Rainwater Harvesting System

    With increasing population and climatic changes, it has become important to understand that the resources we have are not going to support us for long. So, it is high time that we start conserving water. One of the effective ways to conserve water is Rainwater Harvesting. The process of collecting and storing rainwater and utilizing it with or without treatment for various purposes like cleaning, gardening, recreation activities, agriculture, washing, etc. is known as Rainwater Harvesting.

 

Rainwater harvesting system is not a new technology; it is an ancient legacy. It is nearly impossible to trace back to which civilization used the method of rainwater harvesting first, but evidence shows that different types of rainwater collection systems were used in 2000 BC in India, Mesopotamia, China, and modern-day Israel. Similarly, on the tops of hills and mountains of Nepal, ponds were dug in ancient times to collect rainwater mainly for livestock use. In the towns, ponds and stone spouts were constructed and these were the main sources of water before the introduction of piped water supplies. With such a great history and its importance as a source of water, this system needs to be used extensively with modern modification in the technological part.

Rainwater Harvesting system can cope with the water crisis problem to a great extent as rain is a major source of water so that enough water can be collected. Following are the major advantages of the Rainwater Harvesting system;

·       Safe-It provides safe and sustainable water as rainwater is naturally pure and fresh except the first spell of rainfall as it contains a relatively larger amount of pollutants.

·        Cost Effective-There will be a significant cost saving for the community and each household as after installation cost there are not many expenses in this system.

·        Eco-friendly-Rainwater Harvesting system results in reduced energy consumption and less greenhouse gas emission and not much power are used for transmissions and treatments.

·       Stormwater Management-It minimizes the requirement of huge size storm drains which save a lot of construction and maintenance costs.

·     Conveniences-Inconveniences caused due to irregular supply of municipal water are extensively reduced with this system.

·        Irrigation-Water so collected can be properly used in dry periods for agricultural purposes which results in increased production.

·        Reduced floods-The quantity of storm water will reduce resulting less chances of floods.

·        Livestock-Another great use for rainwater harvesting is feeding farm animals and livestock. Either for smaller farms, homesteading, or even large-farm applications.

 

Broadly there are mainly two methods of harvesting rainwater;
 

1.    Roof-top Rainwater Harvesting: In this system, the roof acts as a catchment, and rainwater is collected and transited to the storage tank via conduits (pipes).

2.  Surface Runoff Harvesting: In this method, surface runoff (excess rainfall) is caught and used mainly for recharging aquifer.

Components of Rainwater Harvesting System;

A Rainwater Harvesting System comprises components of various stages-transporting rainwater through pipes or drains, filtration, and storage in tanks for reuse and recharge.

Common components are;

1.    Catchment: It is the surface that receives the rainfall and provides water to the system. The rooftop of a building can be taken as an example of a catchment.

2.    Coarse Mesh: It is provided to prevent the passage of debris.

3.    Gutters: Simply, gutters are the channels (drains) provided at the edge of the sloping roof to collect and transport rainwater to the storage tank via conduits.

4.    Conduits: Conduits are pipelines or drains that carry rainwater from the catchment or rooftop area to the storage tank.

5.    First Flushing: The first spell of rain carries a relatively larger amount of pollutants from the air and catchment surfaces which need to be spelled out. For this, a valve is installed in the system which spells out the first spell of rainwater. It could be manual or semi-automatic.

6.    Storage facility: It is a tank which could be of different shape and can be made of concrete, brick or industry made plastic or steel tanks can be used.

7.    Recharge Structure: Excess rainwater can be charged into groundwater aquifers through any suitable structure like dug walls, bore-wells, recharge trenches, etc.

 

Rainwater Harvesting is an effective way in solving the problem related to the water crisis and upgrading the overall quality of living. So, proper regulation must be made for the compulsory installation of Rainwater Harvesting system in every building.