Editing Dhaka (section)

=== Environmental pollution ===
{{See also|Environmental issues in Bangladesh}}
[[File:Pollution by a factory on the bank of the Buriganga near Dhaka 04.jpg|thumb|Pollution by a factory on the bank of the [[Buriganga]] near Dhaka in 2020]]
Increasing air and water pollution affects public health and the quality of life in the city.<ref name="Geo2">{{Cite news |last=Mondal |first=M. Abdul Latif |date=27 September 2006 |title=Our Cities: 15th Anniversary Special |url=http://www.thedailystar.net/suppliments/2006/15thanniv/ourcities/ourcities28.htm |url-status=dead |archive-url=https://web.archive.org/web/20070302043917/http://www.thedailystar.net/suppliments/2006/15thanniv/ourcities/ourcities28.htm |archive-date=2 March 2007 |access-date=27 September 2006 |work=The Daily Star}}</ref> The [[air pollution]] is caused for example by vehicle traffic and congestion. Also, due to the unregulated manufacturing of [[brick]]s and other causes, Dhaka has very high levels of fine particulate matter ([[PM2.5]]) air pollution.<ref name="UD9518">{{Cite news |last=Sohara Mehroze Shachi |date=5 September 2018 |title=Bangladesh's Air Pollution Problem Grows, Brick by Brick |url=https://undark.org/article/air-pollution-dhaka/ |url-status=live |archive-url=https://web.archive.org/web/20180907141106/https://undark.org/article/air-pollution-dhaka/ |archive-date=7 September 2018 |access-date=7 September 2018 |work=Undark |quote=The kiln operations alone – while representing just 1 percent of the country's GDP – generate nearly 60 percent of the particulate pollution in Dhaka, according to Bangladesh's Department of Environment (DOE).}}</ref>

[[Water pollution]] is caused by the discharge of municipal wastewater from households and industry without treatment. As of 2011 only 20% of the city is connected to a [[Sewerage|sewer system]], whereas 80% is not connected.<ref name=":1" /> As a result, the rivers in Dhaka have severe [[pathogen]] pollution, as indicated by the [[fecal coliform]] count that is several hundred times higher than the recommended national and international standards of less than 200 [[Colony-forming unit|cfu]] per litre for bathing and swimming.<ref name=":2" /> Chemical surveys in the rivers near Dhaka show extremely high organic pollution loading, high [[Ammonia pollution|ammonia]], and very low [[dissolved oxygen]] levels, which are close to zero in the dry season.<ref name=":02" />

In addition to the organic and pathogen pollution load from the 1.2 million m<sup>3</sup> of untreated sewage, the rivers receive about 60,000 m<sup>3</sup> of industrial effluent every day from nine major industrial clusters (as of 2021).<ref name=":2" /> There are an estimated 500–700 wet processing and [[dyeing]] [[Textile factory|textile factories]] releasing a range of chemicals including salts, dyes and bleaches, and 155 [[tanneries]] discharging [[heavy metals]], including [[chromium]].<ref name=":2" />

Four of the rivers surrounding Dhaka—[[Buriganga River|Buriganaga]], [[Shitalakshya River|Sitalakhya]], [[Balu River|Balu]] and [[Turag River|Turag]]—are so polluted that they have been declared as ''ecologically critical areas'' in 2009 by the Department of Environment. This makes them unsuitable for any human use.<ref name=":2" /> Nevertheless, people living in low-income and slum areas still have a lot of direct contact with river water, exposing them to health risks. They use river water for dish washing, laundry, cleaning fish and vegetables, and personal washing, washing and dyeing [[denim]], washing fish baskets or plastic sheets, collecting plastic waste and fishing.<ref name=":2" /> As a result, many of the immediate environmental burdens of river pollution are borne by these low-income residents.<ref name=":2" />

Water bodies and [[wetland]]s around Dhaka are facing destruction as these are being filled up to construct multi-storied buildings and other real estate developments. Coupled with pollution, such erosion of natural habitats threatens to destroy much of the regional biodiversity.<ref name="Geo2" />