Measures in and around rivers

Measures in and around rivers

Our rivers need to discharge ever more rainwater and meltwater. We are taking various steps to protect our country, such as widening watercourses and making the dykes more effective.

We used these in the Room for the River and Maaswerken programmes, and are still using them today.

Dyke relocation

We move the dykes further inland, which makes the floodplains more extensive. That helps give the river more room, and there is more space to absorb high water.

High-water channel

Another option is discharging excess water via a high-water channel. The channel is a branch of the river that we create by building two extra dykes in the landscape. At high water, some of the river water is then diverted via another route.

Lowering of perpendicular groynes and building attracting groynes

Sometimes we lower a groyne (a short stone dam at right angles to the river) or build attracting groynes (parallel to the river). This helps with the discharge of the river water.

Removal of obstacles

Sometimes there are obstacles in the river: jetties or bridge heads, for instance, that form an obstacle to the flow of water. We modify or remove them.

Depoldering

Depoldering is where we move the dyke further inland. This means that the river can flow into and out of the area at high water.

Lowering the flood plain

Over the centuries, floodplains have risen due to deposition of substances such as sand and clay. By lowering flood plains, we can give the river more room at high water.

Water retention

Occasionally we store excess water, as is the case in the Volkerak-Zoommeer. We do this where river water can no longer be discharged into the sea because theĀ Maeslant storm-surge barrier, Hartel storm-surge barrier and Haringvliet lock complex are closed.

Deepening the summer bed

By excavating the ground, we lower the river bed. As a result, the river bed will be deepened. This allows more space to accommodate the water.

Improvement of dykes

Where space is unavailable for the widening of watercourses, the dyke can be strengthened and, if necessary, raised.