Septic tank for each building won’t save river: Experts

In the absence of an adequate sewage network, Dhaka city house owners connect their sewerage pipelines to the storm water drains that ultimately carry the sewage to the rivers around the capital.

Now the Dhaka North City Corporation has told the house owners that they have to disconnect such connections by March 31 and build their own septic tanks.

On the surface of it, the order sounds brilliant to save the rivers. But in reality, this will have no effect as ultimately when the septic tanks will fill up, they will be cleaned and the sewage will be dumped into storm water drains as the practice is now.

This is because Dhaka city has only 18% of its area covered by a sewage system that flows to the lone solid waste treatment plant in Pagla of Narayanganj built back in 1978.

But that only tells part of the story as many of the sewer lines have broken down and so although the treatment plant has a capacity of treating up to 120 million litres of waste a day, only about 40 million litres flow into it, as the 2012 Sewerage Master Plan has pointed out.

This means 95% of the waste you produce in your toilet go untreated into the rivers and water bodies.

Col ANM Foyezur Rahman, head of the environment department at the Military Institute of Science and Technology (MIST), said sewage produced by only 2% of the population of the capital is being treated before being dumped into the rivers. However, Professor Md Mujibur Rahman said the figure of the population covered by the sewage system is around 1.25%.    

Iqbal Habib, an architect and joint secretary of the Bangladesh Poribesh Andolon, said, "Not septic tanks, but building sewerage networks and treatment plants is the ultimate solution. One will lose his investment in septic tanks if sewer lines are installed in the near future. We need to fix our plan first and then go through it by coordinating all the institutions concerned."

Iqbal Habib said a few families used to live in a building in the '60s and a septic tank was enough to manage their wastes.

"But now 40-50 families live in a high-rise building. A septic tank for such establishment is not the solution while the Dhaka Water Supply and Sewerage Authority (Wasa) does not collect it despite taking sewerage charge," said Iqbal Habib, adding, "Imposing a fine for not having a septic tank is injustice."

Meanwhile, Adil Mohammad Khan, secretary of the Bangladesh Institute of Planners (BIP), said if people set up septic tanks, the authorities will have to ensure cleaning up those regularly.

Adil Khan also said human waste can be reused in different ways such as turning it into compost.

While contacted, Dhaka North Chief Waste Management Officer Commodore M Saidur Rahman said building owners would have to clean their septic tanks on their own.

"We are working on how the waste could be managed. Third parties might be tasked for the management," he said.

No such plan has so far been finalized. The local government ministry on Sunday convened a meeting of city officials and urban academics to find out a solution for the city's sewage management.

Meanwhile, Dhaka South City Corporation officials said like Dhaka North, they will take action against those who will not have septic tanks and dump sewage into the water bodies.

But several house owners said septic tanks become useless as soon as the households get connected to the sewerage network.

Zakaria Tanvir, a house owner of Dhaka's Shewrapara, said, "I made a septic tank during the construction of my house. Later, Wasa constructed the sewerage network in this locality 10-12 years ago. Since then, my septic tank has remained useless."

Harun-ur Rashid, a cleaner of the Dhaka North City Corporation, said they dump the sewage into the drains after cleaning a septic tank. The solid waste is dumped in the city corporation's landfill with kitchen waste.

Harun and other cleaners of the city also do the same thing as there is no facility to dump or treat human waste collected from the septic tanks.

The cleaners said many of their colleagues died inhaling toxic gas while cleaning the septic tanks. 

According to the Bangladesh Institute of Labour Studies, at least 130 people died inhaling toxic gas across the country while cleaning septic tanks in the last five years, while some 93 sustained injuries.

According to Wasa officials, around 250 crore litres of liquid waste are produced in Dhaka daily while Dhaka Wasa sewage treatment covers 18% of the population. 

Taqsem A Khan, managing director of DWASA, said, "We have achieved 100% self-sufficiency in water supply first. Now we focus on the construction and maintenance of the sewerage system, which depends on donor agency funding."   

"We have a master plan, and we are going to build five different sewage treatment plants in the city in the next seven to ten years. Once the projects are concluded, 100% sewage will be treated," he said.

"Already construction of Dasherkandi treatment plant is going on to cover the eastern part of Dhaka. After the project completion in one and half years, waste from septic tanks will be treated there.    

"At the same time, land acquisition is on for Uttara treatment plant which will cover the northern part of the city. And the work for the second phase of the Pagla treatment plant has been started," he added.