09. Nieuwe Driemanspolder - Leidschendam

The Nieuwe Driemanspolder is a peak water storage, nature and recreation area. Until 2017 this was still an agricultural polder, but between 2017 and 2020 this area was completely redeveloped. The result is a multifunctional area of over 300 hectares for climate adaptation, nature and recreation.

In Rijnland’s working area, an extensive system of drainage canals carries the water to the edges of the area. There, large pumping stations pump the water to the North Sea, the North Sea Canal and the Hollandse IJssel. But a huge amount of rainwater can be too much even for the pumping stations, resulting in flooding. A good solution is to capture the excess water in a peak water storage.

A peak water storage is a diked-off section of polder that serves as a temporary overflow for the drainage water. In the event of extreme rainfall, excess water is let into the storage area from the drainage system. Once the water level in the drainage system has dropped again after a few days, the water is returned from the peak water storage back into the system. Two peak water storages are being built in Rijnland’s area: one in the Haarlemmermeer and one in the Nieuwe Driemanspolder.

It takes about two days to fill the peak water storage. The water level in the storage rises by about one and a half metres. After about five days, the water is discharged from the west side of the area to the Stompwijkse Vaart. It takes about ten days for the peak water storage to be empty again. Due to climate change, it is expected that the use of the peak water storage will be needed more frequently in the future.

The Nieuwe Driemanspolder is not only a peak water storage, but also a beautiful nature area where you can enjoy recreation.