The Impact Of Application Of GIS Technology On Non-Revenue Water Levels: A Case Study Of Narok Water And Sewerage Services Company.

Abstract

Non-Revenue Water (NRW) is the water loss that does not earn income/revenue to a Water Service Provider(s) and is lost through physical losses for example leakages/burst in the distribution system or commercially through water theft, malfunctioned water meters, and many others. NRW has been treated as a very serious issue in Kenya, and it is one of the key performance indicator used by Water Service Regulatory Board (WASREB) to rank the performance of the Kenya Water Service Providers. Geographic Information System (GIS) technology provides many powerful tools that allow integration of many types of data (Raster and Vector) and also analyses spatial locations. Narok Water and Sewerage Services Company (NARWASSCO) adopted the use of GIS technology in the year 2015 for mapping of its distribution network which has really aided in management of NRW in the company hence there was a need for assessment of the impact of the technology on NRW management in relation to the NRW levels (Percentage water lost) to help in decision making. A well-defined small area called District Metered Area (DMA) was chosen, then the quantifiable NRW management activities were identified from when the District Metered Area, was formed as well as the NRW levels. The changes were then assessed using a standard deviation calculated using Statistical Package for the Social Sciences (SPSS). The standard deviations were used to assess the intensity of change in NRW management activities and NRW levels for years 2013 to 2018 in relation to the improvement made on these activities after GIS implementations. The standard deviations were then used to show the impact of GIS technology on NRW levels taking into consideration any other factors of which, according to this study, it was mainly the number of connections (coverage). The identified NRW management activities were considered to affect the NRW levels differently; hence, the standard deviation for each was interpreted differently, which gave either positive or negative standard deviation. It was found that there was a significant standard deviation in NRW levels after implementation of GIS as compared to before, which depicted a high impact of the technology. The NRW reduced from 56% in 2013 to 25% in 2018, which is an acceptable level. It was also the same with all NRW management activities, which showed a positive standard deviation in relation to NRW levels. It can, therefore, be concluded that GIS technology has brought about a significant impact on the management of NRW in NARWASSCO and has made the NRW management easy and cost-effective in that most of the things can now be done in-office by anyone without even going to the field. It is therefore critical for any Water Service Provider(s) to adopt the GIS technology to help in the management of NRW to an acceptable level set by WASREB of 25%.