Major monitoring campaign launched to improve Ems-Dollart water quality

Published: 28 August 2018

The sludge suspended in the water of the Ems-Dollart region makes it turbid. Led by Rijkswaterstaat, eight ships and eighteen partners began a major survey here today. The monitoring campaign is a unique collaboration involving the Netherlands and Germany: the water management authorities from the two neighbouring countries want to reduce the amount of sludge and improve water quality. Deltares is providing models to predict the effects of potential measures.

The large quantities of sludge in the water of the Ems-Dollart retard the growth of the algae that make up the base of the food chain. Life in the bed of the water and fish also suffer. The large-scale field study starting in the Ems estuary today will provide a clearer picture of how the sludge behaves in the dynamic transition area between the river and the sea (fresh and salt water).

Major advances in understanding of complex transport processes in turbid water

The data that will be collected should provide answers to questions such as: why does sediment travel from the estuary in the direction of the Ems river, why does so much sediment settle in the waterway to the Emden (the link between the river and the estuary), what happens when discharge rates are high, and what is the impact of turbidity in the river on the estuary? The knowledge that Deltares has about modelling turbidity, morphological changes and water quality is being applied here.

Bas van Maren, an expert in sediment transport and morphology, will be on one of the survey vessels: ‘Monitoring campaigns like this with eight ships, seven monitoring frames and so many experts have been unknown since the 1970s. They are very expensive. But by pooling forces, specialised equipment and expertise, it has been possible to get things off the ground. And many of the institutes are actually participating on a voluntary basis because our understanding of complex transport processes in turbid water will be greatly increased.’

Results due in the summer of 2019

The first 13-hour measurement from the vessels will be conducted on 28 August. The second round of measurements will take place during the expected high discharge of the Ems river between 9 January and 10 February 2019.

In addition to the surveying work from the ships, ten monitoring frames (see photo) will be installed on the bed of the estuary to measure turbidity, salinity and flow velocity for three weeks at various depths.

Publication of the initial results is expected in the summer of 2019.

Monitoring frame, photo Rijkswaterstaat

Participants in the study

Rijkswaterstaat,  Royal HaskoningDHV, German authorities: BAW-DH, NLWKN Norderney, Bundesanstalt für Gewässerkunde, CAU Kiel, WSA Emden, NLWKN Aurich, Netherlands Institute for Marine Research (NIOZ), International researchers from Oldenburg University, CAU Kiel, University of Warnemünde in Rostock, HR Wallingford, University of Maine, Delft University of Technology, Twente University of Technology and Wageningen University and Research Centre.

Ems-Dollart 2050 Programme

The research is part of the Ems-Dollart 2050 Programme, an initiative of the Dutch Ministries of Infrastructure and Water Management, and Agriculture, Nature and Food Quality, as well as the provincial authority of Groningen. It brings together water authorities, municipalities, ecology organisations and the business community to work together on improving ecology, nature and flood risk management while promoting a sustainable economy and the living environment in the Ems-Dollart region.