Water: Life and death
To us, water is the most precious substance, the substance from which all life upon the earth has sprung and continues to depend. If we have no clean, drinkable water, we are doomed. This is exactly what has happened in the country of late. With flood water inundating almost one third of the country affecting the lives of about 20 million people and surface water getting seriously contaminated by sewage flow from open outlets, the country now faces an environmental disaster that threatens public health in the flood affected areas. As flood water recedes from different parts of the country, the incidence of diarrhoea and even cholera has shot up to an astounding number. With about one thousand patients getting admitted to the Icddrb hospital at Dhaka almost on a daily basis, the issue of drinking water pollution has featured most prominently.
While explaining the cause of such huge number of cases, doctors at the Icddrb hospital pointed their fingers at the WASA water supplies being contaminated severely which the WASA authorities have consistently denied. Undeniably true, earlier studies indicated that the country's rivers were among the most polluted and contained ten times as many bacteria from human waste as waterways in any other country. Now with the sewage flow from open outlets containing human excreta compounding the water pollution crisis, the lives and livelihoods of millions are at risk and the nightmare has only just begun.
In the backdrop of the crisis now mounting up with abundance of water because of the flood, Dhaka and its periphery on the other hand routinely lives through water cuts from January to June every year. Rural Bangladesh, yet to be acquainted with the tap water culture is worse off as ground water levels have plunged in most of the districts.
Like so many of the earth's bounty, water is unevenly distributed. Water covers 75 percent of the Earth's surface -- 97.5 percent of that is salty and only 2.5 percent is fresh water. Icecaps and glaciers hold 74 percent of the world's freshwater, almost all the rest is in deep groundwater aquifers, or locked in soils as moisture or permafrost. Only 0.3 percent of the world's freshwater is found in rivers and lakes. Less than 1 percent of the world's surface or below- ground freshwater is accessible for human use. At the dawn of the new millennium, more than one billion people do not have access to safe drinking water, and 3.4 million die each year from water related diseases.
Within the next 20 years, half the world's population could have trouble finding enough fresh water for drinking and irrigation. Currently over 80 countries, representing 40 percent of the world's people are subject to serious water shortages. Conditions may get worse as in the next few years as populations grow and as global warming disrupts rainfall patterns. Part of Asia faces the greatest threat. Over 90 percent of the region's population is experiencing severe water stress, with water consumption exceeding 10 percent of renewable freshwater resources. In Bangladesh and adjoining areas, people living without access to adequate water and sanitation are the poorest and most vulnerable. The problem is particularly severe in remote rural areas and rapidly growing urban areas. As much as 90 percent of waste water in developing countries like ours is discharged into rivers and streams. Water-borne diseases are responsible for 80 percent of illnesses and deaths in the developing world, killing a child every eight second.
It is comforting to learn that per capita residential use in Europe runs as high as about 200 litres. This is not surprising in view of the fact that European commission made water protection and sustainable management one of the priorities of its environmental and research goals. In contrast, Bangladesh situation, especially the situation in big cities like Dhaka, Narayanganj, Chittagong, Khulna and Rajshahi in respect of water hazard and contamination is appalling. Factories in these big cities and also the city dwellers happily discharge harmful chemicals and toxic wastes into rivers while growing need for food induces farmers to use agrochemicals, insecticides and pesticides that further pollute the river water. Mentionably, ground water is the main source of supply through Deep Tube Well (DTW) either in the cities or for irrigation in rural areas. But the yearly recharge of the aquifer is less than the abstraction. Growing dependence on ground water for these needs is lowering the water table, making arsenic contamination the most pervasive health hazard the country has been experiencing now.
Rivers in developed countries because of increased awareness and education of the citizenry have become much cleaner over the last two decades. On the other hand rivers in the poorest developing countries, by contrast have shown marked falls in levels of dissolved oxygen¾a key indicator of increased pollution by sewage.
The first signs of population boom and water stress were visible in the 1980s, but the water management board at that time focused on the immediate -- tapping groundwater resources in the whole country. Expectedly, the pressure on ground water has shown up. And as basins and rivers dry up, it also threatens the country's food security, because most of our freshwater is used to grow food. While the daily drinking water needs of every person is approximately four litres, between 2000 and 5000 litres of water are needed to produce an individual's food requirements. More importantly, agriculture accounts for over 80 percent of world water consumption. It is estimated that between 14 and 17 percent more water will be needed for irrigation by 2030 to feed the world's growing population.
With the level of groundwater dropping at an annual rate of nearly 15 feet as WASA sources say, supply of water would be extremely scarce within a few years. Experts argue that over-extraction, lack of retention points for recharging groundwater, pollution in the waterways adjacent to the cities and towns, and a natural impermeable clay layer have combined to further push the level down to an unreachable depth of the earth's crust. Water is being mined and pumps are being sunk three to six feet deeper every year.
Dhaka WASA supplies roughly 120 crore litres from its deep tube-wells against its daily requirement of 160 litres while its surface water treatment plants at Lalbagh and Godnail provides less than five crore litres. It is now trying to strike a balance between surface and underground water at least in the city. But that idea seems to be building castles in the air because Dhaka city is increasingly becoming “built up” with rapid depletion of open spaces, wetlands, canals and rivers and an annual growth of about eight lakh people leaving no space for the ground water to be recharged. With about 97 percent of the city's water supply coming from underground source, there is an imperative need to use surface water to have that balance. Because once a break is applied to extraction, groundwater would automatically get recharged. But how can that be achieved?
With water of the Buriganga and the Shitalakhya being polluted at an alarming rate, experts are not sure if it could be treated at any of the plants. The Hon'ble Adviser in charge of the Ministry of LGED has been telling in meetings and seminars that efforts are underway to bring water from the river Jamuna to meet Dhaka city's water gap. Sensible citizenry feel that the cash starved Dhaka WASA can ill-afford the cost of such an endeavour. Shockingly, conservation has not figured in the government's scheme of things either during the past regime or even now when the government is run by a band of dedicated people with no political motive or agenda.
Leaving aside the Buriganga and the Shitalakhya that now symbolise little life, water in the Gulshan-Baridhara and Uttara lakes is now a receptacle of human wastes, raw sewage and toxic industrial effluents from various industrial units. According to a study conducted by the DoE in the recent past, these lakes' water carries a bacteria count of 1200 in place 200 or less that is considered to be a tolerable count in water bodies. Uttara Lake, once a vast transparent water body stretching from one end of sector no.3 to sector no.11 at least 5 km. in length and 400 m wide is now a stagnant pool of polluted water because of indiscriminate dumping of household garbage, wastes and raw sewage from the bustling residential buildings all around. Its width and length have shrunk with construction going apace and people coming in to settle.
Known to be the barometer of the ecological health of a city, water bodies, other than being sources of surface water, 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.
The process of cleaning and recharging may undoubtedly be a long drawn one. The first step is to identify the sources and entry points of sewage discharge into the lakes and waterbodies and divert it to suitable place for safe disposal. It is worth mentioning here that under Indian government's National lake conservation project, the LDA (Lake Development Authority) has cleaned up in just about a year12 odd lakes. One of Bangalore's biggest lakes -- the 50 hectare Ulsoor -- was drained out and sewage lines were blocked. With funds from the donor agencies other than the government itself, Bangalore Water Supply and Sewerage Board started laying pipes leading to the treatment plant. Now catch-water drains have to be built to collect water run-off. That done, water has to be purified using hydrophyllic plants that absorb dissolved pollutants and toxins.
What happened in Bangalore was that in 1995 a sudden rise in the death of freshwater fish in lakes like Sankey and Lalbagh sounded an alarm and the government then took comprehensive plan for restoration of such lakes. Unhappily in our country mass death of fish in the Baridhara-Gulshan lake in 2002 and also in recent time could not sensitise much the administration that other than being an aesthetic and ecological utility the lakes could be a vast source of poor man's protein.
Like the one that our neighbouring country had taken up, the present caretaker government that has brought about many reforms in different sectors, may now be considering the modalities of raising external and internal funds on the lines of the World Bank aided programme for integrated countrywide tank and lake development for irrigation, ecological balance and aesthetic quality of the cities and countryside. Such development work can fruitfully be done when governmental efforts combine with individual civic initiatives.
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