This file contains three main documents: a preliminary study, extensive research with data, as well as an analysis of the emissions to the water of Brussels, particularly the Senne and the Canal. The data has been collected between 2011-2013, but is in my understanding the most recent study on the issue. You can find a summary on this link: https://www.environment.brussels/state-environment/report-2011-2014/water-and-aquatic-environment/chemical-quality-surface-water