Innovative forecasting approaches to assess future trends in pollutant flows from land to water systems for advancing sectoral water quality service

Research introduction

Multiple pollutants contribute to the decrease of water quality in surface waters: rivers, lakes, and reservoirs. Multi-pollutant contamination of surface waters is a global issue. Global change including socio-economic developments and climate change may influence water quality in the future. As a result, the availability of clean water for sectors such as agriculture and domestic use may decrease. Nutrients, chemicals, plastics, and emerging pollutants (e.g., pharmaceuticals) are examples of contaminants found in high concentration levels in water systems. These pollutants have multiple impacts on several sectors (e.g., domestic, agricultural, recreation, and nature), resulting in a decrease of the clean water availability. Moreover, multiple pollutants in water often originate from common sources such as agriculture and urbanisation.

Research challenges

So far, existing modelling approaches mainly focus on individual pollutants. The main research objective of this study is therefore to assess trends in flows of multiple pollutants from land-based sectors to water systems, and to explore effective measures to achieve clean water for multiple sectors in the future at the sub-basin scale worldwide. This research will start from existing models, integrating new pollutants and new sources. I will use innovative forecasting multi-pollutant approaches that I will develop based on the existing MARINA-Global model to evaluate river export of multiple pollutants at the river mouth. To fill the gaps found in the standard water quality modelling approaches, I will address the common origin of multiple pollutants and study their multiple impacts, accounting for interactions. To this end, I will answer four research questions (RQ):

• RQ1: What are current trends in flows of multiple pollutants from land-based sectors to water systems at the sub-basin scale worldwide?

• RQ2: What are future trends in flows of multiple pollutants from land-based sectors to water systems at the sub-basin scale worldwide?

• RQ3: To what extent do pollution levels exceed desired targets for clean water by multiple sectors at the sub-basin scale worldwide today and in the future?

• RQ4: What are effective measures to achieve clean water for multiple sectors at the sub-basin scale worldwide in the future?