The object of the project is the reconstruction of the existing polder “Iron” in Opole, which involves the reconstruction of existing water installations and the construction of new facilities in order to increase the capacity of polder and flood reserve. Polder Iron consists of two separate polders: Top Polder with area F = 165 ha and capacity V = 4.75 million m³, Polder bottom area F = 242 ha and capacity V = 4.95 million m³. The investment includes stages of: I. Reconstruction of the polder shaft “Polder Iron” (Part A) and modernisation of the “Iron” pumping station (Part B) together with objects functionally related for these devices, II. Reconstruction/construction of the polder shaft “Opole”, “Sławice-Iron” and “Iron”. Basic water equipment for “Iron” polder: Polder “Iron” polder shaft with overall length L = 5117 m together with functionally connected objects, polder shaft “Opole” of total length L = 2448 m together with objects functionally connected, polder shaft and polder shaft closing “Sławice-Iron” with the total length L = 4382 m including objects functionally connected, polder shaft closing “Żelazna” with 3254 functions of the total length L = 4382 m including objects functionally connected, polder shaft closing “Żelazna” with the total length of L = 4382 m, including objects functionally connected with “Zelznazna” with the total length of L = 4382 m, including the objects functionally connected with “Zelazna” with the total length L = 4382 m. The project included the reconstruction of 1 equipment for flood protection – the Iron Polder with accompanying infrastructure. The population benefiting from flood protection measures is 802 people. The volume of retained water is 9.70 million m³.