It was once a river where strong currents flowed giving it life and vibrancy. Over the last few years, however, the Shitalalkya River is now on the verge of an untimely death. Environmental degradation in the river water from untreated domestic and industrial effluent has reached such an alarming level that it poses a significant threat to public health, ecosystem and economic growth of surrounding areas. The water is so polluted that no aquatic life can survive during the six-month dry season, which has drastically changed the socio-economic structure of the localities adjacent to the river. Residents nearby have no choice but to do their washing in the pitch-black malodorous water. Moreover, a huge number of Dhaka city dwellers are directly affected by water pollution of Shitalakkhya River, since Water Supply and Sewerage Authority (Wasa) supplies water for the Dhaka residents treating such contaminated water at the Saidabad Water Treatment Plant.
Everyday, Wasa supplies 22.5 crore litres of water to Dhaka households and plans to supply altogether 90 crore litres in the future. All this water comes from the Shitalakkhya and is treated at the Saidabad Water Treatment Plant. Wasa is also planning to set another water treatment plant, which will also use water from Shitalakkhya and its tributary Balu River.
Strategically Shitalakkhya is the most important river for Dhaka dwellers in terms of its use in domestic life. The adjacent areas of Shitalakkhya River has been termed by Dhaka Metropolitan Development Plan (DMDP) (from 1995 to 2015) as an 'environmental pollution protected zone'. The Shitalakkhya has been considered as relatively unpolluted compared to other water bodies and hence targeted being potentially a major source of drinking water for the ever-expanding population of the city. The DMDP has also suggested initiating environmental protection measures to prevent pollution of the Shitalakkhya River and its tributary, the Balu River, in order to ensure that it remains a viable, long-term source of potable water of Dhaka City.
According to the Plan; Rajdhani Unnyanan Kartripakkhya (Rajuk), Bangladesh Water Development Board (BWDB) and Department of Environment are the implementing agencies to control all industrial and commercial development, existing and future, within one kilometre of the rivers. Furthermore, these agencies are supposed to make sure that minimum standards of effluent control are maintained by constantly monitoring the surface water of the rivers. They are also supposed to identify and stop any kind of pollution in the water.
The real picture, however is a far cry from the Plan's noble intentions. Ignoring the government plan as well as laws such as Environmental Conservation Act (1995) and Environmental Conservation Rule (1997) the river water is being degraded by the effluent flowing in from two directions: the outflow of sewage from the centre of Dhaka, and from the clusters of industries and urban development located along the outer edge of the watershed. The result is a thick layer of pitch black coloured effluent in the water throughout the dry season. The water flow decreases from 2742 cubic metre per second (cumec) to 173 cumec for six months of the year (December to May) but the volume of effluents discharged in the river remains nearly constant. A common complaint is the foul-smelling water supplied from Saidabad Water Treatment Plant. Moreover, there is every possibility of toxic heavy metals being pumped into Wasa supply line which may cause serious health hazards. Nutritionists believe that people all over the country may face health risk through the consumption of contaminated products of the Shitalakkhya River such as fish and vegetables grown in the surrounding areas.
The risk to health has been clearly stated by a World Bank report on environmental and water resource of greater Dhaka. Published in March 2008 the report states that community members reported to having contracted stomach diseases. Communities that are more directly dependent on natural resources have also been sufferers. The report also mentions that 63 percent of farming households reported a gradual decline in Boro rice production for the ongoing pollution at the periphery areas of Dhaka. The report also states that there appears to be no fishing activity whatsoever in the dry season in the rivers and canals in greater Dhaka.
In fact, this lively river has become biologically dead making it dangerous for human and livestock use. Clearly, the people and the economy are paying a high price for the degraded environment in the catchments of the river. Once, the Shitalakkhya was a rich source of several indigenous species of fish such as ritha, bowal and chital, now there is no fishing at all during the dry season in river water. Even during the wet season, fishing is not possible on commercial basis in the river, informs sources at the Department of Fisheries. Which is why fishermen are switching to other professions. Those who are still hanging on to family tradition, continue to suffer.
"During the dry season we have to take our boats seven miles downstream. We collect snails from the Dhaleswari River near Munshiganj, since we don't get any fish or other aquatic animals in Shitalakkhya. We sell these snails to the poultry farmers", says Nironjon Das, an ageing fisherman of Rushki, a village on the bank of river Shitalakkhya in Rupganj, Narayanganj.
Professor M Mujibur Rahman | River pollution has adverse impact on fisheries. |
"Even in the wet season we get only a few puti fish from the river now, but a variety of fish like foli, chital, bailla, ritha and bowal were available in the Shitalakkhya before", he adds.
A recent incident shows just how badly fish and other aquatic life have been affected. A few days ago, the Water Development Board had supplied water from the Shitalakkhya through DND canal for irrigation at Shimlail area near Narayanganj, where there are many fisheries. "Just within an hour all the fish died in the firms those used such contaminated water", informs a high official of Bangladesh Water Development Board on condition of anonymity.
