Approaches to restore water quality of Buriganga river

Abstract

Over the last few decades environment and its pollution is the governing concern for the human being in this planet. People become conscious about the changing of their surrounding. Global warming, Acid rain are now very familiar to us. Still lot of work to be done for mass people awareness, which is very crucial for the eountry Iike ours. People here arc so uneducated thnt few of them nrc conscious nbollt the environment and its changing. But environment is degraded by day by day the weight of over crowed people. One of such example is the Buriganga River. I3uriganga River which encompasses south-western periphery of Dhaka city receives uncontrolled discharge of pollution, solid waste, sewage and wastewaters discharged from domestic, commercial and industrial activities of the city. These waste materials are tremendously deteriorating thc water quality of the Buriganga River. The contamination level reaches at such an alarming stage during dry periods that not only the ecosystem in the river collapse but also the water treatment plants of the city water supply system developed based on the rivcr water, virtually losses their expected quality of production. Hence of restore the waleI' quality of the Buriganga is crucial for its sustainability. This study on Buriganga is approaches to restore water quality of this river, which includes possible remedial measures to prohibit of water pollution such as physical, chemical and biological pollution of the river. This study has focuscd on the present scenario of water quality, historical trend of water quality and perccnt increase of BOD loading. Data of water quality analysis in biological and chemical parameters are presented, analyzed in tabular and graphical form in this study. It is vivid the water pollution increased tremendously over the last few decades and the river Buriganga is going to be a cannel carrying polluted water. The crosssectional area, depth reduces by tilling waste loads day by day and some where increases by unplanned dredging. Shrinking of river bed is found due to the heavy BOD load, sedimentation and bank encroachment. From 1968 to 2007 maximum BODs of the rivcr at Ilazaribagh area increases from 0.8 to 60 mg/I and DO reaches 6.7 mg/I to zero in most places. BOD loading from industrial origin has increased at all industrial clusters from 1994 to 2006. The increase of BOD load is 37% in Tongi, 82 % in Hazaribagh, and 87% in Narayanganj. Formulation of different types of approaches and management programs is very essential and important in order to restore the water quality of the Buriganga River. As Hazaribagh tanneries are responsible for causing a major pollution in the Buriganga river by the contribution of toxic and persistent pollutants, an' Effluent Treatment Plant (ETP) should be established to treat the tannery waste or Tannery industries should be shifted. Moreover, proper treatments of domestic and industrial wastes are needed before discharge in the Buriganga. Proper solid waste management of the area is to be handled properly. Proper dredging and eviction of encroachers are emphasized to improve the water quality of the Buriganga river.