Photo Credit: Rotterdam Ahoy

22 March is World Water Day. The Municipality of Rotterdam, Rotterdam Ahoy and Hago Nederland (cleaning company) are joining forces to start on the realisation of an urban water buffer (UWB), a system in which rainwater is collected, retained, filtered, stored and reused. This is the next step in a series of sustainability initiatives for Ahoy.

Drinking water is cheap, but freshwater is scarce. Most rainwater, which is originally clean, goes through the sewerage system to surface water or a sewage treatment plant (STP). The latter burdens the STP with relatively clean water making it less profitable. Reason enough for the three parties to start this project. Paved surfaces will be disconnected from the sewerage system so that the rainwater can flow to the water buffer.

How the urban water buffer works

The Gooilandsingel is being redeveloped by the Hart van Zuid area development project. The street will be transformed into a green city boulevard for pedestrians and cyclists. A crate storage facility will be constructed under the Gooilandsingel to collect the water from the roof of the Zuidplein Shopping Centre and the Gooilandsingel. In total, this concerns an area of 4.8 hectares. Heavy rainfall of 50 mm will produce 2,400 cubic metres of water. The water collected in the underground storage facility will be purified with plants and stored deep in the subsoil until it can be reused. The management expects to be able to reuse 20,000 cubic metres of the collected water annually, a fantastic result!


Rotterdams WeerWoord is the initiator and main financier of the urban water buffer in Hart van Zuid. This municipal programme was set up together with the water boards in Rotterdam and Evides. Climate change increases the risk of problems and damage from heavy precipitation, heat, drought and flooding. Rotterdams WeerWoord is preparing the city for a more extreme climate. The city is being made weatherproof for, with and by the people of Rotterdam.


Ahoy wants to use the water from the water buffer for window cleaning and floor cleaning; which will be carried out by Hago, its cleaning partner. The water will also be used to flush the toilets at the new Pathé cinema (completion 2024). This will save a total of 15,000 cubic metres of drinking water every year. If the bubble is big enough, the water can even be used to flush the Zuiderpark in the summer when the water quality threatens to deteriorate.

Sustainable future

Investing in sustainability initiatives is one of Ahoy’s top priorities. Jolanda Jansen, Managing Director says: ‘It is great to see how we are becoming more sustainable on various fronts step by step. The construction of our brand-new Rotterdam Ahoy Convention Centre offered us the opportunity to approach things more smartly and sustainably, but we have also implemented changes company-wide, for example, in the fields of hospitality and waste processing.’ All of the sustainable initiatives of the event complex are listed on