What is Rain Water Harvesting?
Rain water harvesting
literally means capturing and collecting rain where it falls. Also, capturing and collecting the run off in your place is a part of the rain water harvesting. Necessary and adequate measures should be taken to keep the collected rain water clean. This is ensured by barring any polluting activities near the catchment area. Rain water harvesting is one of the most effective and simplest ways to conserve water. Hence, to know more about the technique, rain water harvesting, read on the following article.
The principle behind rain water harvesting is capturing and using the rain water from a catchment area. This technique is currently enjoying a sort of renaissance. Actually, the apparatus for rain water harvesting existed 4000 years ago in Greece and Palestine. So, the technique is in existence for a very long period.
Ways of Rain Water Harvesting
There are different means of water harvesting that can be undertaken to successfully capture the rain water for later purpose. These different ways include:
- Conserving the rain water implementing watershed management
- Capturing and collecting seasonal flood waters from the local streams
- Capturing and collecting run off from local catchments
- Capturing and storing run offs from rooftops
Techniques of Rain Water Harvesting
Two main techniques exist for rain water harvesting. These are:
- Recharge to groundwater
- Storage of rain water in catchments surface for later use
Recharge to groundwater is completely a new concept when compared with storage of rain water in catchments surface. The later is a traditional method and implements structures like weirs, check dams, ponds, underground tanks, etc. Recharge to groundwater uses structures such as:
To recharge shallow aquifer, these recharge pits are constructed. They are 1-2 meter wide and 3 meters deep.
If a permeable stream is present at a shallow depth, then trenches are constructed. These maybe 0.5-1 m wide and 10-20 m long. The depth is around 1-1.5 m.
Dug wells that are already present can be used as a recharge structure.
To recharge the deep aquifers, these wells are constructed. They usually have a diameter of 100-300 mm.