Water is life, but that often turns into a curse for the city dwellers in Dhaka. Being the capital of a riverine country Dhaka is blessed with rivers around it and actually the city was being built and became a pramount due to these rivers. Ironically, these rivers have not only lost their glory but also becoming a heavy liability upon the city.
The source of most refreshing potable water has become dirty sewage container. Moreover the heavy deposition of waste has made it a total mess.
110 square Kilometre area of the Shitalakkha, the turag, the Balu and the Dhaleshwari, the surrounding rivers of Dhaka is being polluted by the contamination of tannery situated in Hazaribag. A decade earlier, Government took initiative to relocate tanneries and apporved a ‘tannery town’ in Hemayetpur of Savar at a meeting of executive committee of economic council on 16th August 2003. It was supposed to finish within 2005 but the time was extended for five more years and then another two more upto 2012. Despite extension of the schedule thrice, the work is yet to be finished.According to the Department of the Environment (DoE), 20,000 tonnes of tannery waste, including some highly toxic materials, are released into the river every day
Apart from tannery there are many more big and small industriues in the bank of these rivers. Most of them do not have proper ETP( effluent treatment plant) and they do not follow even the basic laws regarding the protection of rivers. Experts identified nine industrial areas in and around the capital city as the primary sources of river pollution: Tongi, Tejgaon, Hazaribagh, Tarabo, Narayanganj, Savar, Gazipur, Dhaka Export Processing Zone and Ghorashal. Most of the industrial units of these areas have no sewage treatment or Effluent Treatment Plant (ETP) plants of their own. Although with the water act 2013, River protection act 2013, The environment conservation rules 1997 have provision of punishment to them, but they evade by corruption, political muscles and lackluster role of River commission and other authorities. Back in 2009 High court directed the government to demarcate river banks, but that is not yet implemented. That is related to another huge problem, namely, the encroachment of river. The problem is severe for these rivers and the pollution is optimum for encroachment.
One of the most crucial issue is the sewage management of the city, A city of 344 square kilometres with more than 15 million inhabitant the function is humongous, amazingly there is no proprer sewarage management system.
In capital, everyday 9000 tons of waste is produced, 49 percent of them are from household and rest from commercial, industrial and hospitals. Only about 5-6% of the waste is recycled despite the presence of tenchnology and manpower.Hasin Jahan, Program Director of Wateraid, Bangladesh said, less than one-fourth of Dhaka city area is currently under the coverage of sewerage network. In Dhaka, where there is no sewerage network, more than half of the buildings are not having any septic tank and the sewer pipelines of these buildings are directly connected either to the open drain or to the storm drainage system polluting the surface water and the environment.
Apart from that, the solid waste produced here daily, that disposed directly to the rivers without treatment. A recent Asian Development Bank (ADB) research published that, by 2015, this city dwellers will generate 8000 tons solid waste, which need 292 hector land for management, which is not possible.
If we think about recycling the waste, then it would be a possible way for management, said Hasin Jahan. Bangladesh uses around 3.5 million tons of fertilizer every year of which about 2.6 million tons are imported. Government provides subsidy of around 18 taka/kg of fertilizers to the farmers. Hypothetically, if we could convert the entire amount of sludge produced in the country into proper fertilizer that will turn upto 3 million tons. Bangladesh can save an estimated amount of 5,000 crore Taka/year. Even if we could utilize a certain percentage of this potential, it could be a huge gain for the country. This should not be considered from monetary perspective only; use of this manure will improve soil texture and environment. It will save the treatment cost for turning polluted water into drinking water standard at water treatment plants by not polluting surface water. However, this could be thought as one of the propositions towards managing sludge.
At the same time, Environment specialistEngineer Nasir Uddin Khan, based on UK, stated about the present scenario of water pollution due to the sewage waste at Dhaka city. He said, if any kind of action would be taken for human waste management then the rivers would get back their life. In the early time, river water or any other source of surface water are used for drinking and cooking purpose. But, nowadays, the odor of the Buriganga river water makes a feeling of waste dumping zone rather than a river. It cannot be clear by imposing penalty on industries situated on the bank of rivers. It is not the permanent solution. Those industries have the ETP, but they don’t use that all the time. If they are bound to construct CETP, then individuals cannot take decision of not using ETP. And, by that way, industrial waste water can be treated. At the same time, the waste collection process would develop, and then the generated human waste can be recycled to energy. He also blamed to RAJUK for developing an unplanned sewage system in this city. If authorities can take action to separate the solid waste by improving the design of the sewage line, the rivers turn back to alive. That the way, surface water condition would be improved for use.
All knows that, water supply of Dhaka city is heavily dependent on groundwater extraction where more than 87 percent of the supplied water is being extracted from this source and the rest amount from rivers. Such extensive dependency enhances a very high depletion rate of groundwater table. A research from Unnyan Onneshan published that, Dhaka city has been experiencing a sharp declination in groundwater table with more than 20 meters lower down during the last seven years at a rate of 2.81 meter per year (m/y). Considering the existing depletion rate, the study predicts that the groundwater table will go down to 120 meters by 2050. To solve this problem of water crisis and at the same time to protect the surrounding rivers, now it is the high time to take action for improving the sewage system and redesign the urban planning. As in the existing sewage system, less than one-fourth of Dhaka city area is currently under the coverage of sewerage network. In Dhaka, where there is no sewerage network, more than half of the buildings are not having any septic tank and the sewer pipelines of these buildings are directly connected either to the open drain or to the storm drainage system polluting the surface water and the environment. Though the master plan of Dhaka Water and Sewerage Authority (DWASA) proposed construction of sewerage network and treatment plants; the divisional towns and municipalities have no plan on how they would manage feacal sludge. Master plans for few small towns are in development process; but these do not have any specific proposition for faecal sludge management, said by Hasin Jahan. However, implementation of any master plan in terms of its investment, timeline and other factors are pretty uncertain. There must be proper work distribution among DWASA, RAJUK and Dhaka City Corporation. Right now more than 5 million people are directly facing the danger of water pollution in Dhaka. This number will virally increase if quick steps are not taken.