A. Why do we need groundwater resources management in Pakistan?
Groundwater plays a critical role for meeting
irrigation and domestic needs of Pakistan. According to some reports, the
maximum canal-withdrawals are reported to be 105.20 MAF. By assuming 25 % water
losses in our canal system, the net river water delivery at the head of
watercourse commands comes about 78.9 MAF. With similar assumption about the
water losses in the watercourse system, the availability of river water further
reduces to 59.18 MAF at the head of the field-ditch system or farm level. Presently,
groundwater extractions/ abstractions at national level are around 42.6 MAF
available at the stated last community level. This is how we get an overall
ratio of surface / river water and groundwater around 58:42. However, during
the recent drought in the country, groundwater contribution approached to 50 %
to the total water available at the level of field-ditch system.
In case of Punjab, groundwater is the main source of
irrigation water at the head of field-ditch system or farm level. Annual water
share of Punjab, as per the Water Apportionment Accord of 1991, is 54.94 MAF.
With the above stated assumptions about the water losses in canal and
watercourse system, the availability of this share reduces to 31.47 MAF. When
compared with groundwater extraction in Punjab being 34.80 MAF; clearly, the
extracted quantity of groundwater is higher than the canal water supplies at
the field-ditch or farm level (about 52.5%).
If half of the total (provincial)
groundwater extraction, 17.40 MAF, is assumed during winter or Rabi season and then
the surface / river water allocation of 18.87 MAF for the same period is
reduced to the farm or field-ditch level as per the above referred assumptions,
it comes around 10.61 MAF. As the calculated data reveal, the groundwater share
of total water supply in Punjab shoots up to almost 62.0 %.
The above stated situation is what we can
expect during normal years durinf winter seasons but the droughts years, we face even a very scary
scenario for the entire country in general but Punjab in particular. In
2004-05, when Punjab’s canal water share was reported to be 56% less than
normal allocated amount in winter season, groundwater contribution jumped even
higher almost touching a figure of 80%.
For academic understanding, Punjab’s excessive
dependence on groundwater is worth noting: Punjab has 77 % of total area
irrigated in Pakistan but the process of consensus development reduced its
share to only 47.67% as compared to 52.33% water share for the rest of 23 % irrigated area of three smaller provinces in the country.
Obviously, this kind of river water distribution
was not based on population, area irrigated or the in-practice design parameters
of the barrages and canals in the Indus Basin. This was mainly based on the
historic factors as were developed and made reality to live with. This is why
that 89% of total tube-well population,
more than 1.2 million, as reported few years back, is confined to Punjab
to irrigate 71.2% irrigated area that is served by groundwater either conjunctive with canal water or on exclusive basis.
A skewed river water distribution caused too much
dependence on groundwater in Punjab. As Punjab produces almost 80% of
agricultural produce of the country, it can’t be ignored as a provincial issue
only. In a scenario where 70% of pumped water carries sodic hazards, as
reported by Qureshi and Barrett-Lennard in 1998, this will have a huge impact
on the national economy.
If the dominant agricultural production source in
Punjab declines because of the forced application of the unfit sodic groundwater,
its effects will definitely resonate at the national level with a deafening
sound. At present, the revisiting the Water Apportion Accord of 1991 is an
impossible option because of the sustained political sensitivities (though,
with new provinces on the line, it may become an unavoidable outcome anyway),
proper groundwater management is the only option available to focus on for the
survival of the agricultural economy in Pakistan.
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