Nimra Hamayoun, Green Blogger

“Water is not only for life, water is life.” This quote by the United Nations Secretary-General. The critical status of water is threatening that effect all aspects of human life. It is one of the development challenges so that the Sustainable Development Goals (SDGs) place great emphasis on ensuring accessibility and sustainable management of water.  

1.Water resources in Pakistan: 

Most of Pakistan’s area is situated in the arid climate zone, where the average rainfall is below 200 mm per annum and the availability of groundwater is inadequate to fulfill our needs. (Alamgir et al., 2016). Groundwater withdrawal is the most common anthropogenic activity related to the Earth’s subsurface (Benejam et al., 2010). The groundwater extraction considerably increased after 2010. The over extraction of groundwater has led toward water shortage and a smaller accessibility of drinking water.

2.Amount of Rainfall and Number of Rainy Days in Sialkot:  

The trend for the total rainfall amount during the season and total number of rainy days during a season both are increasing. It is evident from the graphical display that when the cumulative value of rainfall for a particular year increases, the total number of rainy days also increases. The direct relationship between the amount of rainfall and number of rainy days is very well justified.

3.Rainwater Harvesting:  

Rainwater Harvesting, a well-known technique that has been used for hundreds of years. It is a method for saving and accumulating rainwater from various elements such as surface runoff, rooftops, and other catchments. However, there is no proper definition of the term ‘rainwater harvesting ‘commonly accepted by the scientific community. Researchers use a wide variety of definitions and terms to describe that the various methods aimed at using, collecting and storing rain runoff in order to increase the availability of water mainly for agricultural and domestic uses in arid and semi-arid areas . 

4.Methods and Systems of Rainwater Harvesting: 

4.1-Wet System 

 In this method the pipes are located underground the storage tank and the pipes remain full of water, so it is known as “wet” system. With this method, several pipes are connected to several plugs on the building and routed underground into an empty storage tank. In the absence of rainfall, the water level remains constant. However, it is advised that pipes be watertight to avoid leakage into the soil because the pipes are always full of water. This is one of the most expensive method due to underground piping.

4.2-Dry System 

 It is an upgraded version of the rain barrel system, in this technique a container larger than the rain barrel used that usually located a few meters from the property. The roof gutter is directed into the storage tank by with the help of PVC pipe. 

This system is known as “dry” system because, the pipes get dry after rainfall because all the water drains into the top of the tank. The benefit of this method is to prevent from flooding in case of heavy rainfall because of larger storage tank and it is easily implemented and inexpensive to install. This system is particularly ideal for stormy areas. 

4.3-Rain Barrel 

 The rain barrel is commonly used on household level because barrels are easily available and cheapest Rainwater Harvesting system. In this system barrels installed beneath the roof drainpipe so that all the rainwater falling on the roof will be funneled and guttered into the barrel. The barrel usually plugs at the bottom by using tap which makes it possible for water to be used easily. 

5. Advantages of Rainwater Harvesting System:  

Rainwater harvesting is part of sustainable developmental techniques and it is bringing a lot of benefits, not just for users but also to government and environment. In short, Table 1.7 shows some of the advantages from rainwater harvesting system.

Advantages of Rainwater harvesting system for users, government, and environment




      Rainwater is relatively clean, independent and sufficient water supply.

      Save money by reducing the volume of water purchased from public systems.

      Rainwater Harvesting system uses simple technologies that are

easy to maintain and inexpensive.

      Reduce the burden on groundwater.

      Save money by extending the life of plumbing fixtures and appliances.

      Reduction in electricity bills.

      Rainwater harvesting system is very easy to implement and handle.


         Reduce the burden for new investment to replace the old systems and adding the water supply infrastructures.

         Rainwater harvesting system can reduce  construction cost in  each development  because it can be easily built during new  construction or  established to an  existing structure.

         Potentially avoid the cost of accessing public water systems when it is not economically feasible.





·          Enhance soil moisture                       

           levels for urban greenery.  

·          We can significantly 

            reduce our reliance on    


·          Avoid ecological damage

·          By capturing rainwater, we reduce the chance of


·          Rainwater harvesting system save our precious resources of water.



About the Author: Nimra Humanyoun is a passionate environmentalist, a green blogger and social worker. She has her keen interests in making this world a greener and cleaner place.