Improved Services

DWASA’s strategies to reduce water losses in Dhaka

The Dhaka Water Supply and Sewerage Authority (DWASA) was established in 1963 to supply water and provide sewage disposal services to the people of Dhaka. In 1990, the water supply service of Narayangonj city also came under the purview of DWASA. The utility’s activities have been reorganised by the Water Supply and Sewerage Authority Act, 1996. According to this act, DWASA operates as an autonomous body.

Dhaka, the capital of Bangladesh, is the most populated city in the country. The Greater Dhaka area had a population of more than 18 million in 2016, of which about 8.5 million reside in the city area. Before 2004, about 80 per cent of Dhaka’s residents used groundwater, mostly from deep tube wells, while the rest used treated surface water. Most of Dhaka’s water-related problems were centred around its overdependence on groundwater. The lack of surface water and infrastructure to deliver clean or 24×7 water supply was one of the key reasons for unsustainable reliance on groundwater. Besides, the public had resorted to using suction pumps  as a coping mechanism that was also responsible for the dependence on groundwater.

The common issues faced by DWASA in the urban water supply and sanitation sector are as follows:

  • Poor quality of water distribution network and high water losses: A pilot project in the Manikdi area of Dhaka revealed that household connections were substandard and leaking, and that physical water losses accounted for more than 50 per cent of the total losses. Further, only 59 per cent of the household connections had water meters to measure consumption. Moreover, installed meters were often inaccurate or inaccessible, making it practically impossible to manage water efficiently.
  • Low quality and lack of reliability of water supply and poor service delivery: The quality of groundwater supplied through pipes was substandard. Water quality aside, intermittent water supply worsened the problem by creating a vacuum in the absence of supply, leading to contamination.
  • Limited coverage of slum dwellers: Around 15 per cent of the population in the DWASA service area was living in slums (2007 estimates). A significant number of slum dwellers had illegal connections and the number is expected to increase to 4 million by 2025 in the absence of government intervention and change in policy.
  • Financially unsustainable utility: Network haemorrhage, meter defects and illegal water connections made it difficult for DWASA to collect the required revenues to carry out regular operations and maintenance, and expansion of water pipes. In addition, only half of the water supplied to the networks was billed and only 62 per cent of the water billed was collected.
  • Inadequate supply of clean water to meet the growing demand: More than 80 per cent of Dhaka’s water supply came from groundwater. As per reports, by 2007, the upper aquifer of Dhaka had already exceeded its withdrawal limit. As a result, almost half of the deep tube wells supplying water to Dhaka were expected to dry up by 2013.

In view of Dhaka’s ever-increasing water woes, the Bangladesh Government of listed water supply and sanitation among the seven priorities in its National Poverty Reduction Strategy. The strategy was aligned with the United Nations Millennium Development Goals. In its 2006 sector development plan for water supply and sanitation, the Bangladesh government highlighted its citizens’ basic entitlements, the way utilities should operate and their financial needs. Following this, it adopted the Dhaka Water Supply Sector Development Program and entered into a policy-based loan agreement with the Asian Development Bank (ADB). The agreement was signed based on the ambitious reform programme to improve the entire urban water sector and aimed at enabling DWASA to operate more effectively and sustainably. The reform programme was based on four broad pillars:

  • Improving local governance and strengthening the local institutional framework.
  • Preparing a sector strategy for demand-side management.
  • Improving financial sustainability.
  • Strengthening DWASA’s governance, organisational structure and financial management capacity.

The programme was implemented in 2008. The project loan covered the major components improving and expanding the distribution system through district metered areas (DMAs), strengthening the DWASA and improving its institutional capacity, and controlling water waste and raising public awareness regarding water conservation.

In order to create DMAs in the Dhaka service area, DWASA rehabilitated primary and secondary networks including lining and replacing of water pipes (wherever needed). In addition, the utility replaced spaghetti water connections with a new tertiary distribution network and house connections with functional meters; added supply lines to prioritise the development of slum areas; installed valves and water meters to isolate hydraulic zones and allow supply and consumption to be measured at both ends; initiated timely measurement related to non-revenue water (NRW) to keep it below 15 per cent in each DMA; and used supervisory control and data acquisition (SCADA) systems, pressure-retaining valves, pressure sustaining valves, and data loggers for efficient network management.

The DMA approach delivered quick results for customers, and made it easier for the utility to revamp the system. DMAs are permanent systems, which make for better day-to-day operations and management. NRW loss was reduced significantly from more than 40-50 per cent to less than 15 per cent (as targeted) and to even as low as 1.58 per cent in some areas. The other noteworthy benefits of the DMA approach were:

  • Continuous supply of water to all households through a pressurised system.
  • Regularisation of illegal house connections.
  • Assurance of potable water.
  • Usage of suction pumps was discontinued and deep tube wells were replaced and regenerated for source development.
  • Reduced electricity cost for DWASA as well as for consumers.

In order to make the project’s construction work feasible, trenchless technology was used for laying pipes. Horizontal directional drilling machines, a type of trenchless technology most suitable for small-diameter water supply pipes, eliminated the need for expensive relocation and reconstruction along sidewalks and easements. Further, chlorination facilities were set up at all supply points including groundwater pumping stations to improve the water quality.

The way forward

The project was completed in June 2016. About 8 million people benefited from 24×7 water supply, good pressure at the consumers, end and good quality of potable water. The project included pipe rehabilitation works carried out based on the DMA approach for substantial reduction in NRW and used the saved water to improve the service level to 24 hours.

DWASA has adopted an aggressive growth path. In view of the success of the Dhaka Water Supply Sector Development Program, DWASA has initiated the Dhaka Environmentally Sustainable Water Supply Project. Approved in October 2013, the project will provide a new surface water supply scheme, including new surface water intake, transmission mains, a water treatment plant, networks and household connections. It will reduce the groundwater abstraction by 150 million litres per day. The project is scheduled to be completed by 2020. Another project that has been initiated by DWASA is the Dhaka Water Supply Network Improvement Project. Approved in June 2016, it is expected to be completed by 2021. The project aims to cover 6.5 million people living in those areas of the city that are not yet covered by the two investment projects.

Going forward, DWASA has set an example for other utilities facing water-related problems. The successful implementation of the Water Supply Sector Development Program and the transformation of a dysfunctional utility into one of South Asia’s leading public utilities will serve as an example for other water utilities, encouraging them to implement similar initiatives in their cities.

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