Tracking Soil Saturation in Earthen Embankments Using a Network of Wireless Conductivity Sensors

Abstract

Expansive clay embankments along transportation corridors are vulnerable to moisturedriven shrink-swell cycles that threaten their structural integrity. This work presents a low-cost, solar-powered, wireless sensor network designed to monitor soil moisture in real-time using electrical conductivity as a proxy. Five custom-built sensors, deployed 10 cm below the surface, record conductivity, temperature, humidity, and barometric pressure, transmitting data to a solar-powered base station that syncs with a cloud server for remote access. Field testing over seven days validated the system’s durability, communication reliability, and power sustainability under variable weather conditions. Spatial moisture maps generated using spatial interpolation demonstrated the system’s utility in identifying zones of elevated saturation. This open-source system represents a scalable tool for continuous monitoring of earthen embankments to support early warning and risk mitigation efforts.