Every community is going to have its own unique project with some generalizations. Most projects will derive from rainwater collection, using a borehole to get groundwater, or surface water collection as a dam. Each project relies on the community for proper management, storage, and filtration to provide clean water. Proper assessments are necessary to see what the community needs and what will work best. Rainwater collection can be a great source depending on the availability and quality of roofs, the amount of rain during the rainy seasons, and storage.
Thinking about rainwater is a simple concept. Using gutters along the roofs of buildings that pipe the water to a collection tank. A proper roof is necessary to make sure the water quality is almost potable. If a roof is rusted or made of mud, collecting rainwater is not an option. A rusted roof makes it hard to attach gutters to and would need replacement soon anyway. for a project like this to go through, the roof will need to be replaced is not already up to good specs.
Rainwater cannot happen without adequate water. Since rainwater is very seasonal, proper storage is necessary. Many countries have two rainy seasons, a long period stretching for about 4 months and another shorter one for about 2 months. During this period, the rain is intense and usually comes down hard for short bursts. During this time, it is once proper storage is set up, it is easy to collect a lot of water. From our experience in Kenya, 10,000-liter tanks were filling up in 3 days. The question that has to be answered is, " Is that enough water to last the whole year?"
Water collected off roofs is not clean. This is a big misconception because the water is clear. A lot of dust can collect on roofs that are harmful to drink. There are also all the bird droppings on the roof that can be dangerous to consume. The water collected does not need any complicated filtration system but it is necessary. Due to the bird droppings, some sort of filter is needed that gets rid of bacteria. There are many cost-effective filters that are available anywhere that can be used.
Rainwater collection is a great cost-effective way to provide water when the proper conditions are met. There are very few moving parts and can help smaller scale projects work.