One of the most basic types of rainwater harvesting systems; water Butt collects rainwater in a container from natural rainfall and/or drain pipes. The collected water is used mainly for watering the garden.
Another very common and professional type of rainwater harvesting.
Most rainwater harvesting systems need pumps to transfer the collected rainwater from storage tanks to the point of use. Submersible pumps are generally more efficient than suction pumps and do not suffer from the same limitations.
This type of rainwater harvesting system doesn't rely on gravity to supply water to the outlets. Instead, it pumps the harvested water to a tank which can be at any level in the building. Furthermore, a booster pump is used to provide a pressurized water supply. One of the most significant benefits of this system is that it offers great flexibility to tailor the booster pumps to adjust the flow and pressure requirements of a building.
This system ensures water is supplied to the outlets by gravity alone. For this, the harvested water is first pumped to the header tank, i.e. high-level tank and then allowed to free-flow. In Indirect gravity systems, the pump works only to fill the header tank.
In few conditions, a system which functions purely through gravity may be needed. Such systems do not demand pumps hence involves no energy use. With such an arrangement, water can be collected only when collection tanks are located below the level of gutters, yet higher than the outlets which it will supply. Here the only power of gravity is needed to feed collected and harvested water to various parts of the household. Gravity only is one of the most energy-efficient rainwater harvesting systems.
Retention ponds are used to collect surface runoff water and improve the quality of water by natural processes like sedimentation, decomposition, solar disinfection, and soil filtration. This type of pond normally has a mud bottom, but in some cases, it may be lined with concrete. The most common use of water collected and harvested by pond harvesting is watering livestock, however, it can also be used for groundwater recharge, irrigation or any other purpose other than potable uses.
Underground storage tanks are very popular in areas where the majority of rainfall occurs in one single season. These underground tanks are insulated and have a very low rate of evaporation. In addition, the water stored in these doesn't freeze if it is buried below the frost line, this is a huge advantage that surface storage tanks do not offer. Underground tanks need to be connected to an electric pump to ensure supply of the stored water to the outlets.