Veolia Eau, operator of the MAERA wastewater treatment plant (WWTP) in Montpellier, France, works with BiOceanOr to better understand and limit the impact of discharges on the river basin. Launched in 2024 and now entering its predictive phase, the project shows how BiOceanOr’s environmental intelligence reaches beyond aquaculture, to support urban water management.
During heavy rainfall, part of the wastewater may be released directly into the river to protect the network, through storm overflows or at the head of the plant. These discharges can bring organic matter and nutrients into the Lez river, affecting water quality:
The challenge is to understand the real impact of these discharges on the river, in order to adjust and limit them according to environmental conditions, through better-informed operations.
Phase 1 focused on building a solid, data-driven picture of the Lez river, combining new measurements with Veolia’s historical datasets:
Together, the services enable Veolia to detect data inconsistencies and correlate water quality with rainfall, river flow and discharge volumes, through dedicated indicators of hypoxic risk and eutrophication.
Building on these insights, Phase 2 of the contract will develop a tailor-made tool to help Veolia adjust plant operations according to the expected impact on the river, for example by shifting a discharge to a moment when the environment is less vulnerable.
Veolia operates the MAERA WWTP for the Régie des Eaux of Montpellier Méditerranée Métropole, which manages the local water network. BiOceanOr works closely with Veolia’s operational teams to keep the indicators simple, actionable and grounded in field reality.
The project draws on BiOceanOr’s expertise in:
The project covers the Lez river basin, from Montpellier’s urban areas to below the MAERA plant, near the Mediterranean coast, where water quality also matters for bathing and coastal ecosystems. Its impact therefore reaches well beyond the WWTP, benefiting the whole region.
Beyond Montpellier, many territories face similar challenges. This is why BiOceanOr and Veolia are partnering to bring this approach to other sites and facilities.
Phase 1 was completed in early 2026, laying the groundwork for a predictive approach. Phase 2 starts in October 2026 and will run until 2031, focusing on the development of a digital tool to adjust WWTP operations according to the predicted impact on the river.
