On the occasion of World Water Day 2014 Helemul Alam of The Daily Star talked to Taqsem A Khan, managing director of Wasa about various issues pertaining to water policy, its quality, availability etc. The excerpts are given below.
With the challenges of providing safe water to all and reducing dependency on ground water in the capital, country is going to observe World Water Day-2014 on March 22.
This year's theme of the World Water Day-2014 is "Water and Energy".
Though Dhaka Water Supply and Sewerage Authority (Wasa) has increased its production and achieved the target of reducing the scarcity of water but reducing the depletion of ground water is big challenge of the organization.
Currently Wasa can produce 242 crore litre water per day, of which 78 percent comes from ground water through 670 deep tube-wells and 22 percent comes from surface water through five water treatment plants.
"To reduce the depletion of the ground water we have set up a target to reduce 70 percent dependency on ground water by 2021," said Taqsem A Khan.
Each year, the groundwater level in the central area of the capital drops by 1 to 3 metres due to excessive extraction of groundwater, mentioned Taqsem.
If the dependency on ground water exists there would be a chance of landslide, he said.
According to the statistics of Bangladesh Water Development Board, the groundwater level in Mirpur fell 53.75 metres between 1991 and 2008, while the decline was 18.59 metres in Mohammadpur, 37.4 metres in Sabujbagh, 8.22 metres in Sutrapur, and 14.14 metres in Dhaka Cantonment areas during the same period.
Dhaka Wasa is going to set up three new water treatment plants to increase the use of surface water significantly by the next seven years, said the MD of Wasa.
The new plants will be set up at Gandhabpur of Rupganj, Jasaldi in Mawa and Sayedabad in Dhaka with an estimated cost of around $1.5 billion.
The construction of Gandhabpur water treatment plant is likely to begin in September, Jasaldi plant in May 2015 and Sayedabad phase-III plant in June, 2015.
The new plants will produce 140 crore litres of water per day, almost 60 percent of the current production of the Wasa, he added.
Currently, the Wasa supplies 22 percent water to the dwellers of Dhaka and Narayanganj cities from the surface sources, mainly from the Shitalakhya river.
As all the four rivers surrounding the capital are heavily polluted, the Wasa now has decided to bring water from the rivers Padma and the Jamuna for the treatment plants. The water has to be piped from 22 to 33 kilometres away from the capital, resulting in at least 15 percent increase in the project cost, according to a Wasa official.
"As the pollution of the rivers surrounding the capital is polluted hugely we are bringing the water from Padma and Jamuna," said Taqsem.
Among the four rivers surrounding the Dhaka city, the water of the Shitalakhya river is already being used. The water of the Buriganga is too polluted to be used.
As for the Balu and the Turag rivers, these not only are heavily polluted but also have shrunk so much due to mindless encroachments that their water flow remains very low during the dry season.
According to the Environment Protection Act (Amendment) 2010, the minimum required level DO for any water body to sustain aquatic species including fishes and others is 5 mg/l.
According to the Department of Environment (DoE) study, in Buriganga Dissolve Oxygen (DO) was almost nil at all locations of the river during the first five months in 2010. In 2011, it varied from 0 to 5.1 mg/1.
In Shitalakkhya no DO found at Demra ghat point from January to March in 2010. In 2011 DO varied from 0 to 6.5 mg/1.
In Turag DO was practically nil in between January and April in 2010 and 2011 and DO was found nil in all three sampling locations of Balu river—Tongi, west side of Tongi Bridge and near Jabar-Jubair textile mills, in January to May in 2010.
An official of Wasa said where the normal presence of ammonia in unpolluted river water is 2 miligram per litre (in Bangladesh 4 milligram is acceptable) but due to the huge pollution of the Shitalakhya river during dry season they found the rate of ammonia at 15 milligram per liter and above.
"We need to bring the ammonia down to 2 miligram per litre through pre-treatment unit of Sayedabad water treatment plant and then send the water to the treatment plant to treat," he said.
The intake point of the Sayedabad water treatment plant is in Sharulia of Shitalkhya river, he added.
The Wasa two years back had set up a pre-treatment unit for Sayedabad water treatment plant (phase I and II) spending Tk 160 crore due to excessive pollution of the river Shitalakhya, said another official of Wasa.
Due to huge pollution of the river Buriganga, Wasa took initiative to set up the Sayedabad water treatment plant using the water of Shitalakhya River at Sharulia point more then one decade ago as water quality of the river at that time was better, said the official.
One of the main causes of river pollution surrounding the capital is untreated industrial waste as most of the industries in and around the capital do not use effluent treatment pant and discharge its untreated industrial waste into the river and other water-bodies.
Water for poor people
The MD of Wasa said to bring the poor people under the coverage of pure drinking water they have started to bring the slums of Dhaka city under Wasa's water supply network.
He said they have a plan to bring all the 35 lakh slum dwellers under fresh water by December 2015. So far one third of them have come under the programme.
"We have also reduced system loss to 26 percent from 40 percent within the last four years by providing water to slums, replacing old pipelines and disconnecting illegal lines," he said.
"We will complete the work of replacing all the old pipelines of the city by the next two years," Taqsem added.
The writer is Senior Staff Reporter, The Daily Star.