Towards Underwater Detection of Diluted Bitumen with Interdigital Sensors

Diluted bitumen spills in freshwater environments pose significant challenges for detection and remediation due to the complex behaviour of the material once released, rendering traditional oil monitoring techniques, such as aerial surveys and fluorometry, ineffective. This study investigates the feasibility of utilizing interdigital capacitive sensors to detect dilbit in water via frequency-dependent impedance measurements. Three sensor designs were fabricated and tested with a vector network analyzer across samples with varying dilbit concentrations. All capacitor designs were able to detect electrical changes in water and exhibited different linear regions, suggesting a strong potential for quantitative sensing. These findings support the integration of the sensors into autonomous underwater robotic platforms for real-time, distributed monitoring of dilbit spills in freshwater systems.