Meet environmental manager Eddi Ottens
December 10, 2025
The construction of the additional balancing lake De Onlanden is now underway. Environmental manager Eddi Ottens is taking over from Marina van Nimwegen and would like to introduce himself.

Familiar with De Onlanden?
“Absolutely! In 2012, I was already working at the water authority when the floods hit. Since then, various measures have been taken to prevent flooding. Creating more balancing lake one of them. I also have a personal connection to De Onlanden. I live on the edge of the area, go running there, and often cycle through it.”
What changes will be made to the existing balancing lake?
De Onlanden is already a water storage area, where water from the higher-lying province of Drenthe flows in naturally during heavy rainfall. Soon, a controlled balancing lake will be balancing lake . We are raising the existing quays so that we can retain extra water within them. weirs pumping stations that the water is collected in a controlled manner and gradually discharged into the sea. De Onlanden can currently collect 7.5 million m³ of water. With the additional balancing lake , the capacity balancing lake to 12.7 million m³ of water.”
When will it be ready?
"All work is expected to be completed in 2027."
How often do we use the extra balancing lake?
“Only in extreme weather conditions. The water will then remain in the area for several days. Full deployment is expected to be necessary once every 25 years on average. We may deploy part of the system once every 10 years.”
Questions or concerns?
Eddi is available to answer your questions.
Email: optimalisatieonlanden@noorderzijlvest.nl
Telephone: 06-51403752