Urban water supply systems are constantly reeling under the stress of supplying adequate, reliable and safe drinking water. Some of the major issues to be addressed to meet consumer demand in an urban system are equitable supply of water at different levels, leakage minimisation, pressure and asset management, developing better water supply infrastructure, managing groundwater pumping, etc.
O&M and asset management
Operations and maintenance (O&M) and asset management practices are becoming an important aspect of managing water resources as clean and reliable water is a resource that will play a vital role in the 21st century. Best practices in O&M and asset management of water resources include reducing non-revenue water (NRW), ensuring adoption of smart solutions, design improvements, comprehensive assessment, and efficient collation of data to promote better operations.
In order to yield results, it is imperative that asset digitalisation and systematic record of maintenance activities are implemented to improve data quality. Development of smart meters has been acting as the key driver of more efficient and intelligent solutions being adopted in water management. Digital operations will help improve the understanding and better utilisation of the capacity of the water system. Further, miniaturisation with 24-hour telemetry of sensor equipment is another important advancement that will promote transparency and ensure better monitoring of water quality.
NRW reduction and leak detection
Reduction of NRW is one of the key methods to ensure continuous and equitable supply of water in cities. To provide 100 per cent water supply to all customers in Metro Manila, Manila Water ensured that they reduced water losses to a minimum. It brought the NRW down to 13 per cent in 2020 from 63 per cent in 1997. Strategies to reduce NRW include encouraging employees to provide ground-level business solutions, facility improvement, capacity building, and deploying proactive technical solutions such as network modelling, meter maintenance, pipe rehabilitation and replacement, leakage detection, data system management and active leakage control, and pressure management. The key challenges to reducing NRW include employees’ readiness, organisational constraints, high network losses and lack of customer support.
Leak detection is an important aspect of managing NRW levels. If the issue of water leakage is addressed efficiently, it will enable efficient water consumption. SUEZ uses a leak detection system, Idorloc, in which helium is used as a tracer gas.
Initiatives by local governments
In Bengaluru, India, the Bangalore Water Supply and Sewerage Board (BWSSB) is responsible for water supply and sewage disposal in Bengaluru city. BWSSB has taken appropriate steps such as rainwater harvesting, reusing wastewater and reducing NRW and leakages to ensure judicious use of the present freshwater resources. The utility has successfully reduced NRW from 42 per cent in 2012 to 35 per cent in 2020. It aims to bring this down to 30 per cent by 2030. It has also undertaken various information technology initiatives such as providing online water connections, launching Sajala, a web-based billing application, centralised supervisory control and data acquisition (SCADA) monitoring centre and vehicle tracking system, and a real-time online water quality monitoring station.
In a bid to improve the water system in Phnom Penh, the Phnom Penh Water Supply Authority (PPWSA) undertook various initiatives such as routine management, leak control programmes, district metering area (DMA) programmes, adopting technological advancements and working on improving the city’s water infrastructure. As a result, it was able to reduce NRW levels to 8 per cent in 2018 (from 72 per cent in 1993).
24×7 water supply and advanced pressure management system
Pressure management is becoming a key factor in 24×7 water supply systems as it facilitates reduction in leakages and ensures efficient water consumption. There is also a growing need to establish stable water supply networks as fluctuations in water pressure adversely affect the strength of pipes and lead to their premature ageing. Installing pressure reducing valves is the most common method of controlling water pressure in a particular area. Over the past 10 years or so, advanced modulation has gained traction in the water pressure management sector. Through advanced modulation devices, data regarding flow of water is uploaded on a cloud server and is collated on a daily basis.
In India, a 24×7 water supply project is being implemented in Nagpur, Maharashtra, by Orange City Water Limited (OCWL). The project succeeded by deploying strategies such as 24×7 water supply trials in the first stage, implementing an initial performance improvement programme, use of advanced technology and methodology, incorporating an asset rehabilitation plan, DMA and sub-zone formation, identifying and resolving water pressure issues, resolving contamination issues, preparing strong ground-level management and ensuring equitable distribution of water. The technological and methodological advancements deployed under the project include SCADA, geographic information system, and an in-house developed tank cleaning system. Further, it has improved asset management and the complaint redressal system and ensured that water is distributed equitably across the city.
In a bid to improve customer service and expand the water supply network, private sector participation in the water supply sector has been increasing over the past few years. SUEZ is one private player that has ventured into the water supply sector and has a presence in five continents. The company has been providing water supply services in India for over 40 years. SUEZ India has worked on various projects in cities like Delhi, Coimbatore, Davanagere, Bengaluru, Mangaluru, Udupi and Puttur.
Private players add value in a water supply project by improving operational efficiency, delivering superior service and ensuring better customer satisfaction. They also bring in efficient and better management practices along with the much-needed capital investments. To get better results from a public-private partnership (PPP), contracts with performance-based incentives and penalty criteria must be promoted as they create a good balance between infrastructure and O&M in projects.
Overexploitation of groundwater, heavy NRW losses and limited reuse and recycling of wastewater are the root causes for the precarious tilt in the water balance. It is essential to cover the whole water cycle, from collection to discharge, together with water network and customer management, to meet the increasing water needs of cities. Going forward, it is imperative that both public and private players and other stakeholders work together and manage water supply systems efficiently, sustainably and equitably. n
Based on discussions at a recent India Infrastructure conference with Nicolas Bockhoff, Chief Operating Officer (CEO), SUEZ; Rajiv K.N., Additional Chief Engineer, BWSSB; Sanjoy Roy, CEO, OCWL; Matthew Diserio, President, Water Asset Management, LLP; Joemar B. Emboltorio, Head of Water Supply Operations, Manila Water; Rey-Ann Dela Cruz, Head, Operations Planning, Manila Water; Gary Wyeth, Senior Consultant, Isle Utilities; Marco Fantozzi, Managing Director, Isle Utilities; Derek Atkinson, Senior Consultant, Isle Utilities; Sheila Kee, Senior Product Manager, Water Operations Management, Itron; Pheng T.Y., Director, PPWSA; and Wiljeim B. Laureola, Senior Manager, Central Non-revenue Water Management Division, Maynilad Water.