World Water Day: Every drop counts!

22 March is World Water Day. Time to reflect on the key role water plays in everything we do. From storage over purification to reuse: Technics knows how to handle it!

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 mains 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.

Water treatment at a smaller scale

The installation in Halle is quite an impressive feat, but Colruyt Group wouldn't be Colruyt Group if we didn't also think small to make every penny count. We have over 500 own stores, which together account for 30% of our water consumption. In many of our stores, we already use rainwater to flush the toilets. There is more rain than we can flush, so we are examining whether we can purify that excess rainwater locally and reuse it as tap water.


When 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. By 2025, we want 50% of the total water consumption of our own operations to come from the sky - rain, snow, hail and/or thaw - as well as from waste water. We strive towards a zero discharge of rain water in the sewers and less use of 'new' tap water (mains water). We are therefore constantly looking for smarter ways to use the precious resource that is water.

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