Although the Environment Cell of Dhaka Water Supply and Sewerage Authority (Wasa) in 2003 detected 36 industrial plants in Tejgaon Industrial Area of the capital as the main polluters of the Balu river and linked canals, no action has yet been taken against them. The list comprises 30 washing and dyeing factories, 4 soap factories, and 2 ink producing factories. A high official of Wasa on condition of anonymity told the Daily Star, "In April 2007 the Ministry of Industries, and the Ministry of Environment and Forest jointly told representatives of business communities that unless they install effluent treatment plants (ETP) in their factories before October 31 of the same year, supply of electricity, gas and water would be disconnected." "However, no such action has yet been taken against the violators of government rules, although most of the 150 industrial plants in Tejgaon Industrial Area are operating without having any ETP," he added. Everyday 3,500 cubic metres of wastewater containing waste load of 1,850 kilogram (kg) with high level of biochemical oxygen demand (BOD) gets drained into the low lying lands of eastern Dhaka from the industrial zone, which subsequently gets into the Balu river via Begunbari and Norai canals, causing serious damage to the adjacent paddy fields of the area, states the 'Study on Alternative Location of the Intake of Saidabad Water Treatment Plant', commissioned by Wasa in May 2006. "Pitch black effluents from Tejgaon Industrial Area containing heavy metals such as lead, cadmium, and magnesium are causing serious pollution of Begunbari and Narai canals, leading to pollution of the Balu river, one of the major sources of water for Saidabad Water Treatment Plant", said AKM Shahiduddin, executive engineer of the drainage department of Wasa. Saidabad Water Treatment Plant is the major source of treated safe water for the capital. "Human waste and industrial waste get dumped into Begunbari canal. Human waste is not that harmful for the environment since it is bio-degradable. But effluents from factories containing toxic materials deplete the level of oxygen in river water, and it is really difficult to treat waste water containing such toxic substances," said Waliullah Sikder, project director of the Rain Water Logging Project of Wasa. The Environment Cell of Wasa sent samples of effluents that are dumped into Begunbari canal from Tejgaon Industrial Area, to the laboratory of the environmental engineering department of the Bangladesh University of Engineering and Technology (Buet), for physical and chemical analysis in 2003. The report revealed that the total suspended solids (TSS) in the samples were 16 times higher than the level allowed by international standards while the BOD was 11 times higher than the standards, meaning the effluents may cause serious ecological and environmental damage by polluting the water of Balu river and the canals. The dumped effluents deplete the oxygen level in the water bodies to a point when no creature may survive in that water. Nironjon Das, an ageing fisherman of Rajakhali, a village on the bank of river Balu in Demra, said, "We get only a few puti fish from the river now and that also only during the monsoon, but a variety of fish like foli, chital, bailla and boyal were available in the Balu before." "The change in the environment of the river has also totally changed our livelihood. Many fishermen are now engaged in other professions", he added. Residents of the area complained that they cannot use the polluted river water for household chores either. "The pitch black malodorous water gives itching skin rashes," said Ambia Begum. Some four kilometres upstream from Rajakhali of Itkhola near Dasherkandi, where Narai canal meets the Balu river, the scenario is even worse. "It's really difficult to survive next to Narai canal. We haven't been using water from the canal for the last 12 years. Moreover, it has become a breeding ground for a huge quantity of mosquitoes. The stinky canal has become a curse for us," said M Jahangir Alam, a local resident. The 36 major polluters in Tejgaon Industrial Zone detected by Wasa had been established in the late 1980s, and they have been polluting the nearby canals, rivers, and the greater adjacent area since then. Akhtar Hossain, a resident of Trimohoni where large amounts of the boro variety of rice is traditionally cultivated in the low lying areas, said, "The harvest rate has decreased over the last few years. Use of water from Narai canal for irrigation might be the reason for it. I can't comprehend why Wasa set up a water treatment plant here for supplying safe water to the city." Engineers of Dhaka Wasa also said treating water collected from the Balu river is very difficult and cost intensive for Saidabad Water Treatment Plant, especially during the dry season, because the plant has to use extra chlorine to treat the extremely polluted water. The treated water also smells of chlorine due to required heavy use of the chemical. About possible solutions to the problem, a high official of Wasa said, "After the completion of Begunbari-Hatirjhil Beautification Project, no drain will flow into Begunbari canal. We have asked for a fund to set up a waste treatment plant at Dasherkandi to preserve the water of river Balu, and we decided to start collecting water from the Meghna river for treatment in Saidabad Water Treatment Plant." "But, installation of ETPs in industrial plants or installation of CEPTs (Common Effluent Treatment Plant) at five points of Tejgaon Industrial Area is a must for ameliorating environmental pollution in greater Dhaka," he added.