Rainwater collection or rainwater harvesting is the accumulation of rainwater which comes from rain drops that fall from the clouds. It is a feasible alternative in sourcing water especially in times where the demand for water exceeds supply. Rainwater adds to the water required for drinking, cleaning the house and the cars and watering the plants. Rainwater collection can be done in many different ways, but they typically fall into two categories: roof catchment systems and ground catchment systems.
One of the simplest means of collecting water is through catchment areas either on the roof or on the ground. A roof catchment system uses gutters installed around the edges of the roof to catch rainwater that falls on the roof. The gutters channel the water to a downspout to transport rainwater to ground level. A thoroughly cleaned drum or barrel or any other container can be put at the bottom end of the downspout to serve as storage of the rainwater. Alternatively, the downspout can be connected to a pipe that leads to a deep well using an elbow joint and other cheap construction materials.
It is advisable that that the first few drums of rainwater be discarded by using it to water plants or cleaning the house to ensure that the succeeding rainwater collected from the roof is relatively clean. The quantity of water intended for drinking must be boiled or treated with a water purifying chemical or tablet to make sure that the water is safe for human consumption. Drums, barrels and other containers that will be used to store rainwater should be properly covered to avoid disease-carrying mosquitoes from breeding and to keep water from contamination that could result in health problems.
Accumulating water at ground level is a more effective method of rainwater collection because the area used to collect rainwater is larger. One of the techniques employed in collecting runoff rainwater is through drain pipes that lead to storage tanks and other types of containers. This method of rainwater collection is more feasible for small communities, but households also can opt for this method of rainwater collection if the construction of the system is cost-effective.
Whatever rainwater collection method is chosen, the output will depend on the amount of rainfall and its frequency aside from the efficiency of the method chosen. Weather patterns in certain regions around the world can change over time, from season to season or from year to year. This might have a negative impact on some households and communities that depend on rain as their main source of water.