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The River Dhaleshwari, once a lifeline for farming and fishing communities at Savar is now choking with the same pollution that had devastated the Buriganga before the relocation of tanneries from Hazaribagh.

A study by the University of Dhaka reveals alarming levels of heavy metals and microbial contamination in the river, underscoring fears that the government’s much-touted relocation of tanneries from the capital’s Hazaribagh to Savar has merely shifted the problem, not solved it.

The study titled ‘Impact of the tannery industrial zone on the physicochemical and microbiological quality of the Dhaleshwari River, Bangladesh’ was published on January 15 in the Bangladesh Academy of Science journal.

The study found pathogenic organisms including E coli at 150 colony-forming units per millilitre, far above the World Health Organisation’s recommended zero CFU.

Researchers also detected lead concentrations of up to 0.07mg per litre, nearly five times higher than the WHO’s permissible limit of 0.015mg, while chromium was found at 0.1mg per litre — the upper threshold of safety.

‘What we’re seeing is the early stage of a contamination cycle that could haunt communities for generations,’ Mazharul Islam, an assistant professor of the chemistry department at the University of Dhaka, told ¶¶Òõ¾«Æ·.

Analysing 26 water samples from the river, he also warned that long-term exposure to pollutants accumulated in sediments, fish, and crops, gradually entering the food chain.

For residents, the changes are already stark.

Abul Bashar, a farmer from Lankerchar, said that the locals stopped using the river water for household needs after the tannery relocation due to frequent illness.

‘In the dry season, the water turns odorous and murky. Fish is disappearing, and cultivation has become difficult,’ he said.

Experts argue that the relocation amounted to little more than a ‘geographic transfer’ of pollution.

‘We didn’t fix the problem, we just moved it from Hazaribagh to Savar,’ said associate professor Mostafizur Rahman of Jahangirnagar University’s environmental sciences department.

At the centre of the crisis is the central effluent treatment plant at Savar, on the outskirts of Dhaka, built under the supervision of Bangladesh University of Engineering and Technology.

The facility was designed to process 25,000 cubic metres of effluent daily, but tannery output exceeds 30,000 cubic metres during peak seasons such as Eid-ul-Azha when a huge number of animals are sacrificed by Muslims.

Officials say that the CETP’s effective treatment capacity is only 14,000 cubic metres.

The plant lacks key features such as reverse osmosis technology for salt removal, an integrated grease system, and a sedimentation tank.

Its three chrome recovery units together can process only 1,050 cubic metres of chromium waste, compared with a daily output of about 5,000 cubic metres.

‘Pre-treatment is mandatory for every tannery, but none are following it,’ Md Golam Shahnewaz, managing director of the Dhaka Tannery Industrial Estate Waste Treatment Plant Company Ltd, told ¶¶Òõ¾«Æ·.

He added that poor practices, including the dumping of plastics and food waste into pipelines, raise the chemical oxygen demand and disturb pH levels in river water amid tannery-specific chemical uses.

While the CETP can temporarily store up to 80,000 cubic metres of effluent in reservoirs to delay discharge, he admitted that discharged liquid still contains 15 to 20 per cent pollutants due to installation flaws and weak oversight by the BSCIC.

However, tannery operators argue that the Bangladesh Small and Cottage Industries Corporation failed to provide adequate infrastructure for proper waste management.

‘They did not allocate enough space for effluent treatment plants so that we could conduct preliminary treatment,’ Zahidur Rahman, a leather engineer at Salma Tannery, told ¶¶Òõ¾«Æ·.

He also blamed local storage depots operating outside the estate for contributing to biological contamination.

Solid waste poses another growing concern. Tannery waste, including chromium-contaminated sludge, is often dumped openly on the banks of the Dhaleshwari, threatening both river and soil health.

There are fears that toxic leachate could seep into groundwater.

The general manager at the Planning and Research Division of BSCIC, Md Forhad Ahmed, said that the agency had launched a project titled ‘Dhaleshwari Protection: Prevention of Pollution from Tannery Waste Leachate and Soil Contamination in BSCIC Industrial City’.

‘A multi-layered pond, similar to a landfill, will be constructed to prevent runoff from reaching groundwater,’ he said.

‘The pond will be designed to collect leachate in a specific area, from where it can be transported to the CETP for treatment before being discharged,’ he added.

Meanwhile, private investors are also entering the waste recycling sector. A Chinese-owned company, Bangladesh JW Animal Protein Co Ltd, has begun collecting solid tannery waste at Savar to convert it into export-oriented products, like Gelatine and industrial protein powder.

‘JW Animal Protein will gradually collect all chrome shaving dust from the tannery estate. They are setting up a factory equipped with an effluent treatment plant on nine acres of land at Nayarhat,’ Dhaka Tannery Industrial Estate Waste Treatment Plant Company Ltd managing director Golam Shahnewaz said.