Low-Cost Flow Sensors: Making Smart Water Monitoring Technology Affordable

High-quality water-related data are fundamental to water-resource planning, water and sanitation infrastructure design, and scientific research. However, high-resolution smart water-monitoring equipment can be extremely costly and vulnerable to vandalism and theft. Consequently, developing countries struggle to acquire and maintain high-quality monitoring instruments. Thus, water data in those countries remain fragmented, inaccurate, and largely based on isolated measurements. This article describes a smart low-cost remote-monitoring flow sensor designed for the developing country context. The sensor uses low-cost off-the-shelf sonar devices to gauge river height as a proxy for flow rates and operates via an Internet-of-Things (IoT) node based on the Global System for Mobile Communications (GSM) standard. The sensor transmits logging data to a centralized server to provide realtime data analytics.