The project was divided into three sections. The first section is approximately 5.7 kilometres long and using Hobas jacking pipes OD 3,000, which are to be installed along the right side of the Vistula. So far a consortium of contractors Hydrobudowa 9, PRG Metro and KWG has completed 1,600 metres of the first section using two Herrenknecht microtunelling machines, AVN 2000 and 2400. Tunnelling on this section of the project progressed at an average of three metres per hour.

One of the challenges that was overcome in the first section was the high ground water level that lies around one to two metres below the surface, which translates to four to eight metres above the pipe top. In order to overcome this challenge, piles were set up around the thrust pits and jet-grouting was added to prevent too much water from pouring in.

An additional 1.4 kilometres of OD 3,000 will be laid on the left river bank. The final section includes the construction of a 4.5 metre diameter concrete tunnel, into which to lines DN 1,600 will be inserted, crossing beneath the Vistula. Pipes are currently being jacked beneath the main road of the district Białołęka.

The wastewater treatment plant Czajka is currently being constructed on the right river bank of the Vistula River in Warsaw, Poland. Following its completion, it will treat 80 per cent of the Polish capital’s effluents and ensure that no untreated sewage will harm the flora and fauna of the Vistula.