**1. Introduction**

We all know that, in order to lead a peaceful life, we are in need of three basic things such as food, water and shelter. The main source of water for all living beings is through the fresh water which has reliable pH and also for the growth of nutritious food through agriculture. Ground water is one among the largest fresh water supply at the world for potable water, irrigation water etc. [1, 2]. At the other hand, Ground water is in need to recharge periodically through recharging methods for the replenishment of resources, since they are available as a limited resource i.e. not in an infinite manner. Hence, for the purpose of avoiding scarcity and to cope up with the need of ground water, it is really essential to recharge the ground water table as it is linked to the water resource sustainability and resilience amidst the changing climatic conditions and demand. For the purpose of planning and managing the sustainability of recharging the water table, it is necessary to consider the conditions

#### **Figure 1.**

*Sprinkler irrigation with groundwater.*

such as total volume, location and timing according to the demand of water. Though the recharge of ground water table is one among the complex process which needs to quantify the requirement in an appropriate manner which is a tedious challenge to meet out at the hydrology. As the quantification of water cannot be done through the already exiting direct measurement methods, hence we need to adopt indirect observations for the purpose of monitoring the processes involved, properties and its quantities.

The water flow that takes place from downhill from surface water to aquifer is known as ground water recharge. This otherwise known as deep percolation or deep drainage. The most common method of recharging the ground water table is through entering the aquifer. The water recharge happens at the vadose zone which is located below the plant roots and is always denoted as flux to water table. At this process, the movement of water from water table into the saturated zone is said to be as ground water recharge. Recharging of water can be done through two methods that is through natural method and through manmade process. Some of the man made process are artificial recharge methods which are carried out through rain water harvesting where the rain water is channeled into the subsurface zone by bore holes.

The ground water recharge has a greater impact while in consideration of various complexities such as climate, land surface and biosphere processes, and characteristics in the unsaturated and saturated subsurface. The components such as Groundwater abstraction, artificial groundwater recharge and irrigation, management of hydraulic structures, infrastructure, and flood management are all manmade variables plays a vital role in the ground water recharge [1, 3]. Hence, for measuring the recharge of water table has been devised through several estimating methods (**Figure 1**).
