July the 28th, 2026 – Split is set to launch one of Croatia’s largest environmental projects as part of a massive 100 million euro investment.
Poslovni reports that construction works on this enormous project will last 28 months from the contractor being introduced to the site until the start of the plant’s trial operation. The total duration of the contract itself is 43 months, including the trial operation period and obtaining the operating permit.
One of the most important infrastructure projects in Croatia’s water management sector is now beginning in Split. On Tuesday, the 28th July 2026, the start of construction works on the Stupe Wastewater Treatment Plant (UPOV Stupe) will be officially marked. The project is a key part of the “Improvement of Water and Utility Infrastructure of the Split–Solin Agglomeration” initiative.
With the expansion of the Stupe wastewater treatment plant, Split will receive a modern wastewater treatment system that, once completed, will become the second-largest wastewater treatment facility in all of Croatia and the central point of a unified sewage system serving the Split–Solin agglomeration.
The value of the contract for the design and expansion of the facility amounts to 99,056,751.25 euros including VAT. The works will be carried out by a consortium consisting of WTE Wassertechnik GmbH (lead partner) and HERING d.d.
The future facility will have a capacity of 275,000 population equivalents, with secondary biological wastewater treatment. The construction of the Stupe wastewater treatment plant will provide modern treatment of municipal wastewater for Split and the surrounding area, helping to further protect the environment, preserve the quality of the Brač Channel, and improve the quality of life for residents.
As part of the second phase of the project, eligible costs amount to 243,149,745.48 euros. Of this, €165,365,077.30 euros will be financed through non-refundable European Union funds from the Cohesion Fund, while the remaining amount will be secured through Croatian national sources.
