What is Groundwater?

The water available within the earth below the ground is ground water.

What is an artesian well?

When ground water seeps into porous layers of rock (an aquifer), which is sandwiched between two layers of non permeable rock, pressure begins to build-up. A borewell drilled through into this aquifer will puncture the ground water under pressure, and the water will shoot upwards to the surface. This is known as an Artesian well.  
 

What are other sources of getting groundwater?

Dug wells, Borewells, Tube wells, Ring wells, Check Dams, Ponds, Lakes, Reservoirs, Springs, Rivulets, Rivers, Streams.

What is a borewell?

A borewell is a well of 6" to 12" in diameter drilled  into the earth for retrieving water.  A borewell is cased in the region of loose subsoil strata open in hard rock. The depth of a borewell  can vary  from 50 feet  to 3000 feet.

How is a  borewell  drilled?

Ancient techniques utilised driving of tubes inside the earth to drill well using mud or water as a liquid media. Then after the invention of diesel engines, rotary drilling was used to remove cores  out of the earth. This was called calex method. Modern techniques use of air compressors and pneumatic drilling equipments, to drill  borewells upto 3000 feet.
 

What is constant water deficit?

Some of the countries in Arabian Peninsula have deserts which receive very less or no rainfall and these countries have acute water shortage and they obtain freshwater by desalination of sea water.

What is the difference between a borewell and a tubewell?

A borewell is drilled with casing pipe put only upto the soil-rock boundary and this is done normally for shallow depths.

In a tubewell, the casing pipes are put upto the bottom of the borewells, with perforation in the pipes in some level. Normally the tubewells are made in desert areas where the availability of water is much below the ground level.

Which are the pumps available for installing in borewells and tubewells?

Jet pumps, Submersible pumps, Compressor pumps, and Hand pumps.

A submersible pump can pump water till what depth?

Submersible pumps are available in 0.35 hp to 200 hp depending upon the size, depth and the yield of the borewell. These pumps can pump-out water from 50 feet to 5000 feet deep and can pump-out 1000 lph to 1 million lph (litres per hour)

How do we find-out the availability of water in the land?

The best way to find out whether water is available in your land is to investigate using any geophysical techniques adopted by a qualified hydrogeologist. Their findings are 80-85% accurate.

Why the borewell fails?

All the locations indicated by a geophysical  survey at their respective locations are interpreted from the resistivity values which are far better than those obtained from the surrounding regions of the area surveyed , these locations contrarily have resistivity values indicative of massive hard rock with absolutely no fractures or seepages of water within them.

Under the conditions of crystallization of basalt, innumerable vesicles are formed, thus creating air pockets within the mass of hard rock, The resistively of these vesicular crystals remain in a similar range as those of soft weathered rock through which seepage of water is likely. Hence, in case pockets of these are encountered a probability of a decrease in yield of the aquifer bodies in the boreholes is possible.

Thus all results are interpreted from a complex natural system of heterogeneous nature. Hence, variations in the results cannot be totally ruled out.

Incase the borewell fails, who does the onus lie upon?

How to select a suitable pump to be fitted in the borewell?

Depending upon the depth of the bore, yield of the borewell and various other parameters like  water requires the head of discharge, a pump is normally decided. The right selection of pump is vital.

Is the borewell water is pure water?

The borewell water is purer than the river or lake water. It will still have dissolved solids and salts and minerals. Most of the borewell water will be hard water. It is advisable to test the borewell water before drinking.