As part of the Sopot Downtown Project, a vehicle tunnel was built along Grunwaldzka Street, enabling a collision-free connection of Sopot’s “Monciak” with the Pier.
The tunnel was located 3.6 m below sea level and approximately 5 m below the groundwater table. The implementation of the “Sopot Downtown” project also required the construction of new and alteration of existing infrastructure networks and modernization of the road system.

All works were carried out ensuring the continuity of operation of the network sections in operation, in particular rainwater and sanitary sewage systems. As part of the investment project, storm sewage networks with a total length of approximately 1,300 m, sanitary sewage networks with a length of 1,000 m, water supply networks with a length of 600 m and gas networks with a length of 300 m were built and modernized.

Accompanying investment projects were also completed, such as alteration of power and heating networks. The “Pośrednia” sewage pumping station was modernized, and the rainwater from the stream at ul. Bohaterów Monte Cassino was passed under the tunnel along Grunwaldzka-Powstańców Warszawy streets using a siphon, and the stream collector itself was rebuilt over a length of approximately 300 m.