Lake Manchar is dead

Pakistan's largest freshwater lake is drowned by effluents

 
By SHAHID HUSAIN
Last Updated: Sunday 07 June 2015

Lake Manchar is dead



Located 18 kilometres west of Sehwan in Dadu district of Sindh and 300 kilometres north of Karachi, Manchar is a vast natural depression surrounded by Khirthar Range hills in the West, the Lakki hills in the East and a flood embankment in the Northeast. It is Pakistan's biggest freshwater lake; some even say it is Asia's biggest lake, though that is debatable. But today it would be more apt to describe Manchar as a grim cesspool of agricultural effluents, including pesticides.
How did that happen? The lake's misfortune can be traced back to 1982, when Pakistani authorities remodelled the Main Nara Valley Drain: built in 1932 by British colonialists to control floods in the Hammal Lake in southern Sindh and to protect the low-lying areas of the province, the water body was now turned into a drain to carry industrial runoff and agricultural effluents into the Arabian Sea. But then how did that affect the Manchar? The remodelled drain -- now called the Right Bank Outfall Drain -- did not work and was redirected to Manchar. The authorities assumed that freshwater from the Indus and from the torrents that gush down the Kirthar hills during the rainy season -- the two sources of the lake -- would dilute the effluents. That was a big mistake. For, Manchar's two sources don't provide it enough water to clean effluents. Flows from the Indus are drying up because of barrages and dams in its upstream. Moreover, the thinning down of Himalayan glaciers means that rainfall in Sindh is extremely erratic; so the Manchar does not receive much water from the torrents either. Environmentalists Naseer Memon and Zubaida Birwani note that, "The mean annual rainfall in Dadu is 4.43 inches (112.5 millimetres) while annual evaporation is about 80 inches (2,000 millimetres). Therefore, very little runoff is generated in catchments of hill torrents. The lake gets recharged only when there is heavy rainfall, which usually happens once in three years."
A community vanishes This has meant that Manchar can provide scarce support to communities who have lived by it for centuries -- perhaps even ages. Amongst them are fisherfolk called the Mohanas. Architect and town planner Arif Hasan -- who also writes on environmental issues -- says, "Folklore has it that the Mohanas are descendants of people of the Indus Valley Civilisation. Some suggest that the word Mohenjodaro is a corruption of Mohana-jo-daro -- the tomb of Mohanas." They are a fast dwindling community today. According to Ghulam Mustafa Mirani, vice-chairperson, Pakistan Fisherfolk Forum, "There were once 60,000 Mohanas at the lake. Their population has dropped to 25,000 today because of droughts over the last five year and increasing effluents in the lake." (See graph: Rising poison)

The community's source of livelihood has suffered a lot. As per a report of the Sustainable Development Policy Institute (sdpi) -- an independent think-tank based in Islamabad --the fish catch in the Manchar has fallen from 3,000 tonnes to less than 100 tonnes in 2003. "Before 1999, I could catch about 20-25 kilogrammes (kg) of fish every day. Today, it has come down to 5-6 kg," laments Analdal, a member of the Mohana community. Rues another Mohana, Haji Karim, "We used to eat fish and roots of aquatic plants. It was like a free meal. We only brought wheat and rice. Manchar was like a cup; it has now turned into an empty saucer."

The effluent-ridden lake water is no longer fit for drinking. So, the Mohanas have to purchase drinking water from a supply facility at the embankment. Each bucketful costs 5 Pakistani Rs. And there is crisis when water cannot be pumped out during power breakdowns.

The sinking lake has also put paid to the livelihoods of hundreds of agriculturists who diverted its waters through small canals, phats, and then used the lake-bed for farming. According to Memon, "This method relied on filling the lake during monsoons and then drawing out water to uncover cultivable land on which wheat was grown." He notes that, "The lake was filled to about 113 feet by September end and was reduced to 106 feet in October. In the process, about 26,000 acres of land was uncovered for farming." But today, Manchar doesn't have enough water and the lake-bed farmers have no work.

And that is not the end of their woes: the lake's toxic waters have played havoc on the health of their livestock. According to Behram Chachar, team leader veterinary project, Indus Resource Centre (a non-governmental organisation that promotes informal education in Sindh), "Viral diseases, such as rinder pest and foot and mouth, and bacterial diseases such as haemorrhage septicemia and black quarter have become common among livestock. The animals in the area are also plagued by tympina/bloat and acidosis."

An unwelcoming place
The lake's once-rich marine and aquatic life has also suffered. Mirani lists about 10 fish species that can still be found in Manchar but says that their diversity and numbers were much higher, even a few years back. In the past, the lake waters were kept at 112-reduced level (rl, the lake's water height with respect to mean sea-level). The surplus was diverted to the Indus; "fish seeds" swam into the lake against the flow of the Indus-bound waters. The process was a boon for the Mohanas, for these little creatures would grow up to weigh a tasty 2.5 kilogrammes. That's a thing of the past now. For, even with good rains last year Manchar's water level reached only 108.2 rl.

I
n the past, the lake was the winter home to numerous migratory birds species. Since it was the first wetland on their route, Manchar during winters was redolent with a host of migratory bird species. In fact, according to the environmentalist Shujaudin Qureshi, "About 20,000-30,000 birds still visit the lake every year." However, Qureshi also adds that pollution has caused a drastic fall in their numbers. Mirani also notes that migratory birds do visit the lake, but fly off after an overnight stay.

It is clear: Manchar is dying and its water can now kill.

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