Abstract

SALDARRIAGA, Juan G. et al. Location of Water Quality Monitoring Points in Distribution Systems. Tecnol. cienc. agua [online]. 2014, vol.5, n.2, pp.39-53. ISSN 2007-2422.

Companies providing drinking water services in developing countries have been using empirical procedures for years to locate points in distribution networks at which periodic sampling should be taken in order to ensure compliance with minimum water quality standards. Although these companies have excellent information tools to model the water dynamics and evolution of water quality in networks, not enough data exists to scientifically choose these points. Additionally, the coefficients for bulk and wall chlorine decay are not known. Despite this limitation, several methodologies have been developed and implemented to design sensor networks that ensure continuous monitoring of water quality in distribution systems, but that also involve a high degree of uncertainty. The study herein was to develop a methodology to choose water quality monitoring points in an environment with little data. This would simultaneously address two typical problems of distribution networks-ensure water quality by measuring residual chlorine using a software developed for this study, and detect water coloring problems (in which the water reaching a set of users is not transparent, affecting the users' perception of its quality) due to the detachment of biofilms using the TEVA-SPOT program (Berry et al., 2008). The latter approach can be developed by optimizing multi-objective functions according to the type of protection against coloration events desired. The new methodology was successfully applied in the 37 hydraulic sectors into which the drinking water network in the city of Bogota, Colombia is divided (approximately 8 million inhabitants). Lastly, although the study was performed in 37 sectors, one of these sectors was used as a prototype of the network for the purpose of this study. The results show that both methodologies are reliable and the design of sensor networks depends on the objective to be optimized.

Keywords : early warning sensors; monitoring; drinking water distribution networks; water quality.