Explaining the reason behind this fisheries experts, hydrologists and environmental experts say that the dumped effluents from domestic and industrial sources in the river water deplete the oxygen level in the water to a point where no creature can survive.
Corrosive elements in the water have led to skin diseases in people for whom the river is the only place where they can wash and bathe. The World Bank report states that skin disease, jaundice, diarrhoea and dysentery are correlated to water pollution. Residents of the area complain that they cannot use the polluted river water for household chores either.
"The pitch black malodorous water gives itching skin and rashes," says Ambia Begum, a resident of Rushki, who has to bathe in the river, as there is no alternative water source for her and many others in the area.
Addressing the ongoing environmental degradation in the catchments of Shitalakkhya River and its tributary Balu River the World Bank blames growth of industries, which use inappropriate technology and processes as well as unplanned urbanisation. The other important factors are institutional failures, lack of enforcement, policies, which provide disincentives for environmental conservation, and governance constraints. The report also mentions that being pressurised by the development partners, the government has promulgated a few laws and has formed the Department of Environment. But these initiatives are not adequate to control ongoing environmental degradation.
Many edible oil mills discharge untreated effluentes in the river water. |
The report reads, "Board of Investment in Bangladesh does not ask the investors to provide any information on the potential environmental impact of proposed manufacturing activities. Rajdhani Unnayan Kartripakkha (Rajuk) is only implementing the laws in the Dhaka Strategic Plan, which allows dispersed industrial growth. This approach is making it difficult to manage pollution and also has encouraged encroachment on wetlands. Rajuk's view is that the Department of Environment should look after the environmental impacts. On the other hand Department of Environment as the largely ineffective regulatory agency. The structure, knowledge base and approach to environmental management in DoE are dated and inadequate to deal with the problem. Dhaka City Corporation (DCC) and other pourasavas are responsible for poor and inadequate solid waste collection and disposal. Dhaka Wasa, moreover, has not succeeded in performing its basic functions of providing adequate sewage and storm drainage systems. Additionally, they have no policy on how toxic sludge should be removed and disposed."
Institute of Water Modelling (IWM), has done the technical study of the World Bank report. IWM is a trust established by the Government of Bangladesh in December 1996 to function as a centre of excellence and learning in the field of Computational Hydraulics, Water Modeling and Allied Science. It identifies industrial clusters in Gazipur, Tongi, Tejgaon, Tarabo, Ghorashal and Narayanganj and hundreds of units operating outside these clusters for the ongoing environmental pollution in Dhaka watershed including the 73 kilometres long Shitalakkhya River that flows from the Old Brahmaputra at Pakundia Kishoreganj and falls in Dhaleswari River near Munshiganj.
These industrial clusters and individual units are far from being homogenous. They include chemical processing units, textile units, plastic units, dyeing units, steel rolling, fertilizer units and oil units. An estimated 35 textiles, seven oil mills, five paper mills, two fertilizer mills, two washing plants and others are marked as the major pollutants of the river.
"Except the upstream part (above the confluence of Balu-Lakhya Rivers at Demra), the rest of the river systems is extremely polluted and cannot be thought of for any beneficial use", says SM Mahbubur Rahman, principal specialist and Head of Water Resource Planning Division of IWM.
"A very deep colour of the river water, very high Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD)indicate major pollution in the river water that depletes dissolved oxygen. A very low level of dissolved oxygen (DO) threatens aquatic life. Almost all of the industrial clusters of individual units discharge toxic chemicals such as chloride, sulfate and others. Toxic heavy metals have also been detected in the effluents from some industries", he adds.
Many factors that vary from location to location must be considered to address the degraded state of water resources. According to Mahbubur Rahman, the Environmental Quality Standards (EQS) for the rivers in Dhaka Watershed needs to be more stringent to ensure desired water quality in the rivers. For instance, he says, the water quality model results indicates that the BOD of discharged effluent should be less than 30 mg/l in Shitalakhya in place of 50 mg/l, as per EQS, to ensure DO level higher than the desired 5 mg/l in river water.
"As per IWM recommendation the World Bank is interested to set Common Effluent Treatment Plant (CETP) at various points to control the ongoing water pollution in Shitalakkhya River. Initially three CEPTs will be installed at Tongi Ghorashal and Tarabo. The rest of the recommended CETPs will be installed in Narayanganj and other industrial clusters. After installing these CETPs the scenario will be improved", he adds.
Domestic and industrial effluents are carried to Shitalakkhya River through Narai canal. |
At the same time Rahman says that there needs to be greater awareness about this kind of environmental pollution and greater pressure on industries to adopt 'cleaner production technology' as well. "Cleaner production is one of the several innovative approaches to long term reduction in environmental pollution in Bangladesh, and particularly in the Dhaka watershed. 'Cleaner production technology' will decrease production cost as well as reduce the load of pollutants significantly in industrial discharge, which will make common effluent treatment infrastructure feasible to run”, he says.
