Surface Water Consevation and Mitigation of Water Crisis

With most countries in Africa and Asia facing humanitarian crisis with the inadequate water and sanitation provision that has led to wide spread attack of cholera, diarrhea and other intestinal diseases resulting in high fatalities, the observance of World Water Day every year on March 22 has become a solemn farce.

Precisely speaking, water -- which scientists tell us finds its own level -- also happens to be the great leveller. It is fundamental to our very survival. But every summer Bangladesh in the past few years discovered that life with water shortages is increasingly becoming constrained. From being a necessity water has now become a luxury. With pipes running empty, residents especially in Dhaka and Chittagong are looking for alternative sources like tankers serviced by Wasa in extreme crisis situation.

As for the villages, the situation is far more pathetic. With shortages of water due to drying up of ponds and with no visible effort of digging fresh ponds during the last several decades other than what the affluent land lords in the villages did in their hey days, farmers year after year remain mired in their old practice of sinking tube wells deeper and deeper to reach the decreasing level of ground water.

Water, it seems is the single big crisis facing Bangladesh now exacerbated by the construction of Farakka barrage over the river Ganga in the Indian territory. Undeniably true, urban Bangladesh is screaming for water and with water table going down and down, the situation is set to deteriorate further. The demand for fresh water in Dhaka city comes to about 2100 million litre. Dhaka Wasa provides about 1800 million litre through 550 deep tube wells and four water treatment plants in different locations of the city.

Pathetically true, with no visible effort to conserve surface water, about 85 per cent of the supply requirement has to be met from underground. The first signs of population boom and water stress were most visible in the 1980s but most municipalities and city corporations focused on the immediate -- tapping ground water resources in and around the cities. Expectedly the pressure on ground water has shown up. In a word, water is being mined and pumps are being sunk 10 to 20 metres deeper every year. Desperate dwellers, not only in cities but even in villages are forced to buy water from vans ferrying it in water starved areas.

Worse, conservation has not figured in our scheme of things -- neither directly through steps like water harvesting nor indirectly through restoration of canals, lakes and water shades, that have been encroached upon by land grabbers.

It is difficult to think of Baridhara, Gulshan, Dhanmondi, Uttara, Badda, Rampura areas in Dhaka as being anything other than what it is today : a veritable jungle of residential apartment blocks teeming with schools, clinics, shopping malls and private universities. There were once lakes and canals within and running through the city zones like Segunbagicha, Purana Paltan, Narinda, Gandaria, Rampura and Bashabo.

To put a count to it, about 250 sq. km of watersheds around the city surrounded by the rivers Buriganga and Shitalakhya have either been encroached upon or dried up due to inadequate flow in the main water bodies. Other than anything that is not noticeable, the result has been a drastic depletion in the water table, evidenced by the fact that bore wells in the city have to go deeper and deeper.

The immediate task of the utility organizations like Wasa, Rajuk and Dhaka City Corporation would be to carry out efforts to boost water table in Dhaka city and its adjoining areas. But our experiences suggest that all these organizations, because of lack of coordination cannot do it and each one of them is trying to pass the buck on the other. There should be an autonomous body for the protection, conservation, restoration, regeneration and integrated development of the lakes, watersheds, and rivers like the Buriganga, Shitalakhya, Turag and Balu and many other lost canals.

To cite an example, in the Indian city of Bangalore, such an authority constituted under the department of Environment, has been working to halt encroachment on water bodies by land grabbers. Bangalore woke up to the loss of its wetlands and got down to restoring the city's 600 odd lakes.

Our immediate task would be to identify such water bodies as well as to recover those already filled up illegally for recharging by draining out the poisonous soup and blocking the sewage lines connecting them. Such authorities should be invested with fund, responsibility and authority to clean up all such lakes in Gulshan, Banani, Baridhara, Uttara and Dhanmondi.

Needless to mention, Dhaka Wasa has to find out ways and means to lay sewage pipes and link it to treatment plants that it must construct to save the city dwellers from the growing load of pollution and sewage that will increase at least five times the present output by the year 2020 when the population will jump to 300 million as some demographic data by the World Bank sources suggest.

And that's the reason the World Bank experts have warned that unless measures are taken well ahead Dhaka will turn into a dead city by the year 2020.

Known to be the barometer of the ecological health of a city, water bodies also determine its climate. As experts explain, they help control humidity and temperature levels, recharge aquifers and also act as instruments of rainwater harvesting. With a little initiative, commitment and imagination these lakes could be formed into a hydrological chain and during monsoon, surplus water from the upstream lake could be flowed into the next lake. Sadly true, rapid urbanization has led to the loss of wetlands. The biggest problem has been encroachment on and disposal of untreated sewage into the lakes anywhere and everywhere. Studies have revealed that these lakes and water bodies have become full fledged sinks for domestic sewages, effluents from industries and agricultural run off of silt and pesticides that are wrecking havoc on the ecosystem.

The process of cleaning and recharging may undoubtedly be a long drawn one. But with political will and commitment it can be done. It is worth mentioning here that under Indian government's national Lake Conservation Project, the LDA (Lake Development Authority) has cleaned up in just one year 12 odd lakes. One of Bangalore's biggest lakes - - the 50 hectare Ulsoor -- has been drained out and sewage lines have been blocked. With funds from the donor agencies other than the government itself, Bangalore water supply and sewerage board undertook the construction of pipes leading to the treatment plants. Catch water drains have been built to collect water run off. That done, the process of purifying water by using hydrophyllic plants that absorb dissolved pollutants and toxins to be undertaken.

Programmes like the ones that our neighbouring countries have taken up, the government here should now be considering to undertake with the modalities of raising external and internal funds on the lines of the World Bank aided project for integrated countrywide tank development for irrigation. Such development work can fruitfully be done when government effort combines with private initiatives. In city, with indifference, negligence and inaction galore, for instance, Uttara lake, a vast water body almost 3km in length and 300m wide, is destined to turn into a giant sewer. Raw sewage combined with toxins, effluents and garbage are being discharged into the lake indiscriminately without anybody thinking of noticing the dire consequences that pose as a serious threat to the residents, especially the children living in houses close to the lake. All such lakes, other than being an aesthetic and ecological utility, could be a source of Wasa supply water source in times of severe water crisis in city areas.

Paradoxically, on the occasion of the observance of the World Water Day, people in the country felt vastly amused when they heard some high-ups in the administration speaking glibly in seminars and rallies about conserving the surface water to reduce too much strain on ground water that is getting exhausted fast. Precisely known to all, surface water helps aquifers being recharged. But the looming question is: where are these sources to be found if we are wilfully destroying and contaminating them ?

Writer

Md. Asadullah Khan

Department of Physics

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