KARACHI, May 26: Several factors are implicated in the current water pollution crisis in Hyderabad and some other areas. The widespread use of synthetic agricultural inputs - chemical fertilizers , pesticides etc - means that the soil is infested with various forms of chemicals.

Agricultural run-offs laced with deadly chemicals, comprising even heavy metals, are released into water bodies and eventually all these end up in the Indus, which after passing through Sindh empties itself into the Arabian Sea.

A large number of industrial units have also been established along the banks of the rivers or canals or other water bodies. Since due to rampant corruption and also non-technical people in the monitoring agencies, environmental laws, which prescribe that industrial effluents should be treated before being released, are not implemented, untreated hazardous industrial effluents also enter the canals and eventually into the Indus. The Indus water entering Sindh is thus already heavily polluted with deadly contaminants.

Sometime back, the government initiated two huge drainage projects - the Left Bank Outfall Drain (LBOD) and the Right Bank Outfall Drain (RBOD) - to take out saline water from the water- logged areas of upper Sindh, adjoining areas in Balochistan and Southern Punjab.

The government designed the RBOD in such a way that it emptied its infested water into Manchhar Lake. This lake receives rain water in its catchment area and also water from the overflowing of the Indus during the monsoon.

Thousands of fishermen live and spend their whole lives with their families on boats. A large number of migratory birds also used to go there from the colder Central Asian regions to spend the winter.

When the government announced and started work on laying of the RBOD towards Manchhar, environmentalists raised a hue and cry that it would destroy the fresh water eco-system and harm the livelihood of the fisher folk.

The government paid no heed to this and completed the project and started to empty the deadly load of the RBOD into Manchhar Lake and in no time the entire sweet water eco-system was disturbed, fresh-water fish species vanished, migratory birds began avoiding the lake, and eventually a majority of the fishing community having no fish to catch or even birds to eat, migrated.

Now to save the lake bureaucrats are trying to take the hazardous drain water to the Arabian Sea through the Indus. As if the contamination in the Indus water carrying this pollution load - untreated industrial effluents and agricultural run-offs, etc - from upcountry was not enough, the introduction of the contaminated Manchhar water is making matters worse and leading to incidents such as those reported from Hyderabad.

The quantity of water in the Indus has considerably gone down and is meagre during the dry season. During the monsoon, when the river has more water, pollutants become diluted.

All the towns and cities that are getting their drinking water from the Indus are getting contaminated water, but as a majority of these towns are small and people are not aware of the dangers, we hear little from these places.

But as Hyderabad is the second largest city of the province and people are more aware and medical facilities are comparatively far advanced, this issue has been identified in the media.

If the government carried out a comprehensive study of the impact of the contaminated water on the people residing in the towns and cities which are getting their supplies from the Indus, more revelations will surely surface.