But saving Shitalakkhya River is not possible unless pollution of its tributary Balu River and other canals, is controlled since both domestic and industrial wastes through these water bodies fall into the river. Industrial pollutants from the Tejgaon cluster, located at the centre of Dhaka City as well as domestic wastes of the eastern part of Dhaka City are carried to the Balu River through several canals. Most of these canals meet at Trimohini point in Demra. The ongoing pollution in the catchments of Balu River has reached such a level that the river and the canals of the area have become a threat to the people.
"It's really difficult to survive next to Balu River. We haven't been using water from the river for the last 12 years. Moreover, it has become a breeding ground for a huge quantity of mosquitoes during the dry seaon. The stinky river has become a curse for us," said M Jahangir Alam, a local resident of Rajakhali, a village on the bank of Balu Rive at Demra, about a kilometre upstream from the confluence of Balu-Lakhya Rivers.
Professor M Mujibur Rahman, a teacher of Civil Engineering Division of Bangladesh University of Engineering and Technology under whose guidance the ongoing Begunbari-Hatirjhil Beautification Project is going on, is highly critical about Dhaka Wasa for not being able to provide a proper sewage system for Dhaka dwellers. According to Professor Mujib the organic pollution in the river is contributed by the poor state of sewerage and sanitation system of Dhaka's urban areas. "Presently, the underground sewer network covers only 30 percent of the existing urban areas of the city, and 20 percent of the population residing in it", continues Professor Mujib, "For the remaining areas especially the fringe areas which are witnessing rapid development recently and comprise mostly of low income neighbourhoods, mostly drain the domestic sewage into the canals which are ultimately discharged in the Shitalakkhya River through Balu River."
Locals bathe in the river, as there is no alternative water source for them.
"During the dry season Balu River and other canals connected to Shitalakkhya River carry only waste water. Both industrial effluent and untreated domestic sewage discharge are equally responsible for the degraded state of water resources. Besides, there are so many hanging latrines on Balu River and other canals. So the problem is very complex", says Professor Mujib.
"Wasa must address the problem to the government so that it can provide proper sewage system in Dhaka to save its water bodies. Until it reaches the target of assuring proper sewage system it should force the Dhaka dwellers to use alternative sanitation facilities like septic tanks and soak pits. The government should also take steps for sanitation facilities in the slums where hanging latrines on the canals is common", he adds.
Professor Mujib suggests installing five or six Sewage Treatment Plant (STP) at several points in Dhaka so that the domestic wastes do not drain in the river water. He says, "World Bank is going to install a CETP-STP combined facility at Dasher Kandi point at Demra where three major canals meet in one point and discharge wastes in Balu River. After installing the treatment plant water of both the river Balu and Shitalakkhya will be improved."
Professor Rahman also suggests dredging Balu River to increase its flow, which is only 60 cubic metres per second during the dry season. According to him flow of the river must be increased to get proper benefit from the treatment plant. "At the same time the disposal of ongoing industrial waste in river water must be controlled at any cost. I don't understand the role that the Department of Environment is playing. Under the current scenario no new industrial unit should be allowed to install within one kilometre of both of the rivers Balu and Shitalakkhya", he says.
Dhaka Wasa is preparing, with funding from the World Bank, its sewage master plan,
A CETP-STP combined facility is going to be installed at Dasher Kandi point to save Shitalakkhya River from the effluents discharged from the centre of Dhaka City. |
which is expected to begin functioning from 2012. If the programme works properly, it will help to control domestic waste disposal in river water. But the problem is that no organisation is concerned about the disposal of industrial and domestic wastes into Shitalakkhya River from the DND area. The DND area, under Water Development Board, was developed for agricultural activities. But, at present the highly populated area has turned into a semi-industrial zone. And both domestic and industrial wastes are disposed in Shitalakkhya River through the DND canal.
In fact, ongoing pollution of Shitalalkhya River and its tributary Balu River must be controlled at any cost for the sake of public health, ecosystem and economical development of the surrounding areas. This requires support for the enforcement agency, in order to strengthen its regulatory capacity, its capability to work with industry to introduce pollution prevention and waste minimisation approaches. It is also necessary to ensure co-ordination between the concerned ministries and agencies. Moreover, industry should be provided with a package of incentives and technical assistance to encourage them to adopt sustained use of waste treatment and waste minimisation technologies. At the same time it must be ensured that different agencies such as Wasa, Dhaka City Corporation, Rajuk, Bangladesh Water Development Board and Pourashavas play active roles to control pollution of Shitalakkhya River and its tributary Balu River and other water bodies.
Unless the concerned bodies make a united effort to arrest the terrible degradation of this crucial river, the Shitalakhkya will face the same fate as many of its sisters: a slow and painful death.
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