Province of Fryslân contributes nearly €14 million to the development program. Wetterskip Fryslân intends to allocate over €9 million for the total development of the Koningsdiep.

Development program: a natural and climate-resilient valley

An environmental impact report has been prepared for the development program. This is a study on the effects on nature, water, agriculture, and landscape. Various options were compared. The preferred option combines goals for nature and water and takes into account other uses of the valley, such as housing. Together with Wetterskip Fryslân, LTO Noord, Staatsbosbeheer, Natuurmonumenten, It Fryske Gea, and the municipality of Opsterland, this option has been further developed in the program.

The program has three main goals:

  • Development of 350 hectares of new nature in the valley (Dutch Nature Network - NNN);
  • Improved water quality through the construction of meanders (bends) in the stream and two fish passages (European Water Framework Directive - WFD);
  • A climate-resilient valley by better retaining, storing, and slowly releasing water (Water Management 21st century - WB21).

In addition to the main goals, several recreational measures are included, such as the construction of a walking path and three experience points.

Deputy Matthijs de Vries of Province of Fryslân: “With this program, we take an important step for nature and water in Fryslân, with attention to agriculture. The plan for the development of 350 hectares for the Dutch Nature Network (NNN) was created together with involved parties and landowners. Together we work on a valley ready for the future.”

Gerben de Boer, daily board member of Wetterskip Fryslân: “By working together, we can create not only new nature but also significant water storage in the valley and achieve our goals for the European Water Framework Directive. During extreme rainfall, water discharge from the valley to the Frisian boezem, the system of lakes, canals, and waterways, is reduced by up to 45 percent. This helps prevent water nuisance elsewhere in Fryslân.”

Implementation plan: step-by-step development

Discussions are held with landowners and other stakeholders in the upper and middle course of the Alddjip. Because not all land is available yet, development is carried out step-by-step. Work can start first in the upper course, between Bakkeveen and the Mounleane, near Wijnjewoude and Ureterp. This concerns over 200 hectares for which an implementation plan has been prepared for the coming years. The remaining 150 hectares will follow.

The process: inspection and final adoption

If the general board of Wetterskip agrees with the development program, it will be available for inspection together with the implementation plan from December 1, 2025, to January 12, 2026, at the provincial office and the water board office in Leeuwarden. The documents and response form will be digitally available via www.fryslan.frl/koningsdiep. During the inspection period, walk-in meetings will be organized in the area.

After the six-week inspection period, the province will process the responses. Then the final development program and implementation plan will be drawn up. In spring 2026, the Provincial Executive, with the consent of Wetterskip, will adopt the final plans and prepare the execution with involved parties and owners. Province and Wetterskip expect to carry out the work between 2026 and 2030.

Background

In the 1960s, the course of the Alddjip was adjusted and the area better developed for agriculture. Since 2007, work has been done on new nature along the stream, with more space for water. Currently, 225 hectares of new nature have been developed in the western part of the valley. After years of preparation, there is now a clear plan for the east: the upper and middle course. More information about the Koningsdiep can be found at www.fryslan.frl/koningsdiep.