A black tide at the outlet of the canal Agnena (Caserta, Italy) was spotted along the coasts of the Tyrrhenian Sea. It happened on the 4th of May 2020, a date that corresponds to the restart of some industrial activities, as some of the COVID-19 restrictions are being lifted in Italy. While the likely-illegal discharge is under investigation, the pictures of the event reported by the media are being questioned, as these represent a dark patch much larger than what assessed by the authorities.

Picture of canal Agnena outlet as reported by media

To shed some light on this phenomenon, ColomboSky’s team had a go on investigating whether satellites could help out. In fact, by means of satellite detection methodologies, ColomboSky is able to identify and track marine pollution and is at the forefront of environmental monitoring in the Mediterranean Sea.

We tested the coastal area reported to be affected by the black tide event by analysing satellite data acquired by the ESA Sentinel missions, part of the Copernicus programme. Time series of multispectral optical or Synthetic Aperture Radar (SAR) data cover large regions and are available with low latency after the event. The resulting images confirmed the discharge of pollutants at the outlet of the canal and provided useful insights into the nature of the phenomenon.

High resolution Sentinel 2 images
By using our satellite technology combined with detection algorithms and machine learning, the competent authorities could assess with high precision the extension of the phenomenon, monitoring its expansion over time.  Moreover, thanks to the application of proprietary ocean circulation models ColomboSky can forecast the diffusion of pollutants at sea, providing a powerful tool to effectively target cleanup and pollution mitigation efforts. A special alerting system would raise a timely warning to inform competent authorities about the environmental risk.