: G6: Tropical Island Clean Water (D) AssessmentIntroductionI am investigating 2 methods Harvesting rain (method 1)and seawater distillation(method 2) of providing fresh water to a community of 100 people.Main:The research -Method 1 works by collecting all rain water from the roof of your house and leading it through a series of pipes and filters and into clean water reserves and not clean reserves for laundry, gardening and cleaning, which are connected to the houses with pumps. This costs about 2,000£ to 3,000£ excluding installation. Method 2 (reverse osmosis) works by extracting sea water from the ocean into wells on the shoreline. It then gets filtered through a multi media filter which consists of anthracite, sand, garnet, sand and/or pebbles. These filters remove large particles such as twigs and seaweed. In some cases a micro filters are used instead of multi media filters to pre treat the water. Later they are filtered through a cartridge filter which acts as a second stage of filtration. Cartridge filters for reverse osmosis are typically made of synthetic yarn type material compactly wound into cartridges. These remove even smaller particles such as sand and clay before the water is moved to the reverse osmosis membrane. Pressure pumps increase the pressure up to 1,000 psi. High pressure is needed to stop the naturally occurring osmotic pressure. The salt particles in the se water are rejected from passing through the membrane to the fresh water side. These are closed in a fiberglass shell. As the pressurized seawater passes through these membranes the water particles are forced through membrane leaving the salt molecules behind. The desalted water passes through the membrane at low pressure where it is collected in a tube and directed to one end of the pressure vessel. The concentrated salt stream passes to the other end of the membrane and into a tube that is directed to the ocean. The clean water is connected to houses and is now potable. Pros and Cons of method 1:Method 1 is not very expensive so it is economically friendly. It also does not use a lot of power, it is very eco friendly. Though it is quite eco friendly method 1 is not very ethical because a big pit must be dug up to place the water tanks and it could displace some wildlife such as groundhogs and rabbits as they are housed in the ground. It is socially positive because it means that people are less likely to die of thirst. Although it is positive in many ways, there is not a lot of accessible rain water and every home would have to be equipped with one to be able to have enough. There would have to be many reserves so that not a drop of water is wasted. Pros and cons of method 2:Method 2 is costs around 30 million to be made so it is not very economically friendly. It is also not very eco-friendly and ethical because it will displace a lot of wildlife out of their natural habitat which could lead to having to import more food and that will also cost a lot and will not be eco friendly. Though it is not eco friendly noare ethical there is more access to seawater than rain water. It is very effective. Only one of distillation plant would be sufficient – unlike the rain water harvesting method – for the whole culture and everybody would have access to clean water. With all this Data the sea water distillation is the best and more worth it because you have access to sea water all year around and you wouldn’t have to worry about not always getting water when you turn on the tap. ConclusionIn conclusion I think that method 2 is the best because there is more access to seawater than rainwater.https://www.youtube.com/watch?v=pNXooT2FVXMHomesteadonomics. “Rainwater Harvesting – Home System Tour.” YouTube. YouTube, 01 Oct. 2015. Web. 22 Jan. 2018https://www.renewableenergyhub.co.uk/rainwater-harvesting-information/rainwater-collection-cost.htmlUnknown. “Cost of Installing Rainwater Harvesting System.” Cost of Installing Rainwater Harvesting System : Rainwater Harvesting Information. N.p., n.d. Web. 22 Jan. 2018.https://www.youtube.com/watch?v=mZ7bgkFgqJQDVSMarketing. “How Seawater Desalination Works.” YouTube. YouTube, 01 May 2013. Web. 22 Jan. 2018.https://www.quora.com/How-much-does-a-water-desalination-plant-costRedalia Sullivan, Suzanne Maria. “How Much Does a Water Desalination Plant Cost?” Quora. N.p., 30 Mar. 2016. Web. 22 Jan. 2018.