The government has already spent over Tk 21 crore on its much-hyped Buriganga-Turag River Cleaning Project, but the rivers remain contaminated with toxic wastes, as the pollution sources could not be plugged.
According to a recent water quality test, the amount of dissolved oxygen (DO), which determines the degree of water pollution, is still too low for aquatic lives to survive in the Buriganga.
The Department of Environment conducted the test at five points in the river in December.
"Yes, the water quality is not good yet, as we couldn't stop the sources of liquid waste," said Abdus Sobhan, deputy director general of DoE.
Hazaribagh tanneries are still there, Sobhan said adding that excreta of millions of city dwellers are still emptying into the rivers through Wasa storm sewers every day.
"So it's no surprise the quality of the river water is not improving," he observed.
With the river pollution continuing unabated, the dependence on groundwater grows.
Around 85 percent of the city's water demand is met from groundwater source, as most of the surface water is contaminated. This heavy reliance on groundwater causes the water table to lower three to four metres on average every year, said sources in Dhaka Water and Sewerage Authority (Wasa).
It was to solve this scarcity of safe surface water the government undertook the Buriganga-Turag River Cleaning Project.
Bangladesh Inland Water Transport Authority began implementing the first phase of the project in May last year and has already spent over Tk 21 crore.
The BIWTA was supposed to clean three kilometres of the Buriganga from Babubazar to Kamrangirchar and one kilometre of the Turag at Tongi point.
It is spending Tk 285 to dredge and grab per cubic metre of garbage from the riverbed and more than that to collect the floating and solid garbage from the riverbank.
"We know the water quality is not improved by this project. So we're going slowly," says an official requesting anonymity.
Asked why they are spending public money if the project is not yielding satisfying results, the BIWTA official replies, "Tk 21.5 crore has already been allocated in this project. So we are continuing with our work."
Currently, there are three dredgers and one grabber working at Tongi point, he adds.
According to the project proposal, the riverbeds in the capital are clogged with thick layers of polythene, coconut shells, plastic, mud and bricks.
They were supposed to excavate two metres from the edge of the riverbeds and one metre from the middle, says the project proposal, which was funded from the climate change trust fund generated by government revenue.
The Department of Environment tested the water of the Buriganga collecting it from five different points in December last year.
Laboratory analysis of the samples shows that presence of DO was between 0.50-0.84 mgs per litre (mg/L), while standard surface water is 5 mg/L in Bangladesh.
Besides, presence of BOD was recorded to be between 42-19 mg/L and pH was identified to be between 7 and 7.5.
The standard DO requirement for fish and other aquatic lives is 5 mg/L, whereas BOD and pH requirements are 10 mg/L and 6.5 respectively as per the set standard of Bangladesh.
Earlier, researchers from Bangladesh University of Engineering and Technology (Buet) found that oxygen levels were 0.7 and 0.25 at Chadnighat point, 0.27 and 0.63 in Norai near Trimohini, and 0.27 and 0.63 in the Turag at Tongi before and after the monsoon respectively.
A three-year research finds that some invertebrates and small organisms come to life in these rivers when water flow increases in the rains. But these life forms completely disappear in the dry season, the researchers add.
The Institute of Water Modelling (IWM) and the World Bank conducted a survey of pollution in Dhaka river waters in 2007 that showed there are over 300 various effluent discharge outlets in the capital and Narayanganj.
Of these, 19 outlets carry mixed flows of industrial and household waste into the rivers around the capital.
The study also observed that the groundwater system is being contaminated more in areas where aquifers are recharged from the riverbeds.
However, the DoE continues to conduct a drive against pollution and fined over 100 industries for not installing Effluent Treatment Plant (ETP) what is mandatory as per the environment law.
Still, over 300 major industrial units are dumping their liquid waste into the rivers, say officials of the environmental watchdog.
Dr Sobhan, also a member of the project's monitoring committee, suggests continuing with the project. He said, "If they remove one cubic metre of garbage from the river, space for one cubic metre of water will increase."
Besides, he added, measures should be taken to stop dumping of human excreta into the rivers.
News Source: The Daily Star