The classic example of NRW management in India is the Bengaluru water loss management project which was initiated by the Bangalore Water Supply and Sewerage Board (BWSSB). The project was funded by the Japan International Cooperation Agency (JICA) and was awarded to SPML Infra Limited in consortium with Suez. At the time of project award, the NRW level in the designated area was over 61 per cent. In a busy city like Bengaluru, executing a water loss management project in the central part was an engineering challenge due to very high traffic volumes combined with narrow streets of densely populated areas and business hubs. The project area also included areas with the maximum number of slums, which posed a tough challenge to bringing down the water loss from the existing levels to optimum levels. With strategic planning and dedication of the team, the project has already covered major areas where 50-60-year-old pipes have been replaced with new pipes, leakages have been sealed, and electronic district meters suitable for global system for mobile communication/ general packet radio service communication have been installed for measuring flow and pressure control.
By using innovative helium leak detection technology to accurately identify and locate hidden leaks in large and small pipes, NRW reduced significantly from 61 per cent at the beginning of the project to 27 per cent currently, thus saving 39.2 million litres of drinking water per day. The water saved from the project will be used to provide drinking water facilities to 110 urban settlements for which the creation of water networks is under progress in the extended colonies of Bengaluru city. Reducing water losses due to leakage has been the focus and the action taken has resulted in significant improvements. The water loss management work is still in progress and has a target to reduce the NRW rate further to an optimum level of 15-18 per cent. Once this is achieved, it will save another few million litres of drinking water every day.
IT initiatives under the project
Information technology (IT) has played a crucial role at every phase of project execution. A phase-wise elaboration of the above and its link with IT is given below.
- Digitisation of the water network: The design phase involves studying the existing network and digitising it using GIS software. The pipe details and specifications recorded by the software is further used for design and engineering. After digitising the existing network, it was imported into design software WaterGEMS for analysis. The data was then transferred to drawing software AutoCAD for reference and execution.
- Design of the network: Once the existing network is developed on a GIS software platform it is imported and analysed using InDesign software for the final outcome of the improved distribution system.
- SCADA integration and UFW calculation: With the formation of district metering areas (DMAs), inlets and outlets of the DMAs are installed with electromagnetic flow meters for accounting net inflow to the area. The net inflow to the area is compared with the sum of the billed volume and unbilled accounted volume and the difference between the net inflow volume and the accounted volume is termed as unaccounted-for water (UFW). To calculate the UFW for 43 DMAs, all the inlet and outlet flow meters are integrated with a SCADA system through GSM-based communication technology which assesses net inflow to the DMA. Accessing all the flow meter data from a single location through SCADA helps in the calculation of the net inflow for each DMA with ease. Separately, the consumption volume calculated from BWSSB’s billing and collection system is fed separately for the calculation of UFW.