Water storage

There are periods when a lot of precipitation falls in a short period of time. Sometimes there is so much that there is a risk of flooding. The water authority excess water to the sea. When water levels are high, this is not always possible immediately. In that case, we temporarily store the water in areas that have been specially designed for this purpose. We then slowly drain the water to the sea. This way, we keep our feet dry.
 

Water storage facilities in our region

We drain excess water into the sea. If we don't, we will have to deal with flooding. Sometimes the sea level is higher than the water level in the rivers, canals, streams, lakes, and ponds behind the coastline. In such situations, we cannot drain any additional water. After all, water flows from high to low. The climate is changing and the chance of heavy rainfall in a short period of time is increasing. That is why we are creating areas where we can temporarily store water before draining it. This ensures that we keep our feet dry. We have now region a number of such storage facilities in our region .

Water storage facility De Onlanden

In 1998, heavy rainfall caused flooding in the northern Netherlands. We didn't want that to happen again. That's why, between 2000 and 2014, we developed an area where we can store water: De Onlanden. It is located between Groningen, Eelde, and Leekstermeer and covers 1,700 hectares. 
The balancing lake De Onlanden can store up to 7.5 million cubic meters of water. The greater the flooding, the larger the area where we store water and the more water it can hold. 

The construction of this balancing lake completed in 2014. It has developed into a beautiful nature reserve with lots of water, plants, and animals. There is also space for agriculture and recreation. 

Storing more water in De Onlanden

This balancing lake currently unable balancing lake store enough water to ensure that our residents can continue to live safely with water in our region in the future. The Bestuur of Directors Noorderzijlvest therefore decided at the end of 2018 to balancing lake the balancing lake . In concrete terms, this means: 

  • In the future, the balancing lake be able to handle a maximum water level of 15 centimeters above Amsterdam Normal Level. Currently, the balancing lake can handle balancing lake maximum water level of 20 centimeters below Amsterdam Normal Level. A difference of 35 centimeters.
  • This means that more water must be able to be stored in the area in extreme situations: an additional 5 million cubic meters (in addition to the 7.5 million cubic meters that is already possible). With this plan, the water authority will be able to raise water authority water level further than is currently possible on an occasional basis.
  • We weirs automated weirs : the storage facility will start working as soon as conditions require it.
  • We need to raise existing quays around the area in some places.
  • A new flood defence is being flood defence between De Onlanden and Leekstermeer. 

These additional measures have consequences for the use and layout of an area larger than the boundaries of De Onlanden. That is why we are going through the process of balancing lake the function of the balancing lake with our partners, the province of Drenthe, the municipalities of Tynaarlo and Noordenveld, Staatsbosbeheer (the Dutch Forestry Commission) and Natuurmonumenten (the Dutch Nature Conservation Society).

Water storage facilities in the Southern Westerkwartier

The province of Groningen and the water authority jointly responsible for the overall development of a large area in the Zuidelijk Westerkwartier. A special area committee is working with many other parties to carry out all the work. In this area, nature development and the construction of balancing lakes go balancing lakes in hand. Passers-by on the A7 between Drachten and Groningen can clearly see the progress of the work. 

Water storage is one of the aspects we are implementing in the Zuidelijk Westerkwartier. It involves:

  • Designing abalancing lake nature area in "De Drie Polders" with a capacity of 1.3 million cubic meters of water.
  • Designing balancing lake nature area within the "De Dykes" polder with a capacity of 1.2 million cubic meters of water.

Want to know more?

The project in this vast area involves much more than just storing water. You can find out everything about the project on a special website.

Mountains or water retention: what is the difference?

Now that dry periods are becoming more frequent, many people are wondering why we continue to discharge so much water into the sea instead of retaining it in the area. The answer is simple: we have to continue to discharge large amounts of water because otherwise we would no longer be able to live safely in our country. We sometimes have to discharge millions of liters (at once).
We store water to prevent flooding. We store water in low-lying areas. We store the water for a while and then slowly discharge it into the sea.
Of course, the water authority is water authority of the need to retain water for longer. We do this to get through times of scarcity and to maintain sufficient water in every season.

In the projects we carry out, water storage and water retention often go hand in hand. However, other measures are needed to retain water for longer periods of time.