Deluge in Dhaka: Are the hopes being flooded away?

Dr. Ishrat Islam

"Downpour deluges Dhaka” becomes a very common heading for most of the daily newspapers after a three/four hour shower in Dhaka. Such water logging/flooding is often termed as urban flooding. Average Rainfall in Dhaka is 2,000 mm per annum and 70 percent of this rain comes in April to September. In the recent time, the pattern of rainfall has been changing and we are observing heavy rainfall for a longer period. We can still remember the collapse of entire city during an uninterrupted rainfall for two days in September 2004. It is predicted by the researchers that, heavy rainfall for longer period would be one of the impacts of climate change in the coming days. After a heavy shower, most of the city functions collapse, industries and employment centers face severe loss due to absence of workers, road surfaces are damaged and so on. Our awareness and activities in response to such urban crisis is mostly limited to the seminar rooms, workshops and television “Talk Shows” because we failed to address this issue at field level with due importance and exigency.

Let's see how we have entered into such urban disaster. Is it our fate or outcome of our act? Urban water logging is associated with a number of issues. I like to focus on one of the most pertinent factors; unplanned expansion of our beloved city Dhaka. The way this city is growing, is alarming. It leads to the increase of impervious surfaces, filling up of water bodies and low-lying areas, development of infrastructure with little cognizance to the natural network of water bodies, poor management of solid waste etc. The historians once symbolize this city as Venice of the East, but today there are hardly any natural canals and lakes visible with clear flow of water. In fact, many of the natural canals and wetland are no more in existence. Even the rivers are encroached and polluted at such an extent that no living organism can survive there. To get rid of flooding, the access rainwater required to be drained out quickly through man-made and natural system of drainage network. But man-made drainage system for Dhaka city is far below the requirement and its maintenance is poor. With our short sighted view of development, we had significantly disrupted the natural drainage network of the city, which was the most precious resource. The value of these water bodies was intelligently perceived by the earlier settlers of this city. They took entire advantages of the water-bodies for transportation, drainage, food production and security. The renowned British town planner Sir Patrick Geddes prepared a plan for Dhaka in 1917. In this plan, he specifically mentioned about the importance of the canals and water bodies of Dhaka and suggested to incorporate these in the cityscape for drainage, transportation and recreational purpose. Later plans for Dhaka like the 1959 master plan, Structure Plan of 1995-2015, all have specific policies to conserve the wetlands of Dhaka. Particularly, Flood Action Plan for Dhaka (FAP 8A and 8B) came up with specific proposals to deal with the flooding problem of Dhaka. FAP gave list of canals which were required to be restored. It mentioned about flood flow zones and retention pond areas. These proposals were later incorporated in the Structure Plan and partly in Detailed Area Plan (DAP). By the time DAP has been published few months back, a significant amount of flood flow zones, canals have already been filled up by private, and in some occasion by public agencies, despite of these planning documents and legal bindings. We are losing our water bodies not because of our ignorance and lack of planning vision. The concerned planners, professionals and environmentalist have been persistently working towards conservation of the water bodies of Dhaka and informing the authorities about the adverse impacts. The contemporary culture of grabbing wetlands, polluting water bodies by waste disposal is not only the failure of regulatory authorities rather the problem is deep rooted within the socio-political and economic context of the society. Our vision for this city, our planning goals of this city is never translated into actions.

People are talking about sustainable development around the globe, and getting prepared to keep pace with fast rate of urbanization, population pressure and in some cases, to combat adverse impacts of climate change. But in case of Dhaka and other cities of Bangladesh, how far are we translating these visions into action? Let me share some research data with the readers (research conducted in the Department of URP, BUET). For the western part of Dhaka, Flood Action Plan (FAP 8B) proposed the cleaning and restoration of 21 khals (canals) of 78 km in length. But it is very unfortunate to see the research findings that of the 11 khals of western part of Dhaka, nearly 50% or more are already encroached and some have disappeared entirely. The designated retention ponds are at the threat of land filling. In the eastern part Dhaka, it would be a disaster if we allow land development projects before construction of Eastern embankment and keeping sufficient amount of retention pond areas and canals as suggested in the DAP. It is very difficult to predict about the completion time of the Eastern embankment due to financial and administrative complexities and thus, the regulatory authorities should take cautious step while giving approval to the land development projects in the eastern part of Dhaka.

In addition to the large scales depletion of open spaces and water bodies of Dhaka, let's see how we are aggravating the flood problem at individual plot level. With the boom of construction industry in the last fifteen years, more and more surface areas have become paved and thus rain water cannot penetrate into the ground. As a result, storm water from all the built structures are drained out to the main system. The drainage system of Dhaka fails to handle such huge volume of surface runoff of rain water during peak hours of rainfall which eventually causes flooding. But in the past, most of the plots had open spaces and thus, a significant portion of the rain water could infiltrate into the ground. We can recall the spouts of the old buildings of Dhaka, pouring down rainwater from the roof into the open space of the plot. In the contemporary practice of building designs, there is little attempt for such on site management of rain water.

Every city dweller bear some sort of economic, social and health cost directly and indirectly during flood. Particularly, the poor suffer much, they are deprived of their daily earnings, often displaced from their shanty shelters located in the low-lying areas, go through health hazards and thus loose their small savings and assets to cope with the disaster. The cumulative cost of such flooding is huge, but we fail to comprehend it. We never calculate the cost of such urban disaster while we undertake development projects for the city. As a result, the cost of flooding becomes an unavoidable pressure to the poor economy of the country and its people.

In order to address the flooding problem of Dhaka, there is no other option than determining strategies for efficient management of the wetlands. Wetland management strategies require incorporation of various components like: (i) Land use planning policies; (ii) Development control tools; (iii) Taxation policies to regulate development; (iv) Proper planning for development of infrastructure to attract highland areas for future development; (v) Institutional capacity building to exercise the rules and regulations; (iv) Dialogue among the stakeholders of wetland and finally the political will and social commitment of the government. To manage the rainwater through rainwater harvesting can reduce the flooding problem to some extent and at the same time can address our water crisis problem in dry season. It is necessary to include the rain water harvesting component in the building code. It is inspiring to see that even the common people are aware of the value of the water resources of Dhaka. The bold stand of the government regarding DAP, cleaning of Buriganga River, the schemes to restore canals certainly indicate that the policy makers are committed and are taking cautious steps. But at the same time, success of these efforts become blurred when authorities become tight-lipped in some special cases. As a resident of Dhaka, I try to become hopeful sometimes but soon, get frustrated to see how we are destroying our resources and compromising the environmental and social justice issues in the name of economic development for a specific group of the society.

The author is Associate Professor, Department of Urban & Regional Planning, BUET, Dhaka