The present invention relates to a method for manufacturing a canal component which comprises a connection portion 104, 106 designed to come into contact with a component 100, in particular an adjacent canal component, which is to be connected to the canal component 100, the method comprising the following steps: providing a concrete base body, coating the base body with a plasticized plastics material 110 in the region of the connection portion 104, 106 and in the region of an internal wall (108) of the base body facing the canal inner space 106, and curing the plastics material (110).