Comparitive sampling workshop on Micro-litter in the Drava River (Maribor)

As part of Activity 1.1 of the Interreg Aquatic Plastic project, the Institute for Water of the Republic of Slovenia (IWRS) organised a two-day expert workshop in Maribor (10^th and 11^th of September), titled “Comparative Sampling and Micro-Litter Collection in the Drava River.”

The aim of the workshop was to align different approaches to river micro-litter sampling using water pumps and nets, in order to ensure comparability of results among project partners through methodological harmonisation and exchange of best practices.

The workshop brought together key project partners from Slovakia (VÚVH), Austria (BOKU), Slovenia (IWRS), and a representative from Eurofins, with the aim of harmonising approaches for micro-litter sampling in rivers. By standardising methodologies and sharing experiences, the project partners seek to ensure comparable and reliable results across pilot sites in different countries.

Workshop Objectives:

• Comparison of different sampling methodologies for microplastic sampling in rivers – sampling in parallels;

• To exchange experience and good practices among project partners;

• To ensure comparability of results through standardised methodologies;

• To strengthen collaboration and knowledge transfer among experts.

Day 1 – Theoretical Session

The workshop opened on 10 September 2025 with presentations of sampling methods used by the project partners. Participants shared procedures, equipment, and lessons learned from previous fieldwork.

The workshop opened on 10 September 2025 with presentations of sampling methods used by the project partners. Participants shared procedures, equipment, and lessons learned from previous fieldwork.

The theoretical session was an open discussion on how to carry out comparable sampling methodologies. After the official programme and coffee break, participants joined a networking dinner hosted by IWRS.

Day 2 – Practical Sampling on the Drava River

The second day focused on hands-on sampling on the Drava River at the closed section of the Meljski most bridge.

Partners carried out coordinated sampling using manta nets (for surface water) and water pumps (for the water column). This practical exercise allowed the teams to test and exchange knowledge in order to agreed protocols and will enable direct comparison of results in the next stages of the project.

Importance of the Event

This workshop was an important step towards developing a common methodology for riverine micro-litter monitoring across the Danube region. By harmonising approaches, the project supports more effective data collection, better understanding of pollution sources, and informed decision-making for future river management plans.

Participants at the workshop explored how different sampling approaches used by project partners influence the comparability of results. All partners sampled simultaneously, at the same bridge and river sections, using slightly different equipment – and we are eager to see what the results will reveal.

While many steps remain to be harmonised, (e.g. the laboratory phase), this marks an important first step toward a comparable results. We look forward to the first laboratory analyses being completed — and will gladly share the findings with you in the coming months.