In 1993, Cambodia was rebuilding after the civil war. The water situation across the country was abysmal with almost no drinking water available. The shortage in the capital, Phnom Penh, was also severe. The city had a network spanning 288 km for water supply with old and unrepaired pipes. The water supply coverage was only 20 per cent in the capital region and the supply duration was 8-10 hours per day with a supply pressure of 0.2 bars. These problems were due to electricity issues, resulting in subsequent water pumping problems. The number of illegal connections across the city was on the rise due to the shortage of water supply. Citizens were able to break the pipes easily. To address this, the water supply authority of Phnom Penh implemented various initiatives for water network management at the time.
Master plans
With assistance from various international agencies such as the Japan International Cooperation Agency, the World Bank and the Asian Development Bank, the Phnom Penh Water Supply Authority (PPWSA) developed various master plans for the improvement of the water network in the city. These master plans were formulated with the aim of achieving the sustainable development goal (ensuring access to water and sanitation for all). The first master plan was formulated for the period 1993-2010, while the second was for 2005-20. A need was felt for a new master plan, the third plan, which was formulated for the period from 2015-16 till 2030. It aims to improve urban water supply and distribution, develop a new tariff system and build climate resilience.
One of the major initiatives in the latest master plan is the development of Cambodia’s largest water treatment plant (WTP). The Bakheng water supply project is the major infrastructure project defined in PPWSA’s third master plan. The Bakheng’s water production facilities are expected to increase the water production capacity in Phnom Penh by 65 per cent, from 600,000 cubic metres per day at present to around 1,000,000 cubic metres per day by 2024. As of April 2022, around 60 per cent of the construction work of the WTP has been completed. The first phase of the project with a capacity of 195,000 cubic metres per day will be put in operation in the first quarter of 2023, and the full capacity will be reached one year later after the completion of Phase II.
In addition, PPWSA will expand the transmission network by 130 km and the distribution network by 1,600 km throughout the city. It will be able to serve an additional 100,000 domestic connections and 25,000 commercial connections and improve the service quality for all citizens. PPWSA aims to maintain its water supply coverage and expand its service area to 100 per cent of the city by 2025, with support from the French Development Agency, the European Investment Bank and the European Union.
NRW reduction programme
As of 2021, service connections in the city stand at over 430,000 while the pipeline network is around 3,850 km. PPWSA is now focusing on the reduction of non-revenue water (NRW). Managing the water loss has been the most critical function of PPWSA’s operations because a decrease in water loss results in an increase in billing and income. In 1993, the rate of water loss experienced by PPWSA was 72 per cent. This rate decreased to approximately 9.7 per cent in 2021.
Before 1993, customer management was highly inefficient. The number of customers appearing in PPWSA’s records was different from the actual number of customers. Furthermore, the records did not have details of people with water connections, but contained details of people with no water connections. These factors resulted in a bill collection rate of only 48 per cent. In order to correct its records, PPWSA along with the Phnom Penh Municipality carried out data collection from March 1994 till late 1994. As a result, over 13,000 water connections were identified, whose names did not previously appear in PPWSA’s records. In total, 1,945 collective wells were identified for which no water bills were being paid. At the time, due to the low water pressure of the supply system, people used to dig wells and pierce main water distribution pipelines to cause water to flow from the pipelines into the wells. In order to overcome these issues, PPWSA came up with solutions like installing meters on the pipelines that were used to provide water to the wells. These collective wells no longer exist, as water connections have been installed in each household.
Another solution adopted in order to reduce NRW in the city was the metering of all household connections. PPWSA also introduced a monitoring and replacement programme. In 1993, 12.61 per cent of all water connections had water meters, resulting in most water bills being calculated based on assumptions. In 1994, PPWSA commenced the installation of water meters in all household connections and ceased calculating water bills based on assumptions. In order to improve the accuracy of water meters, PPWSA, in 1997, started replacing old meters which had low accuracy and a bias rate of more than 8 per cent with new meters, which had higher accuracy and a bias rate of around 2 per cent.
Another measure in the management of water meters was a programme for monitoring the replacement of meters. The longer the meters were in service, the higher their bias rate was. In 1994, PPWSA established expert offices to regularly monitor and replace meters as per the standard operating procedures.
PPWSA took various other measures for reducing NRW in the city including effective leak repairs, standardised design of last-mile service connections, district metering area programme, introduction of internal service contracts, and setting up of a water loss control committee.
In sum
PPWSA is committed to the sustainable development of water supply services as well as management of Phnom Penh city. It also aims to provide services in other cities and provinces of Cambodia, ensuring access to potable water for all. Despite various challenges such as water levels going down over the past five years, higher electricity rates for raw water pumping, damage to transmission and distribution pipes, and asset management issues, PPWSA has transformed the water network in the city. It has also undertaken various technological interventions in the recent past such as deployment of a supervisory control and data acquisition system, transmitters and sensors, central servers, etc. n
Based on a presentation by H.E Long Naro, Director, General, Phnom Penh Water Supply Authority, Cambodia, at a recent India Infrastructure conference