How many tube wells are there in Bangladesh?

This is an important issue because over 165,000 deep tubewells have been installed throughout Bangladesh to reduce exposure to As [14].

Why were tube wells dug in Bangladesh?

Last year scientists concluded that arsenic entered the water in tube wells as a result of thousands of ponds that were dug across Bangladesh to provide soil for flood protection. Disturbing the ground released the organic carbon, which in turn causes arsenic to leach from sediments.

What is the use of tube well?

Tube-well water is used primarily as a source of drinking water by the vast majority (90%) of the rural population in Bangladesh (16). A tube-well is a small-diameter cased well fitted with a cast iron suction hand pump (1).

Which tube is well?

A tube well is a type of water well in which a long, 100–200 millimetres (3.9–7.9 in)-wide, stainless steel tube or pipe is bored into an underground aquifer. The lower end is fitted with a strainer, and a pump lifts water for irrigation.

What are the disadvantages of tube wells?

The main disadvantage of using tube well systems for irrigation purposes is that it leads to depletion of the groundwater because of which the groundwater stock or pool may get exhausted and ground water is only used as a source.

How much does a tubewell cost?

cost of tubewell installation and the cost of maintenance are also very high and on average costs Rs. 1,46,000 and Rs. 3,000/ha, respectively (Table 7).

Why is arsenic so high in Bangladesh?

Sources of Arsenic in Groundwater in Bangladesh But it is now widely believed that the high arsenic levels in the groundwater in Bangladesh have a natural geological source which may be due to abstraction water from quaternary confined and semi-confined alluvial or deltaic aquifers.

Is the water in Bangladesh safe?

Bangladesh has made significant progress regarding universal access to improved water sources, with more than 97 per cent of the population having access in 2013. But access to safe drinking water is still low at 34.6 per cent. Also, more than 41 per cent of people drink water from sources with faecal contamination.

Why is tube well expensive?

(i) Excessive use of tubewell water can lead to depletion of groundwater. (ii) It is useless if the water is brackish. (iii) It is expensive as it requires continuous supply of electricity.

How do you purify water from a tube well?

You can boil the well water for 5 minutes. With this, all the bacteria inside it will be eliminated. However, boiling will not be able to remove the solids and other materials inside the well water. The use of chlorine drops or iodine tablets can effectively kill the bacteria in the well water.

Why tube wells are better than wells?

Two advantages that tube wells have over surface wells are: Tube wells can irrigate larger areas than surface wells. They can supply water even during the droughts as they can draw water even from great depths.

What are the advantage and disadvantage of tube wells?

Advantages: Tube wells do not result in evaporation of water like suface wells. It irrigates large area (400 hectares). Disadvantage: However tube wells are only possible in areas where the groundwater level is not too low power is needed to drain water.