The water retention basins were designed along the route of the T12 tram-train

Water treatment and management are a major issue today. Since 2021, as part of the construction of the T12 tram-train, 7 water retention basins have been created.

These underground or open-air basins have several functions, essential to rainwater management in urban areas:

• Storing water temporarily to avoid flooding downstream,
• Limit runoff water by collecting water from the platform, tram-train booms and bus station.