As a part of its pioneering drinking water project, the Nice Link Trust has established eight solar desalination plants at Ibrahim Haidry and Rehri for purifying municipal water for potable use. Sponsored by the Federal Republic of Germany, the project is essentially meant for people inhabiting coastal regions, who lack access to potable water.
According to a Recorder Report, the project is being funded with a $21 million ADB grant for water treatment in coastal areas of Sindh, particularly in Thatta and Badin where drinking water scarcity has assumed alarming dimensions. Large areas of the province, including Thar, Nara, etc contain groundwater of extremely poor quality. In Tharparkar, the situation has become further complicated due to the presence of high flouride in groundwater in some areas. In Balochistan, the Makran coastal zone and several other basins contain highly brackish groundwater, which is practically undrinkable. Experts believe that inexpensive drinking water can be made available to the communities inhabiting these far-flung regions by setting up strategically located desalination plants operated by solar energy. If the project proves to be a success, it can be replicated in other water-scarce coastal regions.
AS FAR AS QUALITY OF DRINKING WATER IS CONCERNED, EXPERTS OFTEN DIVIDE PAKISTAN INTO FIVE MAJOR ZONES: sweet groundwater areas where water is easily accessible for human consumption; the brackish groundwater areas where canal or river water is available; the mountainous areas in the north where spring water is frequently available; the coastal belt where saline water is generally available only at a greater depth; and the coastal belt where saline water is available in abundance.
Incidentally, about 28 percent of the area in Sindh has fresh groundwater which is suitable for irrigation. Here fresh groundwater can usually be found at a depth of 20 to 25 meters. However, what is particularly worrisome is the rapid receding of the groundwater table, the speed of which has been calculated at one meter to 10 meters a year! This means that groundwater may soon become extinct if the causes responsible for the phenomenon are not addressed on an emergency basis.
Meanwhile, the per capita availability of fresh water in Pakistan has dropped from 5,600 m3 to 1000 m3, which represents over five-fold reduction. The quality of groundwater and surface water too has undergone deterioration to an alarming degree, largely because of unchecked disposal of untreated municipal and industrial wastewater and the excessive use of fertilisers and insecticides in agriculture. According to a study, about 70 percent of the 560,000 tubewells in Indus Basin are pumping water affected by salinity. And surface water from most of our rivers too has become highly polluted, thanks, largely to the dumping of untreated industrial and municipal waste into water channels.
If solar power is made available for desalination of seawater, the shortage of drinking water in far-flung areas of the country (such as barren lands of Balochistan, and desert areas in Sindh) can be eliminated. This can be done by pumping seawater to remote areas, treating it with solar energy-operated desalination plants and pumping it to coastal villages and other habitations as drinking water. Alternatively, seawater can be desalinated near coastal areas, and untreated water thrown back into the sea and the treated water supplied to small towns and villages with the help of pumping stations. This process can ensure not only availability of abundant drinking water, it can also provide employment to the local inhabitants.
(The salt obtained from this process can be used in commercial and industrial applications.) Pakistan already has a small experimental desalination solar energy-operated plant near Gwadar. It is said that this plant was designed and manufactured by PCSIR. This means that aside from utilising foreign desalination expertise, the government should encourage local expertise as well to cut down the manufacturing and installation costs. It will be possible then to replicate the Nice Link Trust project on a much wider scale.
Comments
Comments are closed.