Nenäinniemi sewage treatment plant

The Nenäinniemi sewage treatment plant in Jyväskylä plays a major role for the entire region. The treatment plant treats sewage from approximately 160,000 residents, almost 60 per cent of the population of Central Finland.

The renovation and extension of the Nenäinniemi sewage treatment plant was a significant project for the main contractor NYAB. In it, the company was able to benefit from decades of experience in building water utilities.

In the initial phase, the groundwater work was very demanding, and the construction phase as a whole was extensive. Around 100,000 cubic metres of land were excavated and used for landscaping nearby. Deep excavations require careful construction of supports. In turn, the winter season posed its own challenges, especially for large-scale concrete castings.

The expansion and renovation work took place while the sewage treatment plant was in use. Interesting research data on the positive environmental impacts of the investment has been obtained, as a thesis conducted at the Department of Biological and Environmental Sciences of the University of Jyväskylä showed that the Nenäinniemi sewage treatment plant is effectively recovering microplastics in sewage with a new disc filter.