The subject of the project is preparatory work for two projects (concerning the updated WoD, which was submitted to the CUPT on 20.11.2020): 1. Construction of a flap weir on the water step of the Nysa estuary in km 180.50 of the Oder River with accompanying infrastructure, 2. Modernisation of the lock and control room at the water step of the Nysa estuary, together with the reconstruction of avantports and associated facilities, which resulted from the division of one major project called: “Construction of a flap weir on the water step Nysa estuary in km 180.50 rows. The Oder, including associated facilities.’ The above-mentioned preparatory work includes updating of construction projects, preparation of executive projects and tender documentation, obtaining administrative decisions, as well as regulating matters related to land purchase and land preparation (cutting) for reconstruction and improvement of the technical condition and conditions for the operation of weirs and locks at the water step of the Nysa estuary, which are elements of the Oderska Waterway in the Opolskie Voivodeship. The construction and modernisation of hydrotechnical facilities will be carried out in the next financial perspective for 2021-2027. The project was originally planned as an investment: The construction of a flap weir on the water step of the Nysa estuary in km 180.50 of the Oder River and accompanying infrastructure – WoD for such a range was approved on 23.06.2020. — the annex was signed on the basis of the updated WoD – approved on 02.12.2020.