Sustainable water use: every drop counts!

From storage over purification to reuse: how Technics deals with water

Water treatment at a larger scale

At the end of 2021, we commissioned a brand-new water treatment plant in Halle. This plant treats industrial and sanitary waste water from 3 sites: our head office, our distribution centre and the offices and warehouses of a third site. The plant can produce 11 m³ of drinking water every hour. On an annual basis, up to 90,000 m³ of waste water is treated into 81,000 m³ of 'process water'. To turn process water into tap water, we have to remineralise it by adding 20% of mains water.

90% less city water

Besides the impressive treatment plant, we are also busy redefining our underground water management at our head office. We recently expanded our buffer capacity by 5,400 m³. In total, we can now store up to 9,500 m³ of rainwater. We collect that water and purify it using different technologies, including a sand and UV filter, after which we use it in our refrigeration systems and for our sanitary facilities. Thus, we manage to reduce our mains water consumption at our sites surrounding the head office by 90%! An additional benefit is that we are a lot less dependent on that mains water in periods of drought.

Active water management

At Colruyt Group, we promote conscious and active water resource management at our sites. For every building project, both renovation and new projects, we try to minimise our water footprint from the design phase on. We are looking at how we can reuse rainwater as much as possible and, if the subsoil allows it, we allow the remaining rainwater to infiltrate the soil. Only if this is not possible will we buffer the water on our site during peak downpours so that it can be discharged slowly. We maximise our reuse by looking critically into what water source we want to use for what purpose. The floor in a store for example can perfectly be mopped with rainwater to save drinking water. At Fine Food Meat, our site for meat processing, we also took some initiatives to organise our water consumption sustainably and efficiently.


On that site, there are three water purification stations. The PURA-station (PUrification of RAinwater) goes beyond the rainwater buffers on our other sites en purifies the collected rainwater into drinking water. We are also working on the waste water of our meat production. That water is too polluted to discharge in the sewers and has to be purified. That purification is done with a biological installation where we mix the waste water with active slit - a mix of micro-organisms that will digest the waste. After that, we separate the slit from the water, which is now clean enough to be discharged. But this water doesn't end up in the sewers: we go one step further and send it to the last purification station at Fine Food Meat.


Meat processing is very water-intensive. A lot of drinking water is needed, not only for the production of meat preparations, but good quality water is needed also for cleaning the machines in a production environment.

Lize Linclau, R&D engineer
That third purification station is there to organise that water usage in the most sustainable way possible. By using membranes, it filters the purified waste water further to drinking water, that we then re-use in the production process


When we are faced with drought, storing, purifying and reusing water is an ideal solution. But what if the rain is coming down in bucketfuls? Then we protect our stores and lower the pressure on the sewer system. By making smart choices in our design and layout, we reduce the risk of severe flood damage. Just think of our technical installations, which are high and dry on a platform.

We keep the rain out, but of course that water has to go somewhere. To relieve the burden on the sewer system during heavy rainfall, we are considering creating water roofs. That way we not only retain the rainwater on the roof, we also drain it in a delayed manner. As a result, we flatten the peak and the sewer system does not get to handle all that water at once. In Ninove, we combined such a water roof with a magnificent green roof.

Joining hands to manage water resources

Through the years we have built extensive knowledge and expertise in water management, but we cannot do it on our own. In Veurne for instance we have joined the Suikerpark project. We are exploring how we can donate the water we collect from the roof and car park of our Colruyt, Bike Republic and Dreamland stores to water basins in the nearby nature preserve. 

As you can see, within Technics, water is like a river, it never stands still!

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