Turning basin

A turning basin,[1] winding basin or swinging basin is a wider body of water, either located at the end of a ship canal or in a port to allow cargo ships to turn and reverse their direction of travel, or to enable long narrow barges in a canal to turn a sharp corner.

For a complete 180-degree turnaround, the width of the basin must be more than the length of the longest vessel normally traversing the waterway.

Onboard bow thrusters or tugboats may assist in manoeuvering the ship.

For seagoing vessels, PIANC guideline 121[3] recommends a diameter of 2 times the ship's length if tug assistance is present.

The Spanish guidelines for turning basins for seagoing vessels[4] provide very specific dimensions for different types of manoeuvres that may occur at a turning basin in a seaport.