One of the most challenging problems faced by water utilities across the globe is the high level of non-revenue water (NRW). The NRW levels in Southeast Asia are among the highest in the world. The average NRW level in India is over 40 per cent. The loss of water in the distribution process is largely attributed to physical losses such as leakage and theft. To tackle these problems, water utilities are constantly developing and adopting new technologies and are successfully reducing the NRW levels at a steady pace.
The operational efficiency of water distribution systems has improved over time with the division of the network area into smaller district metered areas (DMAs). Water utilities are now using technologies such as flow meters and pressure monitors to detect leakages or other unusual activities in the water distribution system. The implementation of real-time monitoring and data analysis through database systems has resulted in the quicker detection and resolution of problems. Technologies such as supervisory control and data acquisition (SCADA), internet of things (IoT) and geographic information system (GIS) are also enabling the development of the sector.
Technology initiatives by major cities
Metro Manila, the Philippines
Maynilad is the largest water utility in the Philippines. It provides water and wastewater services in the west zone of Metro Manila, covering 17 cities and municipalities with a total population of over 9 million customers and 1.5 million water connections.
In 2007, the situation in the west zone of Metro Manila got worse with high levels of NRW. Around 1,500 million litres per day (mld) of water loss (almost 66 per cent) was reported. Of this, about 75 per cent was due to physical losses such as leakage and ageing of pipes. Only 50 per cent of customers were getting good quality water supply, while 3 million people lacked access to piped water.
To reduce the NRW levels in the distribution system, Maynilad implemented various strategies as part of its NRW reduction programme. These included water auditing, DMA establishment, active leakage control, integrated meter management, selective pipe replacement, pressure management, hydraulic modelling and data management.
The network area of Metro Manila was divided into 1,600 DMAs, each having 500-2,000 connections. Instruments and technologies such as portable on-site meter testers, NRW data management systems and automated data transmission systems were introduced, which helped in faster recording and communication of data. Manual processes such as data analysis and meter reading were automated, which resulted in quicker and more accurate results. Leakage detection equipment was also developed by the utility to find and pinpoint leakages in the water distribution system.
All these technological advancements have not only helped in the reduction of NRW levels, but have also increased the operational efficiency. The NRW level in Metro Manila has dropped from 66 per cent in 2007 to 32 per cent in 2021. The utility has provided water to 3 million more households by reducing the NRW levels by 50 per cent. This programme has been a huge success due to technological advancements. It has helped improve the utility’s services and people’s access to piped water supply.
In 2014, the situation of unaccounted for water (UFW) in Bengaluru was poor. The city recorded a UFW level of 61 per cent. In view of this, SPML India Limited started the UFW and Leakage Control Project for the Central Division, Bengaluru, in a joint venture with Suez Environment, which was completed in 2017. The project aimed at the development and improvement of existing infrastructure facilities to reduce UFW. It covered an area of 26.5 square km with a network length of 756 km. It had a total of 89,159 connections with 15 service stations.
The pipeline network was 40-60 years old and was established in a densely populated business area with heavy traffic and narrow roads, which made it difficult to carry out digging and construction works. The network had 5,920 unauthorised connections and abnormalities in 870 meters.
To kick off the project, SPML India conducted asset surveys, topographic surveys and house-to-house surveys. The asset, connections and historic leaks information was then uploaded to the GIS. SPML India also conducted a study on DMA designs and network models.
The main instruments installed in this project were flow meters, pressure monitoring sensors and ultrasonic water level indicators. Flow meters were installed in the pipeline network and recorded the volume of water inflow and outflow, thereby checking for leaks and illegal connections. The helium leak detection technique was also used on an annual basis to check for leaks and breakages in pipes, which helped in pinpointing leak points and eased the maintenance process.
The SCADA system was synchronised to monitor the project. A total of 43 DMAs were established across three divisions and six subdivisions. SPML India also installed 113 district meters and laid 121.3 km of ductile iron pipeline and 10.4 km of mild steel pipeline. Further, 20,752 house service connections and 22,833 consumer water meters were replaced while 14,129 visible leaks and 1,811 invisible leaks were repaired during the tenure of the project.
UFW in Bengaluru dropped from 61 per cent in 2014 to 52.78 per cent in March 2017. In January 2022, the UFW level stood at 20.83 per cent. These techniques have helped save 47.36 mld of clean water amounting to Rs 0.73 billion per annum.
Technological advancements have reduced NRW levels, and operations and management costs, as well as improved the water quality. The implementation of these technologies also poses challenges. For instance, to reduce the physical water loss, the existing infrastructure needs to be repaired, which is a tedious task in densely populated countries such as India. Additionally, due to the mindset of the general public regarding free or subsidised use of water, there is not much revenue generation in the water sector, which leads to difficulties in the development of large-scale projects. To overcome this, the government needs to launch programmes and schemes to promote healthier use of resources and discourage wastage. Moreover, it needs to focus on revenue generation, and the development and adoption of newer technologies.
Based on presentations by Vishvewaraiah, Vice President (Projects), SPML Infra Limited, and Eng David Andrew B. Fernandez, NRW Manager, NRW Services, CNRW Division, Maynilad Water Services, Inc., at a recent India Infrastructure conference