Between Sea and Source Westerwoldse Aa

The field trip “Between Sea and Source Westerwoldse Aa” is sold out. If you are interested in being placed on a waiting list, please feel free to reach out to Neža at
About the field trip

The Westerwoldse Aa catchment is situated in the Eastern part of the Province of Groningen and forms a section of the border between The Netherlands and Germany. Although the river and its tributaries only flow over a distance of 80 km, the rivers in this catchment are considered to be part of a rich succession of varying habitats, including wetlands, flowing freshwater streams and estuaries. The system provides valuable habitat for migratory fish species and is considered to be a rather unique system for The Netherlands. Over the last 3 decades river restoration and habitat improvement work has been carried out to restore en rehabilitate large sections of the Westerwoldse Aa catchment. Resulting in over 30 km of river reconstruction and 2,500 hectares of new nature areas. This work, carried out by Regional Water Authority Hunze en Aa’s, Province of Groningen, Prolander, Natuurmonumenten, Staatsbosbeheer, and numerous other organizations, was completed in 2021. For more information    

To evaluate the results of the work carried out, a long-term research program is now studying the effects of improved fish passage and habitat restoration in the Westerwoldse Aa catchment. Much of this work is undertaken as part of the Waddenfund project “Ruim Baan voor Vissen 2” ( 


During the tour, you will get an opportunity to visit some of the fishways and habitat restoration projects where you will hear more about the projects and monitoring results by leading experts Peter Paul Schollema, Jeroen Huisman, and Donné Mathijssen. 

Themes covered

Fish migration, habitat restoration, policy, implementation, research, tidal areas, canal systems, small rivers. 

Important information 

Price for Between Sea and Source Westerwoldse Aa field trip is €50.82 (inc. tax) and it includes guide, travel and lunch.  

Meeting place is the Groningen bus station at 8:30. Bus will leave at 9:00, be at the meeting place at least 15 minutes before departure. Planned return to Oosterpoort is by 19:00.  

Organised by
  • Peter Paul Schollema (Regional Water Authority Hunze en Aa’s),  
  • Jeroen Huisman (Van Hall Larenstein University of Aplied Sciences),  
  • Donné Mathijssen (Wageningen University)  

Drone picture Nieuwe Statenzijl

Drone picture Wessinghuizen