In Nice, a walk into the future.

Haliotis 2 is a story of a remarkable facility installed on one of the most beautiful coastal bays in the world. It is also an adventure for our team! They worked for two years to win this contract which constitutes our largest wastewater project in the last 15 years. More than 100 SUEZ employees were involved in the bid. This contract is above all a collective accomplishment, with collaboration between operational and administrative disciplines, between local teams and head office, and between the various entities mobilised (Construction France, Construction International, Water France and cross-group support departments). All of which offers proof that solidarity between all our entities and their respective areas of expertise can deliver performance. 

Our teams will lay the first stone in this iconic project in July 2024. When it comes onstream in early 2029, the new plant will process the wastewater of 26 municipalities. Haliotis 2 will filter out 90% of microplastics and will be fitted with an industrial micropollutant¹ treatment demonstrator running at 150 m3/h. These beneficial processes will offer further protection to the Mediterranean and biodiversity.

As early as 2028, the Greater Nice area will have a treated wastewater reuse unit capable of recycling more than 5 million cubic metres of water per year. According to Mathieu Delahaye, a resource conservation expert at SUEZ, “one of the major impacts of climate change is the increasing scarcity of water resources. Haliotis 2 will meet the challenge by reusing treated wastewater.” This will supply all the water required for green space irrigation and street cleaning in Nice.

With Haliotis 2, our teams have created a project that rises to the challenge of the energy transition. The plant will generate 475MWh of green electricity thanks to a solar farm, and 43GWh/year of biomethane through the processing of sludge. What does that mean in practice? The biomethane will be reinjected into the GRDF network to heat approximately 11,000 housing units or supply the equivalent of 290 buses with biofuel. The electricity generated, meanwhile, will make the administrative building self-sufficient.

In parallel, the recovery of calories and frigories² following the treatment of wastewater will also feed into a heating network supplying 6,500 housing units. “Haliotis 2, by becoming the producer of an energy mix, will be able to adapt to market conditions”, explains Christelle Metral, renewable energy market specialist at SUEZ. “In the future, it could even contribute to the Greater Nice Council’s hydrogen plan and also produce synthetic methane.” 

The site will also be substantially rewilded, thanks to a design that will see the de-sealing of soil and the planting of 600 trees and hedges (30% additional permeable surface area). Green spaces will span 4.5 hectares: a genuine pool of biodiversity at the heart of Nice. According to Mark Wilson, associate architect and director of Groupe 6, “What’s exciting about this project is to develop a space that will be loved by the people of Nice. There isn’t another wastewater treatment plant in the world with a setting like this.” 

1) Endocrine disruptors, emerging substances.

2) Unit of measurement equivalent to the calorie in the refrigeration industry.

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