The amount of water collected from rain in a year in the world is difficult to estimate, as it varies greatly depending on the amount of rainfall in different regions. However, a rough estimate is that about 100 trillion gallons of water are collected from rain each year.
This amount of water is equivalent to about 10 times the volume of Lake Erie. It is enough to meet the annual water needs of the entire world population for about 7 years.
However, not all of this water is available for human use. Some of it is lost to evaporation, infiltration, and runoff. In addition, much of the water that is collected is used for irrigation, industrial purposes, and other non-drinking water uses.
As a result, only a fraction of the water that is collected from rain is actually available for drinking water. In some places, the amount of available drinking water is very limited. This is a major problem in many parts of the world, and it is one of the challenges that we will need to address in the future.
Here are some ways to collect rainwater:
- Rainwater harvesting: This is the practice of collecting rainwater from roofs, catchment areas, or other surfaces and storing it for later use. Rainwater harvesting can be used for a variety of purposes, including drinking water, irrigation, and livestock watering.
- Rainwater cisterns: These are large tanks that are used to store rainwater. Rainwater cisterns can be made from a variety of materials, including concrete, plastic, and metal.
- Rainwater barrels: These are smaller containers that are used to collect rainwater. Rainwater barrels are often used for watering gardens and plants.
Rainwater harvesting is a sustainable way to collect water and reduce our reliance on municipal water supplies. It is also a way to improve water quality and reduce pollution. If you are interested in rainwater harvesting, there are many resources available to help you get started.