Borewell Recharge: An environment friendly initiative

Water resource is being categorised as a renewable energy source, which means, natural water resources can be easily replenished back to nature. But it is rightly said that overdo of anything is bad; the pace with which natural ground water is being used, or rather exploited, it is not returned to the ground with concurrent pace. This results in depleted groundwater beds which brings havoc at the time of drought and increased irrigation demands.

India’s economy vastly depends upon agriculture. Farmers work for fulfilling the food demands of the population of India along with exporting surplus to the world market. To meet the increasing demand for irrigation and drinking purpose, the borewells are dug with high grade PVC pipes that reach the aquifer where groundwater can be extracted.

Large number of borewells is an issue

The borewells are recklessly drawing water from below the ground. Rainwater is the only option available for reviving the depleted ground water but this natural process of rainwater seeping under the ground through fixtures and cracks is a very slow process. Research shows that only 5–10% of seasonal rainfall infiltrates into groundwater in the hard-rock regions. Also, in case of scarce rainfall, there isn’t enough water being renewed underground. Water and environmental conservationists brainstormed and came to the solution called Borewell recharge. The idea was simple; develop and employ the methods to store rainwater and then channelize the stored surface water directly towards the aquifer using borewells.

Recharging the Borewell

Borewell recharging technically focuses on the use of harvested surface water (obtained via rainfall or nearby water bodies) where runoff water begins to pass through a natural filter made up of large and small stones. Then, there is another layer of sand through which water passes and finally, it perforates in the borewell pipe via a fine mesh which is wrapped around the drilled casing pipe. The fine mesh ensures the removal of big and tiny impurities before the water enters the borewell.

There are two borewell recharge methods being employed by farmers across India :

Direct Recharge –

In the direct recharge method, a

• percolation pit, usually 10×10 feet, is dug around the tubewell’s casing pipe.
• This casing pipe is then perforated with a drill machine and the holes are covered by a nylon mesh. The mesh ensures nothing, but the water goes across the borewell.
• Now the pre-casted RCC (Cement) rings are placed around the borewell casing through which the harvested water would seep to reach the nylon mesh of casing pipe and proliferates into it through its holes.
• The empty area between the walls of well and rings is then filled with filtering materials like sand, gravel, crushed stone, jelly and such others.
• The rain water from adjacent water body such as a catchment pond is diverted into this well, it gets filtered and then continue to seep into the casing pipe, thus refilling the bore well.

Direct Borewell recharge is recommended only if the borewell has run dried or is yielding a negligible amount of water. Even a running borewell can practice direct recharging in case of surplus surface water which otherwise would go down the drains and get wasted. Though letting unfiltered surface water to seep into the ground is highly discouraged as this may contaminate the ground water or clog the aquifer with impurities such as toxic minerals like fluoride and industrial chemical waste.

Indirect Recharge

Indirect method of borewell recharge includes the following,

• Instead of digging the pit around the casing pipe, it is dug within a 20 feet radius, maintaining a minimum distance of 3 ft between the recharge well and the borewell.
• Just like the direct borewell recharge method, the casing pipe too has holes covered with nylon mesh and the well is filled with filtering materials for water to seep in while leaving chunked impurities at bay.
• Here, in indirect borewell recharge, the water flows through the ground, reaches the pipe and then seeps in though nylon mesh and casing pipe holes.

Indirect recharging works best for well-functioning borewells which haven’t gone dry yet. This is to ensure continuous availability of the surface water in case of dry seasons of the year.

Why Direct Borewell Recharge is advocated

The sophistication process of direct borewell recharging method has led to the availability of desired quality of ground water which is fit for irrigation as well as drinking. The advantageous implications of this method are listed as under:

• There is a well amounted reserve of water for urgent need during highly dry times of the season. Even the most dried up borewells can be filled up using this method.
• This simple mechanism of filtering surface water and pushing it into the ground is easy to understand by general population.
• It is environment-friendly if carried out with care.
• Harvesting rainwater which is a pure form of water can lead to sustainable output of an aquifer with lesser impurities being reaching the ground water level.
• This method prevents adverse social impacts like displacement of population or loss of agricultural land.
• As compared to other methods of storing surface water, this method minimizes the amount of water loss due to evaporation, thanks to its close knitted design for collecting and transporting water to the borewell.

Before you take on Borewell recharge

Borewell recharging undoubtedly is one of the best initiatives of 20^th century. In order to extract 100% benefits of this process, certain pre-recharging research becomes inevitable

1. Aquifer Management

Some public initiatives of recharging the borewells goes ineffective due to lack of scientific understanding of groundwater. Before putting up with this process, one must have appropriate knowledge of the potential of their groundwater aquifer.

An approach called Aquifer mapping is a scientific method determining the quantity and quality of groundwater in a particular area. Aquifer mapping can help in

• deciding the depth of recharge wells that can provide maximum recharge and maximum utilization of harvested water.
• finding the recharge rate of an aquifer. This helps in deciding optimum number of recharge wells required for a given aquifer.
• locating the natural recharge and discharge areas
• defining how much water can be extracted and for how long.

2. Stream Pollution

Due to unchecked effluents from urban and industrial areas, stream pollution has become a matter of high priority. Measures must be implemented to ensure that the harvested water which is used for recharging the borwells must be free from water pollutants, especially in case of using a direct borewell recharge method. This is necessary to take care so that groundwater does not pose any health and environmental risks to the population.

3. Local legal framework

One must read and understand the legal regulations laid by central or state authorities for the area where recharging is intended to be done. This prevents unnecessary chaos and wastage of resources due to non-agreement.

Borwell recharging products by Chaitanya Products

CHAITANYA RAIN HARVEST PRODUCTS & SYSTEMS PVT. LTD. specializes in number of rain harvest products and services under one roof. The company provides most modern filtration systems for rainwater harvesting named as APOLLO Vee-Wire Filter Screen Kit. They are the sole distributer of this product.

Apart from Filter screen kit, the other basic products needed for rainwater harvesting are readily made available here. These include

Fibre-reinforced plastic (FRP) Roof rainwater drainage gutters

Company is an authorized distributor in Maharashtra for Hycount Group of Industries for U Channels Pipes and fittings. Hycount Group is the Only Pipe Manufacturer in India who has Won the RAJIV GANDHI QUALITY AWARD (Highest Award for Quality in the Country) thrice in a row.

They also deal in Gravels used for filling the borewell pit and other RWH systems. Gravels size ranges from 5 mm to 10 mm. Precasted RCC Hume Pipes collar rings are available in 3 feet, 4 feet and 5 feet outer diameter sizes.

Not just products, the company can also be relied with Rainwater Harvest Services. The services include preparation of rainwater harvesting reports, designing rainwater harvesting layout, designing detailed engineering drawings, conducting hydrogeological and borewell surveys and providing feasibility reports.