RESEARCH Open Access A system for monitoring water quality in a large aquatic area using wireless sensor network technology Alexander T. Demetillo 1,2* , Michelle V. Japitana 1,2 and Evelyn B. Taboada 1 Abstract In this paper, a low cost, real-time water quality monitoring system which can be applied in remote rivers, lakes, coastal areas and other water bodies is presented. The main hardware of the system consists of off-the-shelf electrochemical sensors, a microcontroller, a wireless communication system and the customized buoy. It detects water temperature, dissolved oxygen and pH in a pre-programmed time interval. The developed prototype disseminates the gathered information in graphical and tabular formats through a customized web-based portal and preregistered mobile phones to better serve relevant end-users. To check the system effectivity, the buoy’s stability in harsh environmental conditions, system energy consumption, data transmission efficiency and web- based display of information were carefully evaluated. The experimental results prove that the system has great prospect and can be practically used for environmental monitoring by providing stakeholders with relevant and timely information for sound decision making. Keywords: Dissolved oxygen, Environmental management, pH, Water quality monitoring, Wireless sensor network Introduction Nowadays, water is considered as one of the most scarce natural resources on our planet [1]. It is important to humankind, animals, and plants [2]. Depending on the quality of water, it may either be a source of life and good health or a source of diseases and deaths. The growing environmental degradation in recent years brought about by development, population increase and climate change increases the need for researchers to look into its negative impact in the environment, espe- cially in water sources and its implication. Increasing water pollution in oceans, lake, and river triggers world- wide demand more advanced methods in environmental monitoring systems particularly in the field of water quality monitoring. Moreover, developing countries like the Philippines rely on the conventional methods of col- lecting water samples and water analysis. Due to lack of technical know-how and a huge amount in the initial investment, water analyses are usually done through conventional procedures or by using portable testers which are not only expensive and laborious but also lack the capabilities for real-time data acquisition, analyses and fast dissemination of gathered information which are crucial and essentials for effective water quality monitoring endeavour. This Wireless Sensor Network (WSN) is suitable for monitoring physical and chemical water characteristics in remote areas at lower cost and reduce manpower requirement [3]. It can be utilized for water quality mon- itoring [4] which presents many advantages like its por- tability [5] and near real-time data acquisition and data logging capability [6]. It has gained popularity among the research community ranging from environmentalist [7] to embedded systems community [8]. However, WSN applications for the aquatic area are far more challenging activities compared to the land-based WSN applications [9] due to its electronic component which has zero tolerance to water or even moisture intrusion. WSN-based applications for environmental moni- toring have been implemented for applications such as water quality monitoring [4, 10–12], water chemical monitoring [8], hydrodynamic performance monitoring © The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. * Correspondence: atdemetillo@gmail.com 1 School of Engineering, University of San Carlos, Cebu City 6000, Philippines 2 College of Engineering and Information Technology, Caraga State University, Butuan City 8600, Philippines Sustainable Environment Research Demetillo et al. Sustainable Environment Research (2019) 29:12 https://doi.org/10.1186/s42834-019-0009-4