Kees Roest speaks at Fosfaatspagaat Symposium

On Sunday, 19 November the Fosfaatspagaat Symposium was held in the Metaal Kathedraal in Utrecht. The event was organised by the

Slow Food Youth Network (SFYN) is an international youth movement dedicated to a good, clean and fair food system. As part of the international Slow Food Network, SFYN wants to promote good food that is produced as sustainably as possible and for which the farmer receives a fair price.

Utrecht together with SF Utrecht and the Metaal Kathedraal. SFYN Utrecht’s annual theme is ‘Poep onder de loep’ (‘Taking a look at poop’), and they organised the symposium to delve more deeply into the subject.

During the symposium Renske Verhulst, of the Nutrient Platform, gave a great presentation on a cross-sectoral network of 35 organisations dedicated to closing the nutrient loops and creating markets for recycled nutrients. KWR is a member of the Nutrient Platform.


Phosphorus is a vital element for all life on earth. It’s like oxygen and water. And phosphorus has no substitute – so, no phosphorus, no us. The supplies of this element are however finite and unevenly distributed over the planet. This, at a time when in the Netherlands there’s talk about excessive manure that results in much of our agricultural land being phosphorus-rich. At the same time, the excessive phosphorus contaminates surface waters, and this valuable raw material is often seen as waste.

Recovering phosphorus from wastewater

After the break I spoke about the TKI Sustainable Airport Cities project. The project involves the recovery in a pilot of phosphorus (struvite) from Schiphol’s wastewater. The recovered phosphorus product is tested for quality and contamination. After establishing that it meets legal requirements for recovered phosphorus, it is used as an alternative to the artificial fertilisers used at the airport. Today, phosphorus is being recovered at several wastewater treatment plants in the Netherlands and some abroad as well. This was the subject of the VPRO programme ‘Tegenlicht’ in March 2014.


TKI Sustainable Airport Cities project explained in short video.

Then, in parallel, small-group sessions, discussions were conducted under Geert Boink (SZH) about the regulatory and legal framework and rare domestic breeds, Henk van Reuler (WUR) about artificial fertilisers, Renske Verhulst about creating markets for circular initiatives concerning phosphorus, and Linda Grotenberg (Riverfood) about Aquaponics.

The importance of phosphorus recovery

The urgency and the need for attention for the looming phosphorus shortage, and the related importance of phosphorus recovery, is underlined by Tinkebell, an artist who made a film about the subject in 2013. The film was projected in the evening following the closure of the symposium.


Artist Tinkebell underlines the importance of phosphorus recovery.

Poep onder de loep

Sunday, 19 November, was an appropriate date to talk about the phosphorus challenge in the framework of the SFYN’s  ‘Poep onder de loep’ theme because, as I mentioned in my introduction, it was also World Toilet Day. Besides the collection and safe processing of excrement, it is also important that the valuable components, like phosphorus, be recovered and reused. Thanks to the symposium the attention of more people was turned to the subject, which helps promote awareness.