Water Framework Directive (WFD) Fish Passes
In early 2025, we began addressing several fish migration bottlenecks by realise new fish passages at eight designated fish migration bottlenecks.
Why are we working on the Water Framework Directive?
The Water Framework Directive (WFD) is a European directive. The purpose of the directive is to protect and improve the quality of surface water and groundwater in Europe. For the purposes of the WFD, Europe is divided into river basins. For catchment , so-called River Basin Management Plans (RBMPs) catchment be drawn up, setting out chemical and ecological objectives for each body of water and a binding program of measures. Since the implementation of the Water Framework Directive, the Netherlands has made significant progress in improving water quality.
The Importance of Fish Migration
Fish migrate between different habitats throughout their lives. If they cannot reach those habitats, they cannot survive—whether as individuals, populations, or species. Over time, humans have erected all kinds of migration barriers for fish—such as pumping stations, weirs locks—to facilitate other uses of the waterways. Because of these barriers, fish stocks in a number of water bodies within Noorderzijlvest’s management area are not in good condition. The Water Framework Directive aims to improve ecological water quality. The WFD requires European member states to address such issues, such as significant barriers to fish migration.
Fish passages contribute to WFD goals
Making migration barriers fish-passable and fish-friendly ensures that fish—as well as aquatic insects—can reach and utilise their habitats without too much difficulty. Together with addressing the other prerequisites for fish, making the barriers fish-passable and fish-friendly should ensure that the WFD targets for fish populations are achieved.
Why were these locations selected?
Barriers to Fish Migration
A balanced and healthy aquatic ecosystem requires a healthy and diverse fish population. flood defence weirs flood defence pumping stations weirs —can act as a barrier to this, since many fish species migrate between different bodies of water.
Major Fish Migration Routes
There are several hundred weirs, pumping stations locks within Noorderzijlvest’s management area. These structures prevent fish from accessing the habitats they need. The presence of these obstacles is one of the reasons why fish population targets have not yet been met in various water bodies. The fish migration plan maps out the most important fish migration routes within Noorderzijlvest’s management area. These routes largely coincide with the main drainage system and with the WFD water bodies.
Part of a larger project
These eight bottlenecks, which are being addressed as part of this project, are part of a larger effort. To meet the WFD objective, water authority must still carry out a remaining task to resolve fish migration bottlenecks.

What are we going to do?
Considerations and Decisions by Location
These eight bottlenecks have been developed into a preliminary design, but in order to do so, a number of considerations and decisions must first be made, taking into account, among other things, water level management, the status of the structure, and the system’s performance. In addition, an assessment was conducted to determine which fish migration systems are suitable for the selected locations. All of these factors were weighed together, leading to preferred solutions for each location.
Preferred Solutions
At 6 pumping stations , the preferred solution pumping stations a Vislift Up, and at the other two bottlenecks, a Fish Track and a De Wit passage will be installed.



What's next?
Development of the Designs
Noorderzijlvest is working with Arcadis and contractor De Boer en De Groot to further develop the designs. Based on these designs, the necessary permits will be applied for and preparations realisation construction will be made. De Boer en De Groot will then carry out the realisation work.
Schedule by Location
Below is the schedule for the preparation, permitting, and execution of the work at the eight locations.
Casper Hommes Pumping Station, Vislift-up system (Zuidwolde) | |
| Preparation | Quarters 2 and 3 of 2026 |
| Permit Process | Third Quarter of 2026 |
| Implementation | Quarters 3 and 4 of 2026 |
Tilburg Pumping Station, Vislift-up system type (Winsum) | |
| Preparation | Quarters 2 and 3 of 2026 |
| Permit Process | Third Quarter of 2026 |
| Implementation | Quarters 3 and 4 of 2026 |
Garsthuizen Pumping Station, Fish-track system (Garsthuizen) | |
| Preparation | Quarters 3 and 4 of 2026 |
| Permit Process | Fourth Quarter of 2026 |
| Implementation | Quarters 1 and 2 of 2027 |
Katerhals Pumping Station, Vislift-up system (Appingedam / Hoeksmeer) | |
| Preparation | Quarters 3 and 4 of 2026 |
| Permit Process | Fourth Quarter of 2026 |
| Implementation | First Quarter of 2027 |
Transferium Pumping Station, Vislift-up System Type (Hoogkerk) | |
| Preparation | Quarters 3 and 4 of 2026 |
| Permit Process | Fourth Quarter of 2026 |
| Implementation | First Quarter of 2027 |
De Wolden Pumping Station, Vislift-up system (Zuidwolde) | |
| Preparation | Quarters 3 and 4 of 2026 |
| Permit Process | Fourth Quarter of 2026 |
| Implementation | Quarters 1 and 2 of 2027 |
Loppersum Pumping Station, Vislift-up system type (Loppersum) | |
| Preparation | Quarters 3 and 4 of 2026 |
| Permit Process | Fourth Quarter of 2026 |
| Implementation | Quarters 1 and 2 of 2027 |
Olnijster Weir, De Witpassage Type (Onderdendam) | |
| Preparation | Quarters 3 and 4 of 2026 |
| Permit Process | Fourth Quarter of 2026 |
| Implementation | Quarters 1 and 2 of 2027 |
Grants and Contributions
CAP Subsidy
The CAP (Common Agricultural Policy) grant is a European program. CAP grants have been obtained for four of the eight fish migration bottlenecks. The project is therefore co-financed by the European Union. This applies to the following locations: De Wolden Pumping Station, Casper Hommes Pumping Station, Garsthuizen Pumping Station, and Karterhals Pumping Station. CAP grants are intended for agricultural entrepreneurs, nature and landscape organizations, research institutions, government agencies, and partnerships, and support the following activities, among others:
- Enhancing Nature, the Landscape, and Biodiversity
- Improving Animal Welfare
- Comprehensive, area-specific approach to the environment, climate, biodiversity, and water
- Improving Water Quality

subsidence Committee
Within these eight fish migration bottlenecks are a number of structures built to address subsidence gas extraction in relation to the water system and water level management. Because these facilities (pumping stations and weirs) were originally built with funding from the subsidence Commission, the fish migration bottlenecks are now also partially funded by the Subsidence Commission.