Rainfall: You can collect and store rainwater. It is usually pure enough for drinking, cooking, and bathing. Beware, however, of the chemical contaminants in “acid rain. “[1] X Trustworthy Source PubMed Central Journal archive from the U. S. National Institutes of Health Go to source Groundwater: You can collect water from underground using a tube well or a pump machine. This is usually pure water, although chemicals and bacteria can seep into the water table and contaminate this source. From a lake or pond: you can collect water from ponds, but this water is not usually potable. It must be purified before drinking. You can, however, use it for watering or irrigation purposes. From a river/canal/sea: This water can be used for irrigation. This is big source of all water of our daily use. Water from air: By applying new technology we can get collected water from air. This may be a very small amount, but it could be useful in some circumstances.
Apart from standard outside water use, grey water can also be used in cooling your house and filtration for more drinking water.
Roof catchments: This can be done on schools, public offices, etc. However, a monitoring plan should be put in place regarding quality, and on the amount of water harvested and used. Storm water storage and urban parks: Stormwater storage can be developed in a mid-sized urban park to harvest storm water for use during dry seasons after being treated and also for fire fighting not forgetting urban agriculture. Reclamation of waste-water: The possibility of reuse of waste-water should be considered, e. g for irrigation purposes.
You can also wait overnight and gather some water from the morning dew. Try finding a smooth, light surface—like a large plastic board—so that the dew can simply slide off into a leak-proof container.
The main idea here is to reduce your water use. Avoid washing your car, minimally water your lawn or shrubs, and practice alternative methods of waste disposal.
A good rule of thumb is: if you have a one thousand square-foot roof area and have it all guttered and piped into a rain holding tank, you should gather 600 gallons (2,000 L) from a 1” rainfall event. Metal roofs are best, but shingle roofs can work fine. Most folks will design in a “first flush” device that routes the first 20 or so gallons of run-off into a separate small tank. This “first flush” rainwater will contain dust, bird droppings, small leaves, etc that you don’t want to get into your main holding tank. [9] X Research source But if not, these items will settle to the bottom of your holding tank and won’t be a big problem. Most rain tanks have a 2” threaded hole on one side just above the bottom of the tank, so you can attach a hose, or a pump to pump for a distance uphill. You can gravity feed from the bottom of the main tank into your system for garden watering. You can also use a small 12 volt electric, “on demand” pump. Think about how to protect this pump and piping if you live in a cold climate.
For example: if you want to water a garden and you have no restrictions on having a collection system, then you might just want to have some 20–40 gallon (75. 7–151 L) drums with a spigot at the bottom. Support the drums with cinder blocks. You can hook this up to standard rain gutter collection system). If you want to be more ambitious—say, a water feature and then some—then you will need: a larger container to accommodate the larger amount of water (or many small containers that make a large system); better supports (a small, reinforced slab); a larger amount of area covered for to gather water; and some pumps.
