Rainwater harvesting is the process of accumulation and storage of rainwater for reuse rather than allowing it to runoff and turn useless.
The different methods of rainwater harvesting include:
- Rooftop rainwater harvesting
- Surface runoff harvesting
- First, flush
- Transportation
- Catchment
- Filter
Rainwater harvesting is a sustainable process that helps in preserving water for future needs. Water scarcity is a major concern in today’s scenario. The process of rainwater harvesting is a good way to conserve water.
Rainwater harvesting systems consists of the following components:
- Catchment- Used to collect and store the captured Rainwater.
- Conveyance system – It is used to transport the harvested water from the catchment to the recharge zone.
- Flush- It is used to flush out the first spell of rain
- Filter – Used for filtering the collected Rainwater and remove pollutants
- Tanks and the recharge structures: Used to store the filtered water which is ready to use.
The process of rainwater harvesting involves the collection and storage of Rainwater with the help of artificially designed systems that run off naturally or man-made catchment areas like- the rooftop, compounds, rock surface, hill slopes, artificially repaired impervious or semi-pervious land surface.
Several factors play a vital role in the amount of water harvested. Some of these factors are:
- The quantum of runoff
- Features of the catchments
- Impact on the environment
- Availability of the technology
- The capacity of the storage tanks
- Types of the roof, its slope, and its materials
- The frequency, quantity and the quality of the rainfall
- The speed and ease with which the Rainwater penetrates through the subsoil to recharge the groundwater.
The advantages of rainwater harvesting are:
- It is cost-effective
- Conserves water
- A source of water for landscape irrigation
- It is a simple method and easy to practice.
- It reduces soil erosion and pollution of water bodies due to fertilizers and pesticides.
The benefits of rainwater harvesting system are listed below.
- Less of cost
- Helps in reducing the water bill
- Decreases the demand for water
- Reduces the need for importing water
- Promotes both water and energy conservation
- Improves the quality and quantity of groundwater
- Does not require a filtration system for landscape irrigation
- This technology is relatively simple, easy to install and operate
- It reduces soil erosion, stormwater runoff, flooding, and pollution of surface water with fertilizers, pesticides, metals, and other sediments.
- It is an excellent source of water for landscape irrigation with no chemicals and dissolved salts and free from all minerals.
The Disadvantages are:
- Regular Maintenance is required
- Requires some technical skills to install
- Limited and no rainfall can limit the supply of Rainwater
- If not installed correctly, it may attract mosquitoes and other waterborne diseases.
- One of the significant drawbacks of the rainwater harvesting system is storage limits.
How much does it cost?
When a community comes together to harvest rain, the per-capita investment goes down. For instance,
Panchsheel Park Colony about 1000 residents pooled in
Rs 4.5 lakh to harvest more than 170 million liters of water annually.
Read further thread for more information .....http://www.rainwaterharvesting.org/urban/Costs.htm