The Bangalore Water Supply and Sewerage Board (BWSSB) is responsible for the planning, management and provision of water and sewerage services in the Bengaluru metropolitan area. Currently, BWSSB has 800 square km under its jurisdiction and supplies 1,280 million litres per day of water to the city. With the steady urbanisation and rapid expansion of the city periphery, the demand for water supply and sewerage management services has increased significantly. To manage, rehabilitate and expand its asset base, BWSSB has implemented a geographic information system (GIS). GIS acts as a decision-making tool by creating a network of information by mapping the utility’s assets.
Need for GIS
A planned asset management system is imperative for maximising the productivity of utility assets. This requires a sound understanding of the current condition and performance of the assets, optimal utilisation of the assets, and minimising the expenditure and long-term investment needs of the utility. Therefore, it is essential to maintain accurate data sets of the assets.
The use of GIS minimises the time spent on the production of physical network maps. The system provides timely and updated information regarding the assets, which is essential for the analysis and implementation of optimum solutions. The technology assists in capacity evaluation and required refurbishment in a time-bound manner. Current information is made accessible across all offices and internal departments, thus improving coordination among them. The system promotes smooth operations and easy maintenance of vital records, thereby reducing operational costs and enhancing the efficiency of BWSSB. A comprehensive GIS enables database mapping to improve project planning and financial management for water and sewerage networks.
BWSSB developed a comprehensive GIS and implemented computerised utility mapping in two phases between 2000 and 2002. Under Phase I, 100 square km area was taken in its purview and in Phase II, 190 square km of area was covered. The approximate cost of the project was Rs 100 million and it was financed under the Indo-French protocol. GIS consisted of mapping various assets of BWSSB, which included the digitisation of buildings, roads, green areas, reservoirs, water-bodies, water and sewer pipelines, valves, manholes, fire hydrants, consumer connections, etc. Further, this computerised asset information was distributed at four levels – Bruhat Bengaluru Mahanagara Palike limits, division limits, subdivision limits and service station limits.
At present, under this system, BWSSB has obtained the base map for an 800 square km area of the city from the Bangalore Development Authority. The network database is regularly maintained and updated by the Network Information Centre, a Government of India undertaking. The software used in the GIS includes Arc Map 10 for the front end, Oracle 10g for the back end and Arc SDE 10 for the connector. BWSSB has three GIS layers, which comprise point features, polygon features and line features. The point features include information on various parameters like annotations, borewells, consumers, fire hydrants, offices, manholes, pumping stations, reservoirs and valves. The polygon features include information on wards, buildings, green areas, divisions, subdivisions and service stations. The line features cover parameters like drain axes, sewer lines, water bodylines, water pipes and roads. The GIS scheme in BWSSB consists of a digitised database of water lines, sewer lines, valves and manholes.
GIS is not only useful in the compilation of a database but also gives a segment-wise analysis of utilities. It enables the scrutiny of the water supply and sewer line network on a service-station/subdivision/division basis. The water supply and sewer lines can also be examined across different parameters like diameter, age and material. This technology has also enabled the identification of consumers and the location of areas prone to frequent complaints.
The deployment of GIS in BWSSB met with various challenges. For instance, before the implementation of GIS, the integrated base map was not available. For some places, the base maps were available but were in blueprints and of different scales. Therefore, obtaining a single base map of the entire city in a 1:1,000 scale with the required coordinates was one of the biggest challenges. To overcome this problem, BWSSB employed the National Remote Sensing Agency for aerial photography of 1,200 square km of the city area and further digitised it. For this, BWSSB had to obtain clearances from the Ministry of Defence.
Moreover, the ground data collected and digitised to GIS base maps did not match the actual characteristics of the assets like the make of pipes and their diameter. However, GIS maps with correct attributes have been refined over a period. As of 2007, 50 per cent of the asset data was accurate and updated in GIS. Later, from 2007 to 2014, the data accuracy reached 75 per cent. In the next decade, 90 per cent accurate data will be updated in GIS. Apart from data accuracy, BWSSB is also facing issues related to accessing data remotely and validating ground data vis-à-vis water supply and sewer assets. Another issue is the limited availability of trained and capable personnel for the maintenance and management of GIS.
BWSSB plans to implement web hosting of GIS data through the intranet and internet. Larsen & Toubro undertook the project and implemented Web GIS. The scheme will allow the staff to view the spatial data. This will also enable users to view updated data across the organisation in real time. The system is beneficial for network restoration, fixing visible leaks, isolating valves, hydrant rehabilitation and remedial pipe work. The creation of a centralised Web GIS database will lead to success in every work related to spatial analysis.
In the near future, BWSSB is planning to integrate Web GIS with the complaint management system, water quality check and the revenue billing system. The incorporation of Web GIS with the complaint management system will help in the quick identification of complaint location, and status and nature of complaints for any given period and area. The system design will meet the need for the analysis of complaint registration and repairs. This will further help in the speedy implementation and verification of corrective actions to address grievances. In the water quality checking system, data pertaining to water samples will be maintained in GIS for the analysis of the city’s affected zones. GIS linking with revenue billing data will integrate consumer data with GIS to analyse the supply/ demand requirements, and enable BWSSB to bridge the gap. The board is also looking forward to the incorporation of the global positioning system with hand-held devices for improved data collection.
Besides, the board has installed 500 automated meter reading (AMR) consumer meters for the identification of consumer details and 250 ultrasonic bulk flow meters for accounting purposes. These meters are operated on GSM and GPRS technologies. To keep track of water usage, the data is transferred to the server every hour. In the case of AMR meters, every day one reading is recorded every day in the server and transferred to the billing section. The bill is generated automatically and sent to the consumer. BWSSB is planning to integrate this particular technology with Web GIS in the near future.
BWSSB has been at the forefront of deploying GIS technology for mapping utility assets. It is the first water utility to receive the Special Achievement Award from ESRI for the implementation of GIS. Although, various initiatives are currently in the implementation stage, BWSSB is expected to reap the benefits of this technology. In the long run, the application of GIS by the BWSSB in urban utility planning and management will prove to be a valuable step. It will be helpful not only in the day-to-day management of utilities, but also in planning future infrastructure. The scheme is expected to increase BWSSB’s efficiency and improve its service delivery. Further, it will be an example for other urban agencies in the country to learn from and replicate.
Based on a presentation by V.B. Maheswarappa, Assistant Executive Engineer, Water Audit, Network Planning & Design, BWSSB, at an India Infrastructure conference