ECOPact saves 30% CO2 in major Croatia tunnel

Croatia’s landmark Istrian Y Motorway is using Holcim ECOPact concrete in the construction of a key tunnel, cutting its CO2 emissions by 30%. To drive circular construction, tunnel excavation material was used to produce the low-carbon concrete, saving over 200,000 tons of virgin aggregates.

Integrated solution for a landmark motorway in Croatia

120,000 m3 of ECOPact delivering 30% lower carbon emissions

Excavation material recycled into ECOPact saves 200,000 tons of virgin materials

The challenge 


Tourism is an important source of income for Croatia’s economy, so the development of major infrastructure such as roads and motorways is essential to ensure that both domestic and foreign tourists can easily access the country’s beautiful seaside. The Istrian Y Motorway is one such major infrastructure: It already sees 10 million vehicles per year, with over 60,000 vehicles per day during the peak summer period.

For investor Bina Istra and building firm Bouygues Construction, the project posed three main challenges: reducing its carbon footprint by choosing the right construction materials, adhering to the strictest environmental regulations because the construction site lies within the Učka Nature Park, and timely completion.

The current phase of the Istrian Y Motorway involves converting the remaining part of the current Y Expressway into a motorway and constructing the second pipe of the Učka Tunnel, which will connect the two major cities of Pula and Rijeka by a full-width motorway.

The solution


For this crucial project, Bina Istra and Bouygues Construction partnered with Holcim to find an integrated solution that would lower the project’s carbon footprint, close the material loop and improve the tunnel’s drainage during times of heavy rainfall.

To respond to the project’s strict performance, low-carbon and environmental demands, Holcim Croatia is supplying more than 120,000 m3 of ECOPact, the world’s broadest range of low-carbon concrete with CO2 reduction starting at 30% and no compromise in performance.

Additionally, Holcim is saving 200,000 tons of virgin materials by placing a mobile ready-mix plant onsite that uses tunnel excavation material for ECOPact concrete production. With the mobile plant, Holcim is not only driving circular construction but also reducing the environmental impact from transporting minerals from a quarry.

Bina Istra is a socially responsible company guided by the principles of sustainable development. Our goal is to reduce the carbon footprint of the Istrian Y Motorway and ECOPact is the perfect product to help us meet this need.

Dr. Dario Silic| Bina Istra General Manager

Finally, Hydromedia permeable concrete was also used to build the drainage channel. Hydromedia is a water management system that enables the ultra-rapid evacuation of water directly into the soil, reducing the risk of floods and puddles while producing a natural aquifer recharge.

The result


Thanks to the collaboration with Holcim and our ECOPact low-carbon concrete, the project will save approximately 9,000 tons of CO₂ by the time it’s completed, resulting in an emissions reduction of 30% when compared to a standard concrete mix in the market. This is the equivalent of 900 households’ average carbon emissions in the EU per year.

Upon completion, the Istrian Y motorway will better connect the Istria region with the rest of Europe.

With products like ECOPact, we show that we are part of the solution regarding climate change and at the forefront of driving circularity in the construction sector.

Mihaela Gortan Vozila| Head of Innovations and Projects at Holcim Croatia

A project’s carbon footprint is very important for Bouygues. That’s why we are constructing the tunnel in Croatia with concrete that offers an emissions reduction of at least 30%.

Luc Michel Dujmovic| Project Manager at Bouygues Construction

Our ECOPact projects

slide left
slide right