What Is a Borewell?

A borewell is a narrow shaft that is bored into the ground 100 to 1500 feet deep. A 6 to 12-inch PVC pipe is used to bring the water to the surface using a pump. Bore water comes from groundwater that has seeped into the ground and is stored in underground aquifers.

There are both deep and shallow borewells. In shallow borewells, the contamination can be high because the water is not protected from defecation, pesticides, pathogens, and other substances. It is often not fit for drinking without significant water treatment and purification. However, bore water may be used for other watering needs like livestock, toilets, showering, watering gardens, washing cars, etc. It is wise not to water edible plants with borewell water unless it has been tested or treated.

Water from deeper, confined aquifers generally gives higher quality water; Regardless, it is wise to test water often to make sure it is safe for drinking or use in cooking.

While borewells can be contaminated with natural sources like bacteria, minerals, and viruses, human activity likely has a greater impact on the contamination. Oftentimes, fertilizers, pesticides, insecticides, poorly maintained septic tanks, and fuel and chemical leaks cause more contamination to borewells. Some of these contaminants are very concerning, like nitrate, pesticides, arsenic, and petroleum products.

Borewells in Asia

It is estimated that there are tens of millions of wells and borewells are in South Asia alone, with over 50% of those being borewells.² The World Bank says South Asia accounts for nearly half of the global groundwater used for irrigation.³ This has caused non-renewable depletion of groundwater levels and a significant concern regarding the quality of drinking water. This depletion is caused by large-scale automated pumping of groundwater rather than hand-operated pumps, meaning it is usually poor rural villages that suffer the most.