Management of fecal sludge crucial to save waterbodies: speakers

To save canals, rivers and waterbodies in Dhaka, fecal sludge management is very important and authorities should take immediate steps for its proper management, said speakers at a workshop yesterday.

"Seventy-one percent household latrines directly or indirectly (85 percent in slums) discharge to open drains, leading to pollution of lakes and canals within the city," said Prof Dr Mujibur Rahman of Buet in his online presentation, held at a city hotel.

Dhaka North City Corporation (DNCC) organised the workshop on sewerage management where representatives of Rajdhani Unnayan Kartripakkha (Rajuk), Wasa, Department of Environment, architects, planners and NGOs took part.

Prof Mujibur said instead of constructing septic tanks, households in Dhaka often directly connected their toilets to storm drainage systems, although only rainwater is supposed to go through the system.

"Many septic tanks and soakaways do not work in Dhaka because of low soil infiltration capacity. Septic tanks in most households suffer from design and construction inadequacy, resulting in shorter hydraulic detention time and consequently less sludge deposition in the tanks," said Mujibur.

He suggested to procure land for fecal sludge treatment immediately by authorities concerned, and taking initiative to construct, rehabilitation or retrofitting of septic tanks.

Giving a timeline to city dwellers to construct their own septic tanks or soakaways, DNCC mayor Md Atiqul Islam -- who chaired the programme -- said they have served a public notice to construct own septic tanks in every building by March 31, otherwise city corporation will take action.

He said the condition of lakes and canals are extremely polluted due to the sewage that fish cannot survive in these.

"We want to make all the lakes -- Gulshan, Banani, Baridhara and Uttara -- lakes of clean water where fish will be able to survive; for this, we are urging the government to hand those over to us," said Atiqul.

Speaking as chief guest, LGRD minister Md Tazul Islam said there are 39 canals in Dhaka city and if it is possible to develop those after recovering from encroachers, Dhaka will be a city like Italy's famous Venice.

About the lake handover issue, the minister said he has already given instruction to authorities concerned to take necessary steps, and more work will be done in this regard to hand over those if necessary.

Managing director of Wasa Taqsem A Khan said they will construct five sewage treatment plants along with a network of pipeline within 2027, following the sewage master plan which was prepared in 2014.

After constructing those plants, 90 percent areas will come under sewerage network while 10 percent more will need for on-site sewage systems, he said.

Wasa's lone waste treatment plant at Pagla has a capacity of treating 1.20 lakh cubic metres of sewage a day but it now treats only one-third its capacity due to dilapidated condition of the networks linked to it, said Wasa sources.

Proposing a system where the two city corporations give occupancy certificates instead of Rajuk, architect Iqbal Habib -- joint secretary of Bangladesh Paribesh Andolon -- said Rajuk does not have capacity to monitor it, as they have already failed to stop deviation while constructing buildings.

When people are obliged to take and renew occupancy certificates, they will be forced to set up their own septic tanks or soakaways at their buildings, he said.

Architect Mubasshar Hussain, president of Institute of Architects of Bangladesh, said there is no country in the world where its capital is surrounded by five rivers. But fortunately, Dhaka has five rivers around it.

"But we are in competition to destroy and pollute it," he lamented.