A wave of investments is expected as wastewater treatment plants update their technologies to comply with the EU's revised wastewater treatment directive. Turku is involved in renewing and testing various technologies in a new pilot at the Turku region's wastewater treatment plant at Kakolanmäki.
The EU is renewing the wastewater treatment directive, as pollution caused by chemicals has become a major problem in water protection, alongside nutrients. The City of Turku is involved in the Kakolanmäki pilot, which is being implemented with the EMPEREST project funded by the European Union's Interreg Baltic Sea Region Programme.
The pilot containers incorporate several treatment technologies: granular and powdered activated carbon, UV disinfection, a pile cloth media filter and ozonation. Wastewater is passed through them to test how effectively different technologies remove micropollutants. The test equipment arriving in Turku was built in Tartu, Estonia, where it was also tested last year. The containers arrive in Turku from the Tallinn wastewater treatment plant. Another test equipment has also been built in Poland as part of the project and is being tested at treatment plants in Gdansk, Szczecin, Kaunas and Riga.
The new pilot containers of EMPEREST project arrived in Turku. Introduction for use was given by specialists from Estonia. In the picture (from the left): Mia Aitoukazzamane, Marlen Taggu, Ornella Mundi, Lotta Lehti, Joni Suojansalo, Nina Leino, Jarkko Laanti ja Jouko Tuomi.
PFAS compounds in focus
The project focuses particularly on removing PFAS compounds, or so-called forever chemicals, from wastewater. Per- and polyfluoroalkyl substances (PFAS) are a large, complex group of synthetic chemicals that are toxic and not do not degrade easily in the environment. PFAS substances enter the water from households, for example when they come off outdoor clothing when washing clothes or when small amounts of coating come off a Teflon pan when washing dishes. Many cosmetic products also contain PFAS compounds. Residues also enter wastewater from industrial processes. The easiest and most cost-effective way to remove forever chemicals would be to stop their production completely. Work is being done to achieve this, but while waiting for decisions, more efficient technology must be developed to remove them from water bodies.
– The pilot at the Turku wastewater treatment plant will be in operation for three months. Our aim for the pilot is to determine how to expand the existing installation to effectively remove new types of pollution specified in the aforementioned directive, says project coordinator Lotta Lehti.
Water samples will be taken at different stages of the process and analyzed in a laboratory. Laboratory results, procurement costs, operating experiences and other important information from all treatment plants participating in the experiment will be compiled in a report targeted at water operators and local authorities in the Baltic Sea region.
Improvements in water quality due to the Urban Wastewater Treatment Directive
The original Urban Wastewater Treatment Directive was enacted in 1991. The directive has brought about significant improvements in the state of water bodies, but its requirements no longer correspond to today's situation. The updated directive requires increasingly efficient nutrient removal and a completely new requirement is the removal of micropollutants, such as pharmaceuticals and harmful chemicals. The requirements are aimed in particular at wastewater treatment plants with a population equivalent of over 150,000.
The Turku region wastewater treatment plant is one of the eight large wastewater treatment plants in Finland that will be affected by the updated directive. In addition, the requirements are aimed at smaller wastewater treatment plants on a risk-based basis.
The City of Turku has more than a hundred externally funded projects, with an average annual value of EUR 60 million. External project funding is sourced from the European Union and Finnish funding programmes. The projects involve improving Turku in many ways and creating new operating models and innovations. With the external funding, Turku is also strongly involved in various national and international cooperation networks e.g. hosting the Union of the Baltic Cities Sustainable Cities Secretariat. The projects help to create a better Turku for everyone.