Presented byReba Paul, Executive Secretary, BWP and

Azharul Haq, Former Managing Director, Dhaka WASA

Challenges of Water Quality Management: Case of Peripheral rivers

in Dhaka Mega City

Eye on Asia Day at World Water Week 2010Organised by Asian Development Bank

8th Sept, 2010, Stockholm, Sweden

Area: 348.57 sq.km

Population: 12 million.

Estimated future Population: 21 Million by 2025

Expanded area: 1000 sq km

Demographic Information of Dhaka City

Southernpart

River systems in and around Dhaka city

Five Rivers Peripheral :Buriganga,Dhaleswari,

Turag, Balu, Sitalakhya and Tongi,

Padma (Ganga), Jamuna (Brahmmaputra) and

MeghnaConnected to

The five peripheral rivers are receivers of stormwater, municipal and industrial wastewater and sewage from Dhaka City

Causes of Water Quality in Dhaka Rivers Indiscriminate disposal of untreated industrial

effluents, municipal and domestic waste and sewage

Low coverage of sewerage facility (Only 30%) Unabated pollution, encroachment and fill up of

canals, lakes, water bodies and wetlands by the land grabbers and industries.

Reduced water flow in the rivers during dry

season. Siltation and reduced self purification capacity

of the rivers. Weak Institutions Lack of coordination among development

agencies.

Challenges of Water Quality Management

Population growth Rapid urbanisation and industrialisation Migration of people from rural to urban Limited land for expansion. Lack of urban planning Limited sewerage system. Old pipe network Lack of fund Lack of leadership

There are 300 outfalls of domestic and industrial effluents.

Nine outfalls are the major polluters.

Effluents are discharged into the rivers indiscriminately without any treatment.

Major Sources of Pollution

Water Pollution

Encroachment of rivers and water bodies

Sate of rivers in Dhaka

Pagla STP

Population Present Capacity

Sewage Generation

(million) (Mm3/d) (Mm3/d)2004 10.58 0.12 1.062005 11.08 0.12 1.112010 13.59 0.12 1.362015 16.67 0.12 1.672020 20.06 0.12 2.012025 24.26 0.12 2.43

Year

Pagla STP (only sewage treatment plant) has capacity to treat 10% of generated sewage of Dhaka city.

It has an installed capacity of treating 0.12 Mm3/d, which is very less than the present city load.

Pagla STP

Tongi Khal

Buriganga R.

Turag R.

Lakhya R.

Water Quality Profile: Turag-Buriganga-Dhaleswari

Source: IWM

Longitudinal Dissolved Oxygen Profile(Turag-Buriganga-Dhaleswari River)

0

1

2

3

4

5

6

7

0 5 10 15 20 25 30 35 40 45 50 55 60

Distance from Ashulia Landing Station Bridge (km)

DO

(mg/

l)

DO at Neap Tide on 19-20 Feb 05 DO at Spring Tide on 26-27 Feb 05 DO at Neap Tide on 13-14 Mar 05 DO at Spring Tide on 20-21 Mar 05

Turag Buriganga DhaleswariTongi Khal

Ashulia Landing Station Bridge

Kalagachia

Tongi R.Bazar

Dissolved Oxygen (DO) level falling to zero;Aquatic life under severe threat

DistanceDO Level

BOD Loadings for All Industrial Clusters

Computed BOD Loadings of All Industrials Clusters

0

100,000

200,000

300,000

400,000

500,000

600,000

2006 2010 2015

Year

Load

in k

g/da

y

Total Generate Load (kg/d) Industrial Load (kg/d)

Domestic Load (kg/d) Domestic Load Retained in situ (kg/d)

Industrial effluent BOD accounts for around 50-60% of the Total Effluent BOD

Total load

Industrial load

Domestic load at outfall

Domestic load retained

Source: IWM

Impacts of poor water quality

Affecting human health, environment, economy, ecosystem and biodiversity.

Put serious threat to city water supply and security.

Added cost to water treatment.

Holding country from achieving MDGs related to water supply, sanitation and health.

City Water Supply and Demand

Source: DWASA+IWM

Present Demand : 2470 MLD

Present Supply: 1930 MLD

83% comes from GW and 23% comes from 4 SWTPs

Future Water Demand: 4990 MLD by 2030

Groundwater depletion

•2-3m/year lowering of WT

•No further abstraction from upper aquifer (100-200m) is viable.

•45 DTWs in deeper aquifer are in operation and another 50 DTWs have been planned.

Source: DWASA + IWM

Policy makers (Water Resources, Industry and Shipping Ministers and Local Government) and Experts discussing

water security issues in Dhaka city.

High Level Dialogue on 'Surface Water: the Most Potential Future Alternative for Water Supply in Dhaka City’.

Participation of all stakeholders from government and non-government organizations, minisers, member of parliament (MPs) , international organizations, private agencies, academic institutions, print and electronic media and individual water experts.

• All medium and large industries need to install ETPs.• All small industries to shift to identified industrial clusters.• All industries should adopt cleaner production

technologies to reduce generation of pollutants• The river beds need to be dredged to remove polluted soil

and sludge. • Removal of river encroachment.• Shifting of Hazaribagh tanneries to Hemayetpur.

Necessary measures to control pollution of water

• Rehabilitation of the existing STP and installation of five planned STPs.

• Buriganga flow augmentation from large rivers.• Rehabilitation and extension of the existing sewerage

network• Rehabilitation and expansion of the Pagla STP• Demand management to reduce overuse or

wastage of water• Implementation of new Sewage Treatment Plants

according to DWASA Master Plan

Government’s Recent Initiative

• Task Force formed by the Government.• Rivers declared as ‘Ecologically Critical Areas’.• Decision on shifting tannery industry outside the

capital.• Cleaning of Buriganga and Turag has already

started and helped launching water bus servces.

•Court has directed deployment of law enforcing agencies to prevent dumping of wastes into the rivers.

•Ministry of Environment has directed all the polluters to install Effluent Treatment Plants (ETP).

Good Start BUT!

Ultimate success of cleaning the rivers depends on disposal of dredged materials in suitable place and control of industrial and

other pollution.

Diabari STP

Uttarkhan STP

Baidertek STP

Kamrangirchar STP

Pagla STP

Tongi STP

Five new Sewage treatment plants are an

immediate need in Dhaka and Tongi to

reduce river pollution .

Cost of 5 sewage treatment plants is about

$600 million

Source: DWASA