Two reports, 2 decades apart, predicted Punjab’s desertification in 25 years - MonsterThinks
Why they are both right
Punjab is drawing more water than is being replenished, as a result of which the water table is going down.
The Punjab Vidhan Sabha committee constituted to study
water table depletion, has recently said that the state will turn into a desert
in the next 25 years if the present trend of drawing water from underground
aquifers continues.
This is a prediction that has been made before – over two decades ago, a study on water table depletion in Punjab had projected almost the same time frame of 25 years, saying aquifers in Punjab could be depleted by 2025.
How alarming is the water situation in Punjab really? Could both reports be accurate? We explain.
What is the report from two decades ago?
According to Central Ground Water Board (CGWB) officials, the study was titled ‘The State of the World Report, 1998′, published by the Washington-based World Watch Institute (WWI). It said Punjab’s aquifers could be depleted by 2025.
Why will the land of five rivers (now 2.5 rivers after the Partition of Punjab) turn into a desert?
Out of 138 blocks in Punjab, 109 have already gone into the ‘dark’ or over-exploited zone, which means groundwater extraction is more than 100 per cent here. Two fall under the ‘dark/critical’ zone (groundwater extraction is 90 to 100 per cent), while five are under the semi-critical (groundwater extraction 70 to 90 per cent) zone. This means that around 80 per cent of blocks of the state have already dried up and four per cent are on the verge of it.
Only 22 blocks, which are located in South West Punjab and the Kandi area, witnessed a rise in the groundwater table in the past two decades.
However, this is not good news, because the water in most such blocks is either
saline or brackish, fit for neither irrigation nor human consumption.
Experts said that water availability at 3 to 10 meters,
which needs a centrifugal pump to extract water, is the most desirable, but
currently, water is available at 20 to 30 meters, or more than 30 meters down,
in around 84 per cent of Punjab. This needs tubewell or submersible pumps for
extraction, and farmers are spending huge amounts to get deeper and deeper
wells, leading to financial liabilities.
Why is Punjab over-exploiting its groundwater?
Because of the adoption of a faulty cropping pattern.
With the advent of the Green Revolution in the state in
1966-67, paddy, historically never the main crop of Punjab, was adopted on a
large scale. The area under it increased from 2.93 lakh hectares (LH) in
1966-67 to 31.49 LS in 2020, which was the highest-ever area under rice
cultivation in the history of Punjab. This is an almost 11-time increase in
rice area in five decades.
“We sacrificed this precious, natural resource to paddy crop, which also hampers water recharging because of the puddling method used to prepare fields for transplanting. Puddling has created a thick hard layer on the agricultural fields, disturbing the recharging system and wasting rainwater in evaporation or creating flash floods,” said a senior research engineer, department of soil and water engineering, Punjab Agriculture University (PAU), and Chief Scientist in All India Coordinated Research Project (AICRP).
How to explain the two 25-year predictions
Experts said the calculation of 25 years was relevant two
decades back as well as today.
They said water was then available at a depth of 3-10 meters
in most of Punjab, barring a few districts where it was up to 20 meters deep.
But now it is not available at this depth in 84 per cent of the state, which is
a desert-like situation as we can only get water through deep tubewells.
In the three decades (1966-67 to 1999) of the Green revolution,
with the paddy area increasing from 2.93 LH to 26.12 LH by 2000, the water table in
73 blocks (53 per cent) of Punjab slid into a dark/overexploited zone by 1999, as
per a CGWB report. Paddy takes at least 4,000 litres of water to grow one kg of
rice. The 1998 report estimates that by this calculation, the remaining half of
Punjab will also slip into the dark zone in the coming 25 to 27 years if
control measures are not taken.
“It is true also because, in almost two decades from 1999 to
2017, the number of dark/overexploited blocks had increased from 73 to 109. If
seven critical and semi-critical blocks are added, the number comes to 116
blocks,” adding that it puts a big question mark on the
sustainability of agriculture.
Talking about VS Committee’s report, a former
professor of industrial and production engineering at NIT Jalandhar, said that
instead of taking it literally, one should see it as an indication of the
magnitude of the threat of Punjab’s water table is facing. “In a couple of decades, we
have dried up our upper aquifers. This could happen to deep aquifers too, and
then Punjab will be like another Rajasthan. It is high time we stop mindless
extraction and replenish our water,” said Singh.
“Farmers must be incentivised to choose cropping patterns that require less water, and go for drip irrigation or other water management mechanisms to save our only available deeper aquifers,” Singh added.
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