© Royal HaskoningDHV

The challenge

The Hoorn - Amsterdam dike section forms part of a ring of water barriers that protects the province of North Holland. According to the current standards, the stability of the dike can no longer be guaranteed under extreme conditions such as long-lasting high water levels on the Markermeer. It is necessary to reinforce the dike (over approx. 33 km) to be able to continue to protect the population and the land against flooding. The dike needs to be reinforced in an area with very soft ground (peat), protected rural views, a rich cultural history, a main ecological network, an intensive recreation, and a somewhat limited access.

The solution

The purpose of the dike reinforcement is to guarantee the safety of the dike section for at least 50 years. The objective is to create a safe, future-proof water barrier that is appropriate to its environment. The existing functions and valuable elements are retained as much as possible and the opportunities for these aspects are utilised.
Water Board Hollands Noorderkwartier has commisioned Royal HaskoningDHV not only to work out the details, but also to play an important role in the project management and process management, in the internal and external communication and in developing a vision for the project.

The result

Royal HaskoningDHV is responsible for drawing up the project initiation documentation, many additional studies, the environmental impact assessment report and associated investigations, permits, SE, spatial quality framework, 3D hydraulic engineering design, visualisations, integrated design, cost estimation, realisation advice and, finally, the dike improvement plan. These reports take stock of and assess different approaches to solutions. This includes innovative concepts such as the Oeverdijk. The 'Dijken op Veen' (dikes on peat) study was integrated as much as possible. In part by using this, and on the basis of a description of the current spatial quality of the dike and the defined design criteria, variants have been established for each dike section. The designs of the preferred alternatives that are determined for each dike section are worked out in the dike improvement plan.