‘Schieland en de Krimpenerwaard’ is a regional water authority.

Its mission is to ensure dry feet and clean surface water in its catchment area which stretches from Rotterdam, Zoetermeer to Schoonhoven.

Within that area, Schieland en de Krimpenerwaard is responsible for flood control (maintenance of the dikes), water quantity (correct surface water levels), the quality of the surface water and the treatment of urban wastewater. Moreover ‘Schieland en de Krimpenerwaard is also responsible for the maintenance of some of the local roads in the Krimpenerwaard, but it is not responsible for drinking water production, the quality of swimming (recreational) water or the sewer system. These are the responsibilities of water supply companies, provinces and municipalities respectively.

Regional water authority

A regional water authority is a decentralised public body that can be compared to provinces and local municipalities. It is an independent organisation with defined legal responsibilities and a self-supporting financial system.

Catchment area

The catchment area of Schieland en de Krimpenerwaard can be found in the province of Zuid Holland and roughly covers a triangle between Rotterdam, Gouda and Zoetermeer. There are both rural and agricultural areas (dairy farms amongst others) and residential areas.

The catchment area of Schieland en de Krimpenerwaard

  • Size: approx. 33,600 ha
  • Pumping stations: 95
  • Municipalities: 9
  • Waste water treatment plants: 9 
  • River dikes: 71 km
  • Roads: 131 km
  • Local dikes and quays: 221 km
  • Cycle tracks: 40 km

Water quality

Schieland en de Krimpenerwaard is responsible for the quality of the surface water (open water) in the area. Urban waste water is pumped to one of the nine waste water treatment plants (awzi’ s) where it is treated before discharging into surface water. Other activities to improve the water quality include dredging watercourses and the construction of ecological embankments. These embankments are no longer steep but are sloping and are covered with water plants. This results in an attractive living environment for a variety of animals (especially fish) and plants that help improve the water quality.

Water level

Schieland en de Krimpenerwaard regulates the water level in waterways and watercourses that run through its catchment area. An extensive system of waterways, brooks, canals, ditches, ponds, and storage reservoirs is used to store water in wet seasons and to supply water in dry periods. The main part of our area lies beneath sea level and consists of polders and reclaimed land. Pumping stations ensure that the water is always at the required level.

Because of the different ways the land is used (i.e. various agriculture and urbanisation), the area maintains 184 fixed water levels as the water level has a direct influence on the use of the land.  

On the west side of the river the Hollandsche IJssel, Schieland en de Krimpenerwaard uses a ‘boezemwater’ system (a two-step water pumping system). Here the water is pumped from the polder to the storage canal and from there into the river. East of the river the Hollandsche IJssel (in the Krimpenerwaard), a one-step system is used so the water is pumped directly from the polder into the river or, if more convenient into ditches. In time this method of pumping will be replaced by the generally accepted two-step pumping system.  

Water boards are not responsible for the management of ground water.


The catchment area of Schieland en de Krimpenerwaard lies partially below sea level. Without dikes this area would be uninhabitable; it would be flooded. Schieland en de Krimpenerwaard ensures that the dikes are kept stable and at the required height.

There are several types of dikes:

  • Main water defences: dikes alongside a river
  • Quays : embankments or dikes alongside other waterways
  • Natural water defences: that serve as emergency water barriers

In order to ensure the stability of the dikes Schieland en de Krimpenerwaard  has set rules and regulations for activities and objects near or on water defences. These regulations are bundled in an official legal document called the ‘Keur’.

If the weather forecasts indicate extremely high water levels and storms the dike wardens are mobilised.


Schieland en de Krimpenerwaard is also responsible for maintenance of a number of roads outside the town centres, with the exception of provincial roads. This means that the regional water authority looks after road safety, road accessibility and road environment. So road and verge planning receives considerable attention. Another important part of road management is gritting in the winter to ensure the roads stay accessible.  

Spatial planning

People need space to live in, work in and enjoy leisure time. The challenge of spatial planning is to create sustainable areas for these purposes though the space is limited and the people concerned have different interests. The blue lines and areas on the map can help solve this puzzle. Water is everywhere. If we do not give water enough space it will take that space by force. Schieland en de Krimpenerwaard plays an advisory role in spatial planning and is involved in project development from the very beginning. In order to incorporate water in new neighbourhoods and recreational areas in the best way, it puts considerable time and energy into public and stakeholder participation. But there is more: Schieland en de Krimpenerwaard also helps decide the best spot for new neighbourhoods. Thus problems can be anticipated and prevented and everyone will profit from that. People can live and enjoy life safely, despite the fact that most of the area lies below sea level.

Schieland en de Krimpenerwaard never sleeps and works hard to ensure that we keep our feet dry, and also provide sufficient and clean surface water in its catchment area.