29/08/2025
Soletanche Polska Builds the Foundations of a Retention Basin in Łacina Using Trenchmix®
In response to increasing climate-related challenges, the city of Poznań has launched an ambitious project in the Łacina district: the construction of an innovative retention basin that combines sustainable stormwater management, technical performance, and quality of life. Soletanche Polska has been commissioned to build the foundations of this structure using Trenchmix® soil mixing technology.
An essential tool against flooding
On behalf of AQUANET S.A., the general contractor PGTB Sp. z o.o. entrusted Soletanche Polska with the construction of the reservoir foundations. The primary purpose of this facility is to ensure the hydrological safety of a sensitive area of Poznań. Covering an area of approximately 2,800 m², it will be able to contain up to 1,900 m³ of rainwater or meltwater, temporarily stored before being discharged into the Warta River through the sewer system.
An innovative technology: Trenchmix®
The soil in Łacina presents major challenges: high groundwater levels, deep clay layers, and geotechnical instability. To address these issues, the teams implemented Trenchmix® technology, a deep soil mixing solution with binder. Soil mixing consumes fewer resources thanks to the reuse of in-situ soil, which reduces the need for water, cement, and aggregates. This technique generates little to no spoil, resulting in fewer materials to remove and lower CO² emissions from transportation.
Here, Soletanche Polska is building 263 linear meters of watertight walls up to 10 meters deep, ensuring the durability and impermeability of the structure.
A public space with added value
This reservoir is not just a technical facility: it is part of a broader sustainable development plan. Once completed, the area will be:
- landscaped and greened for leisure and relaxation,
- equipped with a rainwater harvesting system for irrigating green spaces,
- served by a new access road.
Well done to the teams!
