Nearly 40 years after completion, major portions of the electronic installations at the Haringvliet locks and the Volkerak sluices are nearing the end of their life spans.

Therefore, the existing operating and control systems, the energy distribution systems and parts of the mechanical installations are to be replaced. This ensures the continued reliability and availability of the complexes. The work started in 2007 and will continue through to 2010. After this, HOMIJ will be responsible for maintenance until 2025.

Role of Grontmij
Grontmij supports HOMIJ with a team of approximately 15 people. We are, among other things, responsible for drafting the preliminary design and for drawing up the final design according to the principles of Systems Engineering and Life Cycle Management.

Additionally, Grontmij has an important role in the management of external communication regarding the project to interested parties and stakeholders in the area and in obtaining all the necessary permits. Drawing up the calculations for establishing the required reliability and availability and supporting the process of realisation are likewise among our tasks.

Volkerak locks
The Volkerak locks complex is situated on one of the busiest waterways of Europe: between Rotterdam and Antwerp. In addition to a special pleasure yacht lock, the complex has three major locks for commercial shipping, across which lies a double bascule bridge for the A29 motorway.

A risk analysis of the mechanical and electrical installations of the Volkerak locks showed that these installations were no longer sufficiently reliable. A large-scale renovation is thus imperative. The entire operation takes place under the strict condition that shipping is disrupted as little as possible.

Haringvliet sluices
The Haringvliet estuary is closed off on the side of the sea by the Haringvliet dam, a primary diversion dam. One part of this dam is the 56 metre wide complex of sluices with seventeen steel gates: this complex drains excess water from the Rhine and may be described as the tap of the Netherlands.

Even during very harsh winters, the sluices can be opened. After renovation it will be possible to open the sluices partially, so as to allow tidal movement to return to the estuary. The (restricted) admission of sea water will allow for the recovery of the original ecological system of the Haringvliet.