The Radunia Canal (; ) is a historic canal completed in 1356 connecting the Radunia and Motà Âawa rivers, flowing through the cities of Pruszcz Gdaà Âski and Gdaà Âsk in Poland. It is listed on the regional heritage list.
The canal's course was dug out in 1338, and the canal itself was dug out between 1348 and 1356 by the State of the Teutonic Knights, which ruled Gdaà Âsk (then known as Danzig) at the time. It had two main purposes: powering the mills along its path and delivering drinking water to the city's inhabitants.
Up to the 1640s, the canal flowed directly into the Vistula, but was redirected to flow into the Motà Âawa instead. From 1539 to 1852, the Wasserkunst in Danzig, a pumping station which brought in drinking water from , was found on the canal's shores.
On 9 July 2001, during the 2001 flood in Gdaà Âsk, the canal overflowed, flooding the districts of Orunia-à Âw. Wojciech-Lipce and à Âródmieà Âcie.
The Canal begins in Pruszcz Gdaà Âski, near the village of Juszkowo, and continues straight north through Pruszcz. At the northern border of the city of Pruszcz, as it enters Gdaà Âsk proper, it loses its straight shape and continues with a winding course up to the quarter (osiedle) of . During that portion of the route, the Rotmanka Stream flows into it. It then returns to a straight course through Orunia and , with the flowing into it. In Zaroà Âlak, it is linked to the Opà Âyw Motà Âawy.
It then goes underground, flowing under railway lines and briefly being visible inside the shopping mall Forum Gdaà Âsk and eventually emerging in the Old Town, where it flows through two mills (the Maà Ây Mà Âyn and Wielki Mà Âyn, the latter of which was Europe's largest industrial plant during the Middle Ages), takes a turn, and flows into the Motà Âawa.
In 2011, a project began to modernize the Radunia Canal. Elements of the project included construction of shore protections, the strengthening and sealing of flood embankments, the reconstruction of several pedestrian bridges, and removal of sewage and water piping networks that moved through it. It was projected to cost 130 million zà Â. The project was completed in several phases, being partly completed in 2012 and fully in 2015.
In 2016 and 2017, two bridges across the Canal were built in Pruszcz Gdaà Âski. In 2018, a bridge in Orunia, carrying traffic on Starogardzka Street, was renovated. The most recently-built bridge was completed in 2020, also in Orunia-à Âw. Wojciech-Lipce, near the old Ferber Manor.