Swedish construction company Peab has secured an additional SEK368m ($34.3m) contract from Stockholm Vatten och Avfall to rebuild the Henriksdal wastewater treatment plant in Stockholm, Sweden. This contract, part of the Stockholm Future Wastewater Treatment (SFA) project, is an option within an existing agreement and aims to enhance the plant’s capacity to serve 1.6 million people.

Peab will install an improved biological treatment process at the underground facility in Henriksdalsberget while ensuring continuous operation during construction. The work involves demolition, decontamination, and the construction of new basins. Initially, Peab was awarded a SEK254m contract in March 2021 to begin the plant’s redevelopment.

Henriksdal wastewater treatment plant, originally built in the 1930s, has undergone multiple upgrades to accommodate Stockholm’s growing population. Today, it consists of two interconnected facilities, Henriksdal and Sickla, linked by two 1km tunnels. The broader SFA project also includes constructing a new 14km sewage tunnel from Bromma to Sickla, developing a new Sickla treatment plant, and decommissioning the Bromma plant to free up land for urban development.

The upgrade aligns with Stockholm’s efforts to modernize its wastewater management infrastructure. In 2016, the Nordic Investment Bank (NIB) signed a ten-year SEK3bn loan agreement with the City of Stockholm to support the construction of an underground wastewater treatment facility.

Peab region manager Carl Johan Söderberg expressed confidence in the company’s ability to execute the project efficiently. He stated: “We’re pleased with the continued confidence in us from Stockholm Vatten och Avfall and that now we’ll begin to work on rebuilding Henriksdal’s Wastewater Treatment Plant. Through continued good cooperation, we’ll make sure that the treatment plant functions with minimal disruption during construction.”

Stockholm Vatten och Avfall, which operates the city’s wastewater treatment system, leads the SFA project. The initiative aims to improve water treatment efficiency and sustainability while expanding capacity.

Construction is set to begin in April 2025 and is expected to be completed by spring 2